diff --git a/Makefile b/Makefile
index 04bbb48d..9a8e220b 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,7 @@ UF_LIBS 				=
 # EXT_LIBS 	 			= -lpng16 -lz -lassimp -lsfml-main -lsfml-system -lsfml-window -lsfml-graphics -llua52
 # EXT_LIBS 	 			= -lpng16 -lz -lassimp -ljsoncpp -lopenal32 -lalut -lvorbis -lvorbisfile -logg -lfreetype
 EXT_LIBS 				=
-#FLAGS 					= -std=c++0x -Wall -g -DUF_USE_JSON -DUF_USE_NCURSES -DUF_USE_OPENGL -DUF_USE_GLEW
+#FLAGS 					= -Og -DUF_DISABLE_ALIGNAS -std=c++20 -Wno-c++11-narrowing -Wno-narrowing -g -DVK_USE_PLATFORM_WIN32_KHR -DUF_USE_VULKAN -DGLM_ENABLE_EXPERIMENTAL -DUF_USE_JSON -DUF_USE_NCURSES -DUF_USE_OPENAL -DUF_USE_VORBIS -DUF_USE_FREETYPE -DUSE_OPENVR_MINGW
 FLAGS 					= -std=c++20 -Wno-c++11-narrowing -Wno-narrowing -g -DVK_USE_PLATFORM_WIN32_KHR -DUF_USE_VULKAN -DGLM_ENABLE_EXPERIMENTAL -DUF_USE_JSON -DUF_USE_NCURSES -DUF_USE_OPENAL -DUF_USE_VORBIS -DUF_USE_FREETYPE -DUSE_OPENVR_MINGW
 #-march=native
 LIB_NAME 				= uf
diff --git a/bin/data/shaders/base.frag.glsl b/bin/data/shaders/base.frag.glsl
index c87cec11..3277d475 100644
--- a/bin/data/shaders/base.frag.glsl
+++ b/bin/data/shaders/base.frag.glsl
@@ -3,19 +3,20 @@
 layout (binding = 1) uniform sampler2D samplerColor;
 
 layout (location = 0) in vec2 inUv;
-layout (location = 1) in vec3 inPosition;
+layout (location = 1) in vec4 inColor;
 layout (location = 2) in vec3 inNormal;
-layout (location = 3) in vec4 inColor;
+layout (location = 3) in vec3 inPosition;
 
 layout (location = 0) out vec4 outAlbedoSpecular;
-layout (location = 1) out vec4 outPosition;
-layout (location = 2) out vec4 outNormal;
+layout (location = 1) out vec4 outNormal;
+layout (location = 2) out vec4 outPosition;
 
 void main() {
 	outAlbedoSpecular = texture(samplerColor, inUv);
 	if ( outAlbedoSpecular.a < 0.001 ) discard;
 	outAlbedoSpecular.rgb *= inColor.rgb;
 	outAlbedoSpecular.a = 1;
-//	outPosition = vec4(inPosition, 1.0);
-//	outNormal = vec4(normalize(inNormal), 1.0);
+	
+	outNormal = vec4(inNormal,1);
+	outPosition = vec4(inPosition,1);
 }
\ No newline at end of file
diff --git a/bin/data/shaders/base.stereo.vert.glsl b/bin/data/shaders/base.stereo.vert.glsl
index 0b0af656..18a8318b 100644
--- a/bin/data/shaders/base.stereo.vert.glsl
+++ b/bin/data/shaders/base.stereo.vert.glsl
@@ -20,9 +20,9 @@ layout (binding = 0) uniform UBO {
 } ubo;
 
 layout (location = 0) out vec2 outUv;
-layout (location = 1) out vec3 outPosition;
+layout (location = 1) out vec4 outColor;
 layout (location = 2) out vec3 outNormal;
-layout (location = 3) out vec4 outColor;
+layout (location = 3) out vec3 outPosition;
 
 out gl_PerVertex {
     vec4 gl_Position;   
@@ -35,9 +35,7 @@ void main() {
 
 	outPosition = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
 	outNormal = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inNormal.xyz, 0.0));
-
-//	outPosition = vec3(ubo.matrices.model * vec4(inPos.xyz, 1.0));
-//	outNormal = vec3(ubo.matrices.model * vec4(inNormal.xyz, 0.0));
+	outNormal = normalize(outNormal);
 
 	gl_Position = ubo.matrices.projection[PushConstant.pass] * ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0);
 }
\ No newline at end of file
diff --git a/bin/data/shaders/base.vert.glsl b/bin/data/shaders/base.vert.glsl
deleted file mode 100644
index 1bb77302..00000000
--- a/bin/data/shaders/base.vert.glsl
+++ /dev/null
@@ -1,39 +0,0 @@
-#version 450
-
-layout (location = 0) in vec3 inPos;
-layout (location = 1) in vec2 inUv;
-layout (location = 2) in vec3 inNormal;
-
-layout( push_constant ) uniform PushBlock {
-  uint pass;
-} PushConstant;
-
-struct Matrices {
-	mat4 model;
-	mat4 view[2];
-	mat4 projection[2];
-};
-
-layout (binding = 0) uniform UBO {
-	Matrices matrices;
-	vec4 color;
-} ubo;
-
-layout (location = 0) out vec2 outUv;
-layout (location = 1) out vec3 outPositionEye;
-layout (location = 2) out vec3 outNormalEye;
-layout (location = 3) out vec4 outColor;
-
-out gl_PerVertex {
-    vec4 gl_Position;   
-};
-
-
-void main() {
-	outUv = inUv;
-	outPositionEye = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
-	outNormalEye = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inNormal.xyz, 0.0));
-	outColor = ubo.color;
-
-	gl_Position = ubo.matrices.projection[PushConstant.pass] * ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0);
-}
\ No newline at end of file
diff --git a/bin/data/shaders/display.frag.glsl b/bin/data/shaders/display.frag.glsl
deleted file mode 100644
index 1ca52c32..00000000
--- a/bin/data/shaders/display.frag.glsl
+++ /dev/null
@@ -1,10 +0,0 @@
-#version 450
-
-layout (input_attachment_index = 0, binding = 1) uniform subpassInput samplerOutput;
-
-layout (location = 0) in vec2 inUv;
-layout (location = 0) out vec4 outFragColor;
-
-void main() {
-	outFragColor = subpassLoad(samplerOutput);
-}
\ No newline at end of file
diff --git a/bin/data/shaders/display.rendertarget.frag.glsl b/bin/data/shaders/display.rendertarget.frag.glsl
index 00d969ef..641f6d2d 100644
--- a/bin/data/shaders/display.rendertarget.frag.glsl
+++ b/bin/data/shaders/display.rendertarget.frag.glsl
@@ -3,8 +3,7 @@
 
 layout (binding = 1) uniform sampler samp;
 layout (binding = 2) uniform texture2D albedoTexture;
-layout (binding = 3) uniform texture2D positionTexture;
-layout (binding = 4) uniform texture2D normalTexture;
+layout (binding = 3) uniform texture2D normalTexture;
 
 struct Cursor {
 	vec2 position;
@@ -17,8 +16,7 @@ layout (location = 1) in float inAlpha;
 layout (location = 2) in Cursor inCursor;
 
 layout (location = 0) out vec4 outAlbedoSpecular;
-layout (location = 1) out vec4 outPosition;
-layout (location = 2) out vec4 outNormal;
+layout (location = 1) out vec4 outNormal;
 
 void main() {
 	outAlbedoSpecular = texture(sampler2D(albedoTexture, samp), inUv);
@@ -26,7 +24,6 @@ void main() {
 		vec2 uv = gl_FragCoord.xy / textureSize(albedoTexture, 0);
 		// uv.x = 1-uv.x;
 		outAlbedoSpecular = texture(sampler2D(albedoTexture, samp), uv);
-		outPosition = texture(sampler2D(positionTexture, samp), uv);
 		outNormal = texture(sampler2D(normalTexture, samp), uv);
 		if ( outAlbedoSpecular.a < 0.01f ) outAlbedoSpecular = vec4(0,0,0,1);
 		return;
diff --git a/bin/data/shaders/display.rendertarget.vert.glsl b/bin/data/shaders/display.rendertarget.vert.glsl
index 7ee36239..651c07f7 100644
--- a/bin/data/shaders/display.rendertarget.vert.glsl
+++ b/bin/data/shaders/display.rendertarget.vert.glsl
@@ -27,7 +27,7 @@ struct Matrices {
 layout (binding = 0) uniform UBO {
 	Matrices matrices;
 	Cursor cursor;
-	float alpha;
+	vec2 alpha;
 } ubo;
 
 void main() {
diff --git a/bin/data/shaders/display.subpass.frag.glsl b/bin/data/shaders/display.subpass.frag.glsl
index 39df87b0..609843a7 100644
--- a/bin/data/shaders/display.subpass.frag.glsl
+++ b/bin/data/shaders/display.subpass.frag.glsl
@@ -1,22 +1,29 @@
 #version 450
 
+#define BASE_LIGHTS_SIZE 16
+layout (constant_id = 0) const uint LIGHTS = BASE_LIGHTS_SIZE;
+
 layout (input_attachment_index = 0, binding = 1) uniform subpassInput samplerAlbedo;
-layout (input_attachment_index = 0, binding = 2) uniform subpassInput samplerPosition;
-layout (input_attachment_index = 0, binding = 3) uniform subpassInput samplerNormal;
-layout (input_attachment_index = 0, binding = 4) uniform subpassInput samplerDepth;
+layout (input_attachment_index = 0, binding = 2) uniform subpassInput samplerNormal;
+layout (input_attachment_index = 0, binding = 3) uniform subpassInput samplerPosition;
+// layout (input_attachment_index = 0, binding = 4) uniform subpassInput samplerDepth;
+layout (binding = 5) uniform sampler2D samplerShadows[BASE_LIGHTS_SIZE];
 
 layout (location = 0) in vec2 inUv;
 layout (location = 1) in flat uint inPushConstantPass;
 
 layout (location = 0) out vec4 outFragColor;
 
-layout (constant_id = 0) const uint LIGHTS = 32;
 
 struct Light {
 	vec3 position;
 	float power;
 	vec3 color;
 	float radius;
+	int type;
+	int shadowed;
+	mat4 view;
+	mat4 projection;
 };
 
 struct Matrices {
@@ -78,31 +85,117 @@ void phong( Light light, vec4 albedoSpecular, inout vec3 i ) {
 	i += Id * light.power;
 }
 
+bool debugShadow( Light light, uint i ) {
+	return false;
+
+	vec4 positionClip = light.projection * light.view * vec4(position.world, 1.0);
+	positionClip.xyz /= positionClip.w;
+	float lightDepth = texture(samplerShadows[i], positionClip.xy * 0.5 + 0.5).r;
+
+	float eyeDepth = positionClip.z;
+	eyeDepth = lightDepth;
+	float bias = 0.0005;
+
+		 if ( positionClip.x < -1 || positionClip.x >= 1 ) eyeDepth = 1;
+	else if ( positionClip.y < -1 || positionClip.y >= 1 ) eyeDepth = 1;
+	else if ( positionClip.z <  0 || positionClip.z >= 1 ) eyeDepth = 1;
+	// else eyeDepth /= 0.00526;
+
+	outFragColor.rgb = vec3( 1 - eyeDepth );
+	outFragColor.a = 1;
+	
+	return true;
+}
+
+float shadowFactor( Light light, uint i ) {
+	vec4 positionClip = light.projection * light.view * vec4(position.world, 1.0);
+	positionClip.xyz /= positionClip.w;
+	float lightDepth = texture(samplerShadows[i], positionClip.xy * 0.5 + 0.5).r;
+	float eyeDepth = positionClip.z;
+	float bias = 0.0005;
+	// bias = max(0.05 * (1.0 - dot(normal.eye, light.position.xyz - position.eye)), bias);
+
+//	eyeDepth /= 0.00526;
+//	lightDepth /= 0.00526;
+
+	eyeDepth = 1 - eyeDepth;
+	lightDepth = 1 - lightDepth;
+
+	if ( positionClip.x < -1 || positionClip.x >= 1 ) return 0.0;
+	if ( positionClip.y < -1 || positionClip.y >= 1 ) return 0.0;
+	if ( positionClip.z <  0 || positionClip.z >= 1 ) return 0.0;
+
+	return eyeDepth - bias < lightDepth ? 1.0 : 0.0;
+}
+
 void main() {
 	vec4 albedoSpecular = subpassLoad(samplerAlbedo);
-	position.eye = subpassLoad(samplerPosition).rgb;
 	normal.eye = subpassLoad(samplerNormal).rgb;
+	position.eye = subpassLoad(samplerPosition).rgb;
 
 	{
-		float depth = subpassLoad(samplerDepth).r;
+		mat4 iView = inverse( ubo.matrices.view[inPushConstantPass] );
+		vec4 positionWorld = iView * vec4(position.eye, 1);
+		position.world = positionWorld.xyz;
+	}
+/*
+	{
 		mat4 iProj = inverse( ubo.matrices.projection[inPushConstantPass] );
+		mat4 iView = inverse( ubo.matrices.view[inPushConstantPass] );
+
+		float depth = subpassLoad(samplerDepth).r;
+
+		if ( false ) {
+			depth /= 0.00526;
+			outFragColor.rgb = vec3( 1 - depth );
+			outFragColor.a = 1;
+			return;
+		}
+		
 		vec4 positionClip = vec4(inUv * 2.0 - 1.0, depth, 1.0);
-		positionClip.y *= -1;
 		vec4 positionEye = iProj * positionClip;
 		positionEye /= positionEye.w;
 		position.eye = positionEye.xyz;
+
+		vec4 positionWorld = iView * positionEye;
+		position.world = positionWorld.xyz;
 	}
+*/
 
 	vec3 fragColor = albedoSpecular.rgb * ubo.ambient.rgb;
 	bool lit = false;
 	for ( uint i = 0; i < LIGHTS; ++i ) {
 		Light light = ubo.lights[i];
+		
 		if ( light.power <= 0.001 ) continue;
 		lit = true;
+		
 		light.position.xyz = vec3(ubo.matrices.view[inPushConstantPass] * vec4(light.position.xyz, 1));
+
+		if ( light.shadowed > 0 ) {
+			float shadowFactor = shadowFactor( light, i );
+			if ( shadowFactor <= 0.0001 ) continue;
+		}
 		phong( light, albedoSpecular, fragColor );
 	}
+	
 	if ( !lit ) fragColor = albedoSpecular.rgb;
+	
 	fog(fragColor);
+
 	outFragColor = vec4(fragColor,1);
+/*
+	if ( !false ) {
+		float depth = texture(samplerShadows[0], inUv).r;
+		depth /= 0.00526;
+		outFragColor = vec4( vec3(1 - depth), 1 );
+		return;
+	} else if ( !false ) {
+		outFragColor = vec4( texture(samplerShadows[0], inUv).rgb, 1 );
+		return;
+	} else {
+		outFragColor = vec4( inUv.x, 0, inUv.y, 1 );
+		return;
+	}
+*/
 }
\ No newline at end of file
diff --git a/bin/data/shaders/heightmap.frag.glsl b/bin/data/shaders/heightmap.frag.glsl
index 77e8fd76..7aa5d840 100644
--- a/bin/data/shaders/heightmap.frag.glsl
+++ b/bin/data/shaders/heightmap.frag.glsl
@@ -3,19 +3,17 @@
 layout (binding = 1) uniform sampler2D samplerColor;
 
 layout (location = 0) in vec2 inUv;
-layout (location = 1) in vec3 inPosition;
-layout (location = 2) in vec3 inNormal;
-layout (location = 3) in vec4 inColor;
+layout (location = 1) in vec3 inNormal;
+layout (location = 2) in vec4 inColor;
 
 layout (location = 0) out vec4 outAlbedoSpecular;
-layout (location = 1) out vec4 outPosition;
-layout (location = 2) out vec4 outNormal;
+layout (location = 1) out vec4 outNormal;
 
 void main() {
 	outAlbedoSpecular = texture(samplerColor, inUv);
 	outAlbedoSpecular = vec4(1,1,1,1);
 	outAlbedoSpecular.rgb *= inColor.rgb;
 	outAlbedoSpecular.a = 1;
-	outPosition = vec4(inPosition, 1.0);
+//	outPosition = vec4(inPosition, 1.0);
 	outNormal = vec4(normalize(inNormal), 1.0);
 }
\ No newline at end of file
diff --git a/bin/data/shaders/heightmap.stereo.vert.glsl b/bin/data/shaders/heightmap.stereo.vert.glsl
index bca53477..692ac3b2 100644
--- a/bin/data/shaders/heightmap.stereo.vert.glsl
+++ b/bin/data/shaders/heightmap.stereo.vert.glsl
@@ -21,9 +21,8 @@ layout (binding = 0) uniform UBO {
 } ubo;
 
 layout (location = 0) out vec2 outUv;
-layout (location = 1) out vec3 outPosition;
-layout (location = 2) out vec3 outNormal;
-layout (location = 3) out vec4 outColor;
+layout (location = 1) out vec3 outNormal;
+layout (location = 2) out vec4 outColor;
 
 out gl_PerVertex {
     vec4 gl_Position;   
@@ -34,7 +33,7 @@ void main() {
 	outUv = inUv;
 //	outColor = ubo.color;
 
-	outPosition = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
+//	outPosition = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
 	outNormal = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inNormal.xyz, 0.0));
 
 //	outPosition = vec3(ubo.matrices.model * vec4(inPos.xyz, 1.0));
diff --git a/bin/data/shaders/line.frag.glsl b/bin/data/shaders/line.frag.glsl
index 20964f0d..b996dd27 100644
--- a/bin/data/shaders/line.frag.glsl
+++ b/bin/data/shaders/line.frag.glsl
@@ -1,7 +1,6 @@
 #version 450
 
-layout (location = 0) in vec3 inPosition;
-layout (location = 1) in vec3 inColor;
+layout (location = 0) in vec3 inColor;
 
 layout (location = 0) out vec4 outAlbedoSpecular;
 
diff --git a/bin/data/shaders/line.stereo.vert.glsl b/bin/data/shaders/line.stereo.vert.glsl
index 863f2b34..45f26062 100644
--- a/bin/data/shaders/line.stereo.vert.glsl
+++ b/bin/data/shaders/line.stereo.vert.glsl
@@ -17,8 +17,7 @@ layout (binding = 0) uniform UBO {
 	vec4 color;
 } ubo;
 
-layout (location = 0) out vec3 outPosition;
-layout (location = 1) out vec4 outColor;
+layout (location = 0) out vec4 outColor;
 
 out gl_PerVertex {
     vec4 gl_Position;   
@@ -28,7 +27,7 @@ out gl_PerVertex {
 void main() {
 	outColor = ubo.color;
 
-	outPosition = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
+//	outPosition = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
 
 	gl_Position = ubo.matrices.projection[PushConstant.pass] * ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0);
 }
\ No newline at end of file
diff --git a/bin/data/shaders/terrain.frag.glsl b/bin/data/shaders/terrain.frag.glsl
index db1e9385..cfe7cd4b 100644
--- a/bin/data/shaders/terrain.frag.glsl
+++ b/bin/data/shaders/terrain.frag.glsl
@@ -3,18 +3,18 @@
 layout (binding = 1) uniform sampler2D samplerColor;
 
 layout (location = 0) in vec2 inUv;
-layout (location = 1) in vec3 inPosition;
+layout (location = 1) in vec4 inColor;
 layout (location = 2) in vec3 inNormal;
-layout (location = 3) in vec4 inColor;
+layout (location = 3) in vec3 inPosition;
 
 layout (location = 0) out vec4 outAlbedoSpecular;
-layout (location = 1) out vec4 outPosition;
-layout (location = 2) out vec4 outNormal;
+layout (location = 1) out vec4 outNormal;
+layout (location = 2) out vec4 outPosition;
 
 void main() {
 	outAlbedoSpecular = texture(samplerColor, inUv);
-	outAlbedoSpecular.rgb *= inColor.rgb;
+	// outAlbedoSpecular.rgb *= inColor.rgb;
 	outAlbedoSpecular.a = 1;
-	outPosition = vec4(inPosition, 1.0);
-	outNormal = vec4(normalize(inNormal), 1.0);
+	outNormal = vec4(inNormal,1);
+	outPosition = vec4(inPosition,1);
 }
\ No newline at end of file
diff --git a/bin/data/shaders/terrain.stereo.vert.glsl b/bin/data/shaders/terrain.stereo.vert.glsl
index bca53477..2740f83b 100644
--- a/bin/data/shaders/terrain.stereo.vert.glsl
+++ b/bin/data/shaders/terrain.stereo.vert.glsl
@@ -21,9 +21,9 @@ layout (binding = 0) uniform UBO {
 } ubo;
 
 layout (location = 0) out vec2 outUv;
-layout (location = 1) out vec3 outPosition;
+layout (location = 1) out vec4 outColor;
 layout (location = 2) out vec3 outNormal;
-layout (location = 3) out vec4 outColor;
+layout (location = 3) out vec3 outPosition;
 
 out gl_PerVertex {
     vec4 gl_Position;   
@@ -36,9 +36,7 @@ void main() {
 
 	outPosition = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
 	outNormal = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inNormal.xyz, 0.0));
-
-//	outPosition = vec3(ubo.matrices.model * vec4(inPos.xyz, 1.0));
-//	outNormal = vec3(ubo.matrices.model * vec4(inNormal.xyz, 0.0));
+	outNormal = normalize(outNormal);
 
 	outColor.a = (inColor >>  24u) & 0xFF;
 	outColor.b = (inColor >>  16u) & 0xFF;
diff --git a/bin/data/shaders/terrain.vert.glsl b/bin/data/shaders/terrain.vert.glsl
deleted file mode 100644
index 8b88188a..00000000
--- a/bin/data/shaders/terrain.vert.glsl
+++ /dev/null
@@ -1,47 +0,0 @@
-#version 450
-
-layout (location = 0) in vec3 inPos;
-layout (location = 1) in vec2 inUv;
-layout (location = 2) in vec3 inNormal;
-layout (location = 3) in uint inColor;
-
-layout( push_constant ) uniform PushBlock {
-  uint pass;
-} PushConstant;
-
-struct Matrices {
-	mat4 model;
-	mat4 view[2];
-	mat4 projection[2];
-};
-
-layout (binding = 0) uniform UBO {
-	Matrices matrices;
-	vec4 color;
-} ubo;
-
-layout (location = 0) out vec2 outUv;
-layout (location = 1) out vec3 outPositionEye;
-layout (location = 2) out vec3 outNormalEye;
-layout (location = 3) out vec4 outColor;
-
-out gl_PerVertex {
-    vec4 gl_Position;   
-};
-
-
-void main() {
-	outUv = inUv;
-	outPositionEye = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0));
-	outNormalEye = vec3(ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inNormal.xyz, 0.0));
-//	outColor = ubo.color;
-
-	outColor.a = (inColor >>  24u) & 0xFF;
-	outColor.b = (inColor >>  16u) & 0xFF;
-	outColor.g = (inColor >>   8u) & 0xFF;
-	outColor.r = (inColor        ) & 0xFF;
-	outColor.rgb /= 256.0;
-	outColor.a = 0.5;
-
-	gl_Position = ubo.matrices.projection[PushConstant.pass] * ubo.matrices.view[PushConstant.pass] * ubo.matrices.model * vec4(inPos.xyz, 1.0);
-}
\ No newline at end of file
diff --git a/engine/inc/gltf/json.hpp b/engine/inc/gltf/json.hpp
new file mode 100644
index 00000000..c9af0bed
--- /dev/null
+++ b/engine/inc/gltf/json.hpp
@@ -0,0 +1,20406 @@
+/*
+    __ _____ _____ _____
+ __|  |   __|     |   | |  JSON for Modern C++
+|  |  |__   |  |  | | | |  version 3.5.0
+|_____|_____|_____|_|___|  https://github.com/nlohmann/json
+
+Licensed under the MIT License <http://opensource.org/licenses/MIT>.
+SPDX-License-Identifier: MIT
+Copyright (c) 2013-2018 Niels Lohmann <http://nlohmann.me>.
+
+Permission is hereby  granted, free of charge, to any  person obtaining a copy
+of this software and associated  documentation files (the "Software"), to deal
+in the Software  without restriction, including without  limitation the rights
+to  use, copy,  modify, merge,  publish, distribute,  sublicense, and/or  sell
+copies  of  the Software,  and  to  permit persons  to  whom  the Software  is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE  IS PROVIDED "AS  IS", WITHOUT WARRANTY  OF ANY KIND,  EXPRESS OR
+IMPLIED,  INCLUDING BUT  NOT  LIMITED TO  THE  WARRANTIES OF  MERCHANTABILITY,
+FITNESS FOR  A PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO EVENT  SHALL THE
+AUTHORS  OR COPYRIGHT  HOLDERS  BE  LIABLE FOR  ANY  CLAIM,  DAMAGES OR  OTHER
+LIABILITY, WHETHER IN AN ACTION OF  CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE  OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#ifndef NLOHMANN_JSON_HPP
+#define NLOHMANN_JSON_HPP
+
+#define NLOHMANN_JSON_VERSION_MAJOR 3
+#define NLOHMANN_JSON_VERSION_MINOR 5
+#define NLOHMANN_JSON_VERSION_PATCH 0
+
+#include <algorithm> // all_of, find, for_each
+#include <cassert> // assert
+#include <ciso646> // and, not, or
+#include <cstddef> // nullptr_t, ptrdiff_t, size_t
+#include <functional> // hash, less
+#include <initializer_list> // initializer_list
+#include <iosfwd> // istream, ostream
+#include <iterator> // random_access_iterator_tag
+#include <numeric> // accumulate
+#include <string> // string, stoi, to_string
+#include <utility> // declval, forward, move, pair, swap
+
+// #include <nlohmann/json_fwd.hpp>
+#ifndef NLOHMANN_JSON_FWD_HPP
+#define NLOHMANN_JSON_FWD_HPP
+
+#include <cstdint> // int64_t, uint64_t
+#include <map> // map
+#include <memory> // allocator
+#include <string> // string
+#include <vector> // vector
+
+/*!
+@brief namespace for Niels Lohmann
+@see https://github.com/nlohmann
+@since version 1.0.0
+*/
+namespace nlohmann
+{
+/*!
+@brief default JSONSerializer template argument
+
+This serializer ignores the template arguments and uses ADL
+([argument-dependent lookup](https://en.cppreference.com/w/cpp/language/adl))
+for serialization.
+*/
+template<typename T = void, typename SFINAE = void>
+struct adl_serializer;
+
+template<template<typename U, typename V, typename... Args> class ObjectType =
+         std::map,
+         template<typename U, typename... Args> class ArrayType = std::vector,
+         class StringType = std::string, class BooleanType = bool,
+         class NumberIntegerType = std::int64_t,
+         class NumberUnsignedType = std::uint64_t,
+         class NumberFloatType = double,
+         template<typename U> class AllocatorType = std::allocator,
+         template<typename T, typename SFINAE = void> class JSONSerializer =
+         adl_serializer>
+class basic_json;
+
+/*!
+@brief JSON Pointer
+
+A JSON pointer defines a string syntax for identifying a specific value
+within a JSON document. It can be used with functions `at` and
+`operator[]`. Furthermore, JSON pointers are the base for JSON patches.
+
+@sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
+
+@since version 2.0.0
+*/
+template<typename BasicJsonType>
+class json_pointer;
+
+/*!
+@brief default JSON class
+
+This type is the default specialization of the @ref basic_json class which
+uses the standard template types.
+
+@since version 1.0.0
+*/
+using json = basic_json<>;
+}  // namespace nlohmann
+
+#endif
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+
+// This file contains all internal macro definitions
+// You MUST include macro_unscope.hpp at the end of json.hpp to undef all of them
+
+// exclude unsupported compilers
+#if !defined(JSON_SKIP_UNSUPPORTED_COMPILER_CHECK)
+    #if defined(__clang__)
+        #if (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__) < 30400
+            #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
+        #endif
+    #elif defined(__GNUC__) && !(defined(__ICC) || defined(__INTEL_COMPILER))
+        #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40800
+            #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
+        #endif
+    #endif
+#endif
+
+// disable float-equal warnings on GCC/clang
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+    #pragma GCC diagnostic push
+    #pragma GCC diagnostic ignored "-Wfloat-equal"
+#endif
+
+// disable documentation warnings on clang
+#if defined(__clang__)
+    #pragma GCC diagnostic push
+    #pragma GCC diagnostic ignored "-Wdocumentation"
+#endif
+
+// allow for portable deprecation warnings
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+    #define JSON_DEPRECATED __attribute__((deprecated))
+#elif defined(_MSC_VER)
+    #define JSON_DEPRECATED __declspec(deprecated)
+#else
+    #define JSON_DEPRECATED
+#endif
+
+// allow to disable exceptions
+#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)) && !defined(JSON_NOEXCEPTION)
+    #define JSON_THROW(exception) throw exception
+    #define JSON_TRY try
+    #define JSON_CATCH(exception) catch(exception)
+    #define JSON_INTERNAL_CATCH(exception) catch(exception)
+#else
+    #define JSON_THROW(exception) std::abort()
+    #define JSON_TRY if(true)
+    #define JSON_CATCH(exception) if(false)
+    #define JSON_INTERNAL_CATCH(exception) if(false)
+#endif
+
+// override exception macros
+#if defined(JSON_THROW_USER)
+    #undef JSON_THROW
+    #define JSON_THROW JSON_THROW_USER
+#endif
+#if defined(JSON_TRY_USER)
+    #undef JSON_TRY
+    #define JSON_TRY JSON_TRY_USER
+#endif
+#if defined(JSON_CATCH_USER)
+    #undef JSON_CATCH
+    #define JSON_CATCH JSON_CATCH_USER
+    #undef JSON_INTERNAL_CATCH
+    #define JSON_INTERNAL_CATCH JSON_CATCH_USER
+#endif
+#if defined(JSON_INTERNAL_CATCH_USER)
+    #undef JSON_INTERNAL_CATCH
+    #define JSON_INTERNAL_CATCH JSON_INTERNAL_CATCH_USER
+#endif
+
+// manual branch prediction
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+    #define JSON_LIKELY(x)      __builtin_expect(!!(x), 1)
+    #define JSON_UNLIKELY(x)    __builtin_expect(!!(x), 0)
+#else
+    #define JSON_LIKELY(x)      x
+    #define JSON_UNLIKELY(x)    x
+#endif
+
+// C++ language standard detection
+#if (defined(__cplusplus) && __cplusplus >= 201703L) || (defined(_HAS_CXX17) && _HAS_CXX17 == 1) // fix for issue #464
+    #define JSON_HAS_CPP_17
+    #define JSON_HAS_CPP_14
+#elif (defined(__cplusplus) && __cplusplus >= 201402L) || (defined(_HAS_CXX14) && _HAS_CXX14 == 1)
+    #define JSON_HAS_CPP_14
+#endif
+
+/*!
+@brief macro to briefly define a mapping between an enum and JSON
+@def NLOHMANN_JSON_SERIALIZE_ENUM
+@since version 3.4.0
+*/
+#define NLOHMANN_JSON_SERIALIZE_ENUM(ENUM_TYPE, ...)                                           \
+    template<typename BasicJsonType>                                                           \
+    inline void to_json(BasicJsonType& j, const ENUM_TYPE& e)                                  \
+    {                                                                                          \
+        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");         \
+        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                    \
+        auto it = std::find_if(std::begin(m), std::end(m),                                     \
+                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
+        {                                                                                      \
+            return ej_pair.first == e;                                                         \
+        });                                                                                    \
+        j = ((it != std::end(m)) ? it : std::begin(m))->second;                                \
+    }                                                                                          \
+    template<typename BasicJsonType>                                                           \
+    inline void from_json(const BasicJsonType& j, ENUM_TYPE& e)                                \
+    {                                                                                          \
+        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");         \
+        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                    \
+        auto it = std::find_if(std::begin(m), std::end(m),                                     \
+                               [j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
+        {                                                                                      \
+            return ej_pair.second == j;                                                        \
+        });                                                                                    \
+        e = ((it != std::end(m)) ? it : std::begin(m))->first;                                 \
+    }
+
+// Ugly macros to avoid uglier copy-paste when specializing basic_json. They
+// may be removed in the future once the class is split.
+
+#define NLOHMANN_BASIC_JSON_TPL_DECLARATION                                \
+    template<template<typename, typename, typename...> class ObjectType,   \
+             template<typename, typename...> class ArrayType,              \
+             class StringType, class BooleanType, class NumberIntegerType, \
+             class NumberUnsignedType, class NumberFloatType,              \
+             template<typename> class AllocatorType,                       \
+             template<typename, typename = void> class JSONSerializer>
+
+#define NLOHMANN_BASIC_JSON_TPL                                            \
+    basic_json<ObjectType, ArrayType, StringType, BooleanType,             \
+    NumberIntegerType, NumberUnsignedType, NumberFloatType,                \
+    AllocatorType, JSONSerializer>
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+
+#include <ciso646> // not
+#include <cstddef> // size_t
+#include <type_traits> // conditional, enable_if, false_type, integral_constant, is_constructible, is_integral, is_same, remove_cv, remove_reference, true_type
+
+namespace nlohmann
+{
+namespace detail
+{
+// alias templates to reduce boilerplate
+template<bool B, typename T = void>
+using enable_if_t = typename std::enable_if<B, T>::type;
+
+template<typename T>
+using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
+
+// implementation of C++14 index_sequence and affiliates
+// source: https://stackoverflow.com/a/32223343
+template<std::size_t... Ints>
+struct index_sequence
+{
+    using type = index_sequence;
+    using value_type = std::size_t;
+    static constexpr std::size_t size() noexcept
+    {
+        return sizeof...(Ints);
+    }
+};
+
+template<class Sequence1, class Sequence2>
+struct merge_and_renumber;
+
+template<std::size_t... I1, std::size_t... I2>
+struct merge_and_renumber<index_sequence<I1...>, index_sequence<I2...>>
+        : index_sequence < I1..., (sizeof...(I1) + I2)... > {};
+
+template<std::size_t N>
+struct make_index_sequence
+    : merge_and_renumber < typename make_index_sequence < N / 2 >::type,
+      typename make_index_sequence < N - N / 2 >::type > {};
+
+template<> struct make_index_sequence<0> : index_sequence<> {};
+template<> struct make_index_sequence<1> : index_sequence<0> {};
+
+template<typename... Ts>
+using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
+
+// dispatch utility (taken from ranges-v3)
+template<unsigned N> struct priority_tag : priority_tag < N - 1 > {};
+template<> struct priority_tag<0> {};
+
+// taken from ranges-v3
+template<typename T>
+struct static_const
+{
+    static constexpr T value{};
+};
+
+template<typename T>
+constexpr T static_const<T>::value;
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/meta/type_traits.hpp>
+
+
+#include <ciso646> // not
+#include <limits> // numeric_limits
+#include <type_traits> // false_type, is_constructible, is_integral, is_same, true_type
+#include <utility> // declval
+
+// #include <nlohmann/json_fwd.hpp>
+
+// #include <nlohmann/detail/iterators/iterator_traits.hpp>
+
+
+#include <iterator> // random_access_iterator_tag
+
+// #include <nlohmann/detail/meta/void_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+template <typename ...Ts> struct make_void
+{
+    using type = void;
+};
+template <typename ...Ts> using void_t = typename make_void<Ts...>::type;
+} // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+template <typename It, typename = void>
+struct iterator_types {};
+
+template <typename It>
+struct iterator_types <
+    It,
+    void_t<typename It::difference_type, typename It::value_type, typename It::pointer,
+    typename It::reference, typename It::iterator_category >>
+{
+    using difference_type = typename It::difference_type;
+    using value_type = typename It::value_type;
+    using pointer = typename It::pointer;
+    using reference = typename It::reference;
+    using iterator_category = typename It::iterator_category;
+};
+
+// This is required as some compilers implement std::iterator_traits in a way that
+// doesn't work with SFINAE. See https://github.com/nlohmann/json/issues/1341.
+template <typename T, typename = void>
+struct iterator_traits
+{
+};
+
+template <typename T>
+struct iterator_traits < T, enable_if_t < !std::is_pointer<T>::value >>
+            : iterator_types<T>
+{
+};
+
+template <typename T>
+struct iterator_traits<T*, enable_if_t<std::is_object<T>::value>>
+{
+    using iterator_category = std::random_access_iterator_tag;
+    using value_type = T;
+    using difference_type = ptrdiff_t;
+    using pointer = T*;
+    using reference = T&;
+};
+}
+}
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+// #include <nlohmann/detail/meta/detected.hpp>
+
+
+#include <type_traits>
+
+// #include <nlohmann/detail/meta/void_t.hpp>
+
+
+// http://en.cppreference.com/w/cpp/experimental/is_detected
+namespace nlohmann
+{
+namespace detail
+{
+struct nonesuch
+{
+    nonesuch() = delete;
+    ~nonesuch() = delete;
+    nonesuch(nonesuch const&) = delete;
+    void operator=(nonesuch const&) = delete;
+};
+
+template <class Default,
+          class AlwaysVoid,
+          template <class...> class Op,
+          class... Args>
+struct detector
+{
+    using value_t = std::false_type;
+    using type = Default;
+};
+
+template <class Default, template <class...> class Op, class... Args>
+struct detector<Default, void_t<Op<Args...>>, Op, Args...>
+{
+    using value_t = std::true_type;
+    using type = Op<Args...>;
+};
+
+template <template <class...> class Op, class... Args>
+using is_detected = typename detector<nonesuch, void, Op, Args...>::value_t;
+
+template <template <class...> class Op, class... Args>
+using detected_t = typename detector<nonesuch, void, Op, Args...>::type;
+
+template <class Default, template <class...> class Op, class... Args>
+using detected_or = detector<Default, void, Op, Args...>;
+
+template <class Default, template <class...> class Op, class... Args>
+using detected_or_t = typename detected_or<Default, Op, Args...>::type;
+
+template <class Expected, template <class...> class Op, class... Args>
+using is_detected_exact = std::is_same<Expected, detected_t<Op, Args...>>;
+
+template <class To, template <class...> class Op, class... Args>
+using is_detected_convertible =
+    std::is_convertible<detected_t<Op, Args...>, To>;
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+
+namespace nlohmann
+{
+/*!
+@brief detail namespace with internal helper functions
+
+This namespace collects functions that should not be exposed,
+implementations of some @ref basic_json methods, and meta-programming helpers.
+
+@since version 2.1.0
+*/
+namespace detail
+{
+/////////////
+// helpers //
+/////////////
+
+// Note to maintainers:
+//
+// Every trait in this file expects a non CV-qualified type.
+// The only exceptions are in the 'aliases for detected' section
+// (i.e. those of the form: decltype(T::member_function(std::declval<T>())))
+//
+// In this case, T has to be properly CV-qualified to constraint the function arguments
+// (e.g. to_json(BasicJsonType&, const T&))
+
+template<typename> struct is_basic_json : std::false_type {};
+
+NLOHMANN_BASIC_JSON_TPL_DECLARATION
+struct is_basic_json<NLOHMANN_BASIC_JSON_TPL> : std::true_type {};
+
+//////////////////////////
+// aliases for detected //
+//////////////////////////
+
+template <typename T>
+using mapped_type_t = typename T::mapped_type;
+
+template <typename T>
+using key_type_t = typename T::key_type;
+
+template <typename T>
+using value_type_t = typename T::value_type;
+
+template <typename T>
+using difference_type_t = typename T::difference_type;
+
+template <typename T>
+using pointer_t = typename T::pointer;
+
+template <typename T>
+using reference_t = typename T::reference;
+
+template <typename T>
+using iterator_category_t = typename T::iterator_category;
+
+template <typename T>
+using iterator_t = typename T::iterator;
+
+template <typename T, typename... Args>
+using to_json_function = decltype(T::to_json(std::declval<Args>()...));
+
+template <typename T, typename... Args>
+using from_json_function = decltype(T::from_json(std::declval<Args>()...));
+
+template <typename T, typename U>
+using get_template_function = decltype(std::declval<T>().template get<U>());
+
+// trait checking if JSONSerializer<T>::from_json(json const&, udt&) exists
+template <typename BasicJsonType, typename T, typename = void>
+struct has_from_json : std::false_type {};
+
+template <typename BasicJsonType, typename T>
+struct has_from_json<BasicJsonType, T,
+           enable_if_t<not is_basic_json<T>::value>>
+{
+    using serializer = typename BasicJsonType::template json_serializer<T, void>;
+
+    static constexpr bool value =
+        is_detected_exact<void, from_json_function, serializer,
+        const BasicJsonType&, T&>::value;
+};
+
+// This trait checks if JSONSerializer<T>::from_json(json const&) exists
+// this overload is used for non-default-constructible user-defined-types
+template <typename BasicJsonType, typename T, typename = void>
+struct has_non_default_from_json : std::false_type {};
+
+template<typename BasicJsonType, typename T>
+struct has_non_default_from_json<BasicJsonType, T, enable_if_t<not is_basic_json<T>::value>>
+{
+    using serializer = typename BasicJsonType::template json_serializer<T, void>;
+
+    static constexpr bool value =
+        is_detected_exact<T, from_json_function, serializer,
+        const BasicJsonType&>::value;
+};
+
+// This trait checks if BasicJsonType::json_serializer<T>::to_json exists
+// Do not evaluate the trait when T is a basic_json type, to avoid template instantiation infinite recursion.
+template <typename BasicJsonType, typename T, typename = void>
+struct has_to_json : std::false_type {};
+
+template <typename BasicJsonType, typename T>
+struct has_to_json<BasicJsonType, T, enable_if_t<not is_basic_json<T>::value>>
+{
+    using serializer = typename BasicJsonType::template json_serializer<T, void>;
+
+    static constexpr bool value =
+        is_detected_exact<void, to_json_function, serializer, BasicJsonType&,
+        T>::value;
+};
+
+
+///////////////////
+// is_ functions //
+///////////////////
+
+template <typename T, typename = void>
+struct is_iterator_traits : std::false_type {};
+
+template <typename T>
+struct is_iterator_traits<iterator_traits<T>>
+{
+  private:
+    using traits = iterator_traits<T>;
+
+  public:
+    static constexpr auto value =
+        is_detected<value_type_t, traits>::value &&
+        is_detected<difference_type_t, traits>::value &&
+        is_detected<pointer_t, traits>::value &&
+        is_detected<iterator_category_t, traits>::value &&
+        is_detected<reference_t, traits>::value;
+};
+
+// source: https://stackoverflow.com/a/37193089/4116453
+
+template <typename T, typename = void>
+struct is_complete_type : std::false_type {};
+
+template <typename T>
+struct is_complete_type<T, decltype(void(sizeof(T)))> : std::true_type {};
+
+template <typename BasicJsonType, typename CompatibleObjectType,
+          typename = void>
+struct is_compatible_object_type_impl : std::false_type {};
+
+template <typename BasicJsonType, typename CompatibleObjectType>
+struct is_compatible_object_type_impl <
+    BasicJsonType, CompatibleObjectType,
+    enable_if_t<is_detected<mapped_type_t, CompatibleObjectType>::value and
+    is_detected<key_type_t, CompatibleObjectType>::value >>
+{
+
+    using object_t = typename BasicJsonType::object_t;
+
+    // macOS's is_constructible does not play well with nonesuch...
+    static constexpr bool value =
+        std::is_constructible<typename object_t::key_type,
+        typename CompatibleObjectType::key_type>::value and
+        std::is_constructible<typename object_t::mapped_type,
+        typename CompatibleObjectType::mapped_type>::value;
+};
+
+template <typename BasicJsonType, typename CompatibleObjectType>
+struct is_compatible_object_type
+    : is_compatible_object_type_impl<BasicJsonType, CompatibleObjectType> {};
+
+template <typename BasicJsonType, typename ConstructibleObjectType,
+          typename = void>
+struct is_constructible_object_type_impl : std::false_type {};
+
+template <typename BasicJsonType, typename ConstructibleObjectType>
+struct is_constructible_object_type_impl <
+    BasicJsonType, ConstructibleObjectType,
+    enable_if_t<is_detected<mapped_type_t, ConstructibleObjectType>::value and
+    is_detected<key_type_t, ConstructibleObjectType>::value >>
+{
+    using object_t = typename BasicJsonType::object_t;
+
+    static constexpr bool value =
+        (std::is_constructible<typename ConstructibleObjectType::key_type, typename object_t::key_type>::value and
+         std::is_same<typename object_t::mapped_type, typename ConstructibleObjectType::mapped_type>::value) or
+        (has_from_json<BasicJsonType, typename ConstructibleObjectType::mapped_type>::value or
+         has_non_default_from_json<BasicJsonType, typename ConstructibleObjectType::mapped_type >::value);
+};
+
+template <typename BasicJsonType, typename ConstructibleObjectType>
+struct is_constructible_object_type
+    : is_constructible_object_type_impl<BasicJsonType,
+      ConstructibleObjectType> {};
+
+template <typename BasicJsonType, typename CompatibleStringType,
+          typename = void>
+struct is_compatible_string_type_impl : std::false_type {};
+
+template <typename BasicJsonType, typename CompatibleStringType>
+struct is_compatible_string_type_impl <
+    BasicJsonType, CompatibleStringType,
+    enable_if_t<is_detected_exact<typename BasicJsonType::string_t::value_type,
+    value_type_t, CompatibleStringType>::value >>
+{
+    static constexpr auto value =
+        std::is_constructible<typename BasicJsonType::string_t, CompatibleStringType>::value;
+};
+
+template <typename BasicJsonType, typename ConstructibleStringType>
+struct is_compatible_string_type
+    : is_compatible_string_type_impl<BasicJsonType, ConstructibleStringType> {};
+
+template <typename BasicJsonType, typename ConstructibleStringType,
+          typename = void>
+struct is_constructible_string_type_impl : std::false_type {};
+
+template <typename BasicJsonType, typename ConstructibleStringType>
+struct is_constructible_string_type_impl <
+    BasicJsonType, ConstructibleStringType,
+    enable_if_t<is_detected_exact<typename BasicJsonType::string_t::value_type,
+    value_type_t, ConstructibleStringType>::value >>
+{
+    static constexpr auto value =
+        std::is_constructible<ConstructibleStringType,
+        typename BasicJsonType::string_t>::value;
+};
+
+template <typename BasicJsonType, typename ConstructibleStringType>
+struct is_constructible_string_type
+    : is_constructible_string_type_impl<BasicJsonType, ConstructibleStringType> {};
+
+template <typename BasicJsonType, typename CompatibleArrayType, typename = void>
+struct is_compatible_array_type_impl : std::false_type {};
+
+template <typename BasicJsonType, typename CompatibleArrayType>
+struct is_compatible_array_type_impl <
+    BasicJsonType, CompatibleArrayType,
+    enable_if_t<is_detected<value_type_t, CompatibleArrayType>::value and
+    is_detected<iterator_t, CompatibleArrayType>::value and
+// This is needed because json_reverse_iterator has a ::iterator type...
+// Therefore it is detected as a CompatibleArrayType.
+// The real fix would be to have an Iterable concept.
+    not is_iterator_traits<
+    iterator_traits<CompatibleArrayType>>::value >>
+{
+    static constexpr bool value =
+        std::is_constructible<BasicJsonType,
+        typename CompatibleArrayType::value_type>::value;
+};
+
+template <typename BasicJsonType, typename CompatibleArrayType>
+struct is_compatible_array_type
+    : is_compatible_array_type_impl<BasicJsonType, CompatibleArrayType> {};
+
+template <typename BasicJsonType, typename ConstructibleArrayType, typename = void>
+struct is_constructible_array_type_impl : std::false_type {};
+
+template <typename BasicJsonType, typename ConstructibleArrayType>
+struct is_constructible_array_type_impl <
+    BasicJsonType, ConstructibleArrayType,
+    enable_if_t<std::is_same<ConstructibleArrayType,
+    typename BasicJsonType::value_type>::value >>
+            : std::true_type {};
+
+template <typename BasicJsonType, typename ConstructibleArrayType>
+struct is_constructible_array_type_impl <
+    BasicJsonType, ConstructibleArrayType,
+    enable_if_t<not std::is_same<ConstructibleArrayType,
+    typename BasicJsonType::value_type>::value and
+    is_detected<value_type_t, ConstructibleArrayType>::value and
+    is_detected<iterator_t, ConstructibleArrayType>::value and
+    is_complete_type<
+    detected_t<value_type_t, ConstructibleArrayType>>::value >>
+{
+    static constexpr bool value =
+        // This is needed because json_reverse_iterator has a ::iterator type,
+        // furthermore, std::back_insert_iterator (and other iterators) have a base class `iterator`...
+        // Therefore it is detected as a ConstructibleArrayType.
+        // The real fix would be to have an Iterable concept.
+        not is_iterator_traits <
+        iterator_traits<ConstructibleArrayType >>::value and
+
+        (std::is_same<typename ConstructibleArrayType::value_type, typename BasicJsonType::array_t::value_type>::value or
+         has_from_json<BasicJsonType,
+         typename ConstructibleArrayType::value_type>::value or
+         has_non_default_from_json <
+         BasicJsonType, typename ConstructibleArrayType::value_type >::value);
+};
+
+template <typename BasicJsonType, typename ConstructibleArrayType>
+struct is_constructible_array_type
+    : is_constructible_array_type_impl<BasicJsonType, ConstructibleArrayType> {};
+
+template <typename RealIntegerType, typename CompatibleNumberIntegerType,
+          typename = void>
+struct is_compatible_integer_type_impl : std::false_type {};
+
+template <typename RealIntegerType, typename CompatibleNumberIntegerType>
+struct is_compatible_integer_type_impl <
+    RealIntegerType, CompatibleNumberIntegerType,
+    enable_if_t<std::is_integral<RealIntegerType>::value and
+    std::is_integral<CompatibleNumberIntegerType>::value and
+    not std::is_same<bool, CompatibleNumberIntegerType>::value >>
+{
+    // is there an assert somewhere on overflows?
+    using RealLimits = std::numeric_limits<RealIntegerType>;
+    using CompatibleLimits = std::numeric_limits<CompatibleNumberIntegerType>;
+
+    static constexpr auto value =
+        std::is_constructible<RealIntegerType,
+        CompatibleNumberIntegerType>::value and
+        CompatibleLimits::is_integer and
+        RealLimits::is_signed == CompatibleLimits::is_signed;
+};
+
+template <typename RealIntegerType, typename CompatibleNumberIntegerType>
+struct is_compatible_integer_type
+    : is_compatible_integer_type_impl<RealIntegerType,
+      CompatibleNumberIntegerType> {};
+
+template <typename BasicJsonType, typename CompatibleType, typename = void>
+struct is_compatible_type_impl: std::false_type {};
+
+template <typename BasicJsonType, typename CompatibleType>
+struct is_compatible_type_impl <
+    BasicJsonType, CompatibleType,
+    enable_if_t<is_complete_type<CompatibleType>::value >>
+{
+    static constexpr bool value =
+        has_to_json<BasicJsonType, CompatibleType>::value;
+};
+
+template <typename BasicJsonType, typename CompatibleType>
+struct is_compatible_type
+    : is_compatible_type_impl<BasicJsonType, CompatibleType> {};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+
+#include <exception> // exception
+#include <stdexcept> // runtime_error
+#include <string> // to_string
+
+// #include <nlohmann/detail/input/position_t.hpp>
+
+
+#include <cstddef> // size_t
+
+namespace nlohmann
+{
+namespace detail
+{
+/// struct to capture the start position of the current token
+struct position_t
+{
+    /// the total number of characters read
+    std::size_t chars_read_total = 0;
+    /// the number of characters read in the current line
+    std::size_t chars_read_current_line = 0;
+    /// the number of lines read
+    std::size_t lines_read = 0;
+
+    /// conversion to size_t to preserve SAX interface
+    constexpr operator size_t() const
+    {
+        return chars_read_total;
+    }
+};
+
+}
+}
+
+
+namespace nlohmann
+{
+namespace detail
+{
+////////////////
+// exceptions //
+////////////////
+
+/*!
+@brief general exception of the @ref basic_json class
+
+This class is an extension of `std::exception` objects with a member @a id for
+exception ids. It is used as the base class for all exceptions thrown by the
+@ref basic_json class. This class can hence be used as "wildcard" to catch
+exceptions.
+
+Subclasses:
+- @ref parse_error for exceptions indicating a parse error
+- @ref invalid_iterator for exceptions indicating errors with iterators
+- @ref type_error for exceptions indicating executing a member function with
+                  a wrong type
+- @ref out_of_range for exceptions indicating access out of the defined range
+- @ref other_error for exceptions indicating other library errors
+
+@internal
+@note To have nothrow-copy-constructible exceptions, we internally use
+      `std::runtime_error` which can cope with arbitrary-length error messages.
+      Intermediate strings are built with static functions and then passed to
+      the actual constructor.
+@endinternal
+
+@liveexample{The following code shows how arbitrary library exceptions can be
+caught.,exception}
+
+@since version 3.0.0
+*/
+class exception : public std::exception
+{
+  public:
+    /// returns the explanatory string
+    const char* what() const noexcept override
+    {
+        return m.what();
+    }
+
+    /// the id of the exception
+    const int id;
+
+  protected:
+    exception(int id_, const char* what_arg) : id(id_), m(what_arg) {}
+
+    static std::string name(const std::string& ename, int id_)
+    {
+        return "[json.exception." + ename + "." + std::to_string(id_) + "] ";
+    }
+
+  private:
+    /// an exception object as storage for error messages
+    std::runtime_error m;
+};
+
+/*!
+@brief exception indicating a parse error
+
+This exception is thrown by the library when a parse error occurs. Parse errors
+can occur during the deserialization of JSON text, CBOR, MessagePack, as well
+as when using JSON Patch.
+
+Member @a byte holds the byte index of the last read character in the input
+file.
+
+Exceptions have ids 1xx.
+
+name / id                      | example message | description
+------------------------------ | --------------- | -------------------------
+json.exception.parse_error.101 | parse error at 2: unexpected end of input; expected string literal | This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member @a byte indicates the error position.
+json.exception.parse_error.102 | parse error at 14: missing or wrong low surrogate | JSON uses the `\uxxxx` format to describe Unicode characters. Code points above above 0xFFFF are split into two `\uxxxx` entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point.
+json.exception.parse_error.103 | parse error: code points above 0x10FFFF are invalid | Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid.
+json.exception.parse_error.104 | parse error: JSON patch must be an array of objects | [RFC 6902](https://tools.ietf.org/html/rfc6902) requires a JSON Patch document to be a JSON document that represents an array of objects.
+json.exception.parse_error.105 | parse error: operation must have string member 'op' | An operation of a JSON Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors.
+json.exception.parse_error.106 | parse error: array index '01' must not begin with '0' | An array index in a JSON Pointer ([RFC 6901](https://tools.ietf.org/html/rfc6901)) may be `0` or any number without a leading `0`.
+json.exception.parse_error.107 | parse error: JSON pointer must be empty or begin with '/' - was: 'foo' | A JSON Pointer must be a Unicode string containing a sequence of zero or more reference tokens, each prefixed by a `/` character.
+json.exception.parse_error.108 | parse error: escape character '~' must be followed with '0' or '1' | In a JSON Pointer, only `~0` and `~1` are valid escape sequences.
+json.exception.parse_error.109 | parse error: array index 'one' is not a number | A JSON Pointer array index must be a number.
+json.exception.parse_error.110 | parse error at 1: cannot read 2 bytes from vector | When parsing CBOR or MessagePack, the byte vector ends before the complete value has been read.
+json.exception.parse_error.112 | parse error at 1: error reading CBOR; last byte: 0xF8 | Not all types of CBOR or MessagePack are supported. This exception occurs if an unsupported byte was read.
+json.exception.parse_error.113 | parse error at 2: expected a CBOR string; last byte: 0x98 | While parsing a map key, a value that is not a string has been read.
+json.exception.parse_error.114 | parse error: Unsupported BSON record type 0x0F | The parsing of the corresponding BSON record type is not implemented (yet).
+
+@note For an input with n bytes, 1 is the index of the first character and n+1
+      is the index of the terminating null byte or the end of file. This also
+      holds true when reading a byte vector (CBOR or MessagePack).
+
+@liveexample{The following code shows how a `parse_error` exception can be
+caught.,parse_error}
+
+@sa @ref exception for the base class of the library exceptions
+@sa @ref invalid_iterator for exceptions indicating errors with iterators
+@sa @ref type_error for exceptions indicating executing a member function with
+                    a wrong type
+@sa @ref out_of_range for exceptions indicating access out of the defined range
+@sa @ref other_error for exceptions indicating other library errors
+
+@since version 3.0.0
+*/
+class parse_error : public exception
+{
+  public:
+    /*!
+    @brief create a parse error exception
+    @param[in] id_       the id of the exception
+    @param[in] position  the position where the error occurred (or with
+                         chars_read_total=0 if the position cannot be
+                         determined)
+    @param[in] what_arg  the explanatory string
+    @return parse_error object
+    */
+    static parse_error create(int id_, const position_t& pos, const std::string& what_arg)
+    {
+        std::string w = exception::name("parse_error", id_) + "parse error" +
+                        position_string(pos) + ": " + what_arg;
+        return parse_error(id_, pos.chars_read_total, w.c_str());
+    }
+
+    static parse_error create(int id_, std::size_t byte_, const std::string& what_arg)
+    {
+        std::string w = exception::name("parse_error", id_) + "parse error" +
+                        (byte_ != 0 ? (" at byte " + std::to_string(byte_)) : "") +
+                        ": " + what_arg;
+        return parse_error(id_, byte_, w.c_str());
+    }
+
+    /*!
+    @brief byte index of the parse error
+
+    The byte index of the last read character in the input file.
+
+    @note For an input with n bytes, 1 is the index of the first character and
+          n+1 is the index of the terminating null byte or the end of file.
+          This also holds true when reading a byte vector (CBOR or MessagePack).
+    */
+    const std::size_t byte;
+
+  private:
+    parse_error(int id_, std::size_t byte_, const char* what_arg)
+        : exception(id_, what_arg), byte(byte_) {}
+
+    static std::string position_string(const position_t& pos)
+    {
+        return " at line " + std::to_string(pos.lines_read + 1) +
+               ", column " + std::to_string(pos.chars_read_current_line);
+    }
+};
+
+/*!
+@brief exception indicating errors with iterators
+
+This exception is thrown if iterators passed to a library function do not match
+the expected semantics.
+
+Exceptions have ids 2xx.
+
+name / id                           | example message | description
+----------------------------------- | --------------- | -------------------------
+json.exception.invalid_iterator.201 | iterators are not compatible | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
+json.exception.invalid_iterator.202 | iterator does not fit current value | In an erase or insert function, the passed iterator @a pos does not belong to the JSON value for which the function was called. It hence does not define a valid position for the deletion/insertion.
+json.exception.invalid_iterator.203 | iterators do not fit current value | Either iterator passed to function @ref erase(IteratorType first, IteratorType last) does not belong to the JSON value from which values shall be erased. It hence does not define a valid range to delete values from.
+json.exception.invalid_iterator.204 | iterators out of range | When an iterator range for a primitive type (number, boolean, or string) is passed to a constructor or an erase function, this range has to be exactly (@ref begin(), @ref end()), because this is the only way the single stored value is expressed. All other ranges are invalid.
+json.exception.invalid_iterator.205 | iterator out of range | When an iterator for a primitive type (number, boolean, or string) is passed to an erase function, the iterator has to be the @ref begin() iterator, because it is the only way to address the stored value. All other iterators are invalid.
+json.exception.invalid_iterator.206 | cannot construct with iterators from null | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) belong to a JSON null value and hence to not define a valid range.
+json.exception.invalid_iterator.207 | cannot use key() for non-object iterators | The key() member function can only be used on iterators belonging to a JSON object, because other types do not have a concept of a key.
+json.exception.invalid_iterator.208 | cannot use operator[] for object iterators | The operator[] to specify a concrete offset cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
+json.exception.invalid_iterator.209 | cannot use offsets with object iterators | The offset operators (+, -, +=, -=) cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
+json.exception.invalid_iterator.210 | iterators do not fit | The iterator range passed to the insert function are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
+json.exception.invalid_iterator.211 | passed iterators may not belong to container | The iterator range passed to the insert function must not be a subrange of the container to insert to.
+json.exception.invalid_iterator.212 | cannot compare iterators of different containers | When two iterators are compared, they must belong to the same container.
+json.exception.invalid_iterator.213 | cannot compare order of object iterators | The order of object iterators cannot be compared, because JSON objects are unordered.
+json.exception.invalid_iterator.214 | cannot get value | Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to @ref begin().
+
+@liveexample{The following code shows how an `invalid_iterator` exception can be
+caught.,invalid_iterator}
+
+@sa @ref exception for the base class of the library exceptions
+@sa @ref parse_error for exceptions indicating a parse error
+@sa @ref type_error for exceptions indicating executing a member function with
+                    a wrong type
+@sa @ref out_of_range for exceptions indicating access out of the defined range
+@sa @ref other_error for exceptions indicating other library errors
+
+@since version 3.0.0
+*/
+class invalid_iterator : public exception
+{
+  public:
+    static invalid_iterator create(int id_, const std::string& what_arg)
+    {
+        std::string w = exception::name("invalid_iterator", id_) + what_arg;
+        return invalid_iterator(id_, w.c_str());
+    }
+
+  private:
+    invalid_iterator(int id_, const char* what_arg)
+        : exception(id_, what_arg) {}
+};
+
+/*!
+@brief exception indicating executing a member function with a wrong type
+
+This exception is thrown in case of a type error; that is, a library function is
+executed on a JSON value whose type does not match the expected semantics.
+
+Exceptions have ids 3xx.
+
+name / id                     | example message | description
+----------------------------- | --------------- | -------------------------
+json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead.
+json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types.
+json.exception.type_error.303 | incompatible ReferenceType for get_ref, actual type is object | To retrieve a reference to a value stored in a @ref basic_json object with @ref get_ref, the type of the reference must match the value type. For instance, for a JSON array, the @a ReferenceType must be @ref array_t&.
+json.exception.type_error.304 | cannot use at() with string | The @ref at() member functions can only be executed for certain JSON types.
+json.exception.type_error.305 | cannot use operator[] with string | The @ref operator[] member functions can only be executed for certain JSON types.
+json.exception.type_error.306 | cannot use value() with string | The @ref value() member functions can only be executed for certain JSON types.
+json.exception.type_error.307 | cannot use erase() with string | The @ref erase() member functions can only be executed for certain JSON types.
+json.exception.type_error.308 | cannot use push_back() with string | The @ref push_back() and @ref operator+= member functions can only be executed for certain JSON types.
+json.exception.type_error.309 | cannot use insert() with | The @ref insert() member functions can only be executed for certain JSON types.
+json.exception.type_error.310 | cannot use swap() with number | The @ref swap() member functions can only be executed for certain JSON types.
+json.exception.type_error.311 | cannot use emplace_back() with string | The @ref emplace_back() member function can only be executed for certain JSON types.
+json.exception.type_error.312 | cannot use update() with string | The @ref update() member functions can only be executed for certain JSON types.
+json.exception.type_error.313 | invalid value to unflatten | The @ref unflatten function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well defined.
+json.exception.type_error.314 | only objects can be unflattened | The @ref unflatten function only works for an object whose keys are JSON Pointers.
+json.exception.type_error.315 | values in object must be primitive | The @ref unflatten function only works for an object whose keys are JSON Pointers and whose values are primitive.
+json.exception.type_error.316 | invalid UTF-8 byte at index 10: 0x7E | The @ref dump function only works with UTF-8 encoded strings; that is, if you assign a `std::string` to a JSON value, make sure it is UTF-8 encoded. |
+json.exception.type_error.317 | JSON value cannot be serialized to requested format | The dynamic type of the object cannot be represented in the requested serialization format (e.g. a raw `true` or `null` JSON object cannot be serialized to BSON) |
+
+@liveexample{The following code shows how a `type_error` exception can be
+caught.,type_error}
+
+@sa @ref exception for the base class of the library exceptions
+@sa @ref parse_error for exceptions indicating a parse error
+@sa @ref invalid_iterator for exceptions indicating errors with iterators
+@sa @ref out_of_range for exceptions indicating access out of the defined range
+@sa @ref other_error for exceptions indicating other library errors
+
+@since version 3.0.0
+*/
+class type_error : public exception
+{
+  public:
+    static type_error create(int id_, const std::string& what_arg)
+    {
+        std::string w = exception::name("type_error", id_) + what_arg;
+        return type_error(id_, w.c_str());
+    }
+
+  private:
+    type_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
+};
+
+/*!
+@brief exception indicating access out of the defined range
+
+This exception is thrown in case a library function is called on an input
+parameter that exceeds the expected range, for instance in case of array
+indices or nonexisting object keys.
+
+Exceptions have ids 4xx.
+
+name / id                       | example message | description
+------------------------------- | --------------- | -------------------------
+json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1.
+json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.
+json.exception.out_of_range.403 | key 'foo' not found | The provided key was not found in the JSON object.
+json.exception.out_of_range.404 | unresolved reference token 'foo' | A reference token in a JSON Pointer could not be resolved.
+json.exception.out_of_range.405 | JSON pointer has no parent | The JSON Patch operations 'remove' and 'add' can not be applied to the root element of the JSON value.
+json.exception.out_of_range.406 | number overflow parsing '10E1000' | A parsed number could not be stored as without changing it to NaN or INF.
+json.exception.out_of_range.407 | number overflow serializing '9223372036854775808' | UBJSON and BSON only support integer numbers up to 9223372036854775807. |
+json.exception.out_of_range.408 | excessive array size: 8658170730974374167 | The size (following `#`) of an UBJSON array or object exceeds the maximal capacity. |
+json.exception.out_of_range.409 | BSON key cannot contain code point U+0000 (at byte 2) | Key identifiers to be serialized to BSON cannot contain code point U+0000, since the key is stored as zero-terminated c-string |
+
+@liveexample{The following code shows how an `out_of_range` exception can be
+caught.,out_of_range}
+
+@sa @ref exception for the base class of the library exceptions
+@sa @ref parse_error for exceptions indicating a parse error
+@sa @ref invalid_iterator for exceptions indicating errors with iterators
+@sa @ref type_error for exceptions indicating executing a member function with
+                    a wrong type
+@sa @ref other_error for exceptions indicating other library errors
+
+@since version 3.0.0
+*/
+class out_of_range : public exception
+{
+  public:
+    static out_of_range create(int id_, const std::string& what_arg)
+    {
+        std::string w = exception::name("out_of_range", id_) + what_arg;
+        return out_of_range(id_, w.c_str());
+    }
+
+  private:
+    out_of_range(int id_, const char* what_arg) : exception(id_, what_arg) {}
+};
+
+/*!
+@brief exception indicating other library errors
+
+This exception is thrown in case of errors that cannot be classified with the
+other exception types.
+
+Exceptions have ids 5xx.
+
+name / id                      | example message | description
+------------------------------ | --------------- | -------------------------
+json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.
+
+@sa @ref exception for the base class of the library exceptions
+@sa @ref parse_error for exceptions indicating a parse error
+@sa @ref invalid_iterator for exceptions indicating errors with iterators
+@sa @ref type_error for exceptions indicating executing a member function with
+                    a wrong type
+@sa @ref out_of_range for exceptions indicating access out of the defined range
+
+@liveexample{The following code shows how an `other_error` exception can be
+caught.,other_error}
+
+@since version 3.0.0
+*/
+class other_error : public exception
+{
+  public:
+    static other_error create(int id_, const std::string& what_arg)
+    {
+        std::string w = exception::name("other_error", id_) + what_arg;
+        return other_error(id_, w.c_str());
+    }
+
+  private:
+    other_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+#include <array> // array
+#include <ciso646> // and
+#include <cstddef> // size_t
+#include <cstdint> // uint8_t
+
+namespace nlohmann
+{
+namespace detail
+{
+///////////////////////////
+// JSON type enumeration //
+///////////////////////////
+
+/*!
+@brief the JSON type enumeration
+
+This enumeration collects the different JSON types. It is internally used to
+distinguish the stored values, and the functions @ref basic_json::is_null(),
+@ref basic_json::is_object(), @ref basic_json::is_array(),
+@ref basic_json::is_string(), @ref basic_json::is_boolean(),
+@ref basic_json::is_number() (with @ref basic_json::is_number_integer(),
+@ref basic_json::is_number_unsigned(), and @ref basic_json::is_number_float()),
+@ref basic_json::is_discarded(), @ref basic_json::is_primitive(), and
+@ref basic_json::is_structured() rely on it.
+
+@note There are three enumeration entries (number_integer, number_unsigned, and
+number_float), because the library distinguishes these three types for numbers:
+@ref basic_json::number_unsigned_t is used for unsigned integers,
+@ref basic_json::number_integer_t is used for signed integers, and
+@ref basic_json::number_float_t is used for floating-point numbers or to
+approximate integers which do not fit in the limits of their respective type.
+
+@sa @ref basic_json::basic_json(const value_t value_type) -- create a JSON
+value with the default value for a given type
+
+@since version 1.0.0
+*/
+enum class value_t : std::uint8_t
+{
+    null,             ///< null value
+    object,           ///< object (unordered set of name/value pairs)
+    array,            ///< array (ordered collection of values)
+    string,           ///< string value
+    boolean,          ///< boolean value
+    number_integer,   ///< number value (signed integer)
+    number_unsigned,  ///< number value (unsigned integer)
+    number_float,     ///< number value (floating-point)
+    discarded         ///< discarded by the the parser callback function
+};
+
+/*!
+@brief comparison operator for JSON types
+
+Returns an ordering that is similar to Python:
+- order: null < boolean < number < object < array < string
+- furthermore, each type is not smaller than itself
+- discarded values are not comparable
+
+@since version 1.0.0
+*/
+inline bool operator<(const value_t lhs, const value_t rhs) noexcept
+{
+    static constexpr std::array<std::uint8_t, 8> order = {{
+            0 /* null */, 3 /* object */, 4 /* array */, 5 /* string */,
+            1 /* boolean */, 2 /* integer */, 2 /* unsigned */, 2 /* float */
+        }
+    };
+
+    const auto l_index = static_cast<std::size_t>(lhs);
+    const auto r_index = static_cast<std::size_t>(rhs);
+    return l_index < order.size() and r_index < order.size() and order[l_index] < order[r_index];
+}
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/conversions/from_json.hpp>
+
+
+#include <algorithm> // transform
+#include <array> // array
+#include <ciso646> // and, not
+#include <forward_list> // forward_list
+#include <iterator> // inserter, front_inserter, end
+#include <map> // map
+#include <string> // string
+#include <tuple> // tuple, make_tuple
+#include <type_traits> // is_arithmetic, is_same, is_enum, underlying_type, is_convertible
+#include <unordered_map> // unordered_map
+#include <utility> // pair, declval
+#include <valarray> // valarray
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+// #include <nlohmann/detail/meta/type_traits.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+template<typename BasicJsonType>
+void from_json(const BasicJsonType& j, typename std::nullptr_t& n)
+{
+    if (JSON_UNLIKELY(not j.is_null()))
+    {
+        JSON_THROW(type_error::create(302, "type must be null, but is " + std::string(j.type_name())));
+    }
+    n = nullptr;
+}
+
+// overloads for basic_json template parameters
+template<typename BasicJsonType, typename ArithmeticType,
+         enable_if_t<std::is_arithmetic<ArithmeticType>::value and
+                     not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
+                     int> = 0>
+void get_arithmetic_value(const BasicJsonType& j, ArithmeticType& val)
+{
+    switch (static_cast<value_t>(j))
+    {
+        case value_t::number_unsigned:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
+            break;
+        }
+        case value_t::number_integer:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
+            break;
+        }
+        case value_t::number_float:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
+            break;
+        }
+
+        default:
+            JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name())));
+    }
+}
+
+template<typename BasicJsonType>
+void from_json(const BasicJsonType& j, typename BasicJsonType::boolean_t& b)
+{
+    if (JSON_UNLIKELY(not j.is_boolean()))
+    {
+        JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(j.type_name())));
+    }
+    b = *j.template get_ptr<const typename BasicJsonType::boolean_t*>();
+}
+
+template<typename BasicJsonType>
+void from_json(const BasicJsonType& j, typename BasicJsonType::string_t& s)
+{
+    if (JSON_UNLIKELY(not j.is_string()))
+    {
+        JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name())));
+    }
+    s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
+}
+
+template <
+    typename BasicJsonType, typename ConstructibleStringType,
+    enable_if_t <
+        is_constructible_string_type<BasicJsonType, ConstructibleStringType>::value and
+        not std::is_same<typename BasicJsonType::string_t,
+                         ConstructibleStringType>::value,
+        int > = 0 >
+void from_json(const BasicJsonType& j, ConstructibleStringType& s)
+{
+    if (JSON_UNLIKELY(not j.is_string()))
+    {
+        JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name())));
+    }
+
+    s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
+}
+
+template<typename BasicJsonType>
+void from_json(const BasicJsonType& j, typename BasicJsonType::number_float_t& val)
+{
+    get_arithmetic_value(j, val);
+}
+
+template<typename BasicJsonType>
+void from_json(const BasicJsonType& j, typename BasicJsonType::number_unsigned_t& val)
+{
+    get_arithmetic_value(j, val);
+}
+
+template<typename BasicJsonType>
+void from_json(const BasicJsonType& j, typename BasicJsonType::number_integer_t& val)
+{
+    get_arithmetic_value(j, val);
+}
+
+template<typename BasicJsonType, typename EnumType,
+         enable_if_t<std::is_enum<EnumType>::value, int> = 0>
+void from_json(const BasicJsonType& j, EnumType& e)
+{
+    typename std::underlying_type<EnumType>::type val;
+    get_arithmetic_value(j, val);
+    e = static_cast<EnumType>(val);
+}
+
+// forward_list doesn't have an insert method
+template<typename BasicJsonType, typename T, typename Allocator,
+         enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
+void from_json(const BasicJsonType& j, std::forward_list<T, Allocator>& l)
+{
+    if (JSON_UNLIKELY(not j.is_array()))
+    {
+        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
+    }
+    std::transform(j.rbegin(), j.rend(),
+                   std::front_inserter(l), [](const BasicJsonType & i)
+    {
+        return i.template get<T>();
+    });
+}
+
+// valarray doesn't have an insert method
+template<typename BasicJsonType, typename T,
+         enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0>
+void from_json(const BasicJsonType& j, std::valarray<T>& l)
+{
+    if (JSON_UNLIKELY(not j.is_array()))
+    {
+        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
+    }
+    l.resize(j.size());
+    std::copy(j.m_value.array->begin(), j.m_value.array->end(), std::begin(l));
+}
+
+template<typename BasicJsonType>
+void from_json_array_impl(const BasicJsonType& j, typename BasicJsonType::array_t& arr, priority_tag<3> /*unused*/)
+{
+    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
+}
+
+template <typename BasicJsonType, typename T, std::size_t N>
+auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
+                          priority_tag<2> /*unused*/)
+-> decltype(j.template get<T>(), void())
+{
+    for (std::size_t i = 0; i < N; ++i)
+    {
+        arr[i] = j.at(i).template get<T>();
+    }
+}
+
+template<typename BasicJsonType, typename ConstructibleArrayType>
+auto from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr, priority_tag<1> /*unused*/)
+-> decltype(
+    arr.reserve(std::declval<typename ConstructibleArrayType::size_type>()),
+    j.template get<typename ConstructibleArrayType::value_type>(),
+    void())
+{
+    using std::end;
+
+    arr.reserve(j.size());
+    std::transform(j.begin(), j.end(),
+                   std::inserter(arr, end(arr)), [](const BasicJsonType & i)
+    {
+        // get<BasicJsonType>() returns *this, this won't call a from_json
+        // method when value_type is BasicJsonType
+        return i.template get<typename ConstructibleArrayType::value_type>();
+    });
+}
+
+template <typename BasicJsonType, typename ConstructibleArrayType>
+void from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr,
+                          priority_tag<0> /*unused*/)
+{
+    using std::end;
+
+    std::transform(
+        j.begin(), j.end(), std::inserter(arr, end(arr)),
+        [](const BasicJsonType & i)
+    {
+        // get<BasicJsonType>() returns *this, this won't call a from_json
+        // method when value_type is BasicJsonType
+        return i.template get<typename ConstructibleArrayType::value_type>();
+    });
+}
+
+template <typename BasicJsonType, typename ConstructibleArrayType,
+          enable_if_t <
+              is_constructible_array_type<BasicJsonType, ConstructibleArrayType>::value and
+              not is_constructible_object_type<BasicJsonType, ConstructibleArrayType>::value and
+              not is_constructible_string_type<BasicJsonType, ConstructibleArrayType>::value and
+              not is_basic_json<ConstructibleArrayType>::value,
+              int > = 0 >
+
+auto from_json(const BasicJsonType& j, ConstructibleArrayType& arr)
+-> decltype(from_json_array_impl(j, arr, priority_tag<3> {}),
+j.template get<typename ConstructibleArrayType::value_type>(),
+void())
+{
+    if (JSON_UNLIKELY(not j.is_array()))
+    {
+        JSON_THROW(type_error::create(302, "type must be array, but is " +
+                                      std::string(j.type_name())));
+    }
+
+    from_json_array_impl(j, arr, priority_tag<3> {});
+}
+
+template<typename BasicJsonType, typename ConstructibleObjectType,
+         enable_if_t<is_constructible_object_type<BasicJsonType, ConstructibleObjectType>::value, int> = 0>
+void from_json(const BasicJsonType& j, ConstructibleObjectType& obj)
+{
+    if (JSON_UNLIKELY(not j.is_object()))
+    {
+        JSON_THROW(type_error::create(302, "type must be object, but is " + std::string(j.type_name())));
+    }
+
+    auto inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>();
+    using value_type = typename ConstructibleObjectType::value_type;
+    std::transform(
+        inner_object->begin(), inner_object->end(),
+        std::inserter(obj, obj.begin()),
+        [](typename BasicJsonType::object_t::value_type const & p)
+    {
+        return value_type(p.first, p.second.template get<typename ConstructibleObjectType::mapped_type>());
+    });
+}
+
+// overload for arithmetic types, not chosen for basic_json template arguments
+// (BooleanType, etc..); note: Is it really necessary to provide explicit
+// overloads for boolean_t etc. in case of a custom BooleanType which is not
+// an arithmetic type?
+template<typename BasicJsonType, typename ArithmeticType,
+         enable_if_t <
+             std::is_arithmetic<ArithmeticType>::value and
+             not std::is_same<ArithmeticType, typename BasicJsonType::number_unsigned_t>::value and
+             not std::is_same<ArithmeticType, typename BasicJsonType::number_integer_t>::value and
+             not std::is_same<ArithmeticType, typename BasicJsonType::number_float_t>::value and
+             not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
+             int> = 0>
+void from_json(const BasicJsonType& j, ArithmeticType& val)
+{
+    switch (static_cast<value_t>(j))
+    {
+        case value_t::number_unsigned:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
+            break;
+        }
+        case value_t::number_integer:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
+            break;
+        }
+        case value_t::number_float:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
+            break;
+        }
+        case value_t::boolean:
+        {
+            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::boolean_t*>());
+            break;
+        }
+
+        default:
+            JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name())));
+    }
+}
+
+template<typename BasicJsonType, typename A1, typename A2>
+void from_json(const BasicJsonType& j, std::pair<A1, A2>& p)
+{
+    p = {j.at(0).template get<A1>(), j.at(1).template get<A2>()};
+}
+
+template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
+void from_json_tuple_impl(const BasicJsonType& j, Tuple& t, index_sequence<Idx...> /*unused*/)
+{
+    t = std::make_tuple(j.at(Idx).template get<typename std::tuple_element<Idx, Tuple>::type>()...);
+}
+
+template<typename BasicJsonType, typename... Args>
+void from_json(const BasicJsonType& j, std::tuple<Args...>& t)
+{
+    from_json_tuple_impl(j, t, index_sequence_for<Args...> {});
+}
+
+template <typename BasicJsonType, typename Key, typename Value, typename Compare, typename Allocator,
+          typename = enable_if_t<not std::is_constructible<
+                                     typename BasicJsonType::string_t, Key>::value>>
+void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allocator>& m)
+{
+    if (JSON_UNLIKELY(not j.is_array()))
+    {
+        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
+    }
+    for (const auto& p : j)
+    {
+        if (JSON_UNLIKELY(not p.is_array()))
+        {
+            JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name())));
+        }
+        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
+    }
+}
+
+template <typename BasicJsonType, typename Key, typename Value, typename Hash, typename KeyEqual, typename Allocator,
+          typename = enable_if_t<not std::is_constructible<
+                                     typename BasicJsonType::string_t, Key>::value>>
+void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyEqual, Allocator>& m)
+{
+    if (JSON_UNLIKELY(not j.is_array()))
+    {
+        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name())));
+    }
+    for (const auto& p : j)
+    {
+        if (JSON_UNLIKELY(not p.is_array()))
+        {
+            JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name())));
+        }
+        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
+    }
+}
+
+struct from_json_fn
+{
+    template<typename BasicJsonType, typename T>
+    auto operator()(const BasicJsonType& j, T& val) const
+    noexcept(noexcept(from_json(j, val)))
+    -> decltype(from_json(j, val), void())
+    {
+        return from_json(j, val);
+    }
+};
+}  // namespace detail
+
+/// namespace to hold default `from_json` function
+/// to see why this is required:
+/// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
+namespace
+{
+constexpr const auto& from_json = detail::static_const<detail::from_json_fn>::value;
+} // namespace
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/conversions/to_json.hpp>
+
+
+#include <ciso646> // or, and, not
+#include <iterator> // begin, end
+#include <tuple> // tuple, get
+#include <type_traits> // is_same, is_constructible, is_floating_point, is_enum, underlying_type
+#include <utility> // move, forward, declval, pair
+#include <valarray> // valarray
+#include <vector> // vector
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+// #include <nlohmann/detail/meta/type_traits.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+// #include <nlohmann/detail/iterators/iteration_proxy.hpp>
+
+
+#include <cstddef> // size_t
+#include <string> // string, to_string
+#include <iterator> // input_iterator_tag
+#include <tuple> // tuple_size, get, tuple_element
+
+// #include <nlohmann/detail/value_t.hpp>
+
+// #include <nlohmann/detail/meta/type_traits.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+template <typename IteratorType> class iteration_proxy_value
+{
+  public:
+    using difference_type = std::ptrdiff_t;
+    using value_type = iteration_proxy_value;
+    using pointer = value_type * ;
+    using reference = value_type & ;
+    using iterator_category = std::input_iterator_tag;
+
+  private:
+    /// the iterator
+    IteratorType anchor;
+    /// an index for arrays (used to create key names)
+    std::size_t array_index = 0;
+    /// last stringified array index
+    mutable std::size_t array_index_last = 0;
+    /// a string representation of the array index
+    mutable std::string array_index_str = "0";
+    /// an empty string (to return a reference for primitive values)
+    const std::string empty_str = "";
+
+  public:
+    explicit iteration_proxy_value(IteratorType it) noexcept : anchor(it) {}
+
+    /// dereference operator (needed for range-based for)
+    iteration_proxy_value& operator*()
+    {
+        return *this;
+    }
+
+    /// increment operator (needed for range-based for)
+    iteration_proxy_value& operator++()
+    {
+        ++anchor;
+        ++array_index;
+
+        return *this;
+    }
+
+    /// equality operator (needed for InputIterator)
+    bool operator==(const iteration_proxy_value& o) const noexcept
+    {
+        return anchor == o.anchor;
+    }
+
+    /// inequality operator (needed for range-based for)
+    bool operator!=(const iteration_proxy_value& o) const noexcept
+    {
+        return anchor != o.anchor;
+    }
+
+    /// return key of the iterator
+    const std::string& key() const
+    {
+        assert(anchor.m_object != nullptr);
+
+        switch (anchor.m_object->type())
+        {
+            // use integer array index as key
+            case value_t::array:
+            {
+                if (array_index != array_index_last)
+                {
+                    array_index_str = std::to_string(array_index);
+                    array_index_last = array_index;
+                }
+                return array_index_str;
+            }
+
+            // use key from the object
+            case value_t::object:
+                return anchor.key();
+
+            // use an empty key for all primitive types
+            default:
+                return empty_str;
+        }
+    }
+
+    /// return value of the iterator
+    typename IteratorType::reference value() const
+    {
+        return anchor.value();
+    }
+};
+
+/// proxy class for the items() function
+template<typename IteratorType> class iteration_proxy
+{
+  private:
+    /// the container to iterate
+    typename IteratorType::reference container;
+
+  public:
+    /// construct iteration proxy from a container
+    explicit iteration_proxy(typename IteratorType::reference cont) noexcept
+        : container(cont) {}
+
+    /// return iterator begin (needed for range-based for)
+    iteration_proxy_value<IteratorType> begin() noexcept
+    {
+        return iteration_proxy_value<IteratorType>(container.begin());
+    }
+
+    /// return iterator end (needed for range-based for)
+    iteration_proxy_value<IteratorType> end() noexcept
+    {
+        return iteration_proxy_value<IteratorType>(container.end());
+    }
+};
+// Structured Bindings Support
+// For further reference see https://blog.tartanllama.xyz/structured-bindings/
+// And see https://github.com/nlohmann/json/pull/1391
+template <std::size_t N, typename IteratorType, enable_if_t<N == 0, int> = 0>
+auto get(const nlohmann::detail::iteration_proxy_value<IteratorType>& i) -> decltype(i.key())
+{
+    return i.key();
+}
+// Structured Bindings Support
+// For further reference see https://blog.tartanllama.xyz/structured-bindings/
+// And see https://github.com/nlohmann/json/pull/1391
+template <std::size_t N, typename IteratorType, enable_if_t<N == 1, int> = 0>
+auto get(const nlohmann::detail::iteration_proxy_value<IteratorType>& i) -> decltype(i.value())
+{
+    return i.value();
+}
+}  // namespace detail
+}  // namespace nlohmann
+
+// The Addition to the STD Namespace is required to add
+// Structured Bindings Support to the iteration_proxy_value class
+// For further reference see https://blog.tartanllama.xyz/structured-bindings/
+// And see https://github.com/nlohmann/json/pull/1391
+namespace std
+{
+template <typename IteratorType>
+class tuple_size<::nlohmann::detail::iteration_proxy_value<IteratorType>>
+            : public std::integral_constant<std::size_t, 2> {};
+
+template <std::size_t N, typename IteratorType>
+class tuple_element<N, ::nlohmann::detail::iteration_proxy_value<IteratorType >>
+{
+  public:
+    using type = decltype(
+                     get<N>(std::declval <
+                            ::nlohmann::detail::iteration_proxy_value<IteratorType >> ()));
+};
+}
+
+namespace nlohmann
+{
+namespace detail
+{
+//////////////////
+// constructors //
+//////////////////
+
+template<value_t> struct external_constructor;
+
+template<>
+struct external_constructor<value_t::boolean>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept
+    {
+        j.m_type = value_t::boolean;
+        j.m_value = b;
+        j.assert_invariant();
+    }
+};
+
+template<>
+struct external_constructor<value_t::string>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s)
+    {
+        j.m_type = value_t::string;
+        j.m_value = s;
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s)
+    {
+        j.m_type = value_t::string;
+        j.m_value = std::move(s);
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType, typename CompatibleStringType,
+             enable_if_t<not std::is_same<CompatibleStringType, typename BasicJsonType::string_t>::value,
+                         int> = 0>
+    static void construct(BasicJsonType& j, const CompatibleStringType& str)
+    {
+        j.m_type = value_t::string;
+        j.m_value.string = j.template create<typename BasicJsonType::string_t>(str);
+        j.assert_invariant();
+    }
+};
+
+template<>
+struct external_constructor<value_t::number_float>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept
+    {
+        j.m_type = value_t::number_float;
+        j.m_value = val;
+        j.assert_invariant();
+    }
+};
+
+template<>
+struct external_constructor<value_t::number_unsigned>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept
+    {
+        j.m_type = value_t::number_unsigned;
+        j.m_value = val;
+        j.assert_invariant();
+    }
+};
+
+template<>
+struct external_constructor<value_t::number_integer>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept
+    {
+        j.m_type = value_t::number_integer;
+        j.m_value = val;
+        j.assert_invariant();
+    }
+};
+
+template<>
+struct external_constructor<value_t::array>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr)
+    {
+        j.m_type = value_t::array;
+        j.m_value = arr;
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
+    {
+        j.m_type = value_t::array;
+        j.m_value = std::move(arr);
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType, typename CompatibleArrayType,
+             enable_if_t<not std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value,
+                         int> = 0>
+    static void construct(BasicJsonType& j, const CompatibleArrayType& arr)
+    {
+        using std::begin;
+        using std::end;
+        j.m_type = value_t::array;
+        j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, const std::vector<bool>& arr)
+    {
+        j.m_type = value_t::array;
+        j.m_value = value_t::array;
+        j.m_value.array->reserve(arr.size());
+        for (const bool x : arr)
+        {
+            j.m_value.array->push_back(x);
+        }
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType, typename T,
+             enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
+    static void construct(BasicJsonType& j, const std::valarray<T>& arr)
+    {
+        j.m_type = value_t::array;
+        j.m_value = value_t::array;
+        j.m_value.array->resize(arr.size());
+        std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
+        j.assert_invariant();
+    }
+};
+
+template<>
+struct external_constructor<value_t::object>
+{
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj)
+    {
+        j.m_type = value_t::object;
+        j.m_value = obj;
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType>
+    static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
+    {
+        j.m_type = value_t::object;
+        j.m_value = std::move(obj);
+        j.assert_invariant();
+    }
+
+    template<typename BasicJsonType, typename CompatibleObjectType,
+             enable_if_t<not std::is_same<CompatibleObjectType, typename BasicJsonType::object_t>::value, int> = 0>
+    static void construct(BasicJsonType& j, const CompatibleObjectType& obj)
+    {
+        using std::begin;
+        using std::end;
+
+        j.m_type = value_t::object;
+        j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
+        j.assert_invariant();
+    }
+};
+
+/////////////
+// to_json //
+/////////////
+
+template<typename BasicJsonType, typename T,
+         enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value, int> = 0>
+void to_json(BasicJsonType& j, T b) noexcept
+{
+    external_constructor<value_t::boolean>::construct(j, b);
+}
+
+template<typename BasicJsonType, typename CompatibleString,
+         enable_if_t<std::is_constructible<typename BasicJsonType::string_t, CompatibleString>::value, int> = 0>
+void to_json(BasicJsonType& j, const CompatibleString& s)
+{
+    external_constructor<value_t::string>::construct(j, s);
+}
+
+template<typename BasicJsonType>
+void to_json(BasicJsonType& j, typename BasicJsonType::string_t&& s)
+{
+    external_constructor<value_t::string>::construct(j, std::move(s));
+}
+
+template<typename BasicJsonType, typename FloatType,
+         enable_if_t<std::is_floating_point<FloatType>::value, int> = 0>
+void to_json(BasicJsonType& j, FloatType val) noexcept
+{
+    external_constructor<value_t::number_float>::construct(j, static_cast<typename BasicJsonType::number_float_t>(val));
+}
+
+template<typename BasicJsonType, typename CompatibleNumberUnsignedType,
+         enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_unsigned_t, CompatibleNumberUnsignedType>::value, int> = 0>
+void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept
+{
+    external_constructor<value_t::number_unsigned>::construct(j, static_cast<typename BasicJsonType::number_unsigned_t>(val));
+}
+
+template<typename BasicJsonType, typename CompatibleNumberIntegerType,
+         enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_integer_t, CompatibleNumberIntegerType>::value, int> = 0>
+void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept
+{
+    external_constructor<value_t::number_integer>::construct(j, static_cast<typename BasicJsonType::number_integer_t>(val));
+}
+
+template<typename BasicJsonType, typename EnumType,
+         enable_if_t<std::is_enum<EnumType>::value, int> = 0>
+void to_json(BasicJsonType& j, EnumType e) noexcept
+{
+    using underlying_type = typename std::underlying_type<EnumType>::type;
+    external_constructor<value_t::number_integer>::construct(j, static_cast<underlying_type>(e));
+}
+
+template<typename BasicJsonType>
+void to_json(BasicJsonType& j, const std::vector<bool>& e)
+{
+    external_constructor<value_t::array>::construct(j, e);
+}
+
+template <typename BasicJsonType, typename CompatibleArrayType,
+          enable_if_t<is_compatible_array_type<BasicJsonType,
+                      CompatibleArrayType>::value and
+                      not is_compatible_object_type<
+                          BasicJsonType, CompatibleArrayType>::value and
+                      not is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value and
+                      not is_basic_json<CompatibleArrayType>::value,
+                      int> = 0>
+void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
+{
+    external_constructor<value_t::array>::construct(j, arr);
+}
+
+template<typename BasicJsonType, typename T,
+         enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
+void to_json(BasicJsonType& j, const std::valarray<T>& arr)
+{
+    external_constructor<value_t::array>::construct(j, std::move(arr));
+}
+
+template<typename BasicJsonType>
+void to_json(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
+{
+    external_constructor<value_t::array>::construct(j, std::move(arr));
+}
+
+template<typename BasicJsonType, typename CompatibleObjectType,
+         enable_if_t<is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value and not is_basic_json<CompatibleObjectType>::value, int> = 0>
+void to_json(BasicJsonType& j, const CompatibleObjectType& obj)
+{
+    external_constructor<value_t::object>::construct(j, obj);
+}
+
+template<typename BasicJsonType>
+void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
+{
+    external_constructor<value_t::object>::construct(j, std::move(obj));
+}
+
+template <
+    typename BasicJsonType, typename T, std::size_t N,
+    enable_if_t<not std::is_constructible<typename BasicJsonType::string_t,
+                const T(&)[N]>::value,
+                int> = 0 >
+void to_json(BasicJsonType& j, const T(&arr)[N])
+{
+    external_constructor<value_t::array>::construct(j, arr);
+}
+
+template<typename BasicJsonType, typename... Args>
+void to_json(BasicJsonType& j, const std::pair<Args...>& p)
+{
+    j = { p.first, p.second };
+}
+
+// for https://github.com/nlohmann/json/pull/1134
+template < typename BasicJsonType, typename T,
+           enable_if_t<std::is_same<T, iteration_proxy_value<typename BasicJsonType::iterator>>::value, int> = 0>
+void to_json(BasicJsonType& j, const T& b)
+{
+    j = { {b.key(), b.value()} };
+}
+
+template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
+void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<Idx...> /*unused*/)
+{
+    j = { std::get<Idx>(t)... };
+}
+
+template<typename BasicJsonType, typename... Args>
+void to_json(BasicJsonType& j, const std::tuple<Args...>& t)
+{
+    to_json_tuple_impl(j, t, index_sequence_for<Args...> {});
+}
+
+struct to_json_fn
+{
+    template<typename BasicJsonType, typename T>
+    auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
+    -> decltype(to_json(j, std::forward<T>(val)), void())
+    {
+        return to_json(j, std::forward<T>(val));
+    }
+};
+}  // namespace detail
+
+/// namespace to hold default `to_json` function
+namespace
+{
+constexpr const auto& to_json = detail::static_const<detail::to_json_fn>::value;
+} // namespace
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/input/input_adapters.hpp>
+
+
+#include <cassert> // assert
+#include <cstddef> // size_t
+#include <cstring> // strlen
+#include <istream> // istream
+#include <iterator> // begin, end, iterator_traits, random_access_iterator_tag, distance, next
+#include <memory> // shared_ptr, make_shared, addressof
+#include <numeric> // accumulate
+#include <string> // string, char_traits
+#include <type_traits> // enable_if, is_base_of, is_pointer, is_integral, remove_pointer
+#include <utility> // pair, declval
+#include <cstdio> //FILE *
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+/// the supported input formats
+enum class input_format_t { json, cbor, msgpack, ubjson, bson };
+
+////////////////////
+// input adapters //
+////////////////////
+
+/*!
+@brief abstract input adapter interface
+
+Produces a stream of std::char_traits<char>::int_type characters from a
+std::istream, a buffer, or some other input type. Accepts the return of
+exactly one non-EOF character for future input. The int_type characters
+returned consist of all valid char values as positive values (typically
+unsigned char), plus an EOF value outside that range, specified by the value
+of the function std::char_traits<char>::eof(). This value is typically -1, but
+could be any arbitrary value which is not a valid char value.
+*/
+struct input_adapter_protocol
+{
+    /// get a character [0,255] or std::char_traits<char>::eof().
+    virtual std::char_traits<char>::int_type get_character() = 0;
+    virtual ~input_adapter_protocol() = default;
+};
+
+/// a type to simplify interfaces
+using input_adapter_t = std::shared_ptr<input_adapter_protocol>;
+
+/*!
+Input adapter for stdio file access. This adapter read only 1 byte and do not use any
+ buffer. This adapter is a very low level adapter.
+*/
+class file_input_adapter : public input_adapter_protocol
+{
+  public:
+    explicit file_input_adapter(std::FILE* f)  noexcept
+        : m_file(f)
+    {}
+
+    std::char_traits<char>::int_type get_character() noexcept override
+    {
+        return std::fgetc(m_file);
+    }
+  private:
+    /// the file pointer to read from
+    std::FILE* m_file;
+};
+
+
+/*!
+Input adapter for a (caching) istream. Ignores a UFT Byte Order Mark at
+beginning of input. Does not support changing the underlying std::streambuf
+in mid-input. Maintains underlying std::istream and std::streambuf to support
+subsequent use of standard std::istream operations to process any input
+characters following those used in parsing the JSON input.  Clears the
+std::istream flags; any input errors (e.g., EOF) will be detected by the first
+subsequent call for input from the std::istream.
+*/
+class input_stream_adapter : public input_adapter_protocol
+{
+  public:
+    ~input_stream_adapter() override
+    {
+        // clear stream flags; we use underlying streambuf I/O, do not
+        // maintain ifstream flags, except eof
+        is.clear(is.rdstate() & std::ios::eofbit);
+    }
+
+    explicit input_stream_adapter(std::istream& i)
+        : is(i), sb(*i.rdbuf())
+    {}
+
+    // delete because of pointer members
+    input_stream_adapter(const input_stream_adapter&) = delete;
+    input_stream_adapter& operator=(input_stream_adapter&) = delete;
+    input_stream_adapter(input_stream_adapter&&) = delete;
+    input_stream_adapter& operator=(input_stream_adapter&&) = delete;
+
+    // std::istream/std::streambuf use std::char_traits<char>::to_int_type, to
+    // ensure that std::char_traits<char>::eof() and the character 0xFF do not
+    // end up as the same value, eg. 0xFFFFFFFF.
+    std::char_traits<char>::int_type get_character() override
+    {
+        auto res = sb.sbumpc();
+        // set eof manually, as we don't use the istream interface.
+        if (res == EOF)
+        {
+            is.clear(is.rdstate() | std::ios::eofbit);
+        }
+        return res;
+    }
+
+  private:
+    /// the associated input stream
+    std::istream& is;
+    std::streambuf& sb;
+};
+
+/// input adapter for buffer input
+class input_buffer_adapter : public input_adapter_protocol
+{
+  public:
+    input_buffer_adapter(const char* b, const std::size_t l) noexcept
+        : cursor(b), limit(b + l)
+    {}
+
+    // delete because of pointer members
+    input_buffer_adapter(const input_buffer_adapter&) = delete;
+    input_buffer_adapter& operator=(input_buffer_adapter&) = delete;
+    input_buffer_adapter(input_buffer_adapter&&) = delete;
+    input_buffer_adapter& operator=(input_buffer_adapter&&) = delete;
+    ~input_buffer_adapter() override = default;
+
+    std::char_traits<char>::int_type get_character() noexcept override
+    {
+        if (JSON_LIKELY(cursor < limit))
+        {
+            return std::char_traits<char>::to_int_type(*(cursor++));
+        }
+
+        return std::char_traits<char>::eof();
+    }
+
+  private:
+    /// pointer to the current character
+    const char* cursor;
+    /// pointer past the last character
+    const char* const limit;
+};
+
+template<typename WideStringType, size_t T>
+struct wide_string_input_helper
+{
+    // UTF-32
+    static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled)
+    {
+        utf8_bytes_index = 0;
+
+        if (current_wchar == str.size())
+        {
+            utf8_bytes[0] = std::char_traits<char>::eof();
+            utf8_bytes_filled = 1;
+        }
+        else
+        {
+            // get the current character
+            const auto wc = static_cast<int>(str[current_wchar++]);
+
+            // UTF-32 to UTF-8 encoding
+            if (wc < 0x80)
+            {
+                utf8_bytes[0] = wc;
+                utf8_bytes_filled = 1;
+            }
+            else if (wc <= 0x7FF)
+            {
+                utf8_bytes[0] = 0xC0 | ((wc >> 6) & 0x1F);
+                utf8_bytes[1] = 0x80 | (wc & 0x3F);
+                utf8_bytes_filled = 2;
+            }
+            else if (wc <= 0xFFFF)
+            {
+                utf8_bytes[0] = 0xE0 | ((wc >> 12) & 0x0F);
+                utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F);
+                utf8_bytes[2] = 0x80 | (wc & 0x3F);
+                utf8_bytes_filled = 3;
+            }
+            else if (wc <= 0x10FFFF)
+            {
+                utf8_bytes[0] = 0xF0 | ((wc >> 18) & 0x07);
+                utf8_bytes[1] = 0x80 | ((wc >> 12) & 0x3F);
+                utf8_bytes[2] = 0x80 | ((wc >> 6) & 0x3F);
+                utf8_bytes[3] = 0x80 | (wc & 0x3F);
+                utf8_bytes_filled = 4;
+            }
+            else
+            {
+                // unknown character
+                utf8_bytes[0] = wc;
+                utf8_bytes_filled = 1;
+            }
+        }
+    }
+};
+
+template<typename WideStringType>
+struct wide_string_input_helper<WideStringType, 2>
+{
+    // UTF-16
+    static void fill_buffer(const WideStringType& str, size_t& current_wchar, std::array<std::char_traits<char>::int_type, 4>& utf8_bytes, size_t& utf8_bytes_index, size_t& utf8_bytes_filled)
+    {
+        utf8_bytes_index = 0;
+
+        if (current_wchar == str.size())
+        {
+            utf8_bytes[0] = std::char_traits<char>::eof();
+            utf8_bytes_filled = 1;
+        }
+        else
+        {
+            // get the current character
+            const auto wc = static_cast<int>(str[current_wchar++]);
+
+            // UTF-16 to UTF-8 encoding
+            if (wc < 0x80)
+            {
+                utf8_bytes[0] = wc;
+                utf8_bytes_filled = 1;
+            }
+            else if (wc <= 0x7FF)
+            {
+                utf8_bytes[0] = 0xC0 | ((wc >> 6));
+                utf8_bytes[1] = 0x80 | (wc & 0x3F);
+                utf8_bytes_filled = 2;
+            }
+            else if (0xD800 > wc or wc >= 0xE000)
+            {
+                utf8_bytes[0] = 0xE0 | ((wc >> 12));
+                utf8_bytes[1] = 0x80 | ((wc >> 6) & 0x3F);
+                utf8_bytes[2] = 0x80 | (wc & 0x3F);
+                utf8_bytes_filled = 3;
+            }
+            else
+            {
+                if (current_wchar < str.size())
+                {
+                    const auto wc2 = static_cast<int>(str[current_wchar++]);
+                    const int charcode = 0x10000 + (((wc & 0x3FF) << 10) | (wc2 & 0x3FF));
+                    utf8_bytes[0] = 0xf0 | (charcode >> 18);
+                    utf8_bytes[1] = 0x80 | ((charcode >> 12) & 0x3F);
+                    utf8_bytes[2] = 0x80 | ((charcode >> 6) & 0x3F);
+                    utf8_bytes[3] = 0x80 | (charcode & 0x3F);
+                    utf8_bytes_filled = 4;
+                }
+                else
+                {
+                    // unknown character
+                    ++current_wchar;
+                    utf8_bytes[0] = wc;
+                    utf8_bytes_filled = 1;
+                }
+            }
+        }
+    }
+};
+
+template<typename WideStringType>
+class wide_string_input_adapter : public input_adapter_protocol
+{
+  public:
+    explicit wide_string_input_adapter(const WideStringType& w)  noexcept
+        : str(w)
+    {}
+
+    std::char_traits<char>::int_type get_character() noexcept override
+    {
+        // check if buffer needs to be filled
+        if (utf8_bytes_index == utf8_bytes_filled)
+        {
+            fill_buffer<sizeof(typename WideStringType::value_type)>();
+
+            assert(utf8_bytes_filled > 0);
+            assert(utf8_bytes_index == 0);
+        }
+
+        // use buffer
+        assert(utf8_bytes_filled > 0);
+        assert(utf8_bytes_index < utf8_bytes_filled);
+        return utf8_bytes[utf8_bytes_index++];
+    }
+
+  private:
+    template<size_t T>
+    void fill_buffer()
+    {
+        wide_string_input_helper<WideStringType, T>::fill_buffer(str, current_wchar, utf8_bytes, utf8_bytes_index, utf8_bytes_filled);
+    }
+
+    /// the wstring to process
+    const WideStringType& str;
+
+    /// index of the current wchar in str
+    std::size_t current_wchar = 0;
+
+    /// a buffer for UTF-8 bytes
+    std::array<std::char_traits<char>::int_type, 4> utf8_bytes = {{0, 0, 0, 0}};
+
+    /// index to the utf8_codes array for the next valid byte
+    std::size_t utf8_bytes_index = 0;
+    /// number of valid bytes in the utf8_codes array
+    std::size_t utf8_bytes_filled = 0;
+};
+
+class input_adapter
+{
+  public:
+    // native support
+    input_adapter(std::FILE* file)
+        : ia(std::make_shared<file_input_adapter>(file)) {}
+    /// input adapter for input stream
+    input_adapter(std::istream& i)
+        : ia(std::make_shared<input_stream_adapter>(i)) {}
+
+    /// input adapter for input stream
+    input_adapter(std::istream&& i)
+        : ia(std::make_shared<input_stream_adapter>(i)) {}
+
+    input_adapter(const std::wstring& ws)
+        : ia(std::make_shared<wide_string_input_adapter<std::wstring>>(ws)) {}
+
+    input_adapter(const std::u16string& ws)
+        : ia(std::make_shared<wide_string_input_adapter<std::u16string>>(ws)) {}
+
+    input_adapter(const std::u32string& ws)
+        : ia(std::make_shared<wide_string_input_adapter<std::u32string>>(ws)) {}
+
+    /// input adapter for buffer
+    template<typename CharT,
+             typename std::enable_if<
+                 std::is_pointer<CharT>::value and
+                 std::is_integral<typename std::remove_pointer<CharT>::type>::value and
+                 sizeof(typename std::remove_pointer<CharT>::type) == 1,
+                 int>::type = 0>
+    input_adapter(CharT b, std::size_t l)
+        : ia(std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(b), l)) {}
+
+    // derived support
+
+    /// input adapter for string literal
+    template<typename CharT,
+             typename std::enable_if<
+                 std::is_pointer<CharT>::value and
+                 std::is_integral<typename std::remove_pointer<CharT>::type>::value and
+                 sizeof(typename std::remove_pointer<CharT>::type) == 1,
+                 int>::type = 0>
+    input_adapter(CharT b)
+        : input_adapter(reinterpret_cast<const char*>(b),
+                        std::strlen(reinterpret_cast<const char*>(b))) {}
+
+    /// input adapter for iterator range with contiguous storage
+    template<class IteratorType,
+             typename std::enable_if<
+                 std::is_same<typename iterator_traits<IteratorType>::iterator_category, std::random_access_iterator_tag>::value,
+                 int>::type = 0>
+    input_adapter(IteratorType first, IteratorType last)
+    {
+#ifndef NDEBUG
+        // assertion to check that the iterator range is indeed contiguous,
+        // see http://stackoverflow.com/a/35008842/266378 for more discussion
+        const auto is_contiguous = std::accumulate(
+                                       first, last, std::pair<bool, int>(true, 0),
+                                       [&first](std::pair<bool, int> res, decltype(*first) val)
+        {
+            res.first &= (val == *(std::next(std::addressof(*first), res.second++)));
+            return res;
+        }).first;
+        assert(is_contiguous);
+#endif
+
+        // assertion to check that each element is 1 byte long
+        static_assert(
+            sizeof(typename iterator_traits<IteratorType>::value_type) == 1,
+            "each element in the iterator range must have the size of 1 byte");
+
+        const auto len = static_cast<size_t>(std::distance(first, last));
+        if (JSON_LIKELY(len > 0))
+        {
+            // there is at least one element: use the address of first
+            ia = std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(&(*first)), len);
+        }
+        else
+        {
+            // the address of first cannot be used: use nullptr
+            ia = std::make_shared<input_buffer_adapter>(nullptr, len);
+        }
+    }
+
+    /// input adapter for array
+    template<class T, std::size_t N>
+    input_adapter(T (&array)[N])
+        : input_adapter(std::begin(array), std::end(array)) {}
+
+    /// input adapter for contiguous container
+    template<class ContiguousContainer, typename
+             std::enable_if<not std::is_pointer<ContiguousContainer>::value and
+                            std::is_base_of<std::random_access_iterator_tag, typename iterator_traits<decltype(std::begin(std::declval<ContiguousContainer const>()))>::iterator_category>::value,
+                            int>::type = 0>
+    input_adapter(const ContiguousContainer& c)
+        : input_adapter(std::begin(c), std::end(c)) {}
+
+    operator input_adapter_t()
+    {
+        return ia;
+    }
+
+  private:
+    /// the actual adapter
+    input_adapter_t ia = nullptr;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/input/lexer.hpp>
+
+
+#include <clocale> // localeconv
+#include <cstddef> // size_t
+#include <cstdlib> // strtof, strtod, strtold, strtoll, strtoull
+#include <cstdio> // snprintf
+#include <initializer_list> // initializer_list
+#include <string> // char_traits, string
+#include <vector> // vector
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/input/input_adapters.hpp>
+
+// #include <nlohmann/detail/input/position_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+///////////
+// lexer //
+///////////
+
+/*!
+@brief lexical analysis
+
+This class organizes the lexical analysis during JSON deserialization.
+*/
+template<typename BasicJsonType>
+class lexer
+{
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+
+  public:
+    /// token types for the parser
+    enum class token_type
+    {
+        uninitialized,    ///< indicating the scanner is uninitialized
+        literal_true,     ///< the `true` literal
+        literal_false,    ///< the `false` literal
+        literal_null,     ///< the `null` literal
+        value_string,     ///< a string -- use get_string() for actual value
+        value_unsigned,   ///< an unsigned integer -- use get_number_unsigned() for actual value
+        value_integer,    ///< a signed integer -- use get_number_integer() for actual value
+        value_float,      ///< an floating point number -- use get_number_float() for actual value
+        begin_array,      ///< the character for array begin `[`
+        begin_object,     ///< the character for object begin `{`
+        end_array,        ///< the character for array end `]`
+        end_object,       ///< the character for object end `}`
+        name_separator,   ///< the name separator `:`
+        value_separator,  ///< the value separator `,`
+        parse_error,      ///< indicating a parse error
+        end_of_input,     ///< indicating the end of the input buffer
+        literal_or_value  ///< a literal or the begin of a value (only for diagnostics)
+    };
+
+    /// return name of values of type token_type (only used for errors)
+    static const char* token_type_name(const token_type t) noexcept
+    {
+        switch (t)
+        {
+            case token_type::uninitialized:
+                return "<uninitialized>";
+            case token_type::literal_true:
+                return "true literal";
+            case token_type::literal_false:
+                return "false literal";
+            case token_type::literal_null:
+                return "null literal";
+            case token_type::value_string:
+                return "string literal";
+            case lexer::token_type::value_unsigned:
+            case lexer::token_type::value_integer:
+            case lexer::token_type::value_float:
+                return "number literal";
+            case token_type::begin_array:
+                return "'['";
+            case token_type::begin_object:
+                return "'{'";
+            case token_type::end_array:
+                return "']'";
+            case token_type::end_object:
+                return "'}'";
+            case token_type::name_separator:
+                return "':'";
+            case token_type::value_separator:
+                return "','";
+            case token_type::parse_error:
+                return "<parse error>";
+            case token_type::end_of_input:
+                return "end of input";
+            case token_type::literal_or_value:
+                return "'[', '{', or a literal";
+            // LCOV_EXCL_START
+            default: // catch non-enum values
+                return "unknown token";
+                // LCOV_EXCL_STOP
+        }
+    }
+
+    explicit lexer(detail::input_adapter_t&& adapter)
+        : ia(std::move(adapter)), decimal_point_char(get_decimal_point()) {}
+
+    // delete because of pointer members
+    lexer(const lexer&) = delete;
+    lexer(lexer&&) = delete;
+    lexer& operator=(lexer&) = delete;
+    lexer& operator=(lexer&&) = delete;
+    ~lexer() = default;
+
+  private:
+    /////////////////////
+    // locales
+    /////////////////////
+
+    /// return the locale-dependent decimal point
+    static char get_decimal_point() noexcept
+    {
+        const auto loc = localeconv();
+        assert(loc != nullptr);
+        return (loc->decimal_point == nullptr) ? '.' : *(loc->decimal_point);
+    }
+
+    /////////////////////
+    // scan functions
+    /////////////////////
+
+    /*!
+    @brief get codepoint from 4 hex characters following `\u`
+
+    For input "\u c1 c2 c3 c4" the codepoint is:
+      (c1 * 0x1000) + (c2 * 0x0100) + (c3 * 0x0010) + c4
+    = (c1 << 12) + (c2 << 8) + (c3 << 4) + (c4 << 0)
+
+    Furthermore, the possible characters '0'..'9', 'A'..'F', and 'a'..'f'
+    must be converted to the integers 0x0..0x9, 0xA..0xF, 0xA..0xF, resp. The
+    conversion is done by subtracting the offset (0x30, 0x37, and 0x57)
+    between the ASCII value of the character and the desired integer value.
+
+    @return codepoint (0x0000..0xFFFF) or -1 in case of an error (e.g. EOF or
+            non-hex character)
+    */
+    int get_codepoint()
+    {
+        // this function only makes sense after reading `\u`
+        assert(current == 'u');
+        int codepoint = 0;
+
+        const auto factors = { 12, 8, 4, 0 };
+        for (const auto factor : factors)
+        {
+            get();
+
+            if (current >= '0' and current <= '9')
+            {
+                codepoint += ((current - 0x30) << factor);
+            }
+            else if (current >= 'A' and current <= 'F')
+            {
+                codepoint += ((current - 0x37) << factor);
+            }
+            else if (current >= 'a' and current <= 'f')
+            {
+                codepoint += ((current - 0x57) << factor);
+            }
+            else
+            {
+                return -1;
+            }
+        }
+
+        assert(0x0000 <= codepoint and codepoint <= 0xFFFF);
+        return codepoint;
+    }
+
+    /*!
+    @brief check if the next byte(s) are inside a given range
+
+    Adds the current byte and, for each passed range, reads a new byte and
+    checks if it is inside the range. If a violation was detected, set up an
+    error message and return false. Otherwise, return true.
+
+    @param[in] ranges  list of integers; interpreted as list of pairs of
+                       inclusive lower and upper bound, respectively
+
+    @pre The passed list @a ranges must have 2, 4, or 6 elements; that is,
+         1, 2, or 3 pairs. This precondition is enforced by an assertion.
+
+    @return true if and only if no range violation was detected
+    */
+    bool next_byte_in_range(std::initializer_list<int> ranges)
+    {
+        assert(ranges.size() == 2 or ranges.size() == 4 or ranges.size() == 6);
+        add(current);
+
+        for (auto range = ranges.begin(); range != ranges.end(); ++range)
+        {
+            get();
+            if (JSON_LIKELY(*range <= current and current <= *(++range)))
+            {
+                add(current);
+            }
+            else
+            {
+                error_message = "invalid string: ill-formed UTF-8 byte";
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /*!
+    @brief scan a string literal
+
+    This function scans a string according to Sect. 7 of RFC 7159. While
+    scanning, bytes are escaped and copied into buffer token_buffer. Then the
+    function returns successfully, token_buffer is *not* null-terminated (as it
+    may contain \0 bytes), and token_buffer.size() is the number of bytes in the
+    string.
+
+    @return token_type::value_string if string could be successfully scanned,
+            token_type::parse_error otherwise
+
+    @note In case of errors, variable error_message contains a textual
+          description.
+    */
+    token_type scan_string()
+    {
+        // reset token_buffer (ignore opening quote)
+        reset();
+
+        // we entered the function by reading an open quote
+        assert(current == '\"');
+
+        while (true)
+        {
+            // get next character
+            switch (get())
+            {
+                // end of file while parsing string
+                case std::char_traits<char>::eof():
+                {
+                    error_message = "invalid string: missing closing quote";
+                    return token_type::parse_error;
+                }
+
+                // closing quote
+                case '\"':
+                {
+                    return token_type::value_string;
+                }
+
+                // escapes
+                case '\\':
+                {
+                    switch (get())
+                    {
+                        // quotation mark
+                        case '\"':
+                            add('\"');
+                            break;
+                        // reverse solidus
+                        case '\\':
+                            add('\\');
+                            break;
+                        // solidus
+                        case '/':
+                            add('/');
+                            break;
+                        // backspace
+                        case 'b':
+                            add('\b');
+                            break;
+                        // form feed
+                        case 'f':
+                            add('\f');
+                            break;
+                        // line feed
+                        case 'n':
+                            add('\n');
+                            break;
+                        // carriage return
+                        case 'r':
+                            add('\r');
+                            break;
+                        // tab
+                        case 't':
+                            add('\t');
+                            break;
+
+                        // unicode escapes
+                        case 'u':
+                        {
+                            const int codepoint1 = get_codepoint();
+                            int codepoint = codepoint1; // start with codepoint1
+
+                            if (JSON_UNLIKELY(codepoint1 == -1))
+                            {
+                                error_message = "invalid string: '\\u' must be followed by 4 hex digits";
+                                return token_type::parse_error;
+                            }
+
+                            // check if code point is a high surrogate
+                            if (0xD800 <= codepoint1 and codepoint1 <= 0xDBFF)
+                            {
+                                // expect next \uxxxx entry
+                                if (JSON_LIKELY(get() == '\\' and get() == 'u'))
+                                {
+                                    const int codepoint2 = get_codepoint();
+
+                                    if (JSON_UNLIKELY(codepoint2 == -1))
+                                    {
+                                        error_message = "invalid string: '\\u' must be followed by 4 hex digits";
+                                        return token_type::parse_error;
+                                    }
+
+                                    // check if codepoint2 is a low surrogate
+                                    if (JSON_LIKELY(0xDC00 <= codepoint2 and codepoint2 <= 0xDFFF))
+                                    {
+                                        // overwrite codepoint
+                                        codepoint =
+                                            // high surrogate occupies the most significant 22 bits
+                                            (codepoint1 << 10)
+                                            // low surrogate occupies the least significant 15 bits
+                                            + codepoint2
+                                            // there is still the 0xD800, 0xDC00 and 0x10000 noise
+                                            // in the result so we have to subtract with:
+                                            // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00
+                                            - 0x35FDC00;
+                                    }
+                                    else
+                                    {
+                                        error_message = "invalid string: surrogate U+DC00..U+DFFF must be followed by U+DC00..U+DFFF";
+                                        return token_type::parse_error;
+                                    }
+                                }
+                                else
+                                {
+                                    error_message = "invalid string: surrogate U+DC00..U+DFFF must be followed by U+DC00..U+DFFF";
+                                    return token_type::parse_error;
+                                }
+                            }
+                            else
+                            {
+                                if (JSON_UNLIKELY(0xDC00 <= codepoint1 and codepoint1 <= 0xDFFF))
+                                {
+                                    error_message = "invalid string: surrogate U+DC00..U+DFFF must follow U+D800..U+DBFF";
+                                    return token_type::parse_error;
+                                }
+                            }
+
+                            // result of the above calculation yields a proper codepoint
+                            assert(0x00 <= codepoint and codepoint <= 0x10FFFF);
+
+                            // translate codepoint into bytes
+                            if (codepoint < 0x80)
+                            {
+                                // 1-byte characters: 0xxxxxxx (ASCII)
+                                add(codepoint);
+                            }
+                            else if (codepoint <= 0x7FF)
+                            {
+                                // 2-byte characters: 110xxxxx 10xxxxxx
+                                add(0xC0 | (codepoint >> 6));
+                                add(0x80 | (codepoint & 0x3F));
+                            }
+                            else if (codepoint <= 0xFFFF)
+                            {
+                                // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx
+                                add(0xE0 | (codepoint >> 12));
+                                add(0x80 | ((codepoint >> 6) & 0x3F));
+                                add(0x80 | (codepoint & 0x3F));
+                            }
+                            else
+                            {
+                                // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+                                add(0xF0 | (codepoint >> 18));
+                                add(0x80 | ((codepoint >> 12) & 0x3F));
+                                add(0x80 | ((codepoint >> 6) & 0x3F));
+                                add(0x80 | (codepoint & 0x3F));
+                            }
+
+                            break;
+                        }
+
+                        // other characters after escape
+                        default:
+                            error_message = "invalid string: forbidden character after backslash";
+                            return token_type::parse_error;
+                    }
+
+                    break;
+                }
+
+                // invalid control characters
+                case 0x00:
+                {
+                    error_message = "invalid string: control character U+0000 (NUL) must be escaped to \\u0000";
+                    return token_type::parse_error;
+                }
+
+                case 0x01:
+                {
+                    error_message = "invalid string: control character U+0001 (SOH) must be escaped to \\u0001";
+                    return token_type::parse_error;
+                }
+
+                case 0x02:
+                {
+                    error_message = "invalid string: control character U+0002 (STX) must be escaped to \\u0002";
+                    return token_type::parse_error;
+                }
+
+                case 0x03:
+                {
+                    error_message = "invalid string: control character U+0003 (ETX) must be escaped to \\u0003";
+                    return token_type::parse_error;
+                }
+
+                case 0x04:
+                {
+                    error_message = "invalid string: control character U+0004 (EOT) must be escaped to \\u0004";
+                    return token_type::parse_error;
+                }
+
+                case 0x05:
+                {
+                    error_message = "invalid string: control character U+0005 (ENQ) must be escaped to \\u0005";
+                    return token_type::parse_error;
+                }
+
+                case 0x06:
+                {
+                    error_message = "invalid string: control character U+0006 (ACK) must be escaped to \\u0006";
+                    return token_type::parse_error;
+                }
+
+                case 0x07:
+                {
+                    error_message = "invalid string: control character U+0007 (BEL) must be escaped to \\u0007";
+                    return token_type::parse_error;
+                }
+
+                case 0x08:
+                {
+                    error_message = "invalid string: control character U+0008 (BS) must be escaped to \\u0008 or \\b";
+                    return token_type::parse_error;
+                }
+
+                case 0x09:
+                {
+                    error_message = "invalid string: control character U+0009 (HT) must be escaped to \\u0009 or \\t";
+                    return token_type::parse_error;
+                }
+
+                case 0x0A:
+                {
+                    error_message = "invalid string: control character U+000A (LF) must be escaped to \\u000A or \\n";
+                    return token_type::parse_error;
+                }
+
+                case 0x0B:
+                {
+                    error_message = "invalid string: control character U+000B (VT) must be escaped to \\u000B";
+                    return token_type::parse_error;
+                }
+
+                case 0x0C:
+                {
+                    error_message = "invalid string: control character U+000C (FF) must be escaped to \\u000C or \\f";
+                    return token_type::parse_error;
+                }
+
+                case 0x0D:
+                {
+                    error_message = "invalid string: control character U+000D (CR) must be escaped to \\u000D or \\r";
+                    return token_type::parse_error;
+                }
+
+                case 0x0E:
+                {
+                    error_message = "invalid string: control character U+000E (SO) must be escaped to \\u000E";
+                    return token_type::parse_error;
+                }
+
+                case 0x0F:
+                {
+                    error_message = "invalid string: control character U+000F (SI) must be escaped to \\u000F";
+                    return token_type::parse_error;
+                }
+
+                case 0x10:
+                {
+                    error_message = "invalid string: control character U+0010 (DLE) must be escaped to \\u0010";
+                    return token_type::parse_error;
+                }
+
+                case 0x11:
+                {
+                    error_message = "invalid string: control character U+0011 (DC1) must be escaped to \\u0011";
+                    return token_type::parse_error;
+                }
+
+                case 0x12:
+                {
+                    error_message = "invalid string: control character U+0012 (DC2) must be escaped to \\u0012";
+                    return token_type::parse_error;
+                }
+
+                case 0x13:
+                {
+                    error_message = "invalid string: control character U+0013 (DC3) must be escaped to \\u0013";
+                    return token_type::parse_error;
+                }
+
+                case 0x14:
+                {
+                    error_message = "invalid string: control character U+0014 (DC4) must be escaped to \\u0014";
+                    return token_type::parse_error;
+                }
+
+                case 0x15:
+                {
+                    error_message = "invalid string: control character U+0015 (NAK) must be escaped to \\u0015";
+                    return token_type::parse_error;
+                }
+
+                case 0x16:
+                {
+                    error_message = "invalid string: control character U+0016 (SYN) must be escaped to \\u0016";
+                    return token_type::parse_error;
+                }
+
+                case 0x17:
+                {
+                    error_message = "invalid string: control character U+0017 (ETB) must be escaped to \\u0017";
+                    return token_type::parse_error;
+                }
+
+                case 0x18:
+                {
+                    error_message = "invalid string: control character U+0018 (CAN) must be escaped to \\u0018";
+                    return token_type::parse_error;
+                }
+
+                case 0x19:
+                {
+                    error_message = "invalid string: control character U+0019 (EM) must be escaped to \\u0019";
+                    return token_type::parse_error;
+                }
+
+                case 0x1A:
+                {
+                    error_message = "invalid string: control character U+001A (SUB) must be escaped to \\u001A";
+                    return token_type::parse_error;
+                }
+
+                case 0x1B:
+                {
+                    error_message = "invalid string: control character U+001B (ESC) must be escaped to \\u001B";
+                    return token_type::parse_error;
+                }
+
+                case 0x1C:
+                {
+                    error_message = "invalid string: control character U+001C (FS) must be escaped to \\u001C";
+                    return token_type::parse_error;
+                }
+
+                case 0x1D:
+                {
+                    error_message = "invalid string: control character U+001D (GS) must be escaped to \\u001D";
+                    return token_type::parse_error;
+                }
+
+                case 0x1E:
+                {
+                    error_message = "invalid string: control character U+001E (RS) must be escaped to \\u001E";
+                    return token_type::parse_error;
+                }
+
+                case 0x1F:
+                {
+                    error_message = "invalid string: control character U+001F (US) must be escaped to \\u001F";
+                    return token_type::parse_error;
+                }
+
+                // U+0020..U+007F (except U+0022 (quote) and U+005C (backspace))
+                case 0x20:
+                case 0x21:
+                case 0x23:
+                case 0x24:
+                case 0x25:
+                case 0x26:
+                case 0x27:
+                case 0x28:
+                case 0x29:
+                case 0x2A:
+                case 0x2B:
+                case 0x2C:
+                case 0x2D:
+                case 0x2E:
+                case 0x2F:
+                case 0x30:
+                case 0x31:
+                case 0x32:
+                case 0x33:
+                case 0x34:
+                case 0x35:
+                case 0x36:
+                case 0x37:
+                case 0x38:
+                case 0x39:
+                case 0x3A:
+                case 0x3B:
+                case 0x3C:
+                case 0x3D:
+                case 0x3E:
+                case 0x3F:
+                case 0x40:
+                case 0x41:
+                case 0x42:
+                case 0x43:
+                case 0x44:
+                case 0x45:
+                case 0x46:
+                case 0x47:
+                case 0x48:
+                case 0x49:
+                case 0x4A:
+                case 0x4B:
+                case 0x4C:
+                case 0x4D:
+                case 0x4E:
+                case 0x4F:
+                case 0x50:
+                case 0x51:
+                case 0x52:
+                case 0x53:
+                case 0x54:
+                case 0x55:
+                case 0x56:
+                case 0x57:
+                case 0x58:
+                case 0x59:
+                case 0x5A:
+                case 0x5B:
+                case 0x5D:
+                case 0x5E:
+                case 0x5F:
+                case 0x60:
+                case 0x61:
+                case 0x62:
+                case 0x63:
+                case 0x64:
+                case 0x65:
+                case 0x66:
+                case 0x67:
+                case 0x68:
+                case 0x69:
+                case 0x6A:
+                case 0x6B:
+                case 0x6C:
+                case 0x6D:
+                case 0x6E:
+                case 0x6F:
+                case 0x70:
+                case 0x71:
+                case 0x72:
+                case 0x73:
+                case 0x74:
+                case 0x75:
+                case 0x76:
+                case 0x77:
+                case 0x78:
+                case 0x79:
+                case 0x7A:
+                case 0x7B:
+                case 0x7C:
+                case 0x7D:
+                case 0x7E:
+                case 0x7F:
+                {
+                    add(current);
+                    break;
+                }
+
+                // U+0080..U+07FF: bytes C2..DF 80..BF
+                case 0xC2:
+                case 0xC3:
+                case 0xC4:
+                case 0xC5:
+                case 0xC6:
+                case 0xC7:
+                case 0xC8:
+                case 0xC9:
+                case 0xCA:
+                case 0xCB:
+                case 0xCC:
+                case 0xCD:
+                case 0xCE:
+                case 0xCF:
+                case 0xD0:
+                case 0xD1:
+                case 0xD2:
+                case 0xD3:
+                case 0xD4:
+                case 0xD5:
+                case 0xD6:
+                case 0xD7:
+                case 0xD8:
+                case 0xD9:
+                case 0xDA:
+                case 0xDB:
+                case 0xDC:
+                case 0xDD:
+                case 0xDE:
+                case 0xDF:
+                {
+                    if (JSON_UNLIKELY(not next_byte_in_range({0x80, 0xBF})))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // U+0800..U+0FFF: bytes E0 A0..BF 80..BF
+                case 0xE0:
+                {
+                    if (JSON_UNLIKELY(not (next_byte_in_range({0xA0, 0xBF, 0x80, 0xBF}))))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // U+1000..U+CFFF: bytes E1..EC 80..BF 80..BF
+                // U+E000..U+FFFF: bytes EE..EF 80..BF 80..BF
+                case 0xE1:
+                case 0xE2:
+                case 0xE3:
+                case 0xE4:
+                case 0xE5:
+                case 0xE6:
+                case 0xE7:
+                case 0xE8:
+                case 0xE9:
+                case 0xEA:
+                case 0xEB:
+                case 0xEC:
+                case 0xEE:
+                case 0xEF:
+                {
+                    if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0xBF, 0x80, 0xBF}))))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // U+D000..U+D7FF: bytes ED 80..9F 80..BF
+                case 0xED:
+                {
+                    if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0x9F, 0x80, 0xBF}))))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // U+10000..U+3FFFF F0 90..BF 80..BF 80..BF
+                case 0xF0:
+                {
+                    if (JSON_UNLIKELY(not (next_byte_in_range({0x90, 0xBF, 0x80, 0xBF, 0x80, 0xBF}))))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
+                case 0xF1:
+                case 0xF2:
+                case 0xF3:
+                {
+                    if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0xBF, 0x80, 0xBF, 0x80, 0xBF}))))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // U+100000..U+10FFFF F4 80..8F 80..BF 80..BF
+                case 0xF4:
+                {
+                    if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0x8F, 0x80, 0xBF, 0x80, 0xBF}))))
+                    {
+                        return token_type::parse_error;
+                    }
+                    break;
+                }
+
+                // remaining bytes (80..C1 and F5..FF) are ill-formed
+                default:
+                {
+                    error_message = "invalid string: ill-formed UTF-8 byte";
+                    return token_type::parse_error;
+                }
+            }
+        }
+    }
+
+    static void strtof(float& f, const char* str, char** endptr) noexcept
+    {
+        f = std::strtof(str, endptr);
+    }
+
+    static void strtof(double& f, const char* str, char** endptr) noexcept
+    {
+        f = std::strtod(str, endptr);
+    }
+
+    static void strtof(long double& f, const char* str, char** endptr) noexcept
+    {
+        f = std::strtold(str, endptr);
+    }
+
+    /*!
+    @brief scan a number literal
+
+    This function scans a string according to Sect. 6 of RFC 7159.
+
+    The function is realized with a deterministic finite state machine derived
+    from the grammar described in RFC 7159. Starting in state "init", the
+    input is read and used to determined the next state. Only state "done"
+    accepts the number. State "error" is a trap state to model errors. In the
+    table below, "anything" means any character but the ones listed before.
+
+    state    | 0        | 1-9      | e E      | +       | -       | .        | anything
+    ---------|----------|----------|----------|---------|---------|----------|-----------
+    init     | zero     | any1     | [error]  | [error] | minus   | [error]  | [error]
+    minus    | zero     | any1     | [error]  | [error] | [error] | [error]  | [error]
+    zero     | done     | done     | exponent | done    | done    | decimal1 | done
+    any1     | any1     | any1     | exponent | done    | done    | decimal1 | done
+    decimal1 | decimal2 | [error]  | [error]  | [error] | [error] | [error]  | [error]
+    decimal2 | decimal2 | decimal2 | exponent | done    | done    | done     | done
+    exponent | any2     | any2     | [error]  | sign    | sign    | [error]  | [error]
+    sign     | any2     | any2     | [error]  | [error] | [error] | [error]  | [error]
+    any2     | any2     | any2     | done     | done    | done    | done     | done
+
+    The state machine is realized with one label per state (prefixed with
+    "scan_number_") and `goto` statements between them. The state machine
+    contains cycles, but any cycle can be left when EOF is read. Therefore,
+    the function is guaranteed to terminate.
+
+    During scanning, the read bytes are stored in token_buffer. This string is
+    then converted to a signed integer, an unsigned integer, or a
+    floating-point number.
+
+    @return token_type::value_unsigned, token_type::value_integer, or
+            token_type::value_float if number could be successfully scanned,
+            token_type::parse_error otherwise
+
+    @note The scanner is independent of the current locale. Internally, the
+          locale's decimal point is used instead of `.` to work with the
+          locale-dependent converters.
+    */
+    token_type scan_number()  // lgtm [cpp/use-of-goto]
+    {
+        // reset token_buffer to store the number's bytes
+        reset();
+
+        // the type of the parsed number; initially set to unsigned; will be
+        // changed if minus sign, decimal point or exponent is read
+        token_type number_type = token_type::value_unsigned;
+
+        // state (init): we just found out we need to scan a number
+        switch (current)
+        {
+            case '-':
+            {
+                add(current);
+                goto scan_number_minus;
+            }
+
+            case '0':
+            {
+                add(current);
+                goto scan_number_zero;
+            }
+
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_any1;
+            }
+
+            // LCOV_EXCL_START
+            default:
+            {
+                // all other characters are rejected outside scan_number()
+                assert(false);
+            }
+                // LCOV_EXCL_STOP
+        }
+
+scan_number_minus:
+        // state: we just parsed a leading minus sign
+        number_type = token_type::value_integer;
+        switch (get())
+        {
+            case '0':
+            {
+                add(current);
+                goto scan_number_zero;
+            }
+
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_any1;
+            }
+
+            default:
+            {
+                error_message = "invalid number; expected digit after '-'";
+                return token_type::parse_error;
+            }
+        }
+
+scan_number_zero:
+        // state: we just parse a zero (maybe with a leading minus sign)
+        switch (get())
+        {
+            case '.':
+            {
+                add(decimal_point_char);
+                goto scan_number_decimal1;
+            }
+
+            case 'e':
+            case 'E':
+            {
+                add(current);
+                goto scan_number_exponent;
+            }
+
+            default:
+                goto scan_number_done;
+        }
+
+scan_number_any1:
+        // state: we just parsed a number 0-9 (maybe with a leading minus sign)
+        switch (get())
+        {
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_any1;
+            }
+
+            case '.':
+            {
+                add(decimal_point_char);
+                goto scan_number_decimal1;
+            }
+
+            case 'e':
+            case 'E':
+            {
+                add(current);
+                goto scan_number_exponent;
+            }
+
+            default:
+                goto scan_number_done;
+        }
+
+scan_number_decimal1:
+        // state: we just parsed a decimal point
+        number_type = token_type::value_float;
+        switch (get())
+        {
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_decimal2;
+            }
+
+            default:
+            {
+                error_message = "invalid number; expected digit after '.'";
+                return token_type::parse_error;
+            }
+        }
+
+scan_number_decimal2:
+        // we just parsed at least one number after a decimal point
+        switch (get())
+        {
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_decimal2;
+            }
+
+            case 'e':
+            case 'E':
+            {
+                add(current);
+                goto scan_number_exponent;
+            }
+
+            default:
+                goto scan_number_done;
+        }
+
+scan_number_exponent:
+        // we just parsed an exponent
+        number_type = token_type::value_float;
+        switch (get())
+        {
+            case '+':
+            case '-':
+            {
+                add(current);
+                goto scan_number_sign;
+            }
+
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_any2;
+            }
+
+            default:
+            {
+                error_message =
+                    "invalid number; expected '+', '-', or digit after exponent";
+                return token_type::parse_error;
+            }
+        }
+
+scan_number_sign:
+        // we just parsed an exponent sign
+        switch (get())
+        {
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_any2;
+            }
+
+            default:
+            {
+                error_message = "invalid number; expected digit after exponent sign";
+                return token_type::parse_error;
+            }
+        }
+
+scan_number_any2:
+        // we just parsed a number after the exponent or exponent sign
+        switch (get())
+        {
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+            {
+                add(current);
+                goto scan_number_any2;
+            }
+
+            default:
+                goto scan_number_done;
+        }
+
+scan_number_done:
+        // unget the character after the number (we only read it to know that
+        // we are done scanning a number)
+        unget();
+
+        char* endptr = nullptr;
+        errno = 0;
+
+        // try to parse integers first and fall back to floats
+        if (number_type == token_type::value_unsigned)
+        {
+            const auto x = std::strtoull(token_buffer.data(), &endptr, 10);
+
+            // we checked the number format before
+            assert(endptr == token_buffer.data() + token_buffer.size());
+
+            if (errno == 0)
+            {
+                value_unsigned = static_cast<number_unsigned_t>(x);
+                if (value_unsigned == x)
+                {
+                    return token_type::value_unsigned;
+                }
+            }
+        }
+        else if (number_type == token_type::value_integer)
+        {
+            const auto x = std::strtoll(token_buffer.data(), &endptr, 10);
+
+            // we checked the number format before
+            assert(endptr == token_buffer.data() + token_buffer.size());
+
+            if (errno == 0)
+            {
+                value_integer = static_cast<number_integer_t>(x);
+                if (value_integer == x)
+                {
+                    return token_type::value_integer;
+                }
+            }
+        }
+
+        // this code is reached if we parse a floating-point number or if an
+        // integer conversion above failed
+        strtof(value_float, token_buffer.data(), &endptr);
+
+        // we checked the number format before
+        assert(endptr == token_buffer.data() + token_buffer.size());
+
+        return token_type::value_float;
+    }
+
+    /*!
+    @param[in] literal_text  the literal text to expect
+    @param[in] length        the length of the passed literal text
+    @param[in] return_type   the token type to return on success
+    */
+    token_type scan_literal(const char* literal_text, const std::size_t length,
+                            token_type return_type)
+    {
+        assert(current == literal_text[0]);
+        for (std::size_t i = 1; i < length; ++i)
+        {
+            if (JSON_UNLIKELY(get() != literal_text[i]))
+            {
+                error_message = "invalid literal";
+                return token_type::parse_error;
+            }
+        }
+        return return_type;
+    }
+
+    /////////////////////
+    // input management
+    /////////////////////
+
+    /// reset token_buffer; current character is beginning of token
+    void reset() noexcept
+    {
+        token_buffer.clear();
+        token_string.clear();
+        token_string.push_back(std::char_traits<char>::to_char_type(current));
+    }
+
+    /*
+    @brief get next character from the input
+
+    This function provides the interface to the used input adapter. It does
+    not throw in case the input reached EOF, but returns a
+    `std::char_traits<char>::eof()` in that case.  Stores the scanned characters
+    for use in error messages.
+
+    @return character read from the input
+    */
+    std::char_traits<char>::int_type get()
+    {
+        ++position.chars_read_total;
+        ++position.chars_read_current_line;
+
+        if (next_unget)
+        {
+            // just reset the next_unget variable and work with current
+            next_unget = false;
+        }
+        else
+        {
+            current = ia->get_character();
+        }
+
+        if (JSON_LIKELY(current != std::char_traits<char>::eof()))
+        {
+            token_string.push_back(std::char_traits<char>::to_char_type(current));
+        }
+
+        if (current == '\n')
+        {
+            ++position.lines_read;
+            ++position.chars_read_current_line = 0;
+        }
+
+        return current;
+    }
+
+    /*!
+    @brief unget current character (read it again on next get)
+
+    We implement unget by setting variable next_unget to true. The input is not
+    changed - we just simulate ungetting by modifying chars_read_total,
+    chars_read_current_line, and token_string. The next call to get() will
+    behave as if the unget character is read again.
+    */
+    void unget()
+    {
+        next_unget = true;
+
+        --position.chars_read_total;
+
+        // in case we "unget" a newline, we have to also decrement the lines_read
+        if (position.chars_read_current_line == 0)
+        {
+            if (position.lines_read > 0)
+            {
+                --position.lines_read;
+            }
+        }
+        else
+        {
+            --position.chars_read_current_line;
+        }
+
+        if (JSON_LIKELY(current != std::char_traits<char>::eof()))
+        {
+            assert(token_string.size() != 0);
+            token_string.pop_back();
+        }
+    }
+
+    /// add a character to token_buffer
+    void add(int c)
+    {
+        token_buffer.push_back(std::char_traits<char>::to_char_type(c));
+    }
+
+  public:
+    /////////////////////
+    // value getters
+    /////////////////////
+
+    /// return integer value
+    constexpr number_integer_t get_number_integer() const noexcept
+    {
+        return value_integer;
+    }
+
+    /// return unsigned integer value
+    constexpr number_unsigned_t get_number_unsigned() const noexcept
+    {
+        return value_unsigned;
+    }
+
+    /// return floating-point value
+    constexpr number_float_t get_number_float() const noexcept
+    {
+        return value_float;
+    }
+
+    /// return current string value (implicitly resets the token; useful only once)
+    string_t& get_string()
+    {
+        return token_buffer;
+    }
+
+    /////////////////////
+    // diagnostics
+    /////////////////////
+
+    /// return position of last read token
+    constexpr position_t get_position() const noexcept
+    {
+        return position;
+    }
+
+    /// return the last read token (for errors only).  Will never contain EOF
+    /// (an arbitrary value that is not a valid char value, often -1), because
+    /// 255 may legitimately occur.  May contain NUL, which should be escaped.
+    std::string get_token_string() const
+    {
+        // escape control characters
+        std::string result;
+        for (const auto c : token_string)
+        {
+            if ('\x00' <= c and c <= '\x1F')
+            {
+                // escape control characters
+                char cs[9];
+                (std::snprintf)(cs, 9, "<U+%.4X>", static_cast<unsigned char>(c));
+                result += cs;
+            }
+            else
+            {
+                // add character as is
+                result.push_back(c);
+            }
+        }
+
+        return result;
+    }
+
+    /// return syntax error message
+    constexpr const char* get_error_message() const noexcept
+    {
+        return error_message;
+    }
+
+    /////////////////////
+    // actual scanner
+    /////////////////////
+
+    /*!
+    @brief skip the UTF-8 byte order mark
+    @return true iff there is no BOM or the correct BOM has been skipped
+    */
+    bool skip_bom()
+    {
+        if (get() == 0xEF)
+        {
+            // check if we completely parse the BOM
+            return get() == 0xBB and get() == 0xBF;
+        }
+
+        // the first character is not the beginning of the BOM; unget it to
+        // process is later
+        unget();
+        return true;
+    }
+
+    token_type scan()
+    {
+        // initially, skip the BOM
+        if (position.chars_read_total == 0 and not skip_bom())
+        {
+            error_message = "invalid BOM; must be 0xEF 0xBB 0xBF if given";
+            return token_type::parse_error;
+        }
+
+        // read next character and ignore whitespace
+        do
+        {
+            get();
+        }
+        while (current == ' ' or current == '\t' or current == '\n' or current == '\r');
+
+        switch (current)
+        {
+            // structural characters
+            case '[':
+                return token_type::begin_array;
+            case ']':
+                return token_type::end_array;
+            case '{':
+                return token_type::begin_object;
+            case '}':
+                return token_type::end_object;
+            case ':':
+                return token_type::name_separator;
+            case ',':
+                return token_type::value_separator;
+
+            // literals
+            case 't':
+                return scan_literal("true", 4, token_type::literal_true);
+            case 'f':
+                return scan_literal("false", 5, token_type::literal_false);
+            case 'n':
+                return scan_literal("null", 4, token_type::literal_null);
+
+            // string
+            case '\"':
+                return scan_string();
+
+            // number
+            case '-':
+            case '0':
+            case '1':
+            case '2':
+            case '3':
+            case '4':
+            case '5':
+            case '6':
+            case '7':
+            case '8':
+            case '9':
+                return scan_number();
+
+            // end of input (the null byte is needed when parsing from
+            // string literals)
+            case '\0':
+            case std::char_traits<char>::eof():
+                return token_type::end_of_input;
+
+            // error
+            default:
+                error_message = "invalid literal";
+                return token_type::parse_error;
+        }
+    }
+
+  private:
+    /// input adapter
+    detail::input_adapter_t ia = nullptr;
+
+    /// the current character
+    std::char_traits<char>::int_type current = std::char_traits<char>::eof();
+
+    /// whether the next get() call should just return current
+    bool next_unget = false;
+
+    /// the start position of the current token
+    position_t position;
+
+    /// raw input token string (for error messages)
+    std::vector<char> token_string {};
+
+    /// buffer for variable-length tokens (numbers, strings)
+    string_t token_buffer {};
+
+    /// a description of occurred lexer errors
+    const char* error_message = "";
+
+    // number values
+    number_integer_t value_integer = 0;
+    number_unsigned_t value_unsigned = 0;
+    number_float_t value_float = 0;
+
+    /// the decimal point
+    const char decimal_point_char = '.';
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/input/parser.hpp>
+
+
+#include <cassert> // assert
+#include <cmath> // isfinite
+#include <cstdint> // uint8_t
+#include <functional> // function
+#include <string> // string
+#include <utility> // move
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/meta/is_sax.hpp>
+
+
+#include <cstdint> // size_t
+#include <utility> // declval
+
+// #include <nlohmann/detail/meta/detected.hpp>
+
+// #include <nlohmann/detail/meta/type_traits.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+template <typename T>
+using null_function_t = decltype(std::declval<T&>().null());
+
+template <typename T>
+using boolean_function_t =
+    decltype(std::declval<T&>().boolean(std::declval<bool>()));
+
+template <typename T, typename Integer>
+using number_integer_function_t =
+    decltype(std::declval<T&>().number_integer(std::declval<Integer>()));
+
+template <typename T, typename Unsigned>
+using number_unsigned_function_t =
+    decltype(std::declval<T&>().number_unsigned(std::declval<Unsigned>()));
+
+template <typename T, typename Float, typename String>
+using number_float_function_t = decltype(std::declval<T&>().number_float(
+                                    std::declval<Float>(), std::declval<const String&>()));
+
+template <typename T, typename String>
+using string_function_t =
+    decltype(std::declval<T&>().string(std::declval<String&>()));
+
+template <typename T>
+using start_object_function_t =
+    decltype(std::declval<T&>().start_object(std::declval<std::size_t>()));
+
+template <typename T, typename String>
+using key_function_t =
+    decltype(std::declval<T&>().key(std::declval<String&>()));
+
+template <typename T>
+using end_object_function_t = decltype(std::declval<T&>().end_object());
+
+template <typename T>
+using start_array_function_t =
+    decltype(std::declval<T&>().start_array(std::declval<std::size_t>()));
+
+template <typename T>
+using end_array_function_t = decltype(std::declval<T&>().end_array());
+
+template <typename T, typename Exception>
+using parse_error_function_t = decltype(std::declval<T&>().parse_error(
+        std::declval<std::size_t>(), std::declval<const std::string&>(),
+        std::declval<const Exception&>()));
+
+template <typename SAX, typename BasicJsonType>
+struct is_sax
+{
+  private:
+    static_assert(is_basic_json<BasicJsonType>::value,
+                  "BasicJsonType must be of type basic_json<...>");
+
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+    using exception_t = typename BasicJsonType::exception;
+
+  public:
+    static constexpr bool value =
+        is_detected_exact<bool, null_function_t, SAX>::value &&
+        is_detected_exact<bool, boolean_function_t, SAX>::value &&
+        is_detected_exact<bool, number_integer_function_t, SAX,
+        number_integer_t>::value &&
+        is_detected_exact<bool, number_unsigned_function_t, SAX,
+        number_unsigned_t>::value &&
+        is_detected_exact<bool, number_float_function_t, SAX, number_float_t,
+        string_t>::value &&
+        is_detected_exact<bool, string_function_t, SAX, string_t>::value &&
+        is_detected_exact<bool, start_object_function_t, SAX>::value &&
+        is_detected_exact<bool, key_function_t, SAX, string_t>::value &&
+        is_detected_exact<bool, end_object_function_t, SAX>::value &&
+        is_detected_exact<bool, start_array_function_t, SAX>::value &&
+        is_detected_exact<bool, end_array_function_t, SAX>::value &&
+        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value;
+};
+
+template <typename SAX, typename BasicJsonType>
+struct is_sax_static_asserts
+{
+  private:
+    static_assert(is_basic_json<BasicJsonType>::value,
+                  "BasicJsonType must be of type basic_json<...>");
+
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+    using exception_t = typename BasicJsonType::exception;
+
+  public:
+    static_assert(is_detected_exact<bool, null_function_t, SAX>::value,
+                  "Missing/invalid function: bool null()");
+    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
+                  "Missing/invalid function: bool boolean(bool)");
+    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
+                  "Missing/invalid function: bool boolean(bool)");
+    static_assert(
+        is_detected_exact<bool, number_integer_function_t, SAX,
+        number_integer_t>::value,
+        "Missing/invalid function: bool number_integer(number_integer_t)");
+    static_assert(
+        is_detected_exact<bool, number_unsigned_function_t, SAX,
+        number_unsigned_t>::value,
+        "Missing/invalid function: bool number_unsigned(number_unsigned_t)");
+    static_assert(is_detected_exact<bool, number_float_function_t, SAX,
+                  number_float_t, string_t>::value,
+                  "Missing/invalid function: bool number_float(number_float_t, const string_t&)");
+    static_assert(
+        is_detected_exact<bool, string_function_t, SAX, string_t>::value,
+        "Missing/invalid function: bool string(string_t&)");
+    static_assert(is_detected_exact<bool, start_object_function_t, SAX>::value,
+                  "Missing/invalid function: bool start_object(std::size_t)");
+    static_assert(is_detected_exact<bool, key_function_t, SAX, string_t>::value,
+                  "Missing/invalid function: bool key(string_t&)");
+    static_assert(is_detected_exact<bool, end_object_function_t, SAX>::value,
+                  "Missing/invalid function: bool end_object()");
+    static_assert(is_detected_exact<bool, start_array_function_t, SAX>::value,
+                  "Missing/invalid function: bool start_array(std::size_t)");
+    static_assert(is_detected_exact<bool, end_array_function_t, SAX>::value,
+                  "Missing/invalid function: bool end_array()");
+    static_assert(
+        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value,
+        "Missing/invalid function: bool parse_error(std::size_t, const "
+        "std::string&, const exception&)");
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/input/input_adapters.hpp>
+
+// #include <nlohmann/detail/input/json_sax.hpp>
+
+
+#include <cstddef>
+#include <string>
+#include <vector>
+
+// #include <nlohmann/detail/input/parser.hpp>
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+
+namespace nlohmann
+{
+
+/*!
+@brief SAX interface
+
+This class describes the SAX interface used by @ref nlohmann::json::sax_parse.
+Each function is called in different situations while the input is parsed. The
+boolean return value informs the parser whether to continue processing the
+input.
+*/
+template<typename BasicJsonType>
+struct json_sax
+{
+    /// type for (signed) integers
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    /// type for unsigned integers
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    /// type for floating-point numbers
+    using number_float_t = typename BasicJsonType::number_float_t;
+    /// type for strings
+    using string_t = typename BasicJsonType::string_t;
+
+    /*!
+    @brief a null value was read
+    @return whether parsing should proceed
+    */
+    virtual bool null() = 0;
+
+    /*!
+    @brief a boolean value was read
+    @param[in] val  boolean value
+    @return whether parsing should proceed
+    */
+    virtual bool boolean(bool val) = 0;
+
+    /*!
+    @brief an integer number was read
+    @param[in] val  integer value
+    @return whether parsing should proceed
+    */
+    virtual bool number_integer(number_integer_t val) = 0;
+
+    /*!
+    @brief an unsigned integer number was read
+    @param[in] val  unsigned integer value
+    @return whether parsing should proceed
+    */
+    virtual bool number_unsigned(number_unsigned_t val) = 0;
+
+    /*!
+    @brief an floating-point number was read
+    @param[in] val  floating-point value
+    @param[in] s    raw token value
+    @return whether parsing should proceed
+    */
+    virtual bool number_float(number_float_t val, const string_t& s) = 0;
+
+    /*!
+    @brief a string was read
+    @param[in] val  string value
+    @return whether parsing should proceed
+    @note It is safe to move the passed string.
+    */
+    virtual bool string(string_t& val) = 0;
+
+    /*!
+    @brief the beginning of an object was read
+    @param[in] elements  number of object elements or -1 if unknown
+    @return whether parsing should proceed
+    @note binary formats may report the number of elements
+    */
+    virtual bool start_object(std::size_t elements) = 0;
+
+    /*!
+    @brief an object key was read
+    @param[in] val  object key
+    @return whether parsing should proceed
+    @note It is safe to move the passed string.
+    */
+    virtual bool key(string_t& val) = 0;
+
+    /*!
+    @brief the end of an object was read
+    @return whether parsing should proceed
+    */
+    virtual bool end_object() = 0;
+
+    /*!
+    @brief the beginning of an array was read
+    @param[in] elements  number of array elements or -1 if unknown
+    @return whether parsing should proceed
+    @note binary formats may report the number of elements
+    */
+    virtual bool start_array(std::size_t elements) = 0;
+
+    /*!
+    @brief the end of an array was read
+    @return whether parsing should proceed
+    */
+    virtual bool end_array() = 0;
+
+    /*!
+    @brief a parse error occurred
+    @param[in] position    the position in the input where the error occurs
+    @param[in] last_token  the last read token
+    @param[in] ex          an exception object describing the error
+    @return whether parsing should proceed (must return false)
+    */
+    virtual bool parse_error(std::size_t position,
+                             const std::string& last_token,
+                             const detail::exception& ex) = 0;
+
+    virtual ~json_sax() = default;
+};
+
+
+namespace detail
+{
+/*!
+@brief SAX implementation to create a JSON value from SAX events
+
+This class implements the @ref json_sax interface and processes the SAX events
+to create a JSON value which makes it basically a DOM parser. The structure or
+hierarchy of the JSON value is managed by the stack `ref_stack` which contains
+a pointer to the respective array or object for each recursion depth.
+
+After successful parsing, the value that is passed by reference to the
+constructor contains the parsed value.
+
+@tparam BasicJsonType  the JSON type
+*/
+template<typename BasicJsonType>
+class json_sax_dom_parser
+{
+  public:
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+
+    /*!
+    @param[in, out] r  reference to a JSON value that is manipulated while
+                       parsing
+    @param[in] allow_exceptions_  whether parse errors yield exceptions
+    */
+    explicit json_sax_dom_parser(BasicJsonType& r, const bool allow_exceptions_ = true)
+        : root(r), allow_exceptions(allow_exceptions_)
+    {}
+
+    bool null()
+    {
+        handle_value(nullptr);
+        return true;
+    }
+
+    bool boolean(bool val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool number_integer(number_integer_t val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool number_unsigned(number_unsigned_t val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool number_float(number_float_t val, const string_t& /*unused*/)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool string(string_t& val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool start_object(std::size_t len)
+    {
+        ref_stack.push_back(handle_value(BasicJsonType::value_t::object));
+
+        if (JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
+        {
+            JSON_THROW(out_of_range::create(408,
+                                            "excessive object size: " + std::to_string(len)));
+        }
+
+        return true;
+    }
+
+    bool key(string_t& val)
+    {
+        // add null at given key and store the reference for later
+        object_element = &(ref_stack.back()->m_value.object->operator[](val));
+        return true;
+    }
+
+    bool end_object()
+    {
+        ref_stack.pop_back();
+        return true;
+    }
+
+    bool start_array(std::size_t len)
+    {
+        ref_stack.push_back(handle_value(BasicJsonType::value_t::array));
+
+        if (JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
+        {
+            JSON_THROW(out_of_range::create(408,
+                                            "excessive array size: " + std::to_string(len)));
+        }
+
+        return true;
+    }
+
+    bool end_array()
+    {
+        ref_stack.pop_back();
+        return true;
+    }
+
+    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/,
+                     const detail::exception& ex)
+    {
+        errored = true;
+        if (allow_exceptions)
+        {
+            // determine the proper exception type from the id
+            switch ((ex.id / 100) % 100)
+            {
+                case 1:
+                    JSON_THROW(*reinterpret_cast<const detail::parse_error*>(&ex));
+                case 4:
+                    JSON_THROW(*reinterpret_cast<const detail::out_of_range*>(&ex));
+                // LCOV_EXCL_START
+                case 2:
+                    JSON_THROW(*reinterpret_cast<const detail::invalid_iterator*>(&ex));
+                case 3:
+                    JSON_THROW(*reinterpret_cast<const detail::type_error*>(&ex));
+                case 5:
+                    JSON_THROW(*reinterpret_cast<const detail::other_error*>(&ex));
+                default:
+                    assert(false);
+                    // LCOV_EXCL_STOP
+            }
+        }
+        return false;
+    }
+
+    constexpr bool is_errored() const
+    {
+        return errored;
+    }
+
+  private:
+    /*!
+    @invariant If the ref stack is empty, then the passed value will be the new
+               root.
+    @invariant If the ref stack contains a value, then it is an array or an
+               object to which we can add elements
+    */
+    template<typename Value>
+    BasicJsonType* handle_value(Value&& v)
+    {
+        if (ref_stack.empty())
+        {
+            root = BasicJsonType(std::forward<Value>(v));
+            return &root;
+        }
+
+        assert(ref_stack.back()->is_array() or ref_stack.back()->is_object());
+
+        if (ref_stack.back()->is_array())
+        {
+            ref_stack.back()->m_value.array->emplace_back(std::forward<Value>(v));
+            return &(ref_stack.back()->m_value.array->back());
+        }
+        else
+        {
+            assert(object_element);
+            *object_element = BasicJsonType(std::forward<Value>(v));
+            return object_element;
+        }
+    }
+
+    /// the parsed JSON value
+    BasicJsonType& root;
+    /// stack to model hierarchy of values
+    std::vector<BasicJsonType*> ref_stack;
+    /// helper to hold the reference for the next object element
+    BasicJsonType* object_element = nullptr;
+    /// whether a syntax error occurred
+    bool errored = false;
+    /// whether to throw exceptions in case of errors
+    const bool allow_exceptions = true;
+};
+
+template<typename BasicJsonType>
+class json_sax_dom_callback_parser
+{
+  public:
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+    using parser_callback_t = typename BasicJsonType::parser_callback_t;
+    using parse_event_t = typename BasicJsonType::parse_event_t;
+
+    json_sax_dom_callback_parser(BasicJsonType& r,
+                                 const parser_callback_t cb,
+                                 const bool allow_exceptions_ = true)
+        : root(r), callback(cb), allow_exceptions(allow_exceptions_)
+    {
+        keep_stack.push_back(true);
+    }
+
+    bool null()
+    {
+        handle_value(nullptr);
+        return true;
+    }
+
+    bool boolean(bool val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool number_integer(number_integer_t val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool number_unsigned(number_unsigned_t val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool number_float(number_float_t val, const string_t& /*unused*/)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool string(string_t& val)
+    {
+        handle_value(val);
+        return true;
+    }
+
+    bool start_object(std::size_t len)
+    {
+        // check callback for object start
+        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::object_start, discarded);
+        keep_stack.push_back(keep);
+
+        auto val = handle_value(BasicJsonType::value_t::object, true);
+        ref_stack.push_back(val.second);
+
+        // check object limit
+        if (ref_stack.back())
+        {
+            if (JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
+            {
+                JSON_THROW(out_of_range::create(408,
+                                                "excessive object size: " + std::to_string(len)));
+            }
+        }
+
+        return true;
+    }
+
+    bool key(string_t& val)
+    {
+        BasicJsonType k = BasicJsonType(val);
+
+        // check callback for key
+        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::key, k);
+        key_keep_stack.push_back(keep);
+
+        // add discarded value at given key and store the reference for later
+        if (keep and ref_stack.back())
+        {
+            object_element = &(ref_stack.back()->m_value.object->operator[](val) = discarded);
+        }
+
+        return true;
+    }
+
+    bool end_object()
+    {
+        if (ref_stack.back())
+        {
+            if (not callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::object_end, *ref_stack.back()))
+            {
+                // discard object
+                *ref_stack.back() = discarded;
+            }
+        }
+
+        assert(not ref_stack.empty());
+        assert(not keep_stack.empty());
+        ref_stack.pop_back();
+        keep_stack.pop_back();
+
+        if (not ref_stack.empty() and ref_stack.back())
+        {
+            // remove discarded value
+            if (ref_stack.back()->is_object())
+            {
+                for (auto it = ref_stack.back()->begin(); it != ref_stack.back()->end(); ++it)
+                {
+                    if (it->is_discarded())
+                    {
+                        ref_stack.back()->erase(it);
+                        break;
+                    }
+                }
+            }
+        }
+
+        return true;
+    }
+
+    bool start_array(std::size_t len)
+    {
+        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::array_start, discarded);
+        keep_stack.push_back(keep);
+
+        auto val = handle_value(BasicJsonType::value_t::array, true);
+        ref_stack.push_back(val.second);
+
+        // check array limit
+        if (ref_stack.back())
+        {
+            if (JSON_UNLIKELY(len != std::size_t(-1) and len > ref_stack.back()->max_size()))
+            {
+                JSON_THROW(out_of_range::create(408,
+                                                "excessive array size: " + std::to_string(len)));
+            }
+        }
+
+        return true;
+    }
+
+    bool end_array()
+    {
+        bool keep = true;
+
+        if (ref_stack.back())
+        {
+            keep = callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::array_end, *ref_stack.back());
+            if (not keep)
+            {
+                // discard array
+                *ref_stack.back() = discarded;
+            }
+        }
+
+        assert(not ref_stack.empty());
+        assert(not keep_stack.empty());
+        ref_stack.pop_back();
+        keep_stack.pop_back();
+
+        // remove discarded value
+        if (not keep and not ref_stack.empty())
+        {
+            if (ref_stack.back()->is_array())
+            {
+                ref_stack.back()->m_value.array->pop_back();
+            }
+        }
+
+        return true;
+    }
+
+    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/,
+                     const detail::exception& ex)
+    {
+        errored = true;
+        if (allow_exceptions)
+        {
+            // determine the proper exception type from the id
+            switch ((ex.id / 100) % 100)
+            {
+                case 1:
+                    JSON_THROW(*reinterpret_cast<const detail::parse_error*>(&ex));
+                case 4:
+                    JSON_THROW(*reinterpret_cast<const detail::out_of_range*>(&ex));
+                // LCOV_EXCL_START
+                case 2:
+                    JSON_THROW(*reinterpret_cast<const detail::invalid_iterator*>(&ex));
+                case 3:
+                    JSON_THROW(*reinterpret_cast<const detail::type_error*>(&ex));
+                case 5:
+                    JSON_THROW(*reinterpret_cast<const detail::other_error*>(&ex));
+                default:
+                    assert(false);
+                    // LCOV_EXCL_STOP
+            }
+        }
+        return false;
+    }
+
+    constexpr bool is_errored() const
+    {
+        return errored;
+    }
+
+  private:
+    /*!
+    @param[in] v  value to add to the JSON value we build during parsing
+    @param[in] skip_callback  whether we should skip calling the callback
+               function; this is required after start_array() and
+               start_object() SAX events, because otherwise we would call the
+               callback function with an empty array or object, respectively.
+
+    @invariant If the ref stack is empty, then the passed value will be the new
+               root.
+    @invariant If the ref stack contains a value, then it is an array or an
+               object to which we can add elements
+
+    @return pair of boolean (whether value should be kept) and pointer (to the
+            passed value in the ref_stack hierarchy; nullptr if not kept)
+    */
+    template<typename Value>
+    std::pair<bool, BasicJsonType*> handle_value(Value&& v, const bool skip_callback = false)
+    {
+        assert(not keep_stack.empty());
+
+        // do not handle this value if we know it would be added to a discarded
+        // container
+        if (not keep_stack.back())
+        {
+            return {false, nullptr};
+        }
+
+        // create value
+        auto value = BasicJsonType(std::forward<Value>(v));
+
+        // check callback
+        const bool keep = skip_callback or callback(static_cast<int>(ref_stack.size()), parse_event_t::value, value);
+
+        // do not handle this value if we just learnt it shall be discarded
+        if (not keep)
+        {
+            return {false, nullptr};
+        }
+
+        if (ref_stack.empty())
+        {
+            root = std::move(value);
+            return {true, &root};
+        }
+
+        // skip this value if we already decided to skip the parent
+        // (https://github.com/nlohmann/json/issues/971#issuecomment-413678360)
+        if (not ref_stack.back())
+        {
+            return {false, nullptr};
+        }
+
+        // we now only expect arrays and objects
+        assert(ref_stack.back()->is_array() or ref_stack.back()->is_object());
+
+        if (ref_stack.back()->is_array())
+        {
+            ref_stack.back()->m_value.array->push_back(std::move(value));
+            return {true, &(ref_stack.back()->m_value.array->back())};
+        }
+        else
+        {
+            // check if we should store an element for the current key
+            assert(not key_keep_stack.empty());
+            const bool store_element = key_keep_stack.back();
+            key_keep_stack.pop_back();
+
+            if (not store_element)
+            {
+                return {false, nullptr};
+            }
+
+            assert(object_element);
+            *object_element = std::move(value);
+            return {true, object_element};
+        }
+    }
+
+    /// the parsed JSON value
+    BasicJsonType& root;
+    /// stack to model hierarchy of values
+    std::vector<BasicJsonType*> ref_stack;
+    /// stack to manage which values to keep
+    std::vector<bool> keep_stack;
+    /// stack to manage which object keys to keep
+    std::vector<bool> key_keep_stack;
+    /// helper to hold the reference for the next object element
+    BasicJsonType* object_element = nullptr;
+    /// whether a syntax error occurred
+    bool errored = false;
+    /// callback function
+    const parser_callback_t callback = nullptr;
+    /// whether to throw exceptions in case of errors
+    const bool allow_exceptions = true;
+    /// a discarded value for the callback
+    BasicJsonType discarded = BasicJsonType::value_t::discarded;
+};
+
+template<typename BasicJsonType>
+class json_sax_acceptor
+{
+  public:
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+
+    bool null()
+    {
+        return true;
+    }
+
+    bool boolean(bool /*unused*/)
+    {
+        return true;
+    }
+
+    bool number_integer(number_integer_t /*unused*/)
+    {
+        return true;
+    }
+
+    bool number_unsigned(number_unsigned_t /*unused*/)
+    {
+        return true;
+    }
+
+    bool number_float(number_float_t /*unused*/, const string_t& /*unused*/)
+    {
+        return true;
+    }
+
+    bool string(string_t& /*unused*/)
+    {
+        return true;
+    }
+
+    bool start_object(std::size_t  /*unused*/ = std::size_t(-1))
+    {
+        return true;
+    }
+
+    bool key(string_t& /*unused*/)
+    {
+        return true;
+    }
+
+    bool end_object()
+    {
+        return true;
+    }
+
+    bool start_array(std::size_t  /*unused*/ = std::size_t(-1))
+    {
+        return true;
+    }
+
+    bool end_array()
+    {
+        return true;
+    }
+
+    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/, const detail::exception& /*unused*/)
+    {
+        return false;
+    }
+};
+}  // namespace detail
+
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/input/lexer.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+////////////
+// parser //
+////////////
+
+/*!
+@brief syntax analysis
+
+This class implements a recursive decent parser.
+*/
+template<typename BasicJsonType>
+class parser
+{
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+    using lexer_t = lexer<BasicJsonType>;
+    using token_type = typename lexer_t::token_type;
+
+  public:
+    enum class parse_event_t : uint8_t
+    {
+        /// the parser read `{` and started to process a JSON object
+        object_start,
+        /// the parser read `}` and finished processing a JSON object
+        object_end,
+        /// the parser read `[` and started to process a JSON array
+        array_start,
+        /// the parser read `]` and finished processing a JSON array
+        array_end,
+        /// the parser read a key of a value in an object
+        key,
+        /// the parser finished reading a JSON value
+        value
+    };
+
+    using parser_callback_t =
+        std::function<bool(int depth, parse_event_t event, BasicJsonType& parsed)>;
+
+    /// a parser reading from an input adapter
+    explicit parser(detail::input_adapter_t&& adapter,
+                    const parser_callback_t cb = nullptr,
+                    const bool allow_exceptions_ = true)
+        : callback(cb), m_lexer(std::move(adapter)), allow_exceptions(allow_exceptions_)
+    {
+        // read first token
+        get_token();
+    }
+
+    /*!
+    @brief public parser interface
+
+    @param[in] strict      whether to expect the last token to be EOF
+    @param[in,out] result  parsed JSON value
+
+    @throw parse_error.101 in case of an unexpected token
+    @throw parse_error.102 if to_unicode fails or surrogate error
+    @throw parse_error.103 if to_unicode fails
+    */
+    void parse(const bool strict, BasicJsonType& result)
+    {
+        if (callback)
+        {
+            json_sax_dom_callback_parser<BasicJsonType> sdp(result, callback, allow_exceptions);
+            sax_parse_internal(&sdp);
+            result.assert_invariant();
+
+            // in strict mode, input must be completely read
+            if (strict and (get_token() != token_type::end_of_input))
+            {
+                sdp.parse_error(m_lexer.get_position(),
+                                m_lexer.get_token_string(),
+                                parse_error::create(101, m_lexer.get_position(),
+                                                    exception_message(token_type::end_of_input, "value")));
+            }
+
+            // in case of an error, return discarded value
+            if (sdp.is_errored())
+            {
+                result = value_t::discarded;
+                return;
+            }
+
+            // set top-level value to null if it was discarded by the callback
+            // function
+            if (result.is_discarded())
+            {
+                result = nullptr;
+            }
+        }
+        else
+        {
+            json_sax_dom_parser<BasicJsonType> sdp(result, allow_exceptions);
+            sax_parse_internal(&sdp);
+            result.assert_invariant();
+
+            // in strict mode, input must be completely read
+            if (strict and (get_token() != token_type::end_of_input))
+            {
+                sdp.parse_error(m_lexer.get_position(),
+                                m_lexer.get_token_string(),
+                                parse_error::create(101, m_lexer.get_position(),
+                                                    exception_message(token_type::end_of_input, "value")));
+            }
+
+            // in case of an error, return discarded value
+            if (sdp.is_errored())
+            {
+                result = value_t::discarded;
+                return;
+            }
+        }
+    }
+
+    /*!
+    @brief public accept interface
+
+    @param[in] strict  whether to expect the last token to be EOF
+    @return whether the input is a proper JSON text
+    */
+    bool accept(const bool strict = true)
+    {
+        json_sax_acceptor<BasicJsonType> sax_acceptor;
+        return sax_parse(&sax_acceptor, strict);
+    }
+
+    template <typename SAX>
+    bool sax_parse(SAX* sax, const bool strict = true)
+    {
+        (void)detail::is_sax_static_asserts<SAX, BasicJsonType> {};
+        const bool result = sax_parse_internal(sax);
+
+        // strict mode: next byte must be EOF
+        if (result and strict and (get_token() != token_type::end_of_input))
+        {
+            return sax->parse_error(m_lexer.get_position(),
+                                    m_lexer.get_token_string(),
+                                    parse_error::create(101, m_lexer.get_position(),
+                                            exception_message(token_type::end_of_input, "value")));
+        }
+
+        return result;
+    }
+
+  private:
+    template <typename SAX>
+    bool sax_parse_internal(SAX* sax)
+    {
+        // stack to remember the hierarchy of structured values we are parsing
+        // true = array; false = object
+        std::vector<bool> states;
+        // value to avoid a goto (see comment where set to true)
+        bool skip_to_state_evaluation = false;
+
+        while (true)
+        {
+            if (not skip_to_state_evaluation)
+            {
+                // invariant: get_token() was called before each iteration
+                switch (last_token)
+                {
+                    case token_type::begin_object:
+                    {
+                        if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
+                        {
+                            return false;
+                        }
+
+                        // closing } -> we are done
+                        if (get_token() == token_type::end_object)
+                        {
+                            if (JSON_UNLIKELY(not sax->end_object()))
+                            {
+                                return false;
+                            }
+                            break;
+                        }
+
+                        // parse key
+                        if (JSON_UNLIKELY(last_token != token_type::value_string))
+                        {
+                            return sax->parse_error(m_lexer.get_position(),
+                                                    m_lexer.get_token_string(),
+                                                    parse_error::create(101, m_lexer.get_position(),
+                                                            exception_message(token_type::value_string, "object key")));
+                        }
+                        if (JSON_UNLIKELY(not sax->key(m_lexer.get_string())))
+                        {
+                            return false;
+                        }
+
+                        // parse separator (:)
+                        if (JSON_UNLIKELY(get_token() != token_type::name_separator))
+                        {
+                            return sax->parse_error(m_lexer.get_position(),
+                                                    m_lexer.get_token_string(),
+                                                    parse_error::create(101, m_lexer.get_position(),
+                                                            exception_message(token_type::name_separator, "object separator")));
+                        }
+
+                        // remember we are now inside an object
+                        states.push_back(false);
+
+                        // parse values
+                        get_token();
+                        continue;
+                    }
+
+                    case token_type::begin_array:
+                    {
+                        if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
+                        {
+                            return false;
+                        }
+
+                        // closing ] -> we are done
+                        if (get_token() == token_type::end_array)
+                        {
+                            if (JSON_UNLIKELY(not sax->end_array()))
+                            {
+                                return false;
+                            }
+                            break;
+                        }
+
+                        // remember we are now inside an array
+                        states.push_back(true);
+
+                        // parse values (no need to call get_token)
+                        continue;
+                    }
+
+                    case token_type::value_float:
+                    {
+                        const auto res = m_lexer.get_number_float();
+
+                        if (JSON_UNLIKELY(not std::isfinite(res)))
+                        {
+                            return sax->parse_error(m_lexer.get_position(),
+                                                    m_lexer.get_token_string(),
+                                                    out_of_range::create(406, "number overflow parsing '" + m_lexer.get_token_string() + "'"));
+                        }
+                        else
+                        {
+                            if (JSON_UNLIKELY(not sax->number_float(res, m_lexer.get_string())))
+                            {
+                                return false;
+                            }
+                            break;
+                        }
+                    }
+
+                    case token_type::literal_false:
+                    {
+                        if (JSON_UNLIKELY(not sax->boolean(false)))
+                        {
+                            return false;
+                        }
+                        break;
+                    }
+
+                    case token_type::literal_null:
+                    {
+                        if (JSON_UNLIKELY(not sax->null()))
+                        {
+                            return false;
+                        }
+                        break;
+                    }
+
+                    case token_type::literal_true:
+                    {
+                        if (JSON_UNLIKELY(not sax->boolean(true)))
+                        {
+                            return false;
+                        }
+                        break;
+                    }
+
+                    case token_type::value_integer:
+                    {
+                        if (JSON_UNLIKELY(not sax->number_integer(m_lexer.get_number_integer())))
+                        {
+                            return false;
+                        }
+                        break;
+                    }
+
+                    case token_type::value_string:
+                    {
+                        if (JSON_UNLIKELY(not sax->string(m_lexer.get_string())))
+                        {
+                            return false;
+                        }
+                        break;
+                    }
+
+                    case token_type::value_unsigned:
+                    {
+                        if (JSON_UNLIKELY(not sax->number_unsigned(m_lexer.get_number_unsigned())))
+                        {
+                            return false;
+                        }
+                        break;
+                    }
+
+                    case token_type::parse_error:
+                    {
+                        // using "uninitialized" to avoid "expected" message
+                        return sax->parse_error(m_lexer.get_position(),
+                                                m_lexer.get_token_string(),
+                                                parse_error::create(101, m_lexer.get_position(),
+                                                        exception_message(token_type::uninitialized, "value")));
+                    }
+
+                    default: // the last token was unexpected
+                    {
+                        return sax->parse_error(m_lexer.get_position(),
+                                                m_lexer.get_token_string(),
+                                                parse_error::create(101, m_lexer.get_position(),
+                                                        exception_message(token_type::literal_or_value, "value")));
+                    }
+                }
+            }
+            else
+            {
+                skip_to_state_evaluation = false;
+            }
+
+            // we reached this line after we successfully parsed a value
+            if (states.empty())
+            {
+                // empty stack: we reached the end of the hierarchy: done
+                return true;
+            }
+            else
+            {
+                if (states.back())  // array
+                {
+                    // comma -> next value
+                    if (get_token() == token_type::value_separator)
+                    {
+                        // parse a new value
+                        get_token();
+                        continue;
+                    }
+
+                    // closing ]
+                    if (JSON_LIKELY(last_token == token_type::end_array))
+                    {
+                        if (JSON_UNLIKELY(not sax->end_array()))
+                        {
+                            return false;
+                        }
+
+                        // We are done with this array. Before we can parse a
+                        // new value, we need to evaluate the new state first.
+                        // By setting skip_to_state_evaluation to false, we
+                        // are effectively jumping to the beginning of this if.
+                        assert(not states.empty());
+                        states.pop_back();
+                        skip_to_state_evaluation = true;
+                        continue;
+                    }
+                    else
+                    {
+                        return sax->parse_error(m_lexer.get_position(),
+                                                m_lexer.get_token_string(),
+                                                parse_error::create(101, m_lexer.get_position(),
+                                                        exception_message(token_type::end_array, "array")));
+                    }
+                }
+                else  // object
+                {
+                    // comma -> next value
+                    if (get_token() == token_type::value_separator)
+                    {
+                        // parse key
+                        if (JSON_UNLIKELY(get_token() != token_type::value_string))
+                        {
+                            return sax->parse_error(m_lexer.get_position(),
+                                                    m_lexer.get_token_string(),
+                                                    parse_error::create(101, m_lexer.get_position(),
+                                                            exception_message(token_type::value_string, "object key")));
+                        }
+                        else
+                        {
+                            if (JSON_UNLIKELY(not sax->key(m_lexer.get_string())))
+                            {
+                                return false;
+                            }
+                        }
+
+                        // parse separator (:)
+                        if (JSON_UNLIKELY(get_token() != token_type::name_separator))
+                        {
+                            return sax->parse_error(m_lexer.get_position(),
+                                                    m_lexer.get_token_string(),
+                                                    parse_error::create(101, m_lexer.get_position(),
+                                                            exception_message(token_type::name_separator, "object separator")));
+                        }
+
+                        // parse values
+                        get_token();
+                        continue;
+                    }
+
+                    // closing }
+                    if (JSON_LIKELY(last_token == token_type::end_object))
+                    {
+                        if (JSON_UNLIKELY(not sax->end_object()))
+                        {
+                            return false;
+                        }
+
+                        // We are done with this object. Before we can parse a
+                        // new value, we need to evaluate the new state first.
+                        // By setting skip_to_state_evaluation to false, we
+                        // are effectively jumping to the beginning of this if.
+                        assert(not states.empty());
+                        states.pop_back();
+                        skip_to_state_evaluation = true;
+                        continue;
+                    }
+                    else
+                    {
+                        return sax->parse_error(m_lexer.get_position(),
+                                                m_lexer.get_token_string(),
+                                                parse_error::create(101, m_lexer.get_position(),
+                                                        exception_message(token_type::end_object, "object")));
+                    }
+                }
+            }
+        }
+    }
+
+    /// get next token from lexer
+    token_type get_token()
+    {
+        return (last_token = m_lexer.scan());
+    }
+
+    std::string exception_message(const token_type expected, const std::string& context)
+    {
+        std::string error_msg = "syntax error ";
+
+        if (not context.empty())
+        {
+            error_msg += "while parsing " + context + " ";
+        }
+
+        error_msg += "- ";
+
+        if (last_token == token_type::parse_error)
+        {
+            error_msg += std::string(m_lexer.get_error_message()) + "; last read: '" +
+                         m_lexer.get_token_string() + "'";
+        }
+        else
+        {
+            error_msg += "unexpected " + std::string(lexer_t::token_type_name(last_token));
+        }
+
+        if (expected != token_type::uninitialized)
+        {
+            error_msg += "; expected " + std::string(lexer_t::token_type_name(expected));
+        }
+
+        return error_msg;
+    }
+
+  private:
+    /// callback function
+    const parser_callback_t callback = nullptr;
+    /// the type of the last read token
+    token_type last_token = token_type::uninitialized;
+    /// the lexer
+    lexer_t m_lexer;
+    /// whether to throw exceptions in case of errors
+    const bool allow_exceptions = true;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
+
+
+#include <cstddef> // ptrdiff_t
+#include <limits>  // numeric_limits
+
+namespace nlohmann
+{
+namespace detail
+{
+/*
+@brief an iterator for primitive JSON types
+
+This class models an iterator for primitive JSON types (boolean, number,
+string). It's only purpose is to allow the iterator/const_iterator classes
+to "iterate" over primitive values. Internally, the iterator is modeled by
+a `difference_type` variable. Value begin_value (`0`) models the begin,
+end_value (`1`) models past the end.
+*/
+class primitive_iterator_t
+{
+  private:
+    using difference_type = std::ptrdiff_t;
+    static constexpr difference_type begin_value = 0;
+    static constexpr difference_type end_value = begin_value + 1;
+
+    /// iterator as signed integer type
+    difference_type m_it = (std::numeric_limits<std::ptrdiff_t>::min)();
+
+  public:
+    constexpr difference_type get_value() const noexcept
+    {
+        return m_it;
+    }
+
+    /// set iterator to a defined beginning
+    void set_begin() noexcept
+    {
+        m_it = begin_value;
+    }
+
+    /// set iterator to a defined past the end
+    void set_end() noexcept
+    {
+        m_it = end_value;
+    }
+
+    /// return whether the iterator can be dereferenced
+    constexpr bool is_begin() const noexcept
+    {
+        return m_it == begin_value;
+    }
+
+    /// return whether the iterator is at end
+    constexpr bool is_end() const noexcept
+    {
+        return m_it == end_value;
+    }
+
+    friend constexpr bool operator==(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
+    {
+        return lhs.m_it == rhs.m_it;
+    }
+
+    friend constexpr bool operator<(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
+    {
+        return lhs.m_it < rhs.m_it;
+    }
+
+    primitive_iterator_t operator+(difference_type n) noexcept
+    {
+        auto result = *this;
+        result += n;
+        return result;
+    }
+
+    friend constexpr difference_type operator-(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
+    {
+        return lhs.m_it - rhs.m_it;
+    }
+
+    primitive_iterator_t& operator++() noexcept
+    {
+        ++m_it;
+        return *this;
+    }
+
+    primitive_iterator_t const operator++(int) noexcept
+    {
+        auto result = *this;
+        ++m_it;
+        return result;
+    }
+
+    primitive_iterator_t& operator--() noexcept
+    {
+        --m_it;
+        return *this;
+    }
+
+    primitive_iterator_t const operator--(int) noexcept
+    {
+        auto result = *this;
+        --m_it;
+        return result;
+    }
+
+    primitive_iterator_t& operator+=(difference_type n) noexcept
+    {
+        m_it += n;
+        return *this;
+    }
+
+    primitive_iterator_t& operator-=(difference_type n) noexcept
+    {
+        m_it -= n;
+        return *this;
+    }
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/iterators/internal_iterator.hpp>
+
+
+// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+/*!
+@brief an iterator value
+
+@note This structure could easily be a union, but MSVC currently does not allow
+unions members with complex constructors, see https://github.com/nlohmann/json/pull/105.
+*/
+template<typename BasicJsonType> struct internal_iterator
+{
+    /// iterator for JSON objects
+    typename BasicJsonType::object_t::iterator object_iterator {};
+    /// iterator for JSON arrays
+    typename BasicJsonType::array_t::iterator array_iterator {};
+    /// generic iterator for all other types
+    primitive_iterator_t primitive_iterator {};
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/iterators/iter_impl.hpp>
+
+
+#include <ciso646> // not
+#include <iterator> // iterator, random_access_iterator_tag, bidirectional_iterator_tag, advance, next
+#include <type_traits> // conditional, is_const, remove_const
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+// #include <nlohmann/detail/iterators/internal_iterator.hpp>
+
+// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+// forward declare, to be able to friend it later on
+template<typename IteratorType> class iteration_proxy;
+template<typename IteratorType> class iteration_proxy_value;
+
+/*!
+@brief a template for a bidirectional iterator for the @ref basic_json class
+This class implements a both iterators (iterator and const_iterator) for the
+@ref basic_json class.
+@note An iterator is called *initialized* when a pointer to a JSON value has
+      been set (e.g., by a constructor or a copy assignment). If the iterator is
+      default-constructed, it is *uninitialized* and most methods are undefined.
+      **The library uses assertions to detect calls on uninitialized iterators.**
+@requirement The class satisfies the following concept requirements:
+-
+[BidirectionalIterator](https://en.cppreference.com/w/cpp/named_req/BidirectionalIterator):
+  The iterator that can be moved can be moved in both directions (i.e.
+  incremented and decremented).
+@since version 1.0.0, simplified in version 2.0.9, change to bidirectional
+       iterators in version 3.0.0 (see https://github.com/nlohmann/json/issues/593)
+*/
+template<typename BasicJsonType>
+class iter_impl
+{
+    /// allow basic_json to access private members
+    friend iter_impl<typename std::conditional<std::is_const<BasicJsonType>::value, typename std::remove_const<BasicJsonType>::type, const BasicJsonType>::type>;
+    friend BasicJsonType;
+    friend iteration_proxy<iter_impl>;
+    friend iteration_proxy_value<iter_impl>;
+
+    using object_t = typename BasicJsonType::object_t;
+    using array_t = typename BasicJsonType::array_t;
+    // make sure BasicJsonType is basic_json or const basic_json
+    static_assert(is_basic_json<typename std::remove_const<BasicJsonType>::type>::value,
+                  "iter_impl only accepts (const) basic_json");
+
+  public:
+
+    /// The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17.
+    /// The C++ Standard has never required user-defined iterators to derive from std::iterator.
+    /// A user-defined iterator should provide publicly accessible typedefs named
+    /// iterator_category, value_type, difference_type, pointer, and reference.
+    /// Note that value_type is required to be non-const, even for constant iterators.
+    using iterator_category = std::bidirectional_iterator_tag;
+
+    /// the type of the values when the iterator is dereferenced
+    using value_type = typename BasicJsonType::value_type;
+    /// a type to represent differences between iterators
+    using difference_type = typename BasicJsonType::difference_type;
+    /// defines a pointer to the type iterated over (value_type)
+    using pointer = typename std::conditional<std::is_const<BasicJsonType>::value,
+          typename BasicJsonType::const_pointer,
+          typename BasicJsonType::pointer>::type;
+    /// defines a reference to the type iterated over (value_type)
+    using reference =
+        typename std::conditional<std::is_const<BasicJsonType>::value,
+        typename BasicJsonType::const_reference,
+        typename BasicJsonType::reference>::type;
+
+    /// default constructor
+    iter_impl() = default;
+
+    /*!
+    @brief constructor for a given JSON instance
+    @param[in] object  pointer to a JSON object for this iterator
+    @pre object != nullptr
+    @post The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    explicit iter_impl(pointer object) noexcept : m_object(object)
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                m_it.object_iterator = typename object_t::iterator();
+                break;
+            }
+
+            case value_t::array:
+            {
+                m_it.array_iterator = typename array_t::iterator();
+                break;
+            }
+
+            default:
+            {
+                m_it.primitive_iterator = primitive_iterator_t();
+                break;
+            }
+        }
+    }
+
+    /*!
+    @note The conventional copy constructor and copy assignment are implicitly
+          defined. Combined with the following converting constructor and
+          assignment, they support: (1) copy from iterator to iterator, (2)
+          copy from const iterator to const iterator, and (3) conversion from
+          iterator to const iterator. However conversion from const iterator
+          to iterator is not defined.
+    */
+
+    /*!
+    @brief converting constructor
+    @param[in] other  non-const iterator to copy from
+    @note It is not checked whether @a other is initialized.
+    */
+    iter_impl(const iter_impl<typename std::remove_const<BasicJsonType>::type>& other) noexcept
+        : m_object(other.m_object), m_it(other.m_it) {}
+
+    /*!
+    @brief converting assignment
+    @param[in,out] other  non-const iterator to copy from
+    @return const/non-const iterator
+    @note It is not checked whether @a other is initialized.
+    */
+    iter_impl& operator=(const iter_impl<typename std::remove_const<BasicJsonType>::type>& other) noexcept
+    {
+        m_object = other.m_object;
+        m_it = other.m_it;
+        return *this;
+    }
+
+  private:
+    /*!
+    @brief set the iterator to the first value
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    void set_begin() noexcept
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                m_it.object_iterator = m_object->m_value.object->begin();
+                break;
+            }
+
+            case value_t::array:
+            {
+                m_it.array_iterator = m_object->m_value.array->begin();
+                break;
+            }
+
+            case value_t::null:
+            {
+                // set to end so begin()==end() is true: null is empty
+                m_it.primitive_iterator.set_end();
+                break;
+            }
+
+            default:
+            {
+                m_it.primitive_iterator.set_begin();
+                break;
+            }
+        }
+    }
+
+    /*!
+    @brief set the iterator past the last value
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    void set_end() noexcept
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                m_it.object_iterator = m_object->m_value.object->end();
+                break;
+            }
+
+            case value_t::array:
+            {
+                m_it.array_iterator = m_object->m_value.array->end();
+                break;
+            }
+
+            default:
+            {
+                m_it.primitive_iterator.set_end();
+                break;
+            }
+        }
+    }
+
+  public:
+    /*!
+    @brief return a reference to the value pointed to by the iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    reference operator*() const
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                assert(m_it.object_iterator != m_object->m_value.object->end());
+                return m_it.object_iterator->second;
+            }
+
+            case value_t::array:
+            {
+                assert(m_it.array_iterator != m_object->m_value.array->end());
+                return *m_it.array_iterator;
+            }
+
+            case value_t::null:
+                JSON_THROW(invalid_iterator::create(214, "cannot get value"));
+
+            default:
+            {
+                if (JSON_LIKELY(m_it.primitive_iterator.is_begin()))
+                {
+                    return *m_object;
+                }
+
+                JSON_THROW(invalid_iterator::create(214, "cannot get value"));
+            }
+        }
+    }
+
+    /*!
+    @brief dereference the iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    pointer operator->() const
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                assert(m_it.object_iterator != m_object->m_value.object->end());
+                return &(m_it.object_iterator->second);
+            }
+
+            case value_t::array:
+            {
+                assert(m_it.array_iterator != m_object->m_value.array->end());
+                return &*m_it.array_iterator;
+            }
+
+            default:
+            {
+                if (JSON_LIKELY(m_it.primitive_iterator.is_begin()))
+                {
+                    return m_object;
+                }
+
+                JSON_THROW(invalid_iterator::create(214, "cannot get value"));
+            }
+        }
+    }
+
+    /*!
+    @brief post-increment (it++)
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl const operator++(int)
+    {
+        auto result = *this;
+        ++(*this);
+        return result;
+    }
+
+    /*!
+    @brief pre-increment (++it)
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl& operator++()
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                std::advance(m_it.object_iterator, 1);
+                break;
+            }
+
+            case value_t::array:
+            {
+                std::advance(m_it.array_iterator, 1);
+                break;
+            }
+
+            default:
+            {
+                ++m_it.primitive_iterator;
+                break;
+            }
+        }
+
+        return *this;
+    }
+
+    /*!
+    @brief post-decrement (it--)
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl const operator--(int)
+    {
+        auto result = *this;
+        --(*this);
+        return result;
+    }
+
+    /*!
+    @brief pre-decrement (--it)
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl& operator--()
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+            {
+                std::advance(m_it.object_iterator, -1);
+                break;
+            }
+
+            case value_t::array:
+            {
+                std::advance(m_it.array_iterator, -1);
+                break;
+            }
+
+            default:
+            {
+                --m_it.primitive_iterator;
+                break;
+            }
+        }
+
+        return *this;
+    }
+
+    /*!
+    @brief  comparison: equal
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    bool operator==(const iter_impl& other) const
+    {
+        // if objects are not the same, the comparison is undefined
+        if (JSON_UNLIKELY(m_object != other.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers"));
+        }
+
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+                return (m_it.object_iterator == other.m_it.object_iterator);
+
+            case value_t::array:
+                return (m_it.array_iterator == other.m_it.array_iterator);
+
+            default:
+                return (m_it.primitive_iterator == other.m_it.primitive_iterator);
+        }
+    }
+
+    /*!
+    @brief  comparison: not equal
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    bool operator!=(const iter_impl& other) const
+    {
+        return not operator==(other);
+    }
+
+    /*!
+    @brief  comparison: smaller
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    bool operator<(const iter_impl& other) const
+    {
+        // if objects are not the same, the comparison is undefined
+        if (JSON_UNLIKELY(m_object != other.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers"));
+        }
+
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+                JSON_THROW(invalid_iterator::create(213, "cannot compare order of object iterators"));
+
+            case value_t::array:
+                return (m_it.array_iterator < other.m_it.array_iterator);
+
+            default:
+                return (m_it.primitive_iterator < other.m_it.primitive_iterator);
+        }
+    }
+
+    /*!
+    @brief  comparison: less than or equal
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    bool operator<=(const iter_impl& other) const
+    {
+        return not other.operator < (*this);
+    }
+
+    /*!
+    @brief  comparison: greater than
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    bool operator>(const iter_impl& other) const
+    {
+        return not operator<=(other);
+    }
+
+    /*!
+    @brief  comparison: greater than or equal
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    bool operator>=(const iter_impl& other) const
+    {
+        return not operator<(other);
+    }
+
+    /*!
+    @brief  add to iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl& operator+=(difference_type i)
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+                JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators"));
+
+            case value_t::array:
+            {
+                std::advance(m_it.array_iterator, i);
+                break;
+            }
+
+            default:
+            {
+                m_it.primitive_iterator += i;
+                break;
+            }
+        }
+
+        return *this;
+    }
+
+    /*!
+    @brief  subtract from iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl& operator-=(difference_type i)
+    {
+        return operator+=(-i);
+    }
+
+    /*!
+    @brief  add to iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl operator+(difference_type i) const
+    {
+        auto result = *this;
+        result += i;
+        return result;
+    }
+
+    /*!
+    @brief  addition of distance and iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    friend iter_impl operator+(difference_type i, const iter_impl& it)
+    {
+        auto result = it;
+        result += i;
+        return result;
+    }
+
+    /*!
+    @brief  subtract from iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    iter_impl operator-(difference_type i) const
+    {
+        auto result = *this;
+        result -= i;
+        return result;
+    }
+
+    /*!
+    @brief  return difference
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    difference_type operator-(const iter_impl& other) const
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+                JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators"));
+
+            case value_t::array:
+                return m_it.array_iterator - other.m_it.array_iterator;
+
+            default:
+                return m_it.primitive_iterator - other.m_it.primitive_iterator;
+        }
+    }
+
+    /*!
+    @brief  access to successor
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    reference operator[](difference_type n) const
+    {
+        assert(m_object != nullptr);
+
+        switch (m_object->m_type)
+        {
+            case value_t::object:
+                JSON_THROW(invalid_iterator::create(208, "cannot use operator[] for object iterators"));
+
+            case value_t::array:
+                return *std::next(m_it.array_iterator, n);
+
+            case value_t::null:
+                JSON_THROW(invalid_iterator::create(214, "cannot get value"));
+
+            default:
+            {
+                if (JSON_LIKELY(m_it.primitive_iterator.get_value() == -n))
+                {
+                    return *m_object;
+                }
+
+                JSON_THROW(invalid_iterator::create(214, "cannot get value"));
+            }
+        }
+    }
+
+    /*!
+    @brief  return the key of an object iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    const typename object_t::key_type& key() const
+    {
+        assert(m_object != nullptr);
+
+        if (JSON_LIKELY(m_object->is_object()))
+        {
+            return m_it.object_iterator->first;
+        }
+
+        JSON_THROW(invalid_iterator::create(207, "cannot use key() for non-object iterators"));
+    }
+
+    /*!
+    @brief  return the value of an iterator
+    @pre The iterator is initialized; i.e. `m_object != nullptr`.
+    */
+    reference value() const
+    {
+        return operator*();
+    }
+
+  private:
+    /// associated JSON instance
+    pointer m_object = nullptr;
+    /// the actual iterator of the associated instance
+    internal_iterator<typename std::remove_const<BasicJsonType>::type> m_it;
+};
+}  // namespace detail
+} // namespace nlohmann
+// #include <nlohmann/detail/iterators/iteration_proxy.hpp>
+
+// #include <nlohmann/detail/iterators/json_reverse_iterator.hpp>
+
+
+#include <cstddef> // ptrdiff_t
+#include <iterator> // reverse_iterator
+#include <utility> // declval
+
+namespace nlohmann
+{
+namespace detail
+{
+//////////////////////
+// reverse_iterator //
+//////////////////////
+
+/*!
+@brief a template for a reverse iterator class
+
+@tparam Base the base iterator type to reverse. Valid types are @ref
+iterator (to create @ref reverse_iterator) and @ref const_iterator (to
+create @ref const_reverse_iterator).
+
+@requirement The class satisfies the following concept requirements:
+-
+[BidirectionalIterator](https://en.cppreference.com/w/cpp/named_req/BidirectionalIterator):
+  The iterator that can be moved can be moved in both directions (i.e.
+  incremented and decremented).
+- [OutputIterator](https://en.cppreference.com/w/cpp/named_req/OutputIterator):
+  It is possible to write to the pointed-to element (only if @a Base is
+  @ref iterator).
+
+@since version 1.0.0
+*/
+template<typename Base>
+class json_reverse_iterator : public std::reverse_iterator<Base>
+{
+  public:
+    using difference_type = std::ptrdiff_t;
+    /// shortcut to the reverse iterator adapter
+    using base_iterator = std::reverse_iterator<Base>;
+    /// the reference type for the pointed-to element
+    using reference = typename Base::reference;
+
+    /// create reverse iterator from iterator
+    explicit json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
+        : base_iterator(it) {}
+
+    /// create reverse iterator from base class
+    explicit json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {}
+
+    /// post-increment (it++)
+    json_reverse_iterator const operator++(int)
+    {
+        return static_cast<json_reverse_iterator>(base_iterator::operator++(1));
+    }
+
+    /// pre-increment (++it)
+    json_reverse_iterator& operator++()
+    {
+        return static_cast<json_reverse_iterator&>(base_iterator::operator++());
+    }
+
+    /// post-decrement (it--)
+    json_reverse_iterator const operator--(int)
+    {
+        return static_cast<json_reverse_iterator>(base_iterator::operator--(1));
+    }
+
+    /// pre-decrement (--it)
+    json_reverse_iterator& operator--()
+    {
+        return static_cast<json_reverse_iterator&>(base_iterator::operator--());
+    }
+
+    /// add to iterator
+    json_reverse_iterator& operator+=(difference_type i)
+    {
+        return static_cast<json_reverse_iterator&>(base_iterator::operator+=(i));
+    }
+
+    /// add to iterator
+    json_reverse_iterator operator+(difference_type i) const
+    {
+        return static_cast<json_reverse_iterator>(base_iterator::operator+(i));
+    }
+
+    /// subtract from iterator
+    json_reverse_iterator operator-(difference_type i) const
+    {
+        return static_cast<json_reverse_iterator>(base_iterator::operator-(i));
+    }
+
+    /// return difference
+    difference_type operator-(const json_reverse_iterator& other) const
+    {
+        return base_iterator(*this) - base_iterator(other);
+    }
+
+    /// access to successor
+    reference operator[](difference_type n) const
+    {
+        return *(this->operator+(n));
+    }
+
+    /// return the key of an object iterator
+    auto key() const -> decltype(std::declval<Base>().key())
+    {
+        auto it = --this->base();
+        return it.key();
+    }
+
+    /// return the value of an iterator
+    reference value() const
+    {
+        auto it = --this->base();
+        return it.operator * ();
+    }
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/output/output_adapters.hpp>
+
+
+#include <algorithm> // copy
+#include <cstddef> // size_t
+#include <ios> // streamsize
+#include <iterator> // back_inserter
+#include <memory> // shared_ptr, make_shared
+#include <ostream> // basic_ostream
+#include <string> // basic_string
+#include <vector> // vector
+
+namespace nlohmann
+{
+namespace detail
+{
+/// abstract output adapter interface
+template<typename CharType> struct output_adapter_protocol
+{
+    virtual void write_character(CharType c) = 0;
+    virtual void write_characters(const CharType* s, std::size_t length) = 0;
+    virtual ~output_adapter_protocol() = default;
+};
+
+/// a type to simplify interfaces
+template<typename CharType>
+using output_adapter_t = std::shared_ptr<output_adapter_protocol<CharType>>;
+
+/// output adapter for byte vectors
+template<typename CharType>
+class output_vector_adapter : public output_adapter_protocol<CharType>
+{
+  public:
+    explicit output_vector_adapter(std::vector<CharType>& vec) noexcept
+        : v(vec)
+    {}
+
+    void write_character(CharType c) override
+    {
+        v.push_back(c);
+    }
+
+    void write_characters(const CharType* s, std::size_t length) override
+    {
+        std::copy(s, s + length, std::back_inserter(v));
+    }
+
+  private:
+    std::vector<CharType>& v;
+};
+
+/// output adapter for output streams
+template<typename CharType>
+class output_stream_adapter : public output_adapter_protocol<CharType>
+{
+  public:
+    explicit output_stream_adapter(std::basic_ostream<CharType>& s) noexcept
+        : stream(s)
+    {}
+
+    void write_character(CharType c) override
+    {
+        stream.put(c);
+    }
+
+    void write_characters(const CharType* s, std::size_t length) override
+    {
+        stream.write(s, static_cast<std::streamsize>(length));
+    }
+
+  private:
+    std::basic_ostream<CharType>& stream;
+};
+
+/// output adapter for basic_string
+template<typename CharType, typename StringType = std::basic_string<CharType>>
+class output_string_adapter : public output_adapter_protocol<CharType>
+{
+  public:
+    explicit output_string_adapter(StringType& s) noexcept
+        : str(s)
+    {}
+
+    void write_character(CharType c) override
+    {
+        str.push_back(c);
+    }
+
+    void write_characters(const CharType* s, std::size_t length) override
+    {
+        str.append(s, length);
+    }
+
+  private:
+    StringType& str;
+};
+
+template<typename CharType, typename StringType = std::basic_string<CharType>>
+class output_adapter
+{
+  public:
+    output_adapter(std::vector<CharType>& vec)
+        : oa(std::make_shared<output_vector_adapter<CharType>>(vec)) {}
+
+    output_adapter(std::basic_ostream<CharType>& s)
+        : oa(std::make_shared<output_stream_adapter<CharType>>(s)) {}
+
+    output_adapter(StringType& s)
+        : oa(std::make_shared<output_string_adapter<CharType, StringType>>(s)) {}
+
+    operator output_adapter_t<CharType>()
+    {
+        return oa;
+    }
+
+  private:
+    output_adapter_t<CharType> oa = nullptr;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/input/binary_reader.hpp>
+
+
+#include <algorithm> // generate_n
+#include <array> // array
+#include <cassert> // assert
+#include <cmath> // ldexp
+#include <cstddef> // size_t
+#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t
+#include <cstdio> // snprintf
+#include <cstring> // memcpy
+#include <iterator> // back_inserter
+#include <limits> // numeric_limits
+#include <string> // char_traits, string
+#include <utility> // make_pair, move
+
+// #include <nlohmann/detail/input/input_adapters.hpp>
+
+// #include <nlohmann/detail/input/json_sax.hpp>
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/meta/is_sax.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+///////////////////
+// binary reader //
+///////////////////
+
+/*!
+@brief deserialization of CBOR, MessagePack, and UBJSON values
+*/
+template<typename BasicJsonType, typename SAX = json_sax_dom_parser<BasicJsonType>>
+class binary_reader
+{
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using string_t = typename BasicJsonType::string_t;
+    using json_sax_t = SAX;
+
+  public:
+    /*!
+    @brief create a binary reader
+
+    @param[in] adapter  input adapter to read from
+    */
+    explicit binary_reader(input_adapter_t adapter) : ia(std::move(adapter))
+    {
+        (void)detail::is_sax_static_asserts<SAX, BasicJsonType> {};
+        assert(ia);
+    }
+
+    /*!
+    @param[in] format  the binary format to parse
+    @param[in] sax_    a SAX event processor
+    @param[in] strict  whether to expect the input to be consumed completed
+
+    @return
+    */
+    bool sax_parse(const input_format_t format,
+                   json_sax_t* sax_,
+                   const bool strict = true)
+    {
+        sax = sax_;
+        bool result = false;
+
+        switch (format)
+        {
+            case input_format_t::bson:
+                result = parse_bson_internal();
+                break;
+
+            case input_format_t::cbor:
+                result = parse_cbor_internal();
+                break;
+
+            case input_format_t::msgpack:
+                result = parse_msgpack_internal();
+                break;
+
+            case input_format_t::ubjson:
+                result = parse_ubjson_internal();
+                break;
+
+            // LCOV_EXCL_START
+            default:
+                assert(false);
+                // LCOV_EXCL_STOP
+        }
+
+        // strict mode: next byte must be EOF
+        if (result and strict)
+        {
+            if (format == input_format_t::ubjson)
+            {
+                get_ignore_noop();
+            }
+            else
+            {
+                get();
+            }
+
+            if (JSON_UNLIKELY(current != std::char_traits<char>::eof()))
+            {
+                return sax->parse_error(chars_read, get_token_string(),
+                                        parse_error::create(110, chars_read, exception_message(format, "expected end of input; last byte: 0x" + get_token_string(), "value")));
+            }
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief determine system byte order
+
+    @return true if and only if system's byte order is little endian
+
+    @note from http://stackoverflow.com/a/1001328/266378
+    */
+    static constexpr bool little_endianess(int num = 1) noexcept
+    {
+        return (*reinterpret_cast<char*>(&num) == 1);
+    }
+
+  private:
+    //////////
+    // BSON //
+    //////////
+
+    /*!
+    @brief Reads in a BSON-object and passes it to the SAX-parser.
+    @return whether a valid BSON-value was passed to the SAX parser
+    */
+    bool parse_bson_internal()
+    {
+        std::int32_t document_size;
+        get_number<std::int32_t, true>(input_format_t::bson, document_size);
+
+        if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
+        {
+            return false;
+        }
+
+        if (JSON_UNLIKELY(not parse_bson_element_list(/*is_array*/false)))
+        {
+            return false;
+        }
+
+        return sax->end_object();
+    }
+
+    /*!
+    @brief Parses a C-style string from the BSON input.
+    @param[in, out] result  A reference to the string variable where the read
+                            string is to be stored.
+    @return `true` if the \x00-byte indicating the end of the string was
+             encountered before the EOF; false` indicates an unexpected EOF.
+    */
+    bool get_bson_cstr(string_t& result)
+    {
+        auto out = std::back_inserter(result);
+        while (true)
+        {
+            get();
+            if (JSON_UNLIKELY(not unexpect_eof(input_format_t::bson, "cstring")))
+            {
+                return false;
+            }
+            if (current == 0x00)
+            {
+                return true;
+            }
+            *out++ = static_cast<char>(current);
+        }
+
+        return true;
+    }
+
+    /*!
+    @brief Parses a zero-terminated string of length @a len from the BSON
+           input.
+    @param[in] len  The length (including the zero-byte at the end) of the
+                    string to be read.
+    @param[in, out] result  A reference to the string variable where the read
+                            string is to be stored.
+    @tparam NumberType The type of the length @a len
+    @pre len >= 1
+    @return `true` if the string was successfully parsed
+    */
+    template<typename NumberType>
+    bool get_bson_string(const NumberType len, string_t& result)
+    {
+        if (JSON_UNLIKELY(len < 1))
+        {
+            auto last_token = get_token_string();
+            return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::bson, "string length must be at least 1, is " + std::to_string(len), "string")));
+        }
+
+        return get_string(input_format_t::bson, len - static_cast<NumberType>(1), result) and get() != std::char_traits<char>::eof();
+    }
+
+    /*!
+    @brief Read a BSON document element of the given @a element_type.
+    @param[in] element_type The BSON element type, c.f. http://bsonspec.org/spec.html
+    @param[in] element_type_parse_position The position in the input stream,
+               where the `element_type` was read.
+    @warning Not all BSON element types are supported yet. An unsupported
+             @a element_type will give rise to a parse_error.114:
+             Unsupported BSON record type 0x...
+    @return whether a valid BSON-object/array was passed to the SAX parser
+    */
+    bool parse_bson_element_internal(const int element_type,
+                                     const std::size_t element_type_parse_position)
+    {
+        switch (element_type)
+        {
+            case 0x01: // double
+            {
+                double number;
+                return get_number<double, true>(input_format_t::bson, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            case 0x02: // string
+            {
+                std::int32_t len;
+                string_t value;
+                return get_number<std::int32_t, true>(input_format_t::bson, len) and get_bson_string(len, value) and sax->string(value);
+            }
+
+            case 0x03: // object
+            {
+                return parse_bson_internal();
+            }
+
+            case 0x04: // array
+            {
+                return parse_bson_array();
+            }
+
+            case 0x08: // boolean
+            {
+                return sax->boolean(get() != 0);
+            }
+
+            case 0x0A: // null
+            {
+                return sax->null();
+            }
+
+            case 0x10: // int32
+            {
+                std::int32_t value;
+                return get_number<std::int32_t, true>(input_format_t::bson, value) and sax->number_integer(value);
+            }
+
+            case 0x12: // int64
+            {
+                std::int64_t value;
+                return get_number<std::int64_t, true>(input_format_t::bson, value) and sax->number_integer(value);
+            }
+
+            default: // anything else not supported (yet)
+            {
+                char cr[3];
+                (std::snprintf)(cr, sizeof(cr), "%.2hhX", static_cast<unsigned char>(element_type));
+                return sax->parse_error(element_type_parse_position, std::string(cr), parse_error::create(114, element_type_parse_position, "Unsupported BSON record type 0x" + std::string(cr)));
+            }
+        }
+    }
+
+    /*!
+    @brief Read a BSON element list (as specified in the BSON-spec)
+
+    The same binary layout is used for objects and arrays, hence it must be
+    indicated with the argument @a is_array which one is expected
+    (true --> array, false --> object).
+
+    @param[in] is_array Determines if the element list being read is to be
+                        treated as an object (@a is_array == false), or as an
+                        array (@a is_array == true).
+    @return whether a valid BSON-object/array was passed to the SAX parser
+    */
+    bool parse_bson_element_list(const bool is_array)
+    {
+        string_t key;
+        while (int element_type = get())
+        {
+            if (JSON_UNLIKELY(not unexpect_eof(input_format_t::bson, "element list")))
+            {
+                return false;
+            }
+
+            const std::size_t element_type_parse_position = chars_read;
+            if (JSON_UNLIKELY(not get_bson_cstr(key)))
+            {
+                return false;
+            }
+
+            if (not is_array)
+            {
+                if (not sax->key(key))
+                {
+                    return false;
+                }
+            }
+
+            if (JSON_UNLIKELY(not parse_bson_element_internal(element_type, element_type_parse_position)))
+            {
+                return false;
+            }
+
+            // get_bson_cstr only appends
+            key.clear();
+        }
+
+        return true;
+    }
+
+    /*!
+    @brief Reads an array from the BSON input and passes it to the SAX-parser.
+    @return whether a valid BSON-array was passed to the SAX parser
+    */
+    bool parse_bson_array()
+    {
+        std::int32_t document_size;
+        get_number<std::int32_t, true>(input_format_t::bson, document_size);
+
+        if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
+        {
+            return false;
+        }
+
+        if (JSON_UNLIKELY(not parse_bson_element_list(/*is_array*/true)))
+        {
+            return false;
+        }
+
+        return sax->end_array();
+    }
+
+    //////////
+    // CBOR //
+    //////////
+
+    /*!
+    @param[in] get_char  whether a new character should be retrieved from the
+                         input (true, default) or whether the last read
+                         character should be considered instead
+
+    @return whether a valid CBOR value was passed to the SAX parser
+    */
+    bool parse_cbor_internal(const bool get_char = true)
+    {
+        switch (get_char ? get() : current)
+        {
+            // EOF
+            case std::char_traits<char>::eof():
+                return unexpect_eof(input_format_t::cbor, "value");
+
+            // Integer 0x00..0x17 (0..23)
+            case 0x00:
+            case 0x01:
+            case 0x02:
+            case 0x03:
+            case 0x04:
+            case 0x05:
+            case 0x06:
+            case 0x07:
+            case 0x08:
+            case 0x09:
+            case 0x0A:
+            case 0x0B:
+            case 0x0C:
+            case 0x0D:
+            case 0x0E:
+            case 0x0F:
+            case 0x10:
+            case 0x11:
+            case 0x12:
+            case 0x13:
+            case 0x14:
+            case 0x15:
+            case 0x16:
+            case 0x17:
+                return sax->number_unsigned(static_cast<number_unsigned_t>(current));
+
+            case 0x18: // Unsigned integer (one-byte uint8_t follows)
+            {
+                uint8_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+            }
+
+            case 0x19: // Unsigned integer (two-byte uint16_t follows)
+            {
+                uint16_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+            }
+
+            case 0x1A: // Unsigned integer (four-byte uint32_t follows)
+            {
+                uint32_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+            }
+
+            case 0x1B: // Unsigned integer (eight-byte uint64_t follows)
+            {
+                uint64_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_unsigned(number);
+            }
+
+            // Negative integer -1-0x00..-1-0x17 (-1..-24)
+            case 0x20:
+            case 0x21:
+            case 0x22:
+            case 0x23:
+            case 0x24:
+            case 0x25:
+            case 0x26:
+            case 0x27:
+            case 0x28:
+            case 0x29:
+            case 0x2A:
+            case 0x2B:
+            case 0x2C:
+            case 0x2D:
+            case 0x2E:
+            case 0x2F:
+            case 0x30:
+            case 0x31:
+            case 0x32:
+            case 0x33:
+            case 0x34:
+            case 0x35:
+            case 0x36:
+            case 0x37:
+                return sax->number_integer(static_cast<int8_t>(0x20 - 1 - current));
+
+            case 0x38: // Negative integer (one-byte uint8_t follows)
+            {
+                uint8_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
+            }
+
+            case 0x39: // Negative integer -1-n (two-byte uint16_t follows)
+            {
+                uint16_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
+            }
+
+            case 0x3A: // Negative integer -1-n (four-byte uint32_t follows)
+            {
+                uint32_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1) - number);
+            }
+
+            case 0x3B: // Negative integer -1-n (eight-byte uint64_t follows)
+            {
+                uint64_t number;
+                return get_number(input_format_t::cbor, number) and sax->number_integer(static_cast<number_integer_t>(-1)
+                        - static_cast<number_integer_t>(number));
+            }
+
+            // UTF-8 string (0x00..0x17 bytes follow)
+            case 0x60:
+            case 0x61:
+            case 0x62:
+            case 0x63:
+            case 0x64:
+            case 0x65:
+            case 0x66:
+            case 0x67:
+            case 0x68:
+            case 0x69:
+            case 0x6A:
+            case 0x6B:
+            case 0x6C:
+            case 0x6D:
+            case 0x6E:
+            case 0x6F:
+            case 0x70:
+            case 0x71:
+            case 0x72:
+            case 0x73:
+            case 0x74:
+            case 0x75:
+            case 0x76:
+            case 0x77:
+            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
+            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
+            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
+            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
+            case 0x7F: // UTF-8 string (indefinite length)
+            {
+                string_t s;
+                return get_cbor_string(s) and sax->string(s);
+            }
+
+            // array (0x00..0x17 data items follow)
+            case 0x80:
+            case 0x81:
+            case 0x82:
+            case 0x83:
+            case 0x84:
+            case 0x85:
+            case 0x86:
+            case 0x87:
+            case 0x88:
+            case 0x89:
+            case 0x8A:
+            case 0x8B:
+            case 0x8C:
+            case 0x8D:
+            case 0x8E:
+            case 0x8F:
+            case 0x90:
+            case 0x91:
+            case 0x92:
+            case 0x93:
+            case 0x94:
+            case 0x95:
+            case 0x96:
+            case 0x97:
+                return get_cbor_array(static_cast<std::size_t>(current & 0x1F));
+
+            case 0x98: // array (one-byte uint8_t for n follows)
+            {
+                uint8_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+            }
+
+            case 0x99: // array (two-byte uint16_t for n follow)
+            {
+                uint16_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+            }
+
+            case 0x9A: // array (four-byte uint32_t for n follow)
+            {
+                uint32_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+            }
+
+            case 0x9B: // array (eight-byte uint64_t for n follow)
+            {
+                uint64_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_array(static_cast<std::size_t>(len));
+            }
+
+            case 0x9F: // array (indefinite length)
+                return get_cbor_array(std::size_t(-1));
+
+            // map (0x00..0x17 pairs of data items follow)
+            case 0xA0:
+            case 0xA1:
+            case 0xA2:
+            case 0xA3:
+            case 0xA4:
+            case 0xA5:
+            case 0xA6:
+            case 0xA7:
+            case 0xA8:
+            case 0xA9:
+            case 0xAA:
+            case 0xAB:
+            case 0xAC:
+            case 0xAD:
+            case 0xAE:
+            case 0xAF:
+            case 0xB0:
+            case 0xB1:
+            case 0xB2:
+            case 0xB3:
+            case 0xB4:
+            case 0xB5:
+            case 0xB6:
+            case 0xB7:
+                return get_cbor_object(static_cast<std::size_t>(current & 0x1F));
+
+            case 0xB8: // map (one-byte uint8_t for n follows)
+            {
+                uint8_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+            }
+
+            case 0xB9: // map (two-byte uint16_t for n follow)
+            {
+                uint16_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+            }
+
+            case 0xBA: // map (four-byte uint32_t for n follow)
+            {
+                uint32_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+            }
+
+            case 0xBB: // map (eight-byte uint64_t for n follow)
+            {
+                uint64_t len;
+                return get_number(input_format_t::cbor, len) and get_cbor_object(static_cast<std::size_t>(len));
+            }
+
+            case 0xBF: // map (indefinite length)
+                return get_cbor_object(std::size_t(-1));
+
+            case 0xF4: // false
+                return sax->boolean(false);
+
+            case 0xF5: // true
+                return sax->boolean(true);
+
+            case 0xF6: // null
+                return sax->null();
+
+            case 0xF9: // Half-Precision Float (two-byte IEEE 754)
+            {
+                const int byte1_raw = get();
+                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "number")))
+                {
+                    return false;
+                }
+                const int byte2_raw = get();
+                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "number")))
+                {
+                    return false;
+                }
+
+                const auto byte1 = static_cast<unsigned char>(byte1_raw);
+                const auto byte2 = static_cast<unsigned char>(byte2_raw);
+
+                // code from RFC 7049, Appendix D, Figure 3:
+                // As half-precision floating-point numbers were only added
+                // to IEEE 754 in 2008, today's programming platforms often
+                // still only have limited support for them. It is very
+                // easy to include at least decoding support for them even
+                // without such support. An example of a small decoder for
+                // half-precision floating-point numbers in the C language
+                // is shown in Fig. 3.
+                const int half = (byte1 << 8) + byte2;
+                const double val = [&half]
+                {
+                    const int exp = (half >> 10) & 0x1F;
+                    const int mant = half & 0x3FF;
+                    assert(0 <= exp and exp <= 32);
+                    assert(0 <= mant and mant <= 1024);
+                    switch (exp)
+                    {
+                        case 0:
+                            return std::ldexp(mant, -24);
+                        case 31:
+                            return (mant == 0)
+                            ? std::numeric_limits<double>::infinity()
+                            : std::numeric_limits<double>::quiet_NaN();
+                        default:
+                            return std::ldexp(mant + 1024, exp - 25);
+                    }
+                }();
+                return sax->number_float((half & 0x8000) != 0
+                                         ? static_cast<number_float_t>(-val)
+                                         : static_cast<number_float_t>(val), "");
+            }
+
+            case 0xFA: // Single-Precision Float (four-byte IEEE 754)
+            {
+                float number;
+                return get_number(input_format_t::cbor, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
+            {
+                double number;
+                return get_number(input_format_t::cbor, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            default: // anything else (0xFF is handled inside the other types)
+            {
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::cbor, "invalid byte: 0x" + last_token, "value")));
+            }
+        }
+    }
+
+    /*!
+    @brief reads a CBOR string
+
+    This function first reads starting bytes to determine the expected
+    string length and then copies this number of bytes into a string.
+    Additionally, CBOR's strings with indefinite lengths are supported.
+
+    @param[out] result  created string
+
+    @return whether string creation completed
+    */
+    bool get_cbor_string(string_t& result)
+    {
+        if (JSON_UNLIKELY(not unexpect_eof(input_format_t::cbor, "string")))
+        {
+            return false;
+        }
+
+        switch (current)
+        {
+            // UTF-8 string (0x00..0x17 bytes follow)
+            case 0x60:
+            case 0x61:
+            case 0x62:
+            case 0x63:
+            case 0x64:
+            case 0x65:
+            case 0x66:
+            case 0x67:
+            case 0x68:
+            case 0x69:
+            case 0x6A:
+            case 0x6B:
+            case 0x6C:
+            case 0x6D:
+            case 0x6E:
+            case 0x6F:
+            case 0x70:
+            case 0x71:
+            case 0x72:
+            case 0x73:
+            case 0x74:
+            case 0x75:
+            case 0x76:
+            case 0x77:
+            {
+                return get_string(input_format_t::cbor, current & 0x1F, result);
+            }
+
+            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
+            {
+                uint8_t len;
+                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+            }
+
+            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
+            {
+                uint16_t len;
+                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+            }
+
+            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
+            {
+                uint32_t len;
+                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+            }
+
+            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
+            {
+                uint64_t len;
+                return get_number(input_format_t::cbor, len) and get_string(input_format_t::cbor, len, result);
+            }
+
+            case 0x7F: // UTF-8 string (indefinite length)
+            {
+                while (get() != 0xFF)
+                {
+                    string_t chunk;
+                    if (not get_cbor_string(chunk))
+                    {
+                        return false;
+                    }
+                    result.append(chunk);
+                }
+                return true;
+            }
+
+            default:
+            {
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::cbor, "expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x" + last_token, "string")));
+            }
+        }
+    }
+
+    /*!
+    @param[in] len  the length of the array or std::size_t(-1) for an
+                    array of indefinite size
+    @return whether array creation completed
+    */
+    bool get_cbor_array(const std::size_t len)
+    {
+        if (JSON_UNLIKELY(not sax->start_array(len)))
+        {
+            return false;
+        }
+
+        if (len != std::size_t(-1))
+        {
+            for (std::size_t i = 0; i < len; ++i)
+            {
+                if (JSON_UNLIKELY(not parse_cbor_internal()))
+                {
+                    return false;
+                }
+            }
+        }
+        else
+        {
+            while (get() != 0xFF)
+            {
+                if (JSON_UNLIKELY(not parse_cbor_internal(false)))
+                {
+                    return false;
+                }
+            }
+        }
+
+        return sax->end_array();
+    }
+
+    /*!
+    @param[in] len  the length of the object or std::size_t(-1) for an
+                    object of indefinite size
+    @return whether object creation completed
+    */
+    bool get_cbor_object(const std::size_t len)
+    {
+        if (not JSON_UNLIKELY(sax->start_object(len)))
+        {
+            return false;
+        }
+
+        string_t key;
+        if (len != std::size_t(-1))
+        {
+            for (std::size_t i = 0; i < len; ++i)
+            {
+                get();
+                if (JSON_UNLIKELY(not get_cbor_string(key) or not sax->key(key)))
+                {
+                    return false;
+                }
+
+                if (JSON_UNLIKELY(not parse_cbor_internal()))
+                {
+                    return false;
+                }
+                key.clear();
+            }
+        }
+        else
+        {
+            while (get() != 0xFF)
+            {
+                if (JSON_UNLIKELY(not get_cbor_string(key) or not sax->key(key)))
+                {
+                    return false;
+                }
+
+                if (JSON_UNLIKELY(not parse_cbor_internal()))
+                {
+                    return false;
+                }
+                key.clear();
+            }
+        }
+
+        return sax->end_object();
+    }
+
+    /////////////
+    // MsgPack //
+    /////////////
+
+    /*!
+    @return whether a valid MessagePack value was passed to the SAX parser
+    */
+    bool parse_msgpack_internal()
+    {
+        switch (get())
+        {
+            // EOF
+            case std::char_traits<char>::eof():
+                return unexpect_eof(input_format_t::msgpack, "value");
+
+            // positive fixint
+            case 0x00:
+            case 0x01:
+            case 0x02:
+            case 0x03:
+            case 0x04:
+            case 0x05:
+            case 0x06:
+            case 0x07:
+            case 0x08:
+            case 0x09:
+            case 0x0A:
+            case 0x0B:
+            case 0x0C:
+            case 0x0D:
+            case 0x0E:
+            case 0x0F:
+            case 0x10:
+            case 0x11:
+            case 0x12:
+            case 0x13:
+            case 0x14:
+            case 0x15:
+            case 0x16:
+            case 0x17:
+            case 0x18:
+            case 0x19:
+            case 0x1A:
+            case 0x1B:
+            case 0x1C:
+            case 0x1D:
+            case 0x1E:
+            case 0x1F:
+            case 0x20:
+            case 0x21:
+            case 0x22:
+            case 0x23:
+            case 0x24:
+            case 0x25:
+            case 0x26:
+            case 0x27:
+            case 0x28:
+            case 0x29:
+            case 0x2A:
+            case 0x2B:
+            case 0x2C:
+            case 0x2D:
+            case 0x2E:
+            case 0x2F:
+            case 0x30:
+            case 0x31:
+            case 0x32:
+            case 0x33:
+            case 0x34:
+            case 0x35:
+            case 0x36:
+            case 0x37:
+            case 0x38:
+            case 0x39:
+            case 0x3A:
+            case 0x3B:
+            case 0x3C:
+            case 0x3D:
+            case 0x3E:
+            case 0x3F:
+            case 0x40:
+            case 0x41:
+            case 0x42:
+            case 0x43:
+            case 0x44:
+            case 0x45:
+            case 0x46:
+            case 0x47:
+            case 0x48:
+            case 0x49:
+            case 0x4A:
+            case 0x4B:
+            case 0x4C:
+            case 0x4D:
+            case 0x4E:
+            case 0x4F:
+            case 0x50:
+            case 0x51:
+            case 0x52:
+            case 0x53:
+            case 0x54:
+            case 0x55:
+            case 0x56:
+            case 0x57:
+            case 0x58:
+            case 0x59:
+            case 0x5A:
+            case 0x5B:
+            case 0x5C:
+            case 0x5D:
+            case 0x5E:
+            case 0x5F:
+            case 0x60:
+            case 0x61:
+            case 0x62:
+            case 0x63:
+            case 0x64:
+            case 0x65:
+            case 0x66:
+            case 0x67:
+            case 0x68:
+            case 0x69:
+            case 0x6A:
+            case 0x6B:
+            case 0x6C:
+            case 0x6D:
+            case 0x6E:
+            case 0x6F:
+            case 0x70:
+            case 0x71:
+            case 0x72:
+            case 0x73:
+            case 0x74:
+            case 0x75:
+            case 0x76:
+            case 0x77:
+            case 0x78:
+            case 0x79:
+            case 0x7A:
+            case 0x7B:
+            case 0x7C:
+            case 0x7D:
+            case 0x7E:
+            case 0x7F:
+                return sax->number_unsigned(static_cast<number_unsigned_t>(current));
+
+            // fixmap
+            case 0x80:
+            case 0x81:
+            case 0x82:
+            case 0x83:
+            case 0x84:
+            case 0x85:
+            case 0x86:
+            case 0x87:
+            case 0x88:
+            case 0x89:
+            case 0x8A:
+            case 0x8B:
+            case 0x8C:
+            case 0x8D:
+            case 0x8E:
+            case 0x8F:
+                return get_msgpack_object(static_cast<std::size_t>(current & 0x0F));
+
+            // fixarray
+            case 0x90:
+            case 0x91:
+            case 0x92:
+            case 0x93:
+            case 0x94:
+            case 0x95:
+            case 0x96:
+            case 0x97:
+            case 0x98:
+            case 0x99:
+            case 0x9A:
+            case 0x9B:
+            case 0x9C:
+            case 0x9D:
+            case 0x9E:
+            case 0x9F:
+                return get_msgpack_array(static_cast<std::size_t>(current & 0x0F));
+
+            // fixstr
+            case 0xA0:
+            case 0xA1:
+            case 0xA2:
+            case 0xA3:
+            case 0xA4:
+            case 0xA5:
+            case 0xA6:
+            case 0xA7:
+            case 0xA8:
+            case 0xA9:
+            case 0xAA:
+            case 0xAB:
+            case 0xAC:
+            case 0xAD:
+            case 0xAE:
+            case 0xAF:
+            case 0xB0:
+            case 0xB1:
+            case 0xB2:
+            case 0xB3:
+            case 0xB4:
+            case 0xB5:
+            case 0xB6:
+            case 0xB7:
+            case 0xB8:
+            case 0xB9:
+            case 0xBA:
+            case 0xBB:
+            case 0xBC:
+            case 0xBD:
+            case 0xBE:
+            case 0xBF:
+            {
+                string_t s;
+                return get_msgpack_string(s) and sax->string(s);
+            }
+
+            case 0xC0: // nil
+                return sax->null();
+
+            case 0xC2: // false
+                return sax->boolean(false);
+
+            case 0xC3: // true
+                return sax->boolean(true);
+
+            case 0xCA: // float 32
+            {
+                float number;
+                return get_number(input_format_t::msgpack, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            case 0xCB: // float 64
+            {
+                double number;
+                return get_number(input_format_t::msgpack, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            case 0xCC: // uint 8
+            {
+                uint8_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+            }
+
+            case 0xCD: // uint 16
+            {
+                uint16_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+            }
+
+            case 0xCE: // uint 32
+            {
+                uint32_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+            }
+
+            case 0xCF: // uint 64
+            {
+                uint64_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_unsigned(number);
+            }
+
+            case 0xD0: // int 8
+            {
+                int8_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+            }
+
+            case 0xD1: // int 16
+            {
+                int16_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+            }
+
+            case 0xD2: // int 32
+            {
+                int32_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+            }
+
+            case 0xD3: // int 64
+            {
+                int64_t number;
+                return get_number(input_format_t::msgpack, number) and sax->number_integer(number);
+            }
+
+            case 0xD9: // str 8
+            case 0xDA: // str 16
+            case 0xDB: // str 32
+            {
+                string_t s;
+                return get_msgpack_string(s) and sax->string(s);
+            }
+
+            case 0xDC: // array 16
+            {
+                uint16_t len;
+                return get_number(input_format_t::msgpack, len) and get_msgpack_array(static_cast<std::size_t>(len));
+            }
+
+            case 0xDD: // array 32
+            {
+                uint32_t len;
+                return get_number(input_format_t::msgpack, len) and get_msgpack_array(static_cast<std::size_t>(len));
+            }
+
+            case 0xDE: // map 16
+            {
+                uint16_t len;
+                return get_number(input_format_t::msgpack, len) and get_msgpack_object(static_cast<std::size_t>(len));
+            }
+
+            case 0xDF: // map 32
+            {
+                uint32_t len;
+                return get_number(input_format_t::msgpack, len) and get_msgpack_object(static_cast<std::size_t>(len));
+            }
+
+            // negative fixint
+            case 0xE0:
+            case 0xE1:
+            case 0xE2:
+            case 0xE3:
+            case 0xE4:
+            case 0xE5:
+            case 0xE6:
+            case 0xE7:
+            case 0xE8:
+            case 0xE9:
+            case 0xEA:
+            case 0xEB:
+            case 0xEC:
+            case 0xED:
+            case 0xEE:
+            case 0xEF:
+            case 0xF0:
+            case 0xF1:
+            case 0xF2:
+            case 0xF3:
+            case 0xF4:
+            case 0xF5:
+            case 0xF6:
+            case 0xF7:
+            case 0xF8:
+            case 0xF9:
+            case 0xFA:
+            case 0xFB:
+            case 0xFC:
+            case 0xFD:
+            case 0xFE:
+            case 0xFF:
+                return sax->number_integer(static_cast<int8_t>(current));
+
+            default: // anything else
+            {
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::msgpack, "invalid byte: 0x" + last_token, "value")));
+            }
+        }
+    }
+
+    /*!
+    @brief reads a MessagePack string
+
+    This function first reads starting bytes to determine the expected
+    string length and then copies this number of bytes into a string.
+
+    @param[out] result  created string
+
+    @return whether string creation completed
+    */
+    bool get_msgpack_string(string_t& result)
+    {
+        if (JSON_UNLIKELY(not unexpect_eof(input_format_t::msgpack, "string")))
+        {
+            return false;
+        }
+
+        switch (current)
+        {
+            // fixstr
+            case 0xA0:
+            case 0xA1:
+            case 0xA2:
+            case 0xA3:
+            case 0xA4:
+            case 0xA5:
+            case 0xA6:
+            case 0xA7:
+            case 0xA8:
+            case 0xA9:
+            case 0xAA:
+            case 0xAB:
+            case 0xAC:
+            case 0xAD:
+            case 0xAE:
+            case 0xAF:
+            case 0xB0:
+            case 0xB1:
+            case 0xB2:
+            case 0xB3:
+            case 0xB4:
+            case 0xB5:
+            case 0xB6:
+            case 0xB7:
+            case 0xB8:
+            case 0xB9:
+            case 0xBA:
+            case 0xBB:
+            case 0xBC:
+            case 0xBD:
+            case 0xBE:
+            case 0xBF:
+            {
+                return get_string(input_format_t::msgpack, current & 0x1F, result);
+            }
+
+            case 0xD9: // str 8
+            {
+                uint8_t len;
+                return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
+            }
+
+            case 0xDA: // str 16
+            {
+                uint16_t len;
+                return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
+            }
+
+            case 0xDB: // str 32
+            {
+                uint32_t len;
+                return get_number(input_format_t::msgpack, len) and get_string(input_format_t::msgpack, len, result);
+            }
+
+            default:
+            {
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::msgpack, "expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0x" + last_token, "string")));
+            }
+        }
+    }
+
+    /*!
+    @param[in] len  the length of the array
+    @return whether array creation completed
+    */
+    bool get_msgpack_array(const std::size_t len)
+    {
+        if (JSON_UNLIKELY(not sax->start_array(len)))
+        {
+            return false;
+        }
+
+        for (std::size_t i = 0; i < len; ++i)
+        {
+            if (JSON_UNLIKELY(not parse_msgpack_internal()))
+            {
+                return false;
+            }
+        }
+
+        return sax->end_array();
+    }
+
+    /*!
+    @param[in] len  the length of the object
+    @return whether object creation completed
+    */
+    bool get_msgpack_object(const std::size_t len)
+    {
+        if (JSON_UNLIKELY(not sax->start_object(len)))
+        {
+            return false;
+        }
+
+        string_t key;
+        for (std::size_t i = 0; i < len; ++i)
+        {
+            get();
+            if (JSON_UNLIKELY(not get_msgpack_string(key) or not sax->key(key)))
+            {
+                return false;
+            }
+
+            if (JSON_UNLIKELY(not parse_msgpack_internal()))
+            {
+                return false;
+            }
+            key.clear();
+        }
+
+        return sax->end_object();
+    }
+
+    ////////////
+    // UBJSON //
+    ////////////
+
+    /*!
+    @param[in] get_char  whether a new character should be retrieved from the
+                         input (true, default) or whether the last read
+                         character should be considered instead
+
+    @return whether a valid UBJSON value was passed to the SAX parser
+    */
+    bool parse_ubjson_internal(const bool get_char = true)
+    {
+        return get_ubjson_value(get_char ? get_ignore_noop() : current);
+    }
+
+    /*!
+    @brief reads a UBJSON string
+
+    This function is either called after reading the 'S' byte explicitly
+    indicating a string, or in case of an object key where the 'S' byte can be
+    left out.
+
+    @param[out] result   created string
+    @param[in] get_char  whether a new character should be retrieved from the
+                         input (true, default) or whether the last read
+                         character should be considered instead
+
+    @return whether string creation completed
+    */
+    bool get_ubjson_string(string_t& result, const bool get_char = true)
+    {
+        if (get_char)
+        {
+            get();  // TODO: may we ignore N here?
+        }
+
+        if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "value")))
+        {
+            return false;
+        }
+
+        switch (current)
+        {
+            case 'U':
+            {
+                uint8_t len;
+                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+            }
+
+            case 'i':
+            {
+                int8_t len;
+                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+            }
+
+            case 'I':
+            {
+                int16_t len;
+                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+            }
+
+            case 'l':
+            {
+                int32_t len;
+                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+            }
+
+            case 'L':
+            {
+                int64_t len;
+                return get_number(input_format_t::ubjson, len) and get_string(input_format_t::ubjson, len, result);
+            }
+
+            default:
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L); last byte: 0x" + last_token, "string")));
+        }
+    }
+
+    /*!
+    @param[out] result  determined size
+    @return whether size determination completed
+    */
+    bool get_ubjson_size_value(std::size_t& result)
+    {
+        switch (get_ignore_noop())
+        {
+            case 'U':
+            {
+                uint8_t number;
+                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+                {
+                    return false;
+                }
+                result = static_cast<std::size_t>(number);
+                return true;
+            }
+
+            case 'i':
+            {
+                int8_t number;
+                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+                {
+                    return false;
+                }
+                result = static_cast<std::size_t>(number);
+                return true;
+            }
+
+            case 'I':
+            {
+                int16_t number;
+                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+                {
+                    return false;
+                }
+                result = static_cast<std::size_t>(number);
+                return true;
+            }
+
+            case 'l':
+            {
+                int32_t number;
+                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+                {
+                    return false;
+                }
+                result = static_cast<std::size_t>(number);
+                return true;
+            }
+
+            case 'L':
+            {
+                int64_t number;
+                if (JSON_UNLIKELY(not get_number(input_format_t::ubjson, number)))
+                {
+                    return false;
+                }
+                result = static_cast<std::size_t>(number);
+                return true;
+            }
+
+            default:
+            {
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L) after '#'; last byte: 0x" + last_token, "size")));
+            }
+        }
+    }
+
+    /*!
+    @brief determine the type and size for a container
+
+    In the optimized UBJSON format, a type and a size can be provided to allow
+    for a more compact representation.
+
+    @param[out] result  pair of the size and the type
+
+    @return whether pair creation completed
+    */
+    bool get_ubjson_size_type(std::pair<std::size_t, int>& result)
+    {
+        result.first = string_t::npos; // size
+        result.second = 0; // type
+
+        get_ignore_noop();
+
+        if (current == '$')
+        {
+            result.second = get();  // must not ignore 'N', because 'N' maybe the type
+            if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "type")))
+            {
+                return false;
+            }
+
+            get_ignore_noop();
+            if (JSON_UNLIKELY(current != '#'))
+            {
+                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "value")))
+                {
+                    return false;
+                }
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::ubjson, "expected '#' after type information; last byte: 0x" + last_token, "size")));
+            }
+
+            return get_ubjson_size_value(result.first);
+        }
+        else if (current == '#')
+        {
+            return get_ubjson_size_value(result.first);
+        }
+        return true;
+    }
+
+    /*!
+    @param prefix  the previously read or set type prefix
+    @return whether value creation completed
+    */
+    bool get_ubjson_value(const int prefix)
+    {
+        switch (prefix)
+        {
+            case std::char_traits<char>::eof():  // EOF
+                return unexpect_eof(input_format_t::ubjson, "value");
+
+            case 'T':  // true
+                return sax->boolean(true);
+            case 'F':  // false
+                return sax->boolean(false);
+
+            case 'Z':  // null
+                return sax->null();
+
+            case 'U':
+            {
+                uint8_t number;
+                return get_number(input_format_t::ubjson, number) and sax->number_unsigned(number);
+            }
+
+            case 'i':
+            {
+                int8_t number;
+                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+            }
+
+            case 'I':
+            {
+                int16_t number;
+                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+            }
+
+            case 'l':
+            {
+                int32_t number;
+                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+            }
+
+            case 'L':
+            {
+                int64_t number;
+                return get_number(input_format_t::ubjson, number) and sax->number_integer(number);
+            }
+
+            case 'd':
+            {
+                float number;
+                return get_number(input_format_t::ubjson, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            case 'D':
+            {
+                double number;
+                return get_number(input_format_t::ubjson, number) and sax->number_float(static_cast<number_float_t>(number), "");
+            }
+
+            case 'C':  // char
+            {
+                get();
+                if (JSON_UNLIKELY(not unexpect_eof(input_format_t::ubjson, "char")))
+                {
+                    return false;
+                }
+                if (JSON_UNLIKELY(current > 127))
+                {
+                    auto last_token = get_token_string();
+                    return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "byte after 'C' must be in range 0x00..0x7F; last byte: 0x" + last_token, "char")));
+                }
+                string_t s(1, static_cast<char>(current));
+                return sax->string(s);
+            }
+
+            case 'S':  // string
+            {
+                string_t s;
+                return get_ubjson_string(s) and sax->string(s);
+            }
+
+            case '[':  // array
+                return get_ubjson_array();
+
+            case '{':  // object
+                return get_ubjson_object();
+
+            default: // anything else
+            {
+                auto last_token = get_token_string();
+                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::ubjson, "invalid byte: 0x" + last_token, "value")));
+            }
+        }
+    }
+
+    /*!
+    @return whether array creation completed
+    */
+    bool get_ubjson_array()
+    {
+        std::pair<std::size_t, int> size_and_type;
+        if (JSON_UNLIKELY(not get_ubjson_size_type(size_and_type)))
+        {
+            return false;
+        }
+
+        if (size_and_type.first != string_t::npos)
+        {
+            if (JSON_UNLIKELY(not sax->start_array(size_and_type.first)))
+            {
+                return false;
+            }
+
+            if (size_and_type.second != 0)
+            {
+                if (size_and_type.second != 'N')
+                {
+                    for (std::size_t i = 0; i < size_and_type.first; ++i)
+                    {
+                        if (JSON_UNLIKELY(not get_ubjson_value(size_and_type.second)))
+                        {
+                            return false;
+                        }
+                    }
+                }
+            }
+            else
+            {
+                for (std::size_t i = 0; i < size_and_type.first; ++i)
+                {
+                    if (JSON_UNLIKELY(not parse_ubjson_internal()))
+                    {
+                        return false;
+                    }
+                }
+            }
+        }
+        else
+        {
+            if (JSON_UNLIKELY(not sax->start_array(std::size_t(-1))))
+            {
+                return false;
+            }
+
+            while (current != ']')
+            {
+                if (JSON_UNLIKELY(not parse_ubjson_internal(false)))
+                {
+                    return false;
+                }
+                get_ignore_noop();
+            }
+        }
+
+        return sax->end_array();
+    }
+
+    /*!
+    @return whether object creation completed
+    */
+    bool get_ubjson_object()
+    {
+        std::pair<std::size_t, int> size_and_type;
+        if (JSON_UNLIKELY(not get_ubjson_size_type(size_and_type)))
+        {
+            return false;
+        }
+
+        string_t key;
+        if (size_and_type.first != string_t::npos)
+        {
+            if (JSON_UNLIKELY(not sax->start_object(size_and_type.first)))
+            {
+                return false;
+            }
+
+            if (size_and_type.second != 0)
+            {
+                for (std::size_t i = 0; i < size_and_type.first; ++i)
+                {
+                    if (JSON_UNLIKELY(not get_ubjson_string(key) or not sax->key(key)))
+                    {
+                        return false;
+                    }
+                    if (JSON_UNLIKELY(not get_ubjson_value(size_and_type.second)))
+                    {
+                        return false;
+                    }
+                    key.clear();
+                }
+            }
+            else
+            {
+                for (std::size_t i = 0; i < size_and_type.first; ++i)
+                {
+                    if (JSON_UNLIKELY(not get_ubjson_string(key) or not sax->key(key)))
+                    {
+                        return false;
+                    }
+                    if (JSON_UNLIKELY(not parse_ubjson_internal()))
+                    {
+                        return false;
+                    }
+                    key.clear();
+                }
+            }
+        }
+        else
+        {
+            if (JSON_UNLIKELY(not sax->start_object(std::size_t(-1))))
+            {
+                return false;
+            }
+
+            while (current != '}')
+            {
+                if (JSON_UNLIKELY(not get_ubjson_string(key, false) or not sax->key(key)))
+                {
+                    return false;
+                }
+                if (JSON_UNLIKELY(not parse_ubjson_internal()))
+                {
+                    return false;
+                }
+                get_ignore_noop();
+                key.clear();
+            }
+        }
+
+        return sax->end_object();
+    }
+
+    ///////////////////////
+    // Utility functions //
+    ///////////////////////
+
+    /*!
+    @brief get next character from the input
+
+    This function provides the interface to the used input adapter. It does
+    not throw in case the input reached EOF, but returns a -'ve valued
+    `std::char_traits<char>::eof()` in that case.
+
+    @return character read from the input
+    */
+    int get()
+    {
+        ++chars_read;
+        return (current = ia->get_character());
+    }
+
+    /*!
+    @return character read from the input after ignoring all 'N' entries
+    */
+    int get_ignore_noop()
+    {
+        do
+        {
+            get();
+        }
+        while (current == 'N');
+
+        return current;
+    }
+
+    /*
+    @brief read a number from the input
+
+    @tparam NumberType the type of the number
+    @param[in] format   the current format (for diagnostics)
+    @param[out] result  number of type @a NumberType
+
+    @return whether conversion completed
+
+    @note This function needs to respect the system's endianess, because
+          bytes in CBOR, MessagePack, and UBJSON are stored in network order
+          (big endian) and therefore need reordering on little endian systems.
+    */
+    template<typename NumberType, bool InputIsLittleEndian = false>
+    bool get_number(const input_format_t format, NumberType& result)
+    {
+        // step 1: read input into array with system's byte order
+        std::array<uint8_t, sizeof(NumberType)> vec;
+        for (std::size_t i = 0; i < sizeof(NumberType); ++i)
+        {
+            get();
+            if (JSON_UNLIKELY(not unexpect_eof(format, "number")))
+            {
+                return false;
+            }
+
+            // reverse byte order prior to conversion if necessary
+            if (is_little_endian && !InputIsLittleEndian)
+            {
+                vec[sizeof(NumberType) - i - 1] = static_cast<uint8_t>(current);
+            }
+            else
+            {
+                vec[i] = static_cast<uint8_t>(current); // LCOV_EXCL_LINE
+            }
+        }
+
+        // step 2: convert array into number of type T and return
+        std::memcpy(&result, vec.data(), sizeof(NumberType));
+        return true;
+    }
+
+    /*!
+    @brief create a string by reading characters from the input
+
+    @tparam NumberType the type of the number
+    @param[in] format the current format (for diagnostics)
+    @param[in] len number of characters to read
+    @param[out] result string created by reading @a len bytes
+
+    @return whether string creation completed
+
+    @note We can not reserve @a len bytes for the result, because @a len
+          may be too large. Usually, @ref unexpect_eof() detects the end of
+          the input before we run out of string memory.
+    */
+    template<typename NumberType>
+    bool get_string(const input_format_t format,
+                    const NumberType len,
+                    string_t& result)
+    {
+        bool success = true;
+        std::generate_n(std::back_inserter(result), len, [this, &success, &format]()
+        {
+            get();
+            if (JSON_UNLIKELY(not unexpect_eof(format, "string")))
+            {
+                success = false;
+            }
+            return static_cast<char>(current);
+        });
+        return success;
+    }
+
+    /*!
+    @param[in] format   the current format (for diagnostics)
+    @param[in] context  further context information (for diagnostics)
+    @return whether the last read character is not EOF
+    */
+    bool unexpect_eof(const input_format_t format, const char* context) const
+    {
+        if (JSON_UNLIKELY(current == std::char_traits<char>::eof()))
+        {
+            return sax->parse_error(chars_read, "<end of file>",
+                                    parse_error::create(110, chars_read, exception_message(format, "unexpected end of input", context)));
+        }
+        return true;
+    }
+
+    /*!
+    @return a string representation of the last read byte
+    */
+    std::string get_token_string() const
+    {
+        char cr[3];
+        (std::snprintf)(cr, 3, "%.2hhX", static_cast<unsigned char>(current));
+        return std::string{cr};
+    }
+
+    /*!
+    @param[in] format   the current format
+    @param[in] detail   a detailed error message
+    @param[in] context  further contect information
+    @return a message string to use in the parse_error exceptions
+    */
+    std::string exception_message(const input_format_t format,
+                                  const std::string& detail,
+                                  const std::string& context) const
+    {
+        std::string error_msg = "syntax error while parsing ";
+
+        switch (format)
+        {
+            case input_format_t::cbor:
+                error_msg += "CBOR";
+                break;
+
+            case input_format_t::msgpack:
+                error_msg += "MessagePack";
+                break;
+
+            case input_format_t::ubjson:
+                error_msg += "UBJSON";
+                break;
+
+            case input_format_t::bson:
+                error_msg += "BSON";
+                break;
+
+            // LCOV_EXCL_START
+            default:
+                assert(false);
+                // LCOV_EXCL_STOP
+        }
+
+        return error_msg + " " + context + ": " + detail;
+    }
+
+  private:
+    /// input adapter
+    input_adapter_t ia = nullptr;
+
+    /// the current character
+    int current = std::char_traits<char>::eof();
+
+    /// the number of characters read
+    std::size_t chars_read = 0;
+
+    /// whether we can assume little endianess
+    const bool is_little_endian = little_endianess();
+
+    /// the SAX parser
+    json_sax_t* sax = nullptr;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/output/binary_writer.hpp>
+
+
+#include <algorithm> // reverse
+#include <array> // array
+#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t
+#include <cstring> // memcpy
+#include <limits> // numeric_limits
+
+// #include <nlohmann/detail/input/binary_reader.hpp>
+
+// #include <nlohmann/detail/output/output_adapters.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+///////////////////
+// binary writer //
+///////////////////
+
+/*!
+@brief serialization to CBOR and MessagePack values
+*/
+template<typename BasicJsonType, typename CharType>
+class binary_writer
+{
+    using string_t = typename BasicJsonType::string_t;
+
+  public:
+    /*!
+    @brief create a binary writer
+
+    @param[in] adapter  output adapter to write to
+    */
+    explicit binary_writer(output_adapter_t<CharType> adapter) : oa(adapter)
+    {
+        assert(oa);
+    }
+
+    /*!
+    @param[in] j  JSON value to serialize
+    @pre       j.type() == value_t::object
+    */
+    void write_bson(const BasicJsonType& j)
+    {
+        switch (j.type())
+        {
+            case value_t::object:
+            {
+                write_bson_object(*j.m_value.object);
+                break;
+            }
+
+            default:
+            {
+                JSON_THROW(type_error::create(317, "to serialize to BSON, top-level type must be object, but is " + std::string(j.type_name())));
+            }
+        }
+    }
+
+    /*!
+    @param[in] j  JSON value to serialize
+    */
+    void write_cbor(const BasicJsonType& j)
+    {
+        switch (j.type())
+        {
+            case value_t::null:
+            {
+                oa->write_character(to_char_type(0xF6));
+                break;
+            }
+
+            case value_t::boolean:
+            {
+                oa->write_character(j.m_value.boolean
+                                    ? to_char_type(0xF5)
+                                    : to_char_type(0xF4));
+                break;
+            }
+
+            case value_t::number_integer:
+            {
+                if (j.m_value.number_integer >= 0)
+                {
+                    // CBOR does not differentiate between positive signed
+                    // integers and unsigned integers. Therefore, we used the
+                    // code from the value_t::number_unsigned case here.
+                    if (j.m_value.number_integer <= 0x17)
+                    {
+                        write_number(static_cast<uint8_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer <= (std::numeric_limits<uint8_t>::max)())
+                    {
+                        oa->write_character(to_char_type(0x18));
+                        write_number(static_cast<uint8_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer <= (std::numeric_limits<uint16_t>::max)())
+                    {
+                        oa->write_character(to_char_type(0x19));
+                        write_number(static_cast<uint16_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer <= (std::numeric_limits<uint32_t>::max)())
+                    {
+                        oa->write_character(to_char_type(0x1A));
+                        write_number(static_cast<uint32_t>(j.m_value.number_integer));
+                    }
+                    else
+                    {
+                        oa->write_character(to_char_type(0x1B));
+                        write_number(static_cast<uint64_t>(j.m_value.number_integer));
+                    }
+                }
+                else
+                {
+                    // The conversions below encode the sign in the first
+                    // byte, and the value is converted to a positive number.
+                    const auto positive_number = -1 - j.m_value.number_integer;
+                    if (j.m_value.number_integer >= -24)
+                    {
+                        write_number(static_cast<uint8_t>(0x20 + positive_number));
+                    }
+                    else if (positive_number <= (std::numeric_limits<uint8_t>::max)())
+                    {
+                        oa->write_character(to_char_type(0x38));
+                        write_number(static_cast<uint8_t>(positive_number));
+                    }
+                    else if (positive_number <= (std::numeric_limits<uint16_t>::max)())
+                    {
+                        oa->write_character(to_char_type(0x39));
+                        write_number(static_cast<uint16_t>(positive_number));
+                    }
+                    else if (positive_number <= (std::numeric_limits<uint32_t>::max)())
+                    {
+                        oa->write_character(to_char_type(0x3A));
+                        write_number(static_cast<uint32_t>(positive_number));
+                    }
+                    else
+                    {
+                        oa->write_character(to_char_type(0x3B));
+                        write_number(static_cast<uint64_t>(positive_number));
+                    }
+                }
+                break;
+            }
+
+            case value_t::number_unsigned:
+            {
+                if (j.m_value.number_unsigned <= 0x17)
+                {
+                    write_number(static_cast<uint8_t>(j.m_value.number_unsigned));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x18));
+                    write_number(static_cast<uint8_t>(j.m_value.number_unsigned));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x19));
+                    write_number(static_cast<uint16_t>(j.m_value.number_unsigned));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x1A));
+                    write_number(static_cast<uint32_t>(j.m_value.number_unsigned));
+                }
+                else
+                {
+                    oa->write_character(to_char_type(0x1B));
+                    write_number(static_cast<uint64_t>(j.m_value.number_unsigned));
+                }
+                break;
+            }
+
+            case value_t::number_float:
+            {
+                oa->write_character(get_cbor_float_prefix(j.m_value.number_float));
+                write_number(j.m_value.number_float);
+                break;
+            }
+
+            case value_t::string:
+            {
+                // step 1: write control byte and the string length
+                const auto N = j.m_value.string->size();
+                if (N <= 0x17)
+                {
+                    write_number(static_cast<uint8_t>(0x60 + N));
+                }
+                else if (N <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x78));
+                    write_number(static_cast<uint8_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x79));
+                    write_number(static_cast<uint16_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x7A));
+                    write_number(static_cast<uint32_t>(N));
+                }
+                // LCOV_EXCL_START
+                else if (N <= (std::numeric_limits<uint64_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x7B));
+                    write_number(static_cast<uint64_t>(N));
+                }
+                // LCOV_EXCL_STOP
+
+                // step 2: write the string
+                oa->write_characters(
+                    reinterpret_cast<const CharType*>(j.m_value.string->c_str()),
+                    j.m_value.string->size());
+                break;
+            }
+
+            case value_t::array:
+            {
+                // step 1: write control byte and the array size
+                const auto N = j.m_value.array->size();
+                if (N <= 0x17)
+                {
+                    write_number(static_cast<uint8_t>(0x80 + N));
+                }
+                else if (N <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x98));
+                    write_number(static_cast<uint8_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x99));
+                    write_number(static_cast<uint16_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x9A));
+                    write_number(static_cast<uint32_t>(N));
+                }
+                // LCOV_EXCL_START
+                else if (N <= (std::numeric_limits<uint64_t>::max)())
+                {
+                    oa->write_character(to_char_type(0x9B));
+                    write_number(static_cast<uint64_t>(N));
+                }
+                // LCOV_EXCL_STOP
+
+                // step 2: write each element
+                for (const auto& el : *j.m_value.array)
+                {
+                    write_cbor(el);
+                }
+                break;
+            }
+
+            case value_t::object:
+            {
+                // step 1: write control byte and the object size
+                const auto N = j.m_value.object->size();
+                if (N <= 0x17)
+                {
+                    write_number(static_cast<uint8_t>(0xA0 + N));
+                }
+                else if (N <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    oa->write_character(to_char_type(0xB8));
+                    write_number(static_cast<uint8_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    oa->write_character(to_char_type(0xB9));
+                    write_number(static_cast<uint16_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    oa->write_character(to_char_type(0xBA));
+                    write_number(static_cast<uint32_t>(N));
+                }
+                // LCOV_EXCL_START
+                else if (N <= (std::numeric_limits<uint64_t>::max)())
+                {
+                    oa->write_character(to_char_type(0xBB));
+                    write_number(static_cast<uint64_t>(N));
+                }
+                // LCOV_EXCL_STOP
+
+                // step 2: write each element
+                for (const auto& el : *j.m_value.object)
+                {
+                    write_cbor(el.first);
+                    write_cbor(el.second);
+                }
+                break;
+            }
+
+            default:
+                break;
+        }
+    }
+
+    /*!
+    @param[in] j  JSON value to serialize
+    */
+    void write_msgpack(const BasicJsonType& j)
+    {
+        switch (j.type())
+        {
+            case value_t::null: // nil
+            {
+                oa->write_character(to_char_type(0xC0));
+                break;
+            }
+
+            case value_t::boolean: // true and false
+            {
+                oa->write_character(j.m_value.boolean
+                                    ? to_char_type(0xC3)
+                                    : to_char_type(0xC2));
+                break;
+            }
+
+            case value_t::number_integer:
+            {
+                if (j.m_value.number_integer >= 0)
+                {
+                    // MessagePack does not differentiate between positive
+                    // signed integers and unsigned integers. Therefore, we used
+                    // the code from the value_t::number_unsigned case here.
+                    if (j.m_value.number_unsigned < 128)
+                    {
+                        // positive fixnum
+                        write_number(static_cast<uint8_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)())
+                    {
+                        // uint 8
+                        oa->write_character(to_char_type(0xCC));
+                        write_number(static_cast<uint8_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)())
+                    {
+                        // uint 16
+                        oa->write_character(to_char_type(0xCD));
+                        write_number(static_cast<uint16_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)())
+                    {
+                        // uint 32
+                        oa->write_character(to_char_type(0xCE));
+                        write_number(static_cast<uint32_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_unsigned <= (std::numeric_limits<uint64_t>::max)())
+                    {
+                        // uint 64
+                        oa->write_character(to_char_type(0xCF));
+                        write_number(static_cast<uint64_t>(j.m_value.number_integer));
+                    }
+                }
+                else
+                {
+                    if (j.m_value.number_integer >= -32)
+                    {
+                        // negative fixnum
+                        write_number(static_cast<int8_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer >= (std::numeric_limits<int8_t>::min)() and
+                             j.m_value.number_integer <= (std::numeric_limits<int8_t>::max)())
+                    {
+                        // int 8
+                        oa->write_character(to_char_type(0xD0));
+                        write_number(static_cast<int8_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer >= (std::numeric_limits<int16_t>::min)() and
+                             j.m_value.number_integer <= (std::numeric_limits<int16_t>::max)())
+                    {
+                        // int 16
+                        oa->write_character(to_char_type(0xD1));
+                        write_number(static_cast<int16_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer >= (std::numeric_limits<int32_t>::min)() and
+                             j.m_value.number_integer <= (std::numeric_limits<int32_t>::max)())
+                    {
+                        // int 32
+                        oa->write_character(to_char_type(0xD2));
+                        write_number(static_cast<int32_t>(j.m_value.number_integer));
+                    }
+                    else if (j.m_value.number_integer >= (std::numeric_limits<int64_t>::min)() and
+                             j.m_value.number_integer <= (std::numeric_limits<int64_t>::max)())
+                    {
+                        // int 64
+                        oa->write_character(to_char_type(0xD3));
+                        write_number(static_cast<int64_t>(j.m_value.number_integer));
+                    }
+                }
+                break;
+            }
+
+            case value_t::number_unsigned:
+            {
+                if (j.m_value.number_unsigned < 128)
+                {
+                    // positive fixnum
+                    write_number(static_cast<uint8_t>(j.m_value.number_integer));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    // uint 8
+                    oa->write_character(to_char_type(0xCC));
+                    write_number(static_cast<uint8_t>(j.m_value.number_integer));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    // uint 16
+                    oa->write_character(to_char_type(0xCD));
+                    write_number(static_cast<uint16_t>(j.m_value.number_integer));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    // uint 32
+                    oa->write_character(to_char_type(0xCE));
+                    write_number(static_cast<uint32_t>(j.m_value.number_integer));
+                }
+                else if (j.m_value.number_unsigned <= (std::numeric_limits<uint64_t>::max)())
+                {
+                    // uint 64
+                    oa->write_character(to_char_type(0xCF));
+                    write_number(static_cast<uint64_t>(j.m_value.number_integer));
+                }
+                break;
+            }
+
+            case value_t::number_float:
+            {
+                oa->write_character(get_msgpack_float_prefix(j.m_value.number_float));
+                write_number(j.m_value.number_float);
+                break;
+            }
+
+            case value_t::string:
+            {
+                // step 1: write control byte and the string length
+                const auto N = j.m_value.string->size();
+                if (N <= 31)
+                {
+                    // fixstr
+                    write_number(static_cast<uint8_t>(0xA0 | N));
+                }
+                else if (N <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    // str 8
+                    oa->write_character(to_char_type(0xD9));
+                    write_number(static_cast<uint8_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    // str 16
+                    oa->write_character(to_char_type(0xDA));
+                    write_number(static_cast<uint16_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    // str 32
+                    oa->write_character(to_char_type(0xDB));
+                    write_number(static_cast<uint32_t>(N));
+                }
+
+                // step 2: write the string
+                oa->write_characters(
+                    reinterpret_cast<const CharType*>(j.m_value.string->c_str()),
+                    j.m_value.string->size());
+                break;
+            }
+
+            case value_t::array:
+            {
+                // step 1: write control byte and the array size
+                const auto N = j.m_value.array->size();
+                if (N <= 15)
+                {
+                    // fixarray
+                    write_number(static_cast<uint8_t>(0x90 | N));
+                }
+                else if (N <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    // array 16
+                    oa->write_character(to_char_type(0xDC));
+                    write_number(static_cast<uint16_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    // array 32
+                    oa->write_character(to_char_type(0xDD));
+                    write_number(static_cast<uint32_t>(N));
+                }
+
+                // step 2: write each element
+                for (const auto& el : *j.m_value.array)
+                {
+                    write_msgpack(el);
+                }
+                break;
+            }
+
+            case value_t::object:
+            {
+                // step 1: write control byte and the object size
+                const auto N = j.m_value.object->size();
+                if (N <= 15)
+                {
+                    // fixmap
+                    write_number(static_cast<uint8_t>(0x80 | (N & 0xF)));
+                }
+                else if (N <= (std::numeric_limits<uint16_t>::max)())
+                {
+                    // map 16
+                    oa->write_character(to_char_type(0xDE));
+                    write_number(static_cast<uint16_t>(N));
+                }
+                else if (N <= (std::numeric_limits<uint32_t>::max)())
+                {
+                    // map 32
+                    oa->write_character(to_char_type(0xDF));
+                    write_number(static_cast<uint32_t>(N));
+                }
+
+                // step 2: write each element
+                for (const auto& el : *j.m_value.object)
+                {
+                    write_msgpack(el.first);
+                    write_msgpack(el.second);
+                }
+                break;
+            }
+
+            default:
+                break;
+        }
+    }
+
+    /*!
+    @param[in] j  JSON value to serialize
+    @param[in] use_count   whether to use '#' prefixes (optimized format)
+    @param[in] use_type    whether to use '$' prefixes (optimized format)
+    @param[in] add_prefix  whether prefixes need to be used for this value
+    */
+    void write_ubjson(const BasicJsonType& j, const bool use_count,
+                      const bool use_type, const bool add_prefix = true)
+    {
+        switch (j.type())
+        {
+            case value_t::null:
+            {
+                if (add_prefix)
+                {
+                    oa->write_character(to_char_type('Z'));
+                }
+                break;
+            }
+
+            case value_t::boolean:
+            {
+                if (add_prefix)
+                {
+                    oa->write_character(j.m_value.boolean
+                                        ? to_char_type('T')
+                                        : to_char_type('F'));
+                }
+                break;
+            }
+
+            case value_t::number_integer:
+            {
+                write_number_with_ubjson_prefix(j.m_value.number_integer, add_prefix);
+                break;
+            }
+
+            case value_t::number_unsigned:
+            {
+                write_number_with_ubjson_prefix(j.m_value.number_unsigned, add_prefix);
+                break;
+            }
+
+            case value_t::number_float:
+            {
+                write_number_with_ubjson_prefix(j.m_value.number_float, add_prefix);
+                break;
+            }
+
+            case value_t::string:
+            {
+                if (add_prefix)
+                {
+                    oa->write_character(to_char_type('S'));
+                }
+                write_number_with_ubjson_prefix(j.m_value.string->size(), true);
+                oa->write_characters(
+                    reinterpret_cast<const CharType*>(j.m_value.string->c_str()),
+                    j.m_value.string->size());
+                break;
+            }
+
+            case value_t::array:
+            {
+                if (add_prefix)
+                {
+                    oa->write_character(to_char_type('['));
+                }
+
+                bool prefix_required = true;
+                if (use_type and not j.m_value.array->empty())
+                {
+                    assert(use_count);
+                    const CharType first_prefix = ubjson_prefix(j.front());
+                    const bool same_prefix = std::all_of(j.begin() + 1, j.end(),
+                                                         [this, first_prefix](const BasicJsonType & v)
+                    {
+                        return ubjson_prefix(v) == first_prefix;
+                    });
+
+                    if (same_prefix)
+                    {
+                        prefix_required = false;
+                        oa->write_character(to_char_type('$'));
+                        oa->write_character(first_prefix);
+                    }
+                }
+
+                if (use_count)
+                {
+                    oa->write_character(to_char_type('#'));
+                    write_number_with_ubjson_prefix(j.m_value.array->size(), true);
+                }
+
+                for (const auto& el : *j.m_value.array)
+                {
+                    write_ubjson(el, use_count, use_type, prefix_required);
+                }
+
+                if (not use_count)
+                {
+                    oa->write_character(to_char_type(']'));
+                }
+
+                break;
+            }
+
+            case value_t::object:
+            {
+                if (add_prefix)
+                {
+                    oa->write_character(to_char_type('{'));
+                }
+
+                bool prefix_required = true;
+                if (use_type and not j.m_value.object->empty())
+                {
+                    assert(use_count);
+                    const CharType first_prefix = ubjson_prefix(j.front());
+                    const bool same_prefix = std::all_of(j.begin(), j.end(),
+                                                         [this, first_prefix](const BasicJsonType & v)
+                    {
+                        return ubjson_prefix(v) == first_prefix;
+                    });
+
+                    if (same_prefix)
+                    {
+                        prefix_required = false;
+                        oa->write_character(to_char_type('$'));
+                        oa->write_character(first_prefix);
+                    }
+                }
+
+                if (use_count)
+                {
+                    oa->write_character(to_char_type('#'));
+                    write_number_with_ubjson_prefix(j.m_value.object->size(), true);
+                }
+
+                for (const auto& el : *j.m_value.object)
+                {
+                    write_number_with_ubjson_prefix(el.first.size(), true);
+                    oa->write_characters(
+                        reinterpret_cast<const CharType*>(el.first.c_str()),
+                        el.first.size());
+                    write_ubjson(el.second, use_count, use_type, prefix_required);
+                }
+
+                if (not use_count)
+                {
+                    oa->write_character(to_char_type('}'));
+                }
+
+                break;
+            }
+
+            default:
+                break;
+        }
+    }
+
+  private:
+    //////////
+    // BSON //
+    //////////
+
+    /*!
+    @return The size of a BSON document entry header, including the id marker
+            and the entry name size (and its null-terminator).
+    */
+    static std::size_t calc_bson_entry_header_size(const string_t& name)
+    {
+        const auto it = name.find(static_cast<typename string_t::value_type>(0));
+        if (JSON_UNLIKELY(it != BasicJsonType::string_t::npos))
+        {
+            JSON_THROW(out_of_range::create(409,
+                                            "BSON key cannot contain code point U+0000 (at byte " + std::to_string(it) + ")"));
+        }
+
+        return /*id*/ 1ul + name.size() + /*zero-terminator*/1u;
+    }
+
+    /*!
+    @brief Writes the given @a element_type and @a name to the output adapter
+    */
+    void write_bson_entry_header(const string_t& name,
+                                 const std::uint8_t element_type)
+    {
+        oa->write_character(to_char_type(element_type)); // boolean
+        oa->write_characters(
+            reinterpret_cast<const CharType*>(name.c_str()),
+            name.size() + 1u);
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and boolean value @a value
+    */
+    void write_bson_boolean(const string_t& name,
+                            const bool value)
+    {
+        write_bson_entry_header(name, 0x08);
+        oa->write_character(value ? to_char_type(0x01) : to_char_type(0x00));
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and double value @a value
+    */
+    void write_bson_double(const string_t& name,
+                           const double value)
+    {
+        write_bson_entry_header(name, 0x01);
+        write_number<double, true>(value);
+    }
+
+    /*!
+    @return The size of the BSON-encoded string in @a value
+    */
+    static std::size_t calc_bson_string_size(const string_t& value)
+    {
+        return sizeof(std::int32_t) + value.size() + 1ul;
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and string value @a value
+    */
+    void write_bson_string(const string_t& name,
+                           const string_t& value)
+    {
+        write_bson_entry_header(name, 0x02);
+
+        write_number<std::int32_t, true>(static_cast<std::int32_t>(value.size() + 1ul));
+        oa->write_characters(
+            reinterpret_cast<const CharType*>(value.c_str()),
+            value.size() + 1);
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and null value
+    */
+    void write_bson_null(const string_t& name)
+    {
+        write_bson_entry_header(name, 0x0A);
+    }
+
+    /*!
+    @return The size of the BSON-encoded integer @a value
+    */
+    static std::size_t calc_bson_integer_size(const std::int64_t value)
+    {
+        if ((std::numeric_limits<std::int32_t>::min)() <= value and value <= (std::numeric_limits<std::int32_t>::max)())
+        {
+            return sizeof(std::int32_t);
+        }
+        else
+        {
+            return sizeof(std::int64_t);
+        }
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and integer @a value
+    */
+    void write_bson_integer(const string_t& name,
+                            const std::int64_t value)
+    {
+        if ((std::numeric_limits<std::int32_t>::min)() <= value and value <= (std::numeric_limits<std::int32_t>::max)())
+        {
+            write_bson_entry_header(name, 0x10); // int32
+            write_number<std::int32_t, true>(static_cast<std::int32_t>(value));
+        }
+        else
+        {
+            write_bson_entry_header(name, 0x12); // int64
+            write_number<std::int64_t, true>(static_cast<std::int64_t>(value));
+        }
+    }
+
+    /*!
+    @return The size of the BSON-encoded unsigned integer in @a j
+    */
+    static constexpr std::size_t calc_bson_unsigned_size(const std::uint64_t value) noexcept
+    {
+        return (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)()))
+               ? sizeof(std::int32_t)
+               : sizeof(std::int64_t);
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and unsigned @a value
+    */
+    void write_bson_unsigned(const string_t& name,
+                             const std::uint64_t value)
+    {
+        if (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)()))
+        {
+            write_bson_entry_header(name, 0x10 /* int32 */);
+            write_number<std::int32_t, true>(static_cast<std::int32_t>(value));
+        }
+        else if (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int64_t>::max)()))
+        {
+            write_bson_entry_header(name, 0x12 /* int64 */);
+            write_number<std::int64_t, true>(static_cast<std::int64_t>(value));
+        }
+        else
+        {
+            JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(value) + " cannot be represented by BSON as it does not fit int64"));
+        }
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and object @a value
+    */
+    void write_bson_object_entry(const string_t& name,
+                                 const typename BasicJsonType::object_t& value)
+    {
+        write_bson_entry_header(name, 0x03); // object
+        write_bson_object(value);
+    }
+
+    /*!
+    @return The size of the BSON-encoded array @a value
+    */
+    static std::size_t calc_bson_array_size(const typename BasicJsonType::array_t& value)
+    {
+        std::size_t embedded_document_size = 0ul;
+        std::size_t array_index = 0ul;
+
+        for (const auto& el : value)
+        {
+            embedded_document_size += calc_bson_element_size(std::to_string(array_index++), el);
+        }
+
+        return sizeof(std::int32_t) + embedded_document_size + 1ul;
+    }
+
+    /*!
+    @brief Writes a BSON element with key @a name and array @a value
+    */
+    void write_bson_array(const string_t& name,
+                          const typename BasicJsonType::array_t& value)
+    {
+        write_bson_entry_header(name, 0x04); // array
+        write_number<std::int32_t, true>(static_cast<std::int32_t>(calc_bson_array_size(value)));
+
+        std::size_t array_index = 0ul;
+
+        for (const auto& el : value)
+        {
+            write_bson_element(std::to_string(array_index++), el);
+        }
+
+        oa->write_character(to_char_type(0x00));
+    }
+
+    /*!
+    @brief Calculates the size necessary to serialize the JSON value @a j with its @a name
+    @return The calculated size for the BSON document entry for @a j with the given @a name.
+    */
+    static std::size_t calc_bson_element_size(const string_t& name,
+            const BasicJsonType& j)
+    {
+        const auto header_size = calc_bson_entry_header_size(name);
+        switch (j.type())
+        {
+            case value_t::object:
+                return header_size + calc_bson_object_size(*j.m_value.object);
+
+            case value_t::array:
+                return header_size + calc_bson_array_size(*j.m_value.array);
+
+            case value_t::boolean:
+                return header_size + 1ul;
+
+            case value_t::number_float:
+                return header_size + 8ul;
+
+            case value_t::number_integer:
+                return header_size + calc_bson_integer_size(j.m_value.number_integer);
+
+            case value_t::number_unsigned:
+                return header_size + calc_bson_unsigned_size(j.m_value.number_unsigned);
+
+            case value_t::string:
+                return header_size + calc_bson_string_size(*j.m_value.string);
+
+            case value_t::null:
+                return header_size + 0ul;
+
+            // LCOV_EXCL_START
+            default:
+                assert(false);
+                return 0ul;
+                // LCOV_EXCL_STOP
+        };
+    }
+
+    /*!
+    @brief Serializes the JSON value @a j to BSON and associates it with the
+           key @a name.
+    @param name The name to associate with the JSON entity @a j within the
+                current BSON document
+    @return The size of the BSON entry
+    */
+    void write_bson_element(const string_t& name,
+                            const BasicJsonType& j)
+    {
+        switch (j.type())
+        {
+            case value_t::object:
+                return write_bson_object_entry(name, *j.m_value.object);
+
+            case value_t::array:
+                return write_bson_array(name, *j.m_value.array);
+
+            case value_t::boolean:
+                return write_bson_boolean(name, j.m_value.boolean);
+
+            case value_t::number_float:
+                return write_bson_double(name, j.m_value.number_float);
+
+            case value_t::number_integer:
+                return write_bson_integer(name, j.m_value.number_integer);
+
+            case value_t::number_unsigned:
+                return write_bson_unsigned(name, j.m_value.number_unsigned);
+
+            case value_t::string:
+                return write_bson_string(name, *j.m_value.string);
+
+            case value_t::null:
+                return write_bson_null(name);
+
+            // LCOV_EXCL_START
+            default:
+                assert(false);
+                return;
+                // LCOV_EXCL_STOP
+        };
+    }
+
+    /*!
+    @brief Calculates the size of the BSON serialization of the given
+           JSON-object @a j.
+    @param[in] j  JSON value to serialize
+    @pre       j.type() == value_t::object
+    */
+    static std::size_t calc_bson_object_size(const typename BasicJsonType::object_t& value)
+    {
+        std::size_t document_size = std::accumulate(value.begin(), value.end(), 0ul,
+                                    [](size_t result, const typename BasicJsonType::object_t::value_type & el)
+        {
+            return result += calc_bson_element_size(el.first, el.second);
+        });
+
+        return sizeof(std::int32_t) + document_size + 1ul;
+    }
+
+    /*!
+    @param[in] j  JSON value to serialize
+    @pre       j.type() == value_t::object
+    */
+    void write_bson_object(const typename BasicJsonType::object_t& value)
+    {
+        write_number<std::int32_t, true>(static_cast<std::int32_t>(calc_bson_object_size(value)));
+
+        for (const auto& el : value)
+        {
+            write_bson_element(el.first, el.second);
+        }
+
+        oa->write_character(to_char_type(0x00));
+    }
+
+    //////////
+    // CBOR //
+    //////////
+
+    static constexpr CharType get_cbor_float_prefix(float /*unused*/)
+    {
+        return to_char_type(0xFA);  // Single-Precision Float
+    }
+
+    static constexpr CharType get_cbor_float_prefix(double /*unused*/)
+    {
+        return to_char_type(0xFB);  // Double-Precision Float
+    }
+
+    /////////////
+    // MsgPack //
+    /////////////
+
+    static constexpr CharType get_msgpack_float_prefix(float /*unused*/)
+    {
+        return to_char_type(0xCA);  // float 32
+    }
+
+    static constexpr CharType get_msgpack_float_prefix(double /*unused*/)
+    {
+        return to_char_type(0xCB);  // float 64
+    }
+
+    ////////////
+    // UBJSON //
+    ////////////
+
+    // UBJSON: write number (floating point)
+    template<typename NumberType, typename std::enable_if<
+                 std::is_floating_point<NumberType>::value, int>::type = 0>
+    void write_number_with_ubjson_prefix(const NumberType n,
+                                         const bool add_prefix)
+    {
+        if (add_prefix)
+        {
+            oa->write_character(get_ubjson_float_prefix(n));
+        }
+        write_number(n);
+    }
+
+    // UBJSON: write number (unsigned integer)
+    template<typename NumberType, typename std::enable_if<
+                 std::is_unsigned<NumberType>::value, int>::type = 0>
+    void write_number_with_ubjson_prefix(const NumberType n,
+                                         const bool add_prefix)
+    {
+        if (n <= static_cast<uint64_t>((std::numeric_limits<int8_t>::max)()))
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('i'));  // int8
+            }
+            write_number(static_cast<uint8_t>(n));
+        }
+        else if (n <= (std::numeric_limits<uint8_t>::max)())
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('U'));  // uint8
+            }
+            write_number(static_cast<uint8_t>(n));
+        }
+        else if (n <= static_cast<uint64_t>((std::numeric_limits<int16_t>::max)()))
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('I'));  // int16
+            }
+            write_number(static_cast<int16_t>(n));
+        }
+        else if (n <= static_cast<uint64_t>((std::numeric_limits<int32_t>::max)()))
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('l'));  // int32
+            }
+            write_number(static_cast<int32_t>(n));
+        }
+        else if (n <= static_cast<uint64_t>((std::numeric_limits<int64_t>::max)()))
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('L'));  // int64
+            }
+            write_number(static_cast<int64_t>(n));
+        }
+        else
+        {
+            JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(n) + " cannot be represented by UBJSON as it does not fit int64"));
+        }
+    }
+
+    // UBJSON: write number (signed integer)
+    template<typename NumberType, typename std::enable_if<
+                 std::is_signed<NumberType>::value and
+                 not std::is_floating_point<NumberType>::value, int>::type = 0>
+    void write_number_with_ubjson_prefix(const NumberType n,
+                                         const bool add_prefix)
+    {
+        if ((std::numeric_limits<int8_t>::min)() <= n and n <= (std::numeric_limits<int8_t>::max)())
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('i'));  // int8
+            }
+            write_number(static_cast<int8_t>(n));
+        }
+        else if (static_cast<int64_t>((std::numeric_limits<uint8_t>::min)()) <= n and n <= static_cast<int64_t>((std::numeric_limits<uint8_t>::max)()))
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('U'));  // uint8
+            }
+            write_number(static_cast<uint8_t>(n));
+        }
+        else if ((std::numeric_limits<int16_t>::min)() <= n and n <= (std::numeric_limits<int16_t>::max)())
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('I'));  // int16
+            }
+            write_number(static_cast<int16_t>(n));
+        }
+        else if ((std::numeric_limits<int32_t>::min)() <= n and n <= (std::numeric_limits<int32_t>::max)())
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('l'));  // int32
+            }
+            write_number(static_cast<int32_t>(n));
+        }
+        else if ((std::numeric_limits<int64_t>::min)() <= n and n <= (std::numeric_limits<int64_t>::max)())
+        {
+            if (add_prefix)
+            {
+                oa->write_character(to_char_type('L'));  // int64
+            }
+            write_number(static_cast<int64_t>(n));
+        }
+        // LCOV_EXCL_START
+        else
+        {
+            JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(n) + " cannot be represented by UBJSON as it does not fit int64"));
+        }
+        // LCOV_EXCL_STOP
+    }
+
+    /*!
+    @brief determine the type prefix of container values
+
+    @note This function does not need to be 100% accurate when it comes to
+          integer limits. In case a number exceeds the limits of int64_t,
+          this will be detected by a later call to function
+          write_number_with_ubjson_prefix. Therefore, we return 'L' for any
+          value that does not fit the previous limits.
+    */
+    CharType ubjson_prefix(const BasicJsonType& j) const noexcept
+    {
+        switch (j.type())
+        {
+            case value_t::null:
+                return 'Z';
+
+            case value_t::boolean:
+                return j.m_value.boolean ? 'T' : 'F';
+
+            case value_t::number_integer:
+            {
+                if ((std::numeric_limits<int8_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<int8_t>::max)())
+                {
+                    return 'i';
+                }
+                if ((std::numeric_limits<uint8_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    return 'U';
+                }
+                if ((std::numeric_limits<int16_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<int16_t>::max)())
+                {
+                    return 'I';
+                }
+                if ((std::numeric_limits<int32_t>::min)() <= j.m_value.number_integer and j.m_value.number_integer <= (std::numeric_limits<int32_t>::max)())
+                {
+                    return 'l';
+                }
+                // no check and assume int64_t (see note above)
+                return 'L';
+            }
+
+            case value_t::number_unsigned:
+            {
+                if (j.m_value.number_unsigned <= (std::numeric_limits<int8_t>::max)())
+                {
+                    return 'i';
+                }
+                if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)())
+                {
+                    return 'U';
+                }
+                if (j.m_value.number_unsigned <= (std::numeric_limits<int16_t>::max)())
+                {
+                    return 'I';
+                }
+                if (j.m_value.number_unsigned <= (std::numeric_limits<int32_t>::max)())
+                {
+                    return 'l';
+                }
+                // no check and assume int64_t (see note above)
+                return 'L';
+            }
+
+            case value_t::number_float:
+                return get_ubjson_float_prefix(j.m_value.number_float);
+
+            case value_t::string:
+                return 'S';
+
+            case value_t::array:
+                return '[';
+
+            case value_t::object:
+                return '{';
+
+            default:  // discarded values
+                return 'N';
+        }
+    }
+
+    static constexpr CharType get_ubjson_float_prefix(float /*unused*/)
+    {
+        return 'd';  // float 32
+    }
+
+    static constexpr CharType get_ubjson_float_prefix(double /*unused*/)
+    {
+        return 'D';  // float 64
+    }
+
+    ///////////////////////
+    // Utility functions //
+    ///////////////////////
+
+    /*
+    @brief write a number to output input
+    @param[in] n number of type @a NumberType
+    @tparam NumberType the type of the number
+    @tparam OutputIsLittleEndian Set to true if output data is
+                                 required to be little endian
+
+    @note This function needs to respect the system's endianess, because bytes
+          in CBOR, MessagePack, and UBJSON are stored in network order (big
+          endian) and therefore need reordering on little endian systems.
+    */
+    template<typename NumberType, bool OutputIsLittleEndian = false>
+    void write_number(const NumberType n)
+    {
+        // step 1: write number to array of length NumberType
+        std::array<CharType, sizeof(NumberType)> vec;
+        std::memcpy(vec.data(), &n, sizeof(NumberType));
+
+        // step 2: write array to output (with possible reordering)
+        if (is_little_endian and not OutputIsLittleEndian)
+        {
+            // reverse byte order prior to conversion if necessary
+            std::reverse(vec.begin(), vec.end());
+        }
+
+        oa->write_characters(vec.data(), sizeof(NumberType));
+    }
+
+  public:
+    // The following to_char_type functions are implement the conversion
+    // between uint8_t and CharType. In case CharType is not unsigned,
+    // such a conversion is required to allow values greater than 128.
+    // See <https://github.com/nlohmann/json/issues/1286> for a discussion.
+    template < typename C = CharType,
+               enable_if_t < std::is_signed<C>::value and std::is_signed<char>::value > * = nullptr >
+    static constexpr CharType to_char_type(std::uint8_t x) noexcept
+    {
+        return *reinterpret_cast<char*>(&x);
+    }
+
+    template < typename C = CharType,
+               enable_if_t < std::is_signed<C>::value and std::is_unsigned<char>::value > * = nullptr >
+    static CharType to_char_type(std::uint8_t x) noexcept
+    {
+        static_assert(sizeof(std::uint8_t) == sizeof(CharType), "size of CharType must be equal to std::uint8_t");
+        static_assert(std::is_pod<CharType>::value, "CharType must be POD");
+        CharType result;
+        std::memcpy(&result, &x, sizeof(x));
+        return result;
+    }
+
+    template<typename C = CharType,
+             enable_if_t<std::is_unsigned<C>::value>* = nullptr>
+    static constexpr CharType to_char_type(std::uint8_t x) noexcept
+    {
+        return x;
+    }
+
+    template < typename InputCharType, typename C = CharType,
+               enable_if_t <
+                   std::is_signed<C>::value and
+                   std::is_signed<char>::value and
+                   std::is_same<char, typename std::remove_cv<InputCharType>::type>::value
+                   > * = nullptr >
+    static constexpr CharType to_char_type(InputCharType x) noexcept
+    {
+        return x;
+    }
+
+  private:
+    /// whether we can assume little endianess
+    const bool is_little_endian = binary_reader<BasicJsonType>::little_endianess();
+
+    /// the output
+    output_adapter_t<CharType> oa = nullptr;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/output/serializer.hpp>
+
+
+#include <algorithm> // reverse, remove, fill, find, none_of
+#include <array> // array
+#include <cassert> // assert
+#include <ciso646> // and, or
+#include <clocale> // localeconv, lconv
+#include <cmath> // labs, isfinite, isnan, signbit
+#include <cstddef> // size_t, ptrdiff_t
+#include <cstdint> // uint8_t
+#include <cstdio> // snprintf
+#include <limits> // numeric_limits
+#include <string> // string
+#include <type_traits> // is_same
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+// #include <nlohmann/detail/conversions/to_chars.hpp>
+
+
+#include <cassert> // assert
+#include <ciso646> // or, and, not
+#include <cmath>   // signbit, isfinite
+#include <cstdint> // intN_t, uintN_t
+#include <cstring> // memcpy, memmove
+
+namespace nlohmann
+{
+namespace detail
+{
+
+/*!
+@brief implements the Grisu2 algorithm for binary to decimal floating-point
+conversion.
+
+This implementation is a slightly modified version of the reference
+implementation which may be obtained from
+http://florian.loitsch.com/publications (bench.tar.gz).
+
+The code is distributed under the MIT license, Copyright (c) 2009 Florian Loitsch.
+
+For a detailed description of the algorithm see:
+
+[1] Loitsch, "Printing Floating-Point Numbers Quickly and Accurately with
+    Integers", Proceedings of the ACM SIGPLAN 2010 Conference on Programming
+    Language Design and Implementation, PLDI 2010
+[2] Burger, Dybvig, "Printing Floating-Point Numbers Quickly and Accurately",
+    Proceedings of the ACM SIGPLAN 1996 Conference on Programming Language
+    Design and Implementation, PLDI 1996
+*/
+namespace dtoa_impl
+{
+
+template <typename Target, typename Source>
+Target reinterpret_bits(const Source source)
+{
+    static_assert(sizeof(Target) == sizeof(Source), "size mismatch");
+
+    Target target;
+    std::memcpy(&target, &source, sizeof(Source));
+    return target;
+}
+
+struct diyfp // f * 2^e
+{
+    static constexpr int kPrecision = 64; // = q
+
+    uint64_t f = 0;
+    int e = 0;
+
+    constexpr diyfp(uint64_t f_, int e_) noexcept : f(f_), e(e_) {}
+
+    /*!
+    @brief returns x - y
+    @pre x.e == y.e and x.f >= y.f
+    */
+    static diyfp sub(const diyfp& x, const diyfp& y) noexcept
+    {
+        assert(x.e == y.e);
+        assert(x.f >= y.f);
+
+        return {x.f - y.f, x.e};
+    }
+
+    /*!
+    @brief returns x * y
+    @note The result is rounded. (Only the upper q bits are returned.)
+    */
+    static diyfp mul(const diyfp& x, const diyfp& y) noexcept
+    {
+        static_assert(kPrecision == 64, "internal error");
+
+        // Computes:
+        //  f = round((x.f * y.f) / 2^q)
+        //  e = x.e + y.e + q
+
+        // Emulate the 64-bit * 64-bit multiplication:
+        //
+        // p = u * v
+        //   = (u_lo + 2^32 u_hi) (v_lo + 2^32 v_hi)
+        //   = (u_lo v_lo         ) + 2^32 ((u_lo v_hi         ) + (u_hi v_lo         )) + 2^64 (u_hi v_hi         )
+        //   = (p0                ) + 2^32 ((p1                ) + (p2                )) + 2^64 (p3                )
+        //   = (p0_lo + 2^32 p0_hi) + 2^32 ((p1_lo + 2^32 p1_hi) + (p2_lo + 2^32 p2_hi)) + 2^64 (p3                )
+        //   = (p0_lo             ) + 2^32 (p0_hi + p1_lo + p2_lo                      ) + 2^64 (p1_hi + p2_hi + p3)
+        //   = (p0_lo             ) + 2^32 (Q                                          ) + 2^64 (H                 )
+        //   = (p0_lo             ) + 2^32 (Q_lo + 2^32 Q_hi                           ) + 2^64 (H                 )
+        //
+        // (Since Q might be larger than 2^32 - 1)
+        //
+        //   = (p0_lo + 2^32 Q_lo) + 2^64 (Q_hi + H)
+        //
+        // (Q_hi + H does not overflow a 64-bit int)
+        //
+        //   = p_lo + 2^64 p_hi
+
+        const uint64_t u_lo = x.f & 0xFFFFFFFF;
+        const uint64_t u_hi = x.f >> 32;
+        const uint64_t v_lo = y.f & 0xFFFFFFFF;
+        const uint64_t v_hi = y.f >> 32;
+
+        const uint64_t p0 = u_lo * v_lo;
+        const uint64_t p1 = u_lo * v_hi;
+        const uint64_t p2 = u_hi * v_lo;
+        const uint64_t p3 = u_hi * v_hi;
+
+        const uint64_t p0_hi = p0 >> 32;
+        const uint64_t p1_lo = p1 & 0xFFFFFFFF;
+        const uint64_t p1_hi = p1 >> 32;
+        const uint64_t p2_lo = p2 & 0xFFFFFFFF;
+        const uint64_t p2_hi = p2 >> 32;
+
+        uint64_t Q = p0_hi + p1_lo + p2_lo;
+
+        // The full product might now be computed as
+        //
+        // p_hi = p3 + p2_hi + p1_hi + (Q >> 32)
+        // p_lo = p0_lo + (Q << 32)
+        //
+        // But in this particular case here, the full p_lo is not required.
+        // Effectively we only need to add the highest bit in p_lo to p_hi (and
+        // Q_hi + 1 does not overflow).
+
+        Q += uint64_t{1} << (64 - 32 - 1); // round, ties up
+
+        const uint64_t h = p3 + p2_hi + p1_hi + (Q >> 32);
+
+        return {h, x.e + y.e + 64};
+    }
+
+    /*!
+    @brief normalize x such that the significand is >= 2^(q-1)
+    @pre x.f != 0
+    */
+    static diyfp normalize(diyfp x) noexcept
+    {
+        assert(x.f != 0);
+
+        while ((x.f >> 63) == 0)
+        {
+            x.f <<= 1;
+            x.e--;
+        }
+
+        return x;
+    }
+
+    /*!
+    @brief normalize x such that the result has the exponent E
+    @pre e >= x.e and the upper e - x.e bits of x.f must be zero.
+    */
+    static diyfp normalize_to(const diyfp& x, const int target_exponent) noexcept
+    {
+        const int delta = x.e - target_exponent;
+
+        assert(delta >= 0);
+        assert(((x.f << delta) >> delta) == x.f);
+
+        return {x.f << delta, target_exponent};
+    }
+};
+
+struct boundaries
+{
+    diyfp w;
+    diyfp minus;
+    diyfp plus;
+};
+
+/*!
+Compute the (normalized) diyfp representing the input number 'value' and its
+boundaries.
+
+@pre value must be finite and positive
+*/
+template <typename FloatType>
+boundaries compute_boundaries(FloatType value)
+{
+    assert(std::isfinite(value));
+    assert(value > 0);
+
+    // Convert the IEEE representation into a diyfp.
+    //
+    // If v is denormal:
+    //      value = 0.F * 2^(1 - bias) = (          F) * 2^(1 - bias - (p-1))
+    // If v is normalized:
+    //      value = 1.F * 2^(E - bias) = (2^(p-1) + F) * 2^(E - bias - (p-1))
+
+    static_assert(std::numeric_limits<FloatType>::is_iec559,
+                  "internal error: dtoa_short requires an IEEE-754 floating-point implementation");
+
+    constexpr int      kPrecision = std::numeric_limits<FloatType>::digits; // = p (includes the hidden bit)
+    constexpr int      kBias      = std::numeric_limits<FloatType>::max_exponent - 1 + (kPrecision - 1);
+    constexpr int      kMinExp    = 1 - kBias;
+    constexpr uint64_t kHiddenBit = uint64_t{1} << (kPrecision - 1); // = 2^(p-1)
+
+    using bits_type = typename std::conditional< kPrecision == 24, uint32_t, uint64_t >::type;
+
+    const uint64_t bits = reinterpret_bits<bits_type>(value);
+    const uint64_t E = bits >> (kPrecision - 1);
+    const uint64_t F = bits & (kHiddenBit - 1);
+
+    const bool is_denormal = (E == 0);
+    const diyfp v = is_denormal
+                    ? diyfp(F, kMinExp)
+                    : diyfp(F + kHiddenBit, static_cast<int>(E) - kBias);
+
+    // Compute the boundaries m- and m+ of the floating-point value
+    // v = f * 2^e.
+    //
+    // Determine v- and v+, the floating-point predecessor and successor if v,
+    // respectively.
+    //
+    //      v- = v - 2^e        if f != 2^(p-1) or e == e_min                (A)
+    //         = v - 2^(e-1)    if f == 2^(p-1) and e > e_min                (B)
+    //
+    //      v+ = v + 2^e
+    //
+    // Let m- = (v- + v) / 2 and m+ = (v + v+) / 2. All real numbers _strictly_
+    // between m- and m+ round to v, regardless of how the input rounding
+    // algorithm breaks ties.
+    //
+    //      ---+-------------+-------------+-------------+-------------+---  (A)
+    //         v-            m-            v             m+            v+
+    //
+    //      -----------------+------+------+-------------+-------------+---  (B)
+    //                       v-     m-     v             m+            v+
+
+    const bool lower_boundary_is_closer = (F == 0 and E > 1);
+    const diyfp m_plus = diyfp(2 * v.f + 1, v.e - 1);
+    const diyfp m_minus = lower_boundary_is_closer
+                          ? diyfp(4 * v.f - 1, v.e - 2)  // (B)
+                          : diyfp(2 * v.f - 1, v.e - 1); // (A)
+
+    // Determine the normalized w+ = m+.
+    const diyfp w_plus = diyfp::normalize(m_plus);
+
+    // Determine w- = m- such that e_(w-) = e_(w+).
+    const diyfp w_minus = diyfp::normalize_to(m_minus, w_plus.e);
+
+    return {diyfp::normalize(v), w_minus, w_plus};
+}
+
+// Given normalized diyfp w, Grisu needs to find a (normalized) cached
+// power-of-ten c, such that the exponent of the product c * w = f * 2^e lies
+// within a certain range [alpha, gamma] (Definition 3.2 from [1])
+//
+//      alpha <= e = e_c + e_w + q <= gamma
+//
+// or
+//
+//      f_c * f_w * 2^alpha <= f_c 2^(e_c) * f_w 2^(e_w) * 2^q
+//                          <= f_c * f_w * 2^gamma
+//
+// Since c and w are normalized, i.e. 2^(q-1) <= f < 2^q, this implies
+//
+//      2^(q-1) * 2^(q-1) * 2^alpha <= c * w * 2^q < 2^q * 2^q * 2^gamma
+//
+// or
+//
+//      2^(q - 2 + alpha) <= c * w < 2^(q + gamma)
+//
+// The choice of (alpha,gamma) determines the size of the table and the form of
+// the digit generation procedure. Using (alpha,gamma)=(-60,-32) works out well
+// in practice:
+//
+// The idea is to cut the number c * w = f * 2^e into two parts, which can be
+// processed independently: An integral part p1, and a fractional part p2:
+//
+//      f * 2^e = ( (f div 2^-e) * 2^-e + (f mod 2^-e) ) * 2^e
+//              = (f div 2^-e) + (f mod 2^-e) * 2^e
+//              = p1 + p2 * 2^e
+//
+// The conversion of p1 into decimal form requires a series of divisions and
+// modulos by (a power of) 10. These operations are faster for 32-bit than for
+// 64-bit integers, so p1 should ideally fit into a 32-bit integer. This can be
+// achieved by choosing
+//
+//      -e >= 32   or   e <= -32 := gamma
+//
+// In order to convert the fractional part
+//
+//      p2 * 2^e = p2 / 2^-e = d[-1] / 10^1 + d[-2] / 10^2 + ...
+//
+// into decimal form, the fraction is repeatedly multiplied by 10 and the digits
+// d[-i] are extracted in order:
+//
+//      (10 * p2) div 2^-e = d[-1]
+//      (10 * p2) mod 2^-e = d[-2] / 10^1 + ...
+//
+// The multiplication by 10 must not overflow. It is sufficient to choose
+//
+//      10 * p2 < 16 * p2 = 2^4 * p2 <= 2^64.
+//
+// Since p2 = f mod 2^-e < 2^-e,
+//
+//      -e <= 60   or   e >= -60 := alpha
+
+constexpr int kAlpha = -60;
+constexpr int kGamma = -32;
+
+struct cached_power // c = f * 2^e ~= 10^k
+{
+    uint64_t f;
+    int e;
+    int k;
+};
+
+/*!
+For a normalized diyfp w = f * 2^e, this function returns a (normalized) cached
+power-of-ten c = f_c * 2^e_c, such that the exponent of the product w * c
+satisfies (Definition 3.2 from [1])
+
+     alpha <= e_c + e + q <= gamma.
+*/
+inline cached_power get_cached_power_for_binary_exponent(int e)
+{
+    // Now
+    //
+    //      alpha <= e_c + e + q <= gamma                                    (1)
+    //      ==> f_c * 2^alpha <= c * 2^e * 2^q
+    //
+    // and since the c's are normalized, 2^(q-1) <= f_c,
+    //
+    //      ==> 2^(q - 1 + alpha) <= c * 2^(e + q)
+    //      ==> 2^(alpha - e - 1) <= c
+    //
+    // If c were an exakt power of ten, i.e. c = 10^k, one may determine k as
+    //
+    //      k = ceil( log_10( 2^(alpha - e - 1) ) )
+    //        = ceil( (alpha - e - 1) * log_10(2) )
+    //
+    // From the paper:
+    // "In theory the result of the procedure could be wrong since c is rounded,
+    //  and the computation itself is approximated [...]. In practice, however,
+    //  this simple function is sufficient."
+    //
+    // For IEEE double precision floating-point numbers converted into
+    // normalized diyfp's w = f * 2^e, with q = 64,
+    //
+    //      e >= -1022      (min IEEE exponent)
+    //           -52        (p - 1)
+    //           -52        (p - 1, possibly normalize denormal IEEE numbers)
+    //           -11        (normalize the diyfp)
+    //         = -1137
+    //
+    // and
+    //
+    //      e <= +1023      (max IEEE exponent)
+    //           -52        (p - 1)
+    //           -11        (normalize the diyfp)
+    //         = 960
+    //
+    // This binary exponent range [-1137,960] results in a decimal exponent
+    // range [-307,324]. One does not need to store a cached power for each
+    // k in this range. For each such k it suffices to find a cached power
+    // such that the exponent of the product lies in [alpha,gamma].
+    // This implies that the difference of the decimal exponents of adjacent
+    // table entries must be less than or equal to
+    //
+    //      floor( (gamma - alpha) * log_10(2) ) = 8.
+    //
+    // (A smaller distance gamma-alpha would require a larger table.)
+
+    // NB:
+    // Actually this function returns c, such that -60 <= e_c + e + 64 <= -34.
+
+    constexpr int kCachedPowersSize = 79;
+    constexpr int kCachedPowersMinDecExp = -300;
+    constexpr int kCachedPowersDecStep = 8;
+
+    static constexpr cached_power kCachedPowers[] =
+    {
+        { 0xAB70FE17C79AC6CA, -1060, -300 },
+        { 0xFF77B1FCBEBCDC4F, -1034, -292 },
+        { 0xBE5691EF416BD60C, -1007, -284 },
+        { 0x8DD01FAD907FFC3C,  -980, -276 },
+        { 0xD3515C2831559A83,  -954, -268 },
+        { 0x9D71AC8FADA6C9B5,  -927, -260 },
+        { 0xEA9C227723EE8BCB,  -901, -252 },
+        { 0xAECC49914078536D,  -874, -244 },
+        { 0x823C12795DB6CE57,  -847, -236 },
+        { 0xC21094364DFB5637,  -821, -228 },
+        { 0x9096EA6F3848984F,  -794, -220 },
+        { 0xD77485CB25823AC7,  -768, -212 },
+        { 0xA086CFCD97BF97F4,  -741, -204 },
+        { 0xEF340A98172AACE5,  -715, -196 },
+        { 0xB23867FB2A35B28E,  -688, -188 },
+        { 0x84C8D4DFD2C63F3B,  -661, -180 },
+        { 0xC5DD44271AD3CDBA,  -635, -172 },
+        { 0x936B9FCEBB25C996,  -608, -164 },
+        { 0xDBAC6C247D62A584,  -582, -156 },
+        { 0xA3AB66580D5FDAF6,  -555, -148 },
+        { 0xF3E2F893DEC3F126,  -529, -140 },
+        { 0xB5B5ADA8AAFF80B8,  -502, -132 },
+        { 0x87625F056C7C4A8B,  -475, -124 },
+        { 0xC9BCFF6034C13053,  -449, -116 },
+        { 0x964E858C91BA2655,  -422, -108 },
+        { 0xDFF9772470297EBD,  -396, -100 },
+        { 0xA6DFBD9FB8E5B88F,  -369,  -92 },
+        { 0xF8A95FCF88747D94,  -343,  -84 },
+        { 0xB94470938FA89BCF,  -316,  -76 },
+        { 0x8A08F0F8BF0F156B,  -289,  -68 },
+        { 0xCDB02555653131B6,  -263,  -60 },
+        { 0x993FE2C6D07B7FAC,  -236,  -52 },
+        { 0xE45C10C42A2B3B06,  -210,  -44 },
+        { 0xAA242499697392D3,  -183,  -36 },
+        { 0xFD87B5F28300CA0E,  -157,  -28 },
+        { 0xBCE5086492111AEB,  -130,  -20 },
+        { 0x8CBCCC096F5088CC,  -103,  -12 },
+        { 0xD1B71758E219652C,   -77,   -4 },
+        { 0x9C40000000000000,   -50,    4 },
+        { 0xE8D4A51000000000,   -24,   12 },
+        { 0xAD78EBC5AC620000,     3,   20 },
+        { 0x813F3978F8940984,    30,   28 },
+        { 0xC097CE7BC90715B3,    56,   36 },
+        { 0x8F7E32CE7BEA5C70,    83,   44 },
+        { 0xD5D238A4ABE98068,   109,   52 },
+        { 0x9F4F2726179A2245,   136,   60 },
+        { 0xED63A231D4C4FB27,   162,   68 },
+        { 0xB0DE65388CC8ADA8,   189,   76 },
+        { 0x83C7088E1AAB65DB,   216,   84 },
+        { 0xC45D1DF942711D9A,   242,   92 },
+        { 0x924D692CA61BE758,   269,  100 },
+        { 0xDA01EE641A708DEA,   295,  108 },
+        { 0xA26DA3999AEF774A,   322,  116 },
+        { 0xF209787BB47D6B85,   348,  124 },
+        { 0xB454E4A179DD1877,   375,  132 },
+        { 0x865B86925B9BC5C2,   402,  140 },
+        { 0xC83553C5C8965D3D,   428,  148 },
+        { 0x952AB45CFA97A0B3,   455,  156 },
+        { 0xDE469FBD99A05FE3,   481,  164 },
+        { 0xA59BC234DB398C25,   508,  172 },
+        { 0xF6C69A72A3989F5C,   534,  180 },
+        { 0xB7DCBF5354E9BECE,   561,  188 },
+        { 0x88FCF317F22241E2,   588,  196 },
+        { 0xCC20CE9BD35C78A5,   614,  204 },
+        { 0x98165AF37B2153DF,   641,  212 },
+        { 0xE2A0B5DC971F303A,   667,  220 },
+        { 0xA8D9D1535CE3B396,   694,  228 },
+        { 0xFB9B7CD9A4A7443C,   720,  236 },
+        { 0xBB764C4CA7A44410,   747,  244 },
+        { 0x8BAB8EEFB6409C1A,   774,  252 },
+        { 0xD01FEF10A657842C,   800,  260 },
+        { 0x9B10A4E5E9913129,   827,  268 },
+        { 0xE7109BFBA19C0C9D,   853,  276 },
+        { 0xAC2820D9623BF429,   880,  284 },
+        { 0x80444B5E7AA7CF85,   907,  292 },
+        { 0xBF21E44003ACDD2D,   933,  300 },
+        { 0x8E679C2F5E44FF8F,   960,  308 },
+        { 0xD433179D9C8CB841,   986,  316 },
+        { 0x9E19DB92B4E31BA9,  1013,  324 },
+    };
+
+    // This computation gives exactly the same results for k as
+    //      k = ceil((kAlpha - e - 1) * 0.30102999566398114)
+    // for |e| <= 1500, but doesn't require floating-point operations.
+    // NB: log_10(2) ~= 78913 / 2^18
+    assert(e >= -1500);
+    assert(e <=  1500);
+    const int f = kAlpha - e - 1;
+    const int k = (f * 78913) / (1 << 18) + static_cast<int>(f > 0);
+
+    const int index = (-kCachedPowersMinDecExp + k + (kCachedPowersDecStep - 1)) / kCachedPowersDecStep;
+    assert(index >= 0);
+    assert(index < kCachedPowersSize);
+    static_cast<void>(kCachedPowersSize); // Fix warning.
+
+    const cached_power cached = kCachedPowers[index];
+    assert(kAlpha <= cached.e + e + 64);
+    assert(kGamma >= cached.e + e + 64);
+
+    return cached;
+}
+
+/*!
+For n != 0, returns k, such that pow10 := 10^(k-1) <= n < 10^k.
+For n == 0, returns 1 and sets pow10 := 1.
+*/
+inline int find_largest_pow10(const uint32_t n, uint32_t& pow10)
+{
+    // LCOV_EXCL_START
+    if (n >= 1000000000)
+    {
+        pow10 = 1000000000;
+        return 10;
+    }
+    // LCOV_EXCL_STOP
+    else if (n >= 100000000)
+    {
+        pow10 = 100000000;
+        return  9;
+    }
+    else if (n >= 10000000)
+    {
+        pow10 = 10000000;
+        return  8;
+    }
+    else if (n >= 1000000)
+    {
+        pow10 = 1000000;
+        return  7;
+    }
+    else if (n >= 100000)
+    {
+        pow10 = 100000;
+        return  6;
+    }
+    else if (n >= 10000)
+    {
+        pow10 = 10000;
+        return  5;
+    }
+    else if (n >= 1000)
+    {
+        pow10 = 1000;
+        return  4;
+    }
+    else if (n >= 100)
+    {
+        pow10 = 100;
+        return  3;
+    }
+    else if (n >= 10)
+    {
+        pow10 = 10;
+        return  2;
+    }
+    else
+    {
+        pow10 = 1;
+        return 1;
+    }
+}
+
+inline void grisu2_round(char* buf, int len, uint64_t dist, uint64_t delta,
+                         uint64_t rest, uint64_t ten_k)
+{
+    assert(len >= 1);
+    assert(dist <= delta);
+    assert(rest <= delta);
+    assert(ten_k > 0);
+
+    //               <--------------------------- delta ---->
+    //                                  <---- dist --------->
+    // --------------[------------------+-------------------]--------------
+    //               M-                 w                   M+
+    //
+    //                                  ten_k
+    //                                <------>
+    //                                       <---- rest ---->
+    // --------------[------------------+----+--------------]--------------
+    //                                  w    V
+    //                                       = buf * 10^k
+    //
+    // ten_k represents a unit-in-the-last-place in the decimal representation
+    // stored in buf.
+    // Decrement buf by ten_k while this takes buf closer to w.
+
+    // The tests are written in this order to avoid overflow in unsigned
+    // integer arithmetic.
+
+    while (rest < dist
+            and delta - rest >= ten_k
+            and (rest + ten_k < dist or dist - rest > rest + ten_k - dist))
+    {
+        assert(buf[len - 1] != '0');
+        buf[len - 1]--;
+        rest += ten_k;
+    }
+}
+
+/*!
+Generates V = buffer * 10^decimal_exponent, such that M- <= V <= M+.
+M- and M+ must be normalized and share the same exponent -60 <= e <= -32.
+*/
+inline void grisu2_digit_gen(char* buffer, int& length, int& decimal_exponent,
+                             diyfp M_minus, diyfp w, diyfp M_plus)
+{
+    static_assert(kAlpha >= -60, "internal error");
+    static_assert(kGamma <= -32, "internal error");
+
+    // Generates the digits (and the exponent) of a decimal floating-point
+    // number V = buffer * 10^decimal_exponent in the range [M-, M+]. The diyfp's
+    // w, M- and M+ share the same exponent e, which satisfies alpha <= e <= gamma.
+    //
+    //               <--------------------------- delta ---->
+    //                                  <---- dist --------->
+    // --------------[------------------+-------------------]--------------
+    //               M-                 w                   M+
+    //
+    // Grisu2 generates the digits of M+ from left to right and stops as soon as
+    // V is in [M-,M+].
+
+    assert(M_plus.e >= kAlpha);
+    assert(M_plus.e <= kGamma);
+
+    uint64_t delta = diyfp::sub(M_plus, M_minus).f; // (significand of (M+ - M-), implicit exponent is e)
+    uint64_t dist  = diyfp::sub(M_plus, w      ).f; // (significand of (M+ - w ), implicit exponent is e)
+
+    // Split M+ = f * 2^e into two parts p1 and p2 (note: e < 0):
+    //
+    //      M+ = f * 2^e
+    //         = ((f div 2^-e) * 2^-e + (f mod 2^-e)) * 2^e
+    //         = ((p1        ) * 2^-e + (p2        )) * 2^e
+    //         = p1 + p2 * 2^e
+
+    const diyfp one(uint64_t{1} << -M_plus.e, M_plus.e);
+
+    auto p1 = static_cast<uint32_t>(M_plus.f >> -one.e); // p1 = f div 2^-e (Since -e >= 32, p1 fits into a 32-bit int.)
+    uint64_t p2 = M_plus.f & (one.f - 1);                    // p2 = f mod 2^-e
+
+    // 1)
+    //
+    // Generate the digits of the integral part p1 = d[n-1]...d[1]d[0]
+
+    assert(p1 > 0);
+
+    uint32_t pow10;
+    const int k = find_largest_pow10(p1, pow10);
+
+    //      10^(k-1) <= p1 < 10^k, pow10 = 10^(k-1)
+    //
+    //      p1 = (p1 div 10^(k-1)) * 10^(k-1) + (p1 mod 10^(k-1))
+    //         = (d[k-1]         ) * 10^(k-1) + (p1 mod 10^(k-1))
+    //
+    //      M+ = p1                                             + p2 * 2^e
+    //         = d[k-1] * 10^(k-1) + (p1 mod 10^(k-1))          + p2 * 2^e
+    //         = d[k-1] * 10^(k-1) + ((p1 mod 10^(k-1)) * 2^-e + p2) * 2^e
+    //         = d[k-1] * 10^(k-1) + (                         rest) * 2^e
+    //
+    // Now generate the digits d[n] of p1 from left to right (n = k-1,...,0)
+    //
+    //      p1 = d[k-1]...d[n] * 10^n + d[n-1]...d[0]
+    //
+    // but stop as soon as
+    //
+    //      rest * 2^e = (d[n-1]...d[0] * 2^-e + p2) * 2^e <= delta * 2^e
+
+    int n = k;
+    while (n > 0)
+    {
+        // Invariants:
+        //      M+ = buffer * 10^n + (p1 + p2 * 2^e)    (buffer = 0 for n = k)
+        //      pow10 = 10^(n-1) <= p1 < 10^n
+        //
+        const uint32_t d = p1 / pow10;  // d = p1 div 10^(n-1)
+        const uint32_t r = p1 % pow10;  // r = p1 mod 10^(n-1)
+        //
+        //      M+ = buffer * 10^n + (d * 10^(n-1) + r) + p2 * 2^e
+        //         = (buffer * 10 + d) * 10^(n-1) + (r + p2 * 2^e)
+        //
+        assert(d <= 9);
+        buffer[length++] = static_cast<char>('0' + d); // buffer := buffer * 10 + d
+        //
+        //      M+ = buffer * 10^(n-1) + (r + p2 * 2^e)
+        //
+        p1 = r;
+        n--;
+        //
+        //      M+ = buffer * 10^n + (p1 + p2 * 2^e)
+        //      pow10 = 10^n
+        //
+
+        // Now check if enough digits have been generated.
+        // Compute
+        //
+        //      p1 + p2 * 2^e = (p1 * 2^-e + p2) * 2^e = rest * 2^e
+        //
+        // Note:
+        // Since rest and delta share the same exponent e, it suffices to
+        // compare the significands.
+        const uint64_t rest = (uint64_t{p1} << -one.e) + p2;
+        if (rest <= delta)
+        {
+            // V = buffer * 10^n, with M- <= V <= M+.
+
+            decimal_exponent += n;
+
+            // We may now just stop. But instead look if the buffer could be
+            // decremented to bring V closer to w.
+            //
+            // pow10 = 10^n is now 1 ulp in the decimal representation V.
+            // The rounding procedure works with diyfp's with an implicit
+            // exponent of e.
+            //
+            //      10^n = (10^n * 2^-e) * 2^e = ulp * 2^e
+            //
+            const uint64_t ten_n = uint64_t{pow10} << -one.e;
+            grisu2_round(buffer, length, dist, delta, rest, ten_n);
+
+            return;
+        }
+
+        pow10 /= 10;
+        //
+        //      pow10 = 10^(n-1) <= p1 < 10^n
+        // Invariants restored.
+    }
+
+    // 2)
+    //
+    // The digits of the integral part have been generated:
+    //
+    //      M+ = d[k-1]...d[1]d[0] + p2 * 2^e
+    //         = buffer            + p2 * 2^e
+    //
+    // Now generate the digits of the fractional part p2 * 2^e.
+    //
+    // Note:
+    // No decimal point is generated: the exponent is adjusted instead.
+    //
+    // p2 actually represents the fraction
+    //
+    //      p2 * 2^e
+    //          = p2 / 2^-e
+    //          = d[-1] / 10^1 + d[-2] / 10^2 + ...
+    //
+    // Now generate the digits d[-m] of p1 from left to right (m = 1,2,...)
+    //
+    //      p2 * 2^e = d[-1]d[-2]...d[-m] * 10^-m
+    //                      + 10^-m * (d[-m-1] / 10^1 + d[-m-2] / 10^2 + ...)
+    //
+    // using
+    //
+    //      10^m * p2 = ((10^m * p2) div 2^-e) * 2^-e + ((10^m * p2) mod 2^-e)
+    //                = (                   d) * 2^-e + (                   r)
+    //
+    // or
+    //      10^m * p2 * 2^e = d + r * 2^e
+    //
+    // i.e.
+    //
+    //      M+ = buffer + p2 * 2^e
+    //         = buffer + 10^-m * (d + r * 2^e)
+    //         = (buffer * 10^m + d) * 10^-m + 10^-m * r * 2^e
+    //
+    // and stop as soon as 10^-m * r * 2^e <= delta * 2^e
+
+    assert(p2 > delta);
+
+    int m = 0;
+    for (;;)
+    {
+        // Invariant:
+        //      M+ = buffer * 10^-m + 10^-m * (d[-m-1] / 10 + d[-m-2] / 10^2 + ...) * 2^e
+        //         = buffer * 10^-m + 10^-m * (p2                                 ) * 2^e
+        //         = buffer * 10^-m + 10^-m * (1/10 * (10 * p2)                   ) * 2^e
+        //         = buffer * 10^-m + 10^-m * (1/10 * ((10*p2 div 2^-e) * 2^-e + (10*p2 mod 2^-e)) * 2^e
+        //
+        assert(p2 <= UINT64_MAX / 10);
+        p2 *= 10;
+        const uint64_t d = p2 >> -one.e;     // d = (10 * p2) div 2^-e
+        const uint64_t r = p2 & (one.f - 1); // r = (10 * p2) mod 2^-e
+        //
+        //      M+ = buffer * 10^-m + 10^-m * (1/10 * (d * 2^-e + r) * 2^e
+        //         = buffer * 10^-m + 10^-m * (1/10 * (d + r * 2^e))
+        //         = (buffer * 10 + d) * 10^(-m-1) + 10^(-m-1) * r * 2^e
+        //
+        assert(d <= 9);
+        buffer[length++] = static_cast<char>('0' + d); // buffer := buffer * 10 + d
+        //
+        //      M+ = buffer * 10^(-m-1) + 10^(-m-1) * r * 2^e
+        //
+        p2 = r;
+        m++;
+        //
+        //      M+ = buffer * 10^-m + 10^-m * p2 * 2^e
+        // Invariant restored.
+
+        // Check if enough digits have been generated.
+        //
+        //      10^-m * p2 * 2^e <= delta * 2^e
+        //              p2 * 2^e <= 10^m * delta * 2^e
+        //                    p2 <= 10^m * delta
+        delta *= 10;
+        dist  *= 10;
+        if (p2 <= delta)
+        {
+            break;
+        }
+    }
+
+    // V = buffer * 10^-m, with M- <= V <= M+.
+
+    decimal_exponent -= m;
+
+    // 1 ulp in the decimal representation is now 10^-m.
+    // Since delta and dist are now scaled by 10^m, we need to do the
+    // same with ulp in order to keep the units in sync.
+    //
+    //      10^m * 10^-m = 1 = 2^-e * 2^e = ten_m * 2^e
+    //
+    const uint64_t ten_m = one.f;
+    grisu2_round(buffer, length, dist, delta, p2, ten_m);
+
+    // By construction this algorithm generates the shortest possible decimal
+    // number (Loitsch, Theorem 6.2) which rounds back to w.
+    // For an input number of precision p, at least
+    //
+    //      N = 1 + ceil(p * log_10(2))
+    //
+    // decimal digits are sufficient to identify all binary floating-point
+    // numbers (Matula, "In-and-Out conversions").
+    // This implies that the algorithm does not produce more than N decimal
+    // digits.
+    //
+    //      N = 17 for p = 53 (IEEE double precision)
+    //      N = 9  for p = 24 (IEEE single precision)
+}
+
+/*!
+v = buf * 10^decimal_exponent
+len is the length of the buffer (number of decimal digits)
+The buffer must be large enough, i.e. >= max_digits10.
+*/
+inline void grisu2(char* buf, int& len, int& decimal_exponent,
+                   diyfp m_minus, diyfp v, diyfp m_plus)
+{
+    assert(m_plus.e == m_minus.e);
+    assert(m_plus.e == v.e);
+
+    //  --------(-----------------------+-----------------------)--------    (A)
+    //          m-                      v                       m+
+    //
+    //  --------------------(-----------+-----------------------)--------    (B)
+    //                      m-          v                       m+
+    //
+    // First scale v (and m- and m+) such that the exponent is in the range
+    // [alpha, gamma].
+
+    const cached_power cached = get_cached_power_for_binary_exponent(m_plus.e);
+
+    const diyfp c_minus_k(cached.f, cached.e); // = c ~= 10^-k
+
+    // The exponent of the products is = v.e + c_minus_k.e + q and is in the range [alpha,gamma]
+    const diyfp w       = diyfp::mul(v,       c_minus_k);
+    const diyfp w_minus = diyfp::mul(m_minus, c_minus_k);
+    const diyfp w_plus  = diyfp::mul(m_plus,  c_minus_k);
+
+    //  ----(---+---)---------------(---+---)---------------(---+---)----
+    //          w-                      w                       w+
+    //          = c*m-                  = c*v                   = c*m+
+    //
+    // diyfp::mul rounds its result and c_minus_k is approximated too. w, w- and
+    // w+ are now off by a small amount.
+    // In fact:
+    //
+    //      w - v * 10^k < 1 ulp
+    //
+    // To account for this inaccuracy, add resp. subtract 1 ulp.
+    //
+    //  --------+---[---------------(---+---)---------------]---+--------
+    //          w-  M-                  w                   M+  w+
+    //
+    // Now any number in [M-, M+] (bounds included) will round to w when input,
+    // regardless of how the input rounding algorithm breaks ties.
+    //
+    // And digit_gen generates the shortest possible such number in [M-, M+].
+    // Note that this does not mean that Grisu2 always generates the shortest
+    // possible number in the interval (m-, m+).
+    const diyfp M_minus(w_minus.f + 1, w_minus.e);
+    const diyfp M_plus (w_plus.f  - 1, w_plus.e );
+
+    decimal_exponent = -cached.k; // = -(-k) = k
+
+    grisu2_digit_gen(buf, len, decimal_exponent, M_minus, w, M_plus);
+}
+
+/*!
+v = buf * 10^decimal_exponent
+len is the length of the buffer (number of decimal digits)
+The buffer must be large enough, i.e. >= max_digits10.
+*/
+template <typename FloatType>
+void grisu2(char* buf, int& len, int& decimal_exponent, FloatType value)
+{
+    static_assert(diyfp::kPrecision >= std::numeric_limits<FloatType>::digits + 3,
+                  "internal error: not enough precision");
+
+    assert(std::isfinite(value));
+    assert(value > 0);
+
+    // If the neighbors (and boundaries) of 'value' are always computed for double-precision
+    // numbers, all float's can be recovered using strtod (and strtof). However, the resulting
+    // decimal representations are not exactly "short".
+    //
+    // The documentation for 'std::to_chars' (https://en.cppreference.com/w/cpp/utility/to_chars)
+    // says "value is converted to a string as if by std::sprintf in the default ("C") locale"
+    // and since sprintf promotes float's to double's, I think this is exactly what 'std::to_chars'
+    // does.
+    // On the other hand, the documentation for 'std::to_chars' requires that "parsing the
+    // representation using the corresponding std::from_chars function recovers value exactly". That
+    // indicates that single precision floating-point numbers should be recovered using
+    // 'std::strtof'.
+    //
+    // NB: If the neighbors are computed for single-precision numbers, there is a single float
+    //     (7.0385307e-26f) which can't be recovered using strtod. The resulting double precision
+    //     value is off by 1 ulp.
+#if 0
+    const boundaries w = compute_boundaries(static_cast<double>(value));
+#else
+    const boundaries w = compute_boundaries(value);
+#endif
+
+    grisu2(buf, len, decimal_exponent, w.minus, w.w, w.plus);
+}
+
+/*!
+@brief appends a decimal representation of e to buf
+@return a pointer to the element following the exponent.
+@pre -1000 < e < 1000
+*/
+inline char* append_exponent(char* buf, int e)
+{
+    assert(e > -1000);
+    assert(e <  1000);
+
+    if (e < 0)
+    {
+        e = -e;
+        *buf++ = '-';
+    }
+    else
+    {
+        *buf++ = '+';
+    }
+
+    auto k = static_cast<uint32_t>(e);
+    if (k < 10)
+    {
+        // Always print at least two digits in the exponent.
+        // This is for compatibility with printf("%g").
+        *buf++ = '0';
+        *buf++ = static_cast<char>('0' + k);
+    }
+    else if (k < 100)
+    {
+        *buf++ = static_cast<char>('0' + k / 10);
+        k %= 10;
+        *buf++ = static_cast<char>('0' + k);
+    }
+    else
+    {
+        *buf++ = static_cast<char>('0' + k / 100);
+        k %= 100;
+        *buf++ = static_cast<char>('0' + k / 10);
+        k %= 10;
+        *buf++ = static_cast<char>('0' + k);
+    }
+
+    return buf;
+}
+
+/*!
+@brief prettify v = buf * 10^decimal_exponent
+
+If v is in the range [10^min_exp, 10^max_exp) it will be printed in fixed-point
+notation. Otherwise it will be printed in exponential notation.
+
+@pre min_exp < 0
+@pre max_exp > 0
+*/
+inline char* format_buffer(char* buf, int len, int decimal_exponent,
+                           int min_exp, int max_exp)
+{
+    assert(min_exp < 0);
+    assert(max_exp > 0);
+
+    const int k = len;
+    const int n = len + decimal_exponent;
+
+    // v = buf * 10^(n-k)
+    // k is the length of the buffer (number of decimal digits)
+    // n is the position of the decimal point relative to the start of the buffer.
+
+    if (k <= n and n <= max_exp)
+    {
+        // digits[000]
+        // len <= max_exp + 2
+
+        std::memset(buf + k, '0', static_cast<size_t>(n - k));
+        // Make it look like a floating-point number (#362, #378)
+        buf[n + 0] = '.';
+        buf[n + 1] = '0';
+        return buf + (n + 2);
+    }
+
+    if (0 < n and n <= max_exp)
+    {
+        // dig.its
+        // len <= max_digits10 + 1
+
+        assert(k > n);
+
+        std::memmove(buf + (n + 1), buf + n, static_cast<size_t>(k - n));
+        buf[n] = '.';
+        return buf + (k + 1);
+    }
+
+    if (min_exp < n and n <= 0)
+    {
+        // 0.[000]digits
+        // len <= 2 + (-min_exp - 1) + max_digits10
+
+        std::memmove(buf + (2 + -n), buf, static_cast<size_t>(k));
+        buf[0] = '0';
+        buf[1] = '.';
+        std::memset(buf + 2, '0', static_cast<size_t>(-n));
+        return buf + (2 + (-n) + k);
+    }
+
+    if (k == 1)
+    {
+        // dE+123
+        // len <= 1 + 5
+
+        buf += 1;
+    }
+    else
+    {
+        // d.igitsE+123
+        // len <= max_digits10 + 1 + 5
+
+        std::memmove(buf + 2, buf + 1, static_cast<size_t>(k - 1));
+        buf[1] = '.';
+        buf += 1 + k;
+    }
+
+    *buf++ = 'e';
+    return append_exponent(buf, n - 1);
+}
+
+} // namespace dtoa_impl
+
+/*!
+@brief generates a decimal representation of the floating-point number value in [first, last).
+
+The format of the resulting decimal representation is similar to printf's %g
+format. Returns an iterator pointing past-the-end of the decimal representation.
+
+@note The input number must be finite, i.e. NaN's and Inf's are not supported.
+@note The buffer must be large enough.
+@note The result is NOT null-terminated.
+*/
+template <typename FloatType>
+char* to_chars(char* first, const char* last, FloatType value)
+{
+    static_cast<void>(last); // maybe unused - fix warning
+    assert(std::isfinite(value));
+
+    // Use signbit(value) instead of (value < 0) since signbit works for -0.
+    if (std::signbit(value))
+    {
+        value = -value;
+        *first++ = '-';
+    }
+
+    if (value == 0) // +-0
+    {
+        *first++ = '0';
+        // Make it look like a floating-point number (#362, #378)
+        *first++ = '.';
+        *first++ = '0';
+        return first;
+    }
+
+    assert(last - first >= std::numeric_limits<FloatType>::max_digits10);
+
+    // Compute v = buffer * 10^decimal_exponent.
+    // The decimal digits are stored in the buffer, which needs to be interpreted
+    // as an unsigned decimal integer.
+    // len is the length of the buffer, i.e. the number of decimal digits.
+    int len = 0;
+    int decimal_exponent = 0;
+    dtoa_impl::grisu2(first, len, decimal_exponent, value);
+
+    assert(len <= std::numeric_limits<FloatType>::max_digits10);
+
+    // Format the buffer like printf("%.*g", prec, value)
+    constexpr int kMinExp = -4;
+    // Use digits10 here to increase compatibility with version 2.
+    constexpr int kMaxExp = std::numeric_limits<FloatType>::digits10;
+
+    assert(last - first >= kMaxExp + 2);
+    assert(last - first >= 2 + (-kMinExp - 1) + std::numeric_limits<FloatType>::max_digits10);
+    assert(last - first >= std::numeric_limits<FloatType>::max_digits10 + 6);
+
+    return dtoa_impl::format_buffer(first, len, decimal_exponent, kMinExp, kMaxExp);
+}
+
+} // namespace detail
+} // namespace nlohmann
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/meta/cpp_future.hpp>
+
+// #include <nlohmann/detail/output/binary_writer.hpp>
+
+// #include <nlohmann/detail/output/output_adapters.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+///////////////////
+// serialization //
+///////////////////
+
+/// how to treat decoding errors
+enum class error_handler_t
+{
+    strict,  ///< throw a type_error exception in case of invalid UTF-8
+    replace, ///< replace invalid UTF-8 sequences with U+FFFD
+    ignore   ///< ignore invalid UTF-8 sequences
+};
+
+template<typename BasicJsonType>
+class serializer
+{
+    using string_t = typename BasicJsonType::string_t;
+    using number_float_t = typename BasicJsonType::number_float_t;
+    using number_integer_t = typename BasicJsonType::number_integer_t;
+    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+    static constexpr uint8_t UTF8_ACCEPT = 0;
+    static constexpr uint8_t UTF8_REJECT = 1;
+
+  public:
+    /*!
+    @param[in] s  output stream to serialize to
+    @param[in] ichar  indentation character to use
+    @param[in] error_handler_  how to react on decoding errors
+    */
+    serializer(output_adapter_t<char> s, const char ichar,
+               error_handler_t error_handler_ = error_handler_t::strict)
+        : o(std::move(s))
+        , loc(std::localeconv())
+        , thousands_sep(loc->thousands_sep == nullptr ? '\0' : * (loc->thousands_sep))
+        , decimal_point(loc->decimal_point == nullptr ? '\0' : * (loc->decimal_point))
+        , indent_char(ichar)
+        , indent_string(512, indent_char)
+        , error_handler(error_handler_)
+    {}
+
+    // delete because of pointer members
+    serializer(const serializer&) = delete;
+    serializer& operator=(const serializer&) = delete;
+    serializer(serializer&&) = delete;
+    serializer& operator=(serializer&&) = delete;
+    ~serializer() = default;
+
+    /*!
+    @brief internal implementation of the serialization function
+
+    This function is called by the public member function dump and organizes
+    the serialization internally. The indentation level is propagated as
+    additional parameter. In case of arrays and objects, the function is
+    called recursively.
+
+    - strings and object keys are escaped using `escape_string()`
+    - integer numbers are converted implicitly via `operator<<`
+    - floating-point numbers are converted to a string using `"%g"` format
+
+    @param[in] val             value to serialize
+    @param[in] pretty_print    whether the output shall be pretty-printed
+    @param[in] indent_step     the indent level
+    @param[in] current_indent  the current indent level (only used internally)
+    */
+    void dump(const BasicJsonType& val, const bool pretty_print,
+              const bool ensure_ascii,
+              const unsigned int indent_step,
+              const unsigned int current_indent = 0)
+    {
+        switch (val.m_type)
+        {
+            case value_t::object:
+            {
+                if (val.m_value.object->empty())
+                {
+                    o->write_characters("{}", 2);
+                    return;
+                }
+
+                if (pretty_print)
+                {
+                    o->write_characters("{\n", 2);
+
+                    // variable to hold indentation for recursive calls
+                    const auto new_indent = current_indent + indent_step;
+                    if (JSON_UNLIKELY(indent_string.size() < new_indent))
+                    {
+                        indent_string.resize(indent_string.size() * 2, ' ');
+                    }
+
+                    // first n-1 elements
+                    auto i = val.m_value.object->cbegin();
+                    for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i)
+                    {
+                        o->write_characters(indent_string.c_str(), new_indent);
+                        o->write_character('\"');
+                        dump_escaped(i->first, ensure_ascii);
+                        o->write_characters("\": ", 3);
+                        dump(i->second, true, ensure_ascii, indent_step, new_indent);
+                        o->write_characters(",\n", 2);
+                    }
+
+                    // last element
+                    assert(i != val.m_value.object->cend());
+                    assert(std::next(i) == val.m_value.object->cend());
+                    o->write_characters(indent_string.c_str(), new_indent);
+                    o->write_character('\"');
+                    dump_escaped(i->first, ensure_ascii);
+                    o->write_characters("\": ", 3);
+                    dump(i->second, true, ensure_ascii, indent_step, new_indent);
+
+                    o->write_character('\n');
+                    o->write_characters(indent_string.c_str(), current_indent);
+                    o->write_character('}');
+                }
+                else
+                {
+                    o->write_character('{');
+
+                    // first n-1 elements
+                    auto i = val.m_value.object->cbegin();
+                    for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i)
+                    {
+                        o->write_character('\"');
+                        dump_escaped(i->first, ensure_ascii);
+                        o->write_characters("\":", 2);
+                        dump(i->second, false, ensure_ascii, indent_step, current_indent);
+                        o->write_character(',');
+                    }
+
+                    // last element
+                    assert(i != val.m_value.object->cend());
+                    assert(std::next(i) == val.m_value.object->cend());
+                    o->write_character('\"');
+                    dump_escaped(i->first, ensure_ascii);
+                    o->write_characters("\":", 2);
+                    dump(i->second, false, ensure_ascii, indent_step, current_indent);
+
+                    o->write_character('}');
+                }
+
+                return;
+            }
+
+            case value_t::array:
+            {
+                if (val.m_value.array->empty())
+                {
+                    o->write_characters("[]", 2);
+                    return;
+                }
+
+                if (pretty_print)
+                {
+                    o->write_characters("[\n", 2);
+
+                    // variable to hold indentation for recursive calls
+                    const auto new_indent = current_indent + indent_step;
+                    if (JSON_UNLIKELY(indent_string.size() < new_indent))
+                    {
+                        indent_string.resize(indent_string.size() * 2, ' ');
+                    }
+
+                    // first n-1 elements
+                    for (auto i = val.m_value.array->cbegin();
+                            i != val.m_value.array->cend() - 1; ++i)
+                    {
+                        o->write_characters(indent_string.c_str(), new_indent);
+                        dump(*i, true, ensure_ascii, indent_step, new_indent);
+                        o->write_characters(",\n", 2);
+                    }
+
+                    // last element
+                    assert(not val.m_value.array->empty());
+                    o->write_characters(indent_string.c_str(), new_indent);
+                    dump(val.m_value.array->back(), true, ensure_ascii, indent_step, new_indent);
+
+                    o->write_character('\n');
+                    o->write_characters(indent_string.c_str(), current_indent);
+                    o->write_character(']');
+                }
+                else
+                {
+                    o->write_character('[');
+
+                    // first n-1 elements
+                    for (auto i = val.m_value.array->cbegin();
+                            i != val.m_value.array->cend() - 1; ++i)
+                    {
+                        dump(*i, false, ensure_ascii, indent_step, current_indent);
+                        o->write_character(',');
+                    }
+
+                    // last element
+                    assert(not val.m_value.array->empty());
+                    dump(val.m_value.array->back(), false, ensure_ascii, indent_step, current_indent);
+
+                    o->write_character(']');
+                }
+
+                return;
+            }
+
+            case value_t::string:
+            {
+                o->write_character('\"');
+                dump_escaped(*val.m_value.string, ensure_ascii);
+                o->write_character('\"');
+                return;
+            }
+
+            case value_t::boolean:
+            {
+                if (val.m_value.boolean)
+                {
+                    o->write_characters("true", 4);
+                }
+                else
+                {
+                    o->write_characters("false", 5);
+                }
+                return;
+            }
+
+            case value_t::number_integer:
+            {
+                dump_integer(val.m_value.number_integer);
+                return;
+            }
+
+            case value_t::number_unsigned:
+            {
+                dump_integer(val.m_value.number_unsigned);
+                return;
+            }
+
+            case value_t::number_float:
+            {
+                dump_float(val.m_value.number_float);
+                return;
+            }
+
+            case value_t::discarded:
+            {
+                o->write_characters("<discarded>", 11);
+                return;
+            }
+
+            case value_t::null:
+            {
+                o->write_characters("null", 4);
+                return;
+            }
+        }
+    }
+
+  private:
+    /*!
+    @brief dump escaped string
+
+    Escape a string by replacing certain special characters by a sequence of an
+    escape character (backslash) and another character and other control
+    characters by a sequence of "\u" followed by a four-digit hex
+    representation. The escaped string is written to output stream @a o.
+
+    @param[in] s  the string to escape
+    @param[in] ensure_ascii  whether to escape non-ASCII characters with
+                             \uXXXX sequences
+
+    @complexity Linear in the length of string @a s.
+    */
+    void dump_escaped(const string_t& s, const bool ensure_ascii)
+    {
+        uint32_t codepoint;
+        uint8_t state = UTF8_ACCEPT;
+        std::size_t bytes = 0;  // number of bytes written to string_buffer
+
+        // number of bytes written at the point of the last valid byte
+        std::size_t bytes_after_last_accept = 0;
+        std::size_t undumped_chars = 0;
+
+        for (std::size_t i = 0; i < s.size(); ++i)
+        {
+            const auto byte = static_cast<uint8_t>(s[i]);
+
+            switch (decode(state, codepoint, byte))
+            {
+                case UTF8_ACCEPT:  // decode found a new code point
+                {
+                    switch (codepoint)
+                    {
+                        case 0x08: // backspace
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = 'b';
+                            break;
+                        }
+
+                        case 0x09: // horizontal tab
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = 't';
+                            break;
+                        }
+
+                        case 0x0A: // newline
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = 'n';
+                            break;
+                        }
+
+                        case 0x0C: // formfeed
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = 'f';
+                            break;
+                        }
+
+                        case 0x0D: // carriage return
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = 'r';
+                            break;
+                        }
+
+                        case 0x22: // quotation mark
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = '\"';
+                            break;
+                        }
+
+                        case 0x5C: // reverse solidus
+                        {
+                            string_buffer[bytes++] = '\\';
+                            string_buffer[bytes++] = '\\';
+                            break;
+                        }
+
+                        default:
+                        {
+                            // escape control characters (0x00..0x1F) or, if
+                            // ensure_ascii parameter is used, non-ASCII characters
+                            if ((codepoint <= 0x1F) or (ensure_ascii and (codepoint >= 0x7F)))
+                            {
+                                if (codepoint <= 0xFFFF)
+                                {
+                                    (std::snprintf)(string_buffer.data() + bytes, 7, "\\u%04x",
+                                                    static_cast<uint16_t>(codepoint));
+                                    bytes += 6;
+                                }
+                                else
+                                {
+                                    (std::snprintf)(string_buffer.data() + bytes, 13, "\\u%04x\\u%04x",
+                                                    static_cast<uint16_t>(0xD7C0 + (codepoint >> 10)),
+                                                    static_cast<uint16_t>(0xDC00 + (codepoint & 0x3FF)));
+                                    bytes += 12;
+                                }
+                            }
+                            else
+                            {
+                                // copy byte to buffer (all previous bytes
+                                // been copied have in default case above)
+                                string_buffer[bytes++] = s[i];
+                            }
+                            break;
+                        }
+                    }
+
+                    // write buffer and reset index; there must be 13 bytes
+                    // left, as this is the maximal number of bytes to be
+                    // written ("\uxxxx\uxxxx\0") for one code point
+                    if (string_buffer.size() - bytes < 13)
+                    {
+                        o->write_characters(string_buffer.data(), bytes);
+                        bytes = 0;
+                    }
+
+                    // remember the byte position of this accept
+                    bytes_after_last_accept = bytes;
+                    undumped_chars = 0;
+                    break;
+                }
+
+                case UTF8_REJECT:  // decode found invalid UTF-8 byte
+                {
+                    switch (error_handler)
+                    {
+                        case error_handler_t::strict:
+                        {
+                            std::string sn(3, '\0');
+                            (std::snprintf)(&sn[0], sn.size(), "%.2X", byte);
+                            JSON_THROW(type_error::create(316, "invalid UTF-8 byte at index " + std::to_string(i) + ": 0x" + sn));
+                        }
+
+                        case error_handler_t::ignore:
+                        case error_handler_t::replace:
+                        {
+                            // in case we saw this character the first time, we
+                            // would like to read it again, because the byte
+                            // may be OK for itself, but just not OK for the
+                            // previous sequence
+                            if (undumped_chars > 0)
+                            {
+                                --i;
+                            }
+
+                            // reset length buffer to the last accepted index;
+                            // thus removing/ignoring the invalid characters
+                            bytes = bytes_after_last_accept;
+
+                            if (error_handler == error_handler_t::replace)
+                            {
+                                // add a replacement character
+                                if (ensure_ascii)
+                                {
+                                    string_buffer[bytes++] = '\\';
+                                    string_buffer[bytes++] = 'u';
+                                    string_buffer[bytes++] = 'f';
+                                    string_buffer[bytes++] = 'f';
+                                    string_buffer[bytes++] = 'f';
+                                    string_buffer[bytes++] = 'd';
+                                }
+                                else
+                                {
+                                    string_buffer[bytes++] = detail::binary_writer<BasicJsonType, char>::to_char_type('\xEF');
+                                    string_buffer[bytes++] = detail::binary_writer<BasicJsonType, char>::to_char_type('\xBF');
+                                    string_buffer[bytes++] = detail::binary_writer<BasicJsonType, char>::to_char_type('\xBD');
+                                }
+                                bytes_after_last_accept = bytes;
+                            }
+
+                            undumped_chars = 0;
+
+                            // continue processing the string
+                            state = UTF8_ACCEPT;
+                            break;
+                        }
+                    }
+                    break;
+                }
+
+                default:  // decode found yet incomplete multi-byte code point
+                {
+                    if (not ensure_ascii)
+                    {
+                        // code point will not be escaped - copy byte to buffer
+                        string_buffer[bytes++] = s[i];
+                    }
+                    ++undumped_chars;
+                    break;
+                }
+            }
+        }
+
+        // we finished processing the string
+        if (JSON_LIKELY(state == UTF8_ACCEPT))
+        {
+            // write buffer
+            if (bytes > 0)
+            {
+                o->write_characters(string_buffer.data(), bytes);
+            }
+        }
+        else
+        {
+            // we finish reading, but do not accept: string was incomplete
+            switch (error_handler)
+            {
+                case error_handler_t::strict:
+                {
+                    std::string sn(3, '\0');
+                    (std::snprintf)(&sn[0], sn.size(), "%.2X", static_cast<uint8_t>(s.back()));
+                    JSON_THROW(type_error::create(316, "incomplete UTF-8 string; last byte: 0x" + sn));
+                }
+
+                case error_handler_t::ignore:
+                {
+                    // write all accepted bytes
+                    o->write_characters(string_buffer.data(), bytes_after_last_accept);
+                    break;
+                }
+
+                case error_handler_t::replace:
+                {
+                    // write all accepted bytes
+                    o->write_characters(string_buffer.data(), bytes_after_last_accept);
+                    // add a replacement character
+                    if (ensure_ascii)
+                    {
+                        o->write_characters("\\ufffd", 6);
+                    }
+                    else
+                    {
+                        o->write_characters("\xEF\xBF\xBD", 3);
+                    }
+                    break;
+                }
+            }
+        }
+    }
+
+    /*!
+    @brief dump an integer
+
+    Dump a given integer to output stream @a o. Works internally with
+    @a number_buffer.
+
+    @param[in] x  integer number (signed or unsigned) to dump
+    @tparam NumberType either @a number_integer_t or @a number_unsigned_t
+    */
+    template<typename NumberType, detail::enable_if_t<
+                 std::is_same<NumberType, number_unsigned_t>::value or
+                 std::is_same<NumberType, number_integer_t>::value,
+                 int> = 0>
+    void dump_integer(NumberType x)
+    {
+        // special case for "0"
+        if (x == 0)
+        {
+            o->write_character('0');
+            return;
+        }
+
+        const bool is_negative = std::is_same<NumberType, number_integer_t>::value and not (x >= 0);  // see issue #755
+        std::size_t i = 0;
+
+        while (x != 0)
+        {
+            // spare 1 byte for '\0'
+            assert(i < number_buffer.size() - 1);
+
+            const auto digit = std::labs(static_cast<long>(x % 10));
+            number_buffer[i++] = static_cast<char>('0' + digit);
+            x /= 10;
+        }
+
+        if (is_negative)
+        {
+            // make sure there is capacity for the '-'
+            assert(i < number_buffer.size() - 2);
+            number_buffer[i++] = '-';
+        }
+
+        std::reverse(number_buffer.begin(), number_buffer.begin() + i);
+        o->write_characters(number_buffer.data(), i);
+    }
+
+    /*!
+    @brief dump a floating-point number
+
+    Dump a given floating-point number to output stream @a o. Works internally
+    with @a number_buffer.
+
+    @param[in] x  floating-point number to dump
+    */
+    void dump_float(number_float_t x)
+    {
+        // NaN / inf
+        if (not std::isfinite(x))
+        {
+            o->write_characters("null", 4);
+            return;
+        }
+
+        // If number_float_t is an IEEE-754 single or double precision number,
+        // use the Grisu2 algorithm to produce short numbers which are
+        // guaranteed to round-trip, using strtof and strtod, resp.
+        //
+        // NB: The test below works if <long double> == <double>.
+        static constexpr bool is_ieee_single_or_double
+            = (std::numeric_limits<number_float_t>::is_iec559 and std::numeric_limits<number_float_t>::digits == 24 and std::numeric_limits<number_float_t>::max_exponent == 128) or
+              (std::numeric_limits<number_float_t>::is_iec559 and std::numeric_limits<number_float_t>::digits == 53 and std::numeric_limits<number_float_t>::max_exponent == 1024);
+
+        dump_float(x, std::integral_constant<bool, is_ieee_single_or_double>());
+    }
+
+    void dump_float(number_float_t x, std::true_type /*is_ieee_single_or_double*/)
+    {
+        char* begin = number_buffer.data();
+        char* end = ::nlohmann::detail::to_chars(begin, begin + number_buffer.size(), x);
+
+        o->write_characters(begin, static_cast<size_t>(end - begin));
+    }
+
+    void dump_float(number_float_t x, std::false_type /*is_ieee_single_or_double*/)
+    {
+        // get number of digits for a float -> text -> float round-trip
+        static constexpr auto d = std::numeric_limits<number_float_t>::max_digits10;
+
+        // the actual conversion
+        std::ptrdiff_t len = (std::snprintf)(number_buffer.data(), number_buffer.size(), "%.*g", d, x);
+
+        // negative value indicates an error
+        assert(len > 0);
+        // check if buffer was large enough
+        assert(static_cast<std::size_t>(len) < number_buffer.size());
+
+        // erase thousands separator
+        if (thousands_sep != '\0')
+        {
+            const auto end = std::remove(number_buffer.begin(),
+                                         number_buffer.begin() + len, thousands_sep);
+            std::fill(end, number_buffer.end(), '\0');
+            assert((end - number_buffer.begin()) <= len);
+            len = (end - number_buffer.begin());
+        }
+
+        // convert decimal point to '.'
+        if (decimal_point != '\0' and decimal_point != '.')
+        {
+            const auto dec_pos = std::find(number_buffer.begin(), number_buffer.end(), decimal_point);
+            if (dec_pos != number_buffer.end())
+            {
+                *dec_pos = '.';
+            }
+        }
+
+        o->write_characters(number_buffer.data(), static_cast<std::size_t>(len));
+
+        // determine if need to append ".0"
+        const bool value_is_int_like =
+            std::none_of(number_buffer.begin(), number_buffer.begin() + len + 1,
+                         [](char c)
+        {
+            return (c == '.' or c == 'e');
+        });
+
+        if (value_is_int_like)
+        {
+            o->write_characters(".0", 2);
+        }
+    }
+
+    /*!
+    @brief check whether a string is UTF-8 encoded
+
+    The function checks each byte of a string whether it is UTF-8 encoded. The
+    result of the check is stored in the @a state parameter. The function must
+    be called initially with state 0 (accept). State 1 means the string must
+    be rejected, because the current byte is not allowed. If the string is
+    completely processed, but the state is non-zero, the string ended
+    prematurely; that is, the last byte indicated more bytes should have
+    followed.
+
+    @param[in,out] state  the state of the decoding
+    @param[in,out] codep  codepoint (valid only if resulting state is UTF8_ACCEPT)
+    @param[in] byte       next byte to decode
+    @return               new state
+
+    @note The function has been edited: a std::array is used.
+
+    @copyright Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
+    @sa http://bjoern.hoehrmann.de/utf-8/decoder/dfa/
+    */
+    static uint8_t decode(uint8_t& state, uint32_t& codep, const uint8_t byte) noexcept
+    {
+        static const std::array<uint8_t, 400> utf8d =
+        {
+            {
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 00..1F
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20..3F
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 40..5F
+                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 60..7F
+                1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, // 80..9F
+                7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, // A0..BF
+                8, 8, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // C0..DF
+                0xA, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x4, 0x3, 0x3, // E0..EF
+                0xB, 0x6, 0x6, 0x6, 0x5, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, // F0..FF
+                0x0, 0x1, 0x2, 0x3, 0x5, 0x8, 0x7, 0x1, 0x1, 0x1, 0x4, 0x6, 0x1, 0x1, 0x1, 0x1, // s0..s0
+                1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, // s1..s2
+                1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, // s3..s4
+                1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, // s5..s6
+                1, 3, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 // s7..s8
+            }
+        };
+
+        const uint8_t type = utf8d[byte];
+
+        codep = (state != UTF8_ACCEPT)
+                ? (byte & 0x3fu) | (codep << 6)
+                : static_cast<uint32_t>(0xff >> type) & (byte);
+
+        state = utf8d[256u + state * 16u + type];
+        return state;
+    }
+
+  private:
+    /// the output of the serializer
+    output_adapter_t<char> o = nullptr;
+
+    /// a (hopefully) large enough character buffer
+    std::array<char, 64> number_buffer{{}};
+
+    /// the locale
+    const std::lconv* loc = nullptr;
+    /// the locale's thousand separator character
+    const char thousands_sep = '\0';
+    /// the locale's decimal point character
+    const char decimal_point = '\0';
+
+    /// string buffer
+    std::array<char, 512> string_buffer{{}};
+
+    /// the indentation character
+    const char indent_char;
+    /// the indentation string
+    string_t indent_string;
+
+    /// error_handler how to react on decoding errors
+    const error_handler_t error_handler;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/json_ref.hpp>
+
+
+#include <initializer_list>
+#include <utility>
+
+// #include <nlohmann/detail/meta/type_traits.hpp>
+
+
+namespace nlohmann
+{
+namespace detail
+{
+template<typename BasicJsonType>
+class json_ref
+{
+  public:
+    using value_type = BasicJsonType;
+
+    json_ref(value_type&& value)
+        : owned_value(std::move(value)), value_ref(&owned_value), is_rvalue(true)
+    {}
+
+    json_ref(const value_type& value)
+        : value_ref(const_cast<value_type*>(&value)), is_rvalue(false)
+    {}
+
+    json_ref(std::initializer_list<json_ref> init)
+        : owned_value(init), value_ref(&owned_value), is_rvalue(true)
+    {}
+
+    template <
+        class... Args,
+        enable_if_t<std::is_constructible<value_type, Args...>::value, int> = 0 >
+    json_ref(Args && ... args)
+        : owned_value(std::forward<Args>(args)...), value_ref(&owned_value),
+          is_rvalue(true) {}
+
+    // class should be movable only
+    json_ref(json_ref&&) = default;
+    json_ref(const json_ref&) = delete;
+    json_ref& operator=(const json_ref&) = delete;
+    json_ref& operator=(json_ref&&) = delete;
+    ~json_ref() = default;
+
+    value_type moved_or_copied() const
+    {
+        if (is_rvalue)
+        {
+            return std::move(*value_ref);
+        }
+        return *value_ref;
+    }
+
+    value_type const& operator*() const
+    {
+        return *static_cast<value_type const*>(value_ref);
+    }
+
+    value_type const* operator->() const
+    {
+        return static_cast<value_type const*>(value_ref);
+    }
+
+  private:
+    mutable value_type owned_value = nullptr;
+    value_type* value_ref = nullptr;
+    const bool is_rvalue;
+};
+}  // namespace detail
+}  // namespace nlohmann
+
+// #include <nlohmann/detail/json_pointer.hpp>
+
+
+#include <cassert> // assert
+#include <numeric> // accumulate
+#include <string> // string
+#include <vector> // vector
+
+// #include <nlohmann/detail/macro_scope.hpp>
+
+// #include <nlohmann/detail/exceptions.hpp>
+
+// #include <nlohmann/detail/value_t.hpp>
+
+
+namespace nlohmann
+{
+template<typename BasicJsonType>
+class json_pointer
+{
+    // allow basic_json to access private members
+    NLOHMANN_BASIC_JSON_TPL_DECLARATION
+    friend class basic_json;
+
+  public:
+    /*!
+    @brief create JSON pointer
+
+    Create a JSON pointer according to the syntax described in
+    [Section 3 of RFC6901](https://tools.ietf.org/html/rfc6901#section-3).
+
+    @param[in] s  string representing the JSON pointer; if omitted, the empty
+                  string is assumed which references the whole JSON value
+
+    @throw parse_error.107 if the given JSON pointer @a s is nonempty and does
+                           not begin with a slash (`/`); see example below
+
+    @throw parse_error.108 if a tilde (`~`) in the given JSON pointer @a s is
+    not followed by `0` (representing `~`) or `1` (representing `/`); see
+    example below
+
+    @liveexample{The example shows the construction several valid JSON pointers
+    as well as the exceptional behavior.,json_pointer}
+
+    @since version 2.0.0
+    */
+    explicit json_pointer(const std::string& s = "")
+        : reference_tokens(split(s))
+    {}
+
+    /*!
+    @brief return a string representation of the JSON pointer
+
+    @invariant For each JSON pointer `ptr`, it holds:
+    @code {.cpp}
+    ptr == json_pointer(ptr.to_string());
+    @endcode
+
+    @return a string representation of the JSON pointer
+
+    @liveexample{The example shows the result of `to_string`.,
+    json_pointer__to_string}
+
+    @since version 2.0.0
+    */
+    std::string to_string() const
+    {
+        return std::accumulate(reference_tokens.begin(), reference_tokens.end(),
+                               std::string{},
+                               [](const std::string & a, const std::string & b)
+        {
+            return a + "/" + escape(b);
+        });
+    }
+
+    /// @copydoc to_string()
+    operator std::string() const
+    {
+        return to_string();
+    }
+
+    /*!
+    @param[in] s  reference token to be converted into an array index
+
+    @return integer representation of @a s
+
+    @throw out_of_range.404 if string @a s could not be converted to an integer
+    */
+    static int array_index(const std::string& s)
+    {
+        std::size_t processed_chars = 0;
+        const int res = std::stoi(s, &processed_chars);
+
+        // check if the string was completely read
+        if (JSON_UNLIKELY(processed_chars != s.size()))
+        {
+            JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + s + "'"));
+        }
+
+        return res;
+    }
+
+  private:
+    /*!
+    @brief remove and return last reference pointer
+    @throw out_of_range.405 if JSON pointer has no parent
+    */
+    std::string pop_back()
+    {
+        if (JSON_UNLIKELY(is_root()))
+        {
+            JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent"));
+        }
+
+        auto last = reference_tokens.back();
+        reference_tokens.pop_back();
+        return last;
+    }
+
+    /// return whether pointer points to the root document
+    bool is_root() const noexcept
+    {
+        return reference_tokens.empty();
+    }
+
+    json_pointer top() const
+    {
+        if (JSON_UNLIKELY(is_root()))
+        {
+            JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent"));
+        }
+
+        json_pointer result = *this;
+        result.reference_tokens = {reference_tokens[0]};
+        return result;
+    }
+
+    /*!
+    @brief create and return a reference to the pointed to value
+
+    @complexity Linear in the number of reference tokens.
+
+    @throw parse_error.109 if array index is not a number
+    @throw type_error.313 if value cannot be unflattened
+    */
+    BasicJsonType& get_and_create(BasicJsonType& j) const
+    {
+        using size_type = typename BasicJsonType::size_type;
+        auto result = &j;
+
+        // in case no reference tokens exist, return a reference to the JSON value
+        // j which will be overwritten by a primitive value
+        for (const auto& reference_token : reference_tokens)
+        {
+            switch (result->m_type)
+            {
+                case detail::value_t::null:
+                {
+                    if (reference_token == "0")
+                    {
+                        // start a new array if reference token is 0
+                        result = &result->operator[](0);
+                    }
+                    else
+                    {
+                        // start a new object otherwise
+                        result = &result->operator[](reference_token);
+                    }
+                    break;
+                }
+
+                case detail::value_t::object:
+                {
+                    // create an entry in the object
+                    result = &result->operator[](reference_token);
+                    break;
+                }
+
+                case detail::value_t::array:
+                {
+                    // create an entry in the array
+                    JSON_TRY
+                    {
+                        result = &result->operator[](static_cast<size_type>(array_index(reference_token)));
+                    }
+                    JSON_CATCH(std::invalid_argument&)
+                    {
+                        JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number"));
+                    }
+                    break;
+                }
+
+                /*
+                The following code is only reached if there exists a reference
+                token _and_ the current value is primitive. In this case, we have
+                an error situation, because primitive values may only occur as
+                single value; that is, with an empty list of reference tokens.
+                */
+                default:
+                    JSON_THROW(detail::type_error::create(313, "invalid value to unflatten"));
+            }
+        }
+
+        return *result;
+    }
+
+    /*!
+    @brief return a reference to the pointed to value
+
+    @note This version does not throw if a value is not present, but tries to
+          create nested values instead. For instance, calling this function
+          with pointer `"/this/that"` on a null value is equivalent to calling
+          `operator[]("this").operator[]("that")` on that value, effectively
+          changing the null value to an object.
+
+    @param[in] ptr  a JSON value
+
+    @return reference to the JSON value pointed to by the JSON pointer
+
+    @complexity Linear in the length of the JSON pointer.
+
+    @throw parse_error.106   if an array index begins with '0'
+    @throw parse_error.109   if an array index was not a number
+    @throw out_of_range.404  if the JSON pointer can not be resolved
+    */
+    BasicJsonType& get_unchecked(BasicJsonType* ptr) const
+    {
+        using size_type = typename BasicJsonType::size_type;
+        for (const auto& reference_token : reference_tokens)
+        {
+            // convert null values to arrays or objects before continuing
+            if (ptr->m_type == detail::value_t::null)
+            {
+                // check if reference token is a number
+                const bool nums =
+                    std::all_of(reference_token.begin(), reference_token.end(),
+                                [](const char x)
+                {
+                    return (x >= '0' and x <= '9');
+                });
+
+                // change value to array for numbers or "-" or to object otherwise
+                *ptr = (nums or reference_token == "-")
+                       ? detail::value_t::array
+                       : detail::value_t::object;
+            }
+
+            switch (ptr->m_type)
+            {
+                case detail::value_t::object:
+                {
+                    // use unchecked object access
+                    ptr = &ptr->operator[](reference_token);
+                    break;
+                }
+
+                case detail::value_t::array:
+                {
+                    // error condition (cf. RFC 6901, Sect. 4)
+                    if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0'))
+                    {
+                        JSON_THROW(detail::parse_error::create(106, 0,
+                                                               "array index '" + reference_token +
+                                                               "' must not begin with '0'"));
+                    }
+
+                    if (reference_token == "-")
+                    {
+                        // explicitly treat "-" as index beyond the end
+                        ptr = &ptr->operator[](ptr->m_value.array->size());
+                    }
+                    else
+                    {
+                        // convert array index to number; unchecked access
+                        JSON_TRY
+                        {
+                            ptr = &ptr->operator[](
+                                static_cast<size_type>(array_index(reference_token)));
+                        }
+                        JSON_CATCH(std::invalid_argument&)
+                        {
+                            JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number"));
+                        }
+                    }
+                    break;
+                }
+
+                default:
+                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'"));
+            }
+        }
+
+        return *ptr;
+    }
+
+    /*!
+    @throw parse_error.106   if an array index begins with '0'
+    @throw parse_error.109   if an array index was not a number
+    @throw out_of_range.402  if the array index '-' is used
+    @throw out_of_range.404  if the JSON pointer can not be resolved
+    */
+    BasicJsonType& get_checked(BasicJsonType* ptr) const
+    {
+        using size_type = typename BasicJsonType::size_type;
+        for (const auto& reference_token : reference_tokens)
+        {
+            switch (ptr->m_type)
+            {
+                case detail::value_t::object:
+                {
+                    // note: at performs range check
+                    ptr = &ptr->at(reference_token);
+                    break;
+                }
+
+                case detail::value_t::array:
+                {
+                    if (JSON_UNLIKELY(reference_token == "-"))
+                    {
+                        // "-" always fails the range check
+                        JSON_THROW(detail::out_of_range::create(402,
+                                                                "array index '-' (" + std::to_string(ptr->m_value.array->size()) +
+                                                                ") is out of range"));
+                    }
+
+                    // error condition (cf. RFC 6901, Sect. 4)
+                    if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0'))
+                    {
+                        JSON_THROW(detail::parse_error::create(106, 0,
+                                                               "array index '" + reference_token +
+                                                               "' must not begin with '0'"));
+                    }
+
+                    // note: at performs range check
+                    JSON_TRY
+                    {
+                        ptr = &ptr->at(static_cast<size_type>(array_index(reference_token)));
+                    }
+                    JSON_CATCH(std::invalid_argument&)
+                    {
+                        JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number"));
+                    }
+                    break;
+                }
+
+                default:
+                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'"));
+            }
+        }
+
+        return *ptr;
+    }
+
+    /*!
+    @brief return a const reference to the pointed to value
+
+    @param[in] ptr  a JSON value
+
+    @return const reference to the JSON value pointed to by the JSON
+    pointer
+
+    @throw parse_error.106   if an array index begins with '0'
+    @throw parse_error.109   if an array index was not a number
+    @throw out_of_range.402  if the array index '-' is used
+    @throw out_of_range.404  if the JSON pointer can not be resolved
+    */
+    const BasicJsonType& get_unchecked(const BasicJsonType* ptr) const
+    {
+        using size_type = typename BasicJsonType::size_type;
+        for (const auto& reference_token : reference_tokens)
+        {
+            switch (ptr->m_type)
+            {
+                case detail::value_t::object:
+                {
+                    // use unchecked object access
+                    ptr = &ptr->operator[](reference_token);
+                    break;
+                }
+
+                case detail::value_t::array:
+                {
+                    if (JSON_UNLIKELY(reference_token == "-"))
+                    {
+                        // "-" cannot be used for const access
+                        JSON_THROW(detail::out_of_range::create(402,
+                                                                "array index '-' (" + std::to_string(ptr->m_value.array->size()) +
+                                                                ") is out of range"));
+                    }
+
+                    // error condition (cf. RFC 6901, Sect. 4)
+                    if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0'))
+                    {
+                        JSON_THROW(detail::parse_error::create(106, 0,
+                                                               "array index '" + reference_token +
+                                                               "' must not begin with '0'"));
+                    }
+
+                    // use unchecked array access
+                    JSON_TRY
+                    {
+                        ptr = &ptr->operator[](
+                            static_cast<size_type>(array_index(reference_token)));
+                    }
+                    JSON_CATCH(std::invalid_argument&)
+                    {
+                        JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number"));
+                    }
+                    break;
+                }
+
+                default:
+                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'"));
+            }
+        }
+
+        return *ptr;
+    }
+
+    /*!
+    @throw parse_error.106   if an array index begins with '0'
+    @throw parse_error.109   if an array index was not a number
+    @throw out_of_range.402  if the array index '-' is used
+    @throw out_of_range.404  if the JSON pointer can not be resolved
+    */
+    const BasicJsonType& get_checked(const BasicJsonType* ptr) const
+    {
+        using size_type = typename BasicJsonType::size_type;
+        for (const auto& reference_token : reference_tokens)
+        {
+            switch (ptr->m_type)
+            {
+                case detail::value_t::object:
+                {
+                    // note: at performs range check
+                    ptr = &ptr->at(reference_token);
+                    break;
+                }
+
+                case detail::value_t::array:
+                {
+                    if (JSON_UNLIKELY(reference_token == "-"))
+                    {
+                        // "-" always fails the range check
+                        JSON_THROW(detail::out_of_range::create(402,
+                                                                "array index '-' (" + std::to_string(ptr->m_value.array->size()) +
+                                                                ") is out of range"));
+                    }
+
+                    // error condition (cf. RFC 6901, Sect. 4)
+                    if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0'))
+                    {
+                        JSON_THROW(detail::parse_error::create(106, 0,
+                                                               "array index '" + reference_token +
+                                                               "' must not begin with '0'"));
+                    }
+
+                    // note: at performs range check
+                    JSON_TRY
+                    {
+                        ptr = &ptr->at(static_cast<size_type>(array_index(reference_token)));
+                    }
+                    JSON_CATCH(std::invalid_argument&)
+                    {
+                        JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number"));
+                    }
+                    break;
+                }
+
+                default:
+                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'"));
+            }
+        }
+
+        return *ptr;
+    }
+
+    /*!
+    @brief split the string input to reference tokens
+
+    @note This function is only called by the json_pointer constructor.
+          All exceptions below are documented there.
+
+    @throw parse_error.107  if the pointer is not empty or begins with '/'
+    @throw parse_error.108  if character '~' is not followed by '0' or '1'
+    */
+    static std::vector<std::string> split(const std::string& reference_string)
+    {
+        std::vector<std::string> result;
+
+        // special case: empty reference string -> no reference tokens
+        if (reference_string.empty())
+        {
+            return result;
+        }
+
+        // check if nonempty reference string begins with slash
+        if (JSON_UNLIKELY(reference_string[0] != '/'))
+        {
+            JSON_THROW(detail::parse_error::create(107, 1,
+                                                   "JSON pointer must be empty or begin with '/' - was: '" +
+                                                   reference_string + "'"));
+        }
+
+        // extract the reference tokens:
+        // - slash: position of the last read slash (or end of string)
+        // - start: position after the previous slash
+        for (
+            // search for the first slash after the first character
+            std::size_t slash = reference_string.find_first_of('/', 1),
+            // set the beginning of the first reference token
+            start = 1;
+            // we can stop if start == 0 (if slash == std::string::npos)
+            start != 0;
+            // set the beginning of the next reference token
+            // (will eventually be 0 if slash == std::string::npos)
+            start = (slash == std::string::npos) ? 0 : slash + 1,
+            // find next slash
+            slash = reference_string.find_first_of('/', start))
+        {
+            // use the text between the beginning of the reference token
+            // (start) and the last slash (slash).
+            auto reference_token = reference_string.substr(start, slash - start);
+
+            // check reference tokens are properly escaped
+            for (std::size_t pos = reference_token.find_first_of('~');
+                    pos != std::string::npos;
+                    pos = reference_token.find_first_of('~', pos + 1))
+            {
+                assert(reference_token[pos] == '~');
+
+                // ~ must be followed by 0 or 1
+                if (JSON_UNLIKELY(pos == reference_token.size() - 1 or
+                                  (reference_token[pos + 1] != '0' and
+                                   reference_token[pos + 1] != '1')))
+                {
+                    JSON_THROW(detail::parse_error::create(108, 0, "escape character '~' must be followed with '0' or '1'"));
+                }
+            }
+
+            // finally, store the reference token
+            unescape(reference_token);
+            result.push_back(reference_token);
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief replace all occurrences of a substring by another string
+
+    @param[in,out] s  the string to manipulate; changed so that all
+                   occurrences of @a f are replaced with @a t
+    @param[in]     f  the substring to replace with @a t
+    @param[in]     t  the string to replace @a f
+
+    @pre The search string @a f must not be empty. **This precondition is
+    enforced with an assertion.**
+
+    @since version 2.0.0
+    */
+    static void replace_substring(std::string& s, const std::string& f,
+                                  const std::string& t)
+    {
+        assert(not f.empty());
+        for (auto pos = s.find(f);                // find first occurrence of f
+                pos != std::string::npos;         // make sure f was found
+                s.replace(pos, f.size(), t),      // replace with t, and
+                pos = s.find(f, pos + t.size()))  // find next occurrence of f
+        {}
+    }
+
+    /// escape "~" to "~0" and "/" to "~1"
+    static std::string escape(std::string s)
+    {
+        replace_substring(s, "~", "~0");
+        replace_substring(s, "/", "~1");
+        return s;
+    }
+
+    /// unescape "~1" to tilde and "~0" to slash (order is important!)
+    static void unescape(std::string& s)
+    {
+        replace_substring(s, "~1", "/");
+        replace_substring(s, "~0", "~");
+    }
+
+    /*!
+    @param[in] reference_string  the reference string to the current value
+    @param[in] value             the value to consider
+    @param[in,out] result        the result object to insert values to
+
+    @note Empty objects or arrays are flattened to `null`.
+    */
+    static void flatten(const std::string& reference_string,
+                        const BasicJsonType& value,
+                        BasicJsonType& result)
+    {
+        switch (value.m_type)
+        {
+            case detail::value_t::array:
+            {
+                if (value.m_value.array->empty())
+                {
+                    // flatten empty array as null
+                    result[reference_string] = nullptr;
+                }
+                else
+                {
+                    // iterate array and use index as reference string
+                    for (std::size_t i = 0; i < value.m_value.array->size(); ++i)
+                    {
+                        flatten(reference_string + "/" + std::to_string(i),
+                                value.m_value.array->operator[](i), result);
+                    }
+                }
+                break;
+            }
+
+            case detail::value_t::object:
+            {
+                if (value.m_value.object->empty())
+                {
+                    // flatten empty object as null
+                    result[reference_string] = nullptr;
+                }
+                else
+                {
+                    // iterate object and use keys as reference string
+                    for (const auto& element : *value.m_value.object)
+                    {
+                        flatten(reference_string + "/" + escape(element.first), element.second, result);
+                    }
+                }
+                break;
+            }
+
+            default:
+            {
+                // add primitive value with its reference string
+                result[reference_string] = value;
+                break;
+            }
+        }
+    }
+
+    /*!
+    @param[in] value  flattened JSON
+
+    @return unflattened JSON
+
+    @throw parse_error.109 if array index is not a number
+    @throw type_error.314  if value is not an object
+    @throw type_error.315  if object values are not primitive
+    @throw type_error.313  if value cannot be unflattened
+    */
+    static BasicJsonType
+    unflatten(const BasicJsonType& value)
+    {
+        if (JSON_UNLIKELY(not value.is_object()))
+        {
+            JSON_THROW(detail::type_error::create(314, "only objects can be unflattened"));
+        }
+
+        BasicJsonType result;
+
+        // iterate the JSON object values
+        for (const auto& element : *value.m_value.object)
+        {
+            if (JSON_UNLIKELY(not element.second.is_primitive()))
+            {
+                JSON_THROW(detail::type_error::create(315, "values in object must be primitive"));
+            }
+
+            // assign value to reference pointed to by JSON pointer; Note that if
+            // the JSON pointer is "" (i.e., points to the whole value), function
+            // get_and_create returns a reference to result itself. An assignment
+            // will then create a primitive value.
+            json_pointer(element.first).get_and_create(result) = element.second;
+        }
+
+        return result;
+    }
+
+    friend bool operator==(json_pointer const& lhs,
+                           json_pointer const& rhs) noexcept
+    {
+        return (lhs.reference_tokens == rhs.reference_tokens);
+    }
+
+    friend bool operator!=(json_pointer const& lhs,
+                           json_pointer const& rhs) noexcept
+    {
+        return not (lhs == rhs);
+    }
+
+    /// the reference tokens
+    std::vector<std::string> reference_tokens;
+};
+}  // namespace nlohmann
+
+// #include <nlohmann/adl_serializer.hpp>
+
+
+#include <utility>
+
+// #include <nlohmann/detail/conversions/from_json.hpp>
+
+// #include <nlohmann/detail/conversions/to_json.hpp>
+
+
+namespace nlohmann
+{
+
+template<typename, typename>
+struct adl_serializer
+{
+    /*!
+    @brief convert a JSON value to any value type
+
+    This function is usually called by the `get()` function of the
+    @ref basic_json class (either explicit or via conversion operators).
+
+    @param[in] j        JSON value to read from
+    @param[in,out] val  value to write to
+    */
+    template<typename BasicJsonType, typename ValueType>
+    static auto from_json(BasicJsonType&& j, ValueType& val) noexcept(
+        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val)))
+    -> decltype(::nlohmann::from_json(std::forward<BasicJsonType>(j), val), void())
+    {
+        ::nlohmann::from_json(std::forward<BasicJsonType>(j), val);
+    }
+
+    /*!
+    @brief convert any value type to a JSON value
+
+    This function is usually called by the constructors of the @ref basic_json
+    class.
+
+    @param[in,out] j  JSON value to write to
+    @param[in] val    value to read from
+    */
+    template <typename BasicJsonType, typename ValueType>
+    static auto to_json(BasicJsonType& j, ValueType&& val) noexcept(
+        noexcept(::nlohmann::to_json(j, std::forward<ValueType>(val))))
+    -> decltype(::nlohmann::to_json(j, std::forward<ValueType>(val)), void())
+    {
+        ::nlohmann::to_json(j, std::forward<ValueType>(val));
+    }
+};
+
+}  // namespace nlohmann
+
+
+/*!
+@brief namespace for Niels Lohmann
+@see https://github.com/nlohmann
+@since version 1.0.0
+*/
+namespace nlohmann
+{
+
+/*!
+@brief a class to store JSON values
+
+@tparam ObjectType type for JSON objects (`std::map` by default; will be used
+in @ref object_t)
+@tparam ArrayType type for JSON arrays (`std::vector` by default; will be used
+in @ref array_t)
+@tparam StringType type for JSON strings and object keys (`std::string` by
+default; will be used in @ref string_t)
+@tparam BooleanType type for JSON booleans (`bool` by default; will be used
+in @ref boolean_t)
+@tparam NumberIntegerType type for JSON integer numbers (`int64_t` by
+default; will be used in @ref number_integer_t)
+@tparam NumberUnsignedType type for JSON unsigned integer numbers (@c
+`uint64_t` by default; will be used in @ref number_unsigned_t)
+@tparam NumberFloatType type for JSON floating-point numbers (`double` by
+default; will be used in @ref number_float_t)
+@tparam AllocatorType type of the allocator to use (`std::allocator` by
+default)
+@tparam JSONSerializer the serializer to resolve internal calls to `to_json()`
+and `from_json()` (@ref adl_serializer by default)
+
+@requirement The class satisfies the following concept requirements:
+- Basic
+ - [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible):
+   JSON values can be default constructed. The result will be a JSON null
+   value.
+ - [MoveConstructible](https://en.cppreference.com/w/cpp/named_req/MoveConstructible):
+   A JSON value can be constructed from an rvalue argument.
+ - [CopyConstructible](https://en.cppreference.com/w/cpp/named_req/CopyConstructible):
+   A JSON value can be copy-constructed from an lvalue expression.
+ - [MoveAssignable](https://en.cppreference.com/w/cpp/named_req/MoveAssignable):
+   A JSON value van be assigned from an rvalue argument.
+ - [CopyAssignable](https://en.cppreference.com/w/cpp/named_req/CopyAssignable):
+   A JSON value can be copy-assigned from an lvalue expression.
+ - [Destructible](https://en.cppreference.com/w/cpp/named_req/Destructible):
+   JSON values can be destructed.
+- Layout
+ - [StandardLayoutType](https://en.cppreference.com/w/cpp/named_req/StandardLayoutType):
+   JSON values have
+   [standard layout](https://en.cppreference.com/w/cpp/language/data_members#Standard_layout):
+   All non-static data members are private and standard layout types, the
+   class has no virtual functions or (virtual) base classes.
+- Library-wide
+ - [EqualityComparable](https://en.cppreference.com/w/cpp/named_req/EqualityComparable):
+   JSON values can be compared with `==`, see @ref
+   operator==(const_reference,const_reference).
+ - [LessThanComparable](https://en.cppreference.com/w/cpp/named_req/LessThanComparable):
+   JSON values can be compared with `<`, see @ref
+   operator<(const_reference,const_reference).
+ - [Swappable](https://en.cppreference.com/w/cpp/named_req/Swappable):
+   Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of
+   other compatible types, using unqualified function call @ref swap().
+ - [NullablePointer](https://en.cppreference.com/w/cpp/named_req/NullablePointer):
+   JSON values can be compared against `std::nullptr_t` objects which are used
+   to model the `null` value.
+- Container
+ - [Container](https://en.cppreference.com/w/cpp/named_req/Container):
+   JSON values can be used like STL containers and provide iterator access.
+ - [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer);
+   JSON values can be used like STL containers and provide reverse iterator
+   access.
+
+@invariant The member variables @a m_value and @a m_type have the following
+relationship:
+- If `m_type == value_t::object`, then `m_value.object != nullptr`.
+- If `m_type == value_t::array`, then `m_value.array != nullptr`.
+- If `m_type == value_t::string`, then `m_value.string != nullptr`.
+The invariants are checked by member function assert_invariant().
+
+@internal
+@note ObjectType trick from http://stackoverflow.com/a/9860911
+@endinternal
+
+@see [RFC 7159: The JavaScript Object Notation (JSON) Data Interchange
+Format](http://rfc7159.net/rfc7159)
+
+@since version 1.0.0
+
+@nosubgrouping
+*/
+NLOHMANN_BASIC_JSON_TPL_DECLARATION
+class basic_json
+{
+  private:
+    template<detail::value_t> friend struct detail::external_constructor;
+    friend ::nlohmann::json_pointer<basic_json>;
+    friend ::nlohmann::detail::parser<basic_json>;
+    friend ::nlohmann::detail::serializer<basic_json>;
+    template<typename BasicJsonType>
+    friend class ::nlohmann::detail::iter_impl;
+    template<typename BasicJsonType, typename CharType>
+    friend class ::nlohmann::detail::binary_writer;
+    template<typename BasicJsonType, typename SAX>
+    friend class ::nlohmann::detail::binary_reader;
+    template<typename BasicJsonType>
+    friend class ::nlohmann::detail::json_sax_dom_parser;
+    template<typename BasicJsonType>
+    friend class ::nlohmann::detail::json_sax_dom_callback_parser;
+
+    /// workaround type for MSVC
+    using basic_json_t = NLOHMANN_BASIC_JSON_TPL;
+
+    // convenience aliases for types residing in namespace detail;
+    using lexer = ::nlohmann::detail::lexer<basic_json>;
+    using parser = ::nlohmann::detail::parser<basic_json>;
+
+    using primitive_iterator_t = ::nlohmann::detail::primitive_iterator_t;
+    template<typename BasicJsonType>
+    using internal_iterator = ::nlohmann::detail::internal_iterator<BasicJsonType>;
+    template<typename BasicJsonType>
+    using iter_impl = ::nlohmann::detail::iter_impl<BasicJsonType>;
+    template<typename Iterator>
+    using iteration_proxy = ::nlohmann::detail::iteration_proxy<Iterator>;
+    template<typename Base> using json_reverse_iterator = ::nlohmann::detail::json_reverse_iterator<Base>;
+
+    template<typename CharType>
+    using output_adapter_t = ::nlohmann::detail::output_adapter_t<CharType>;
+
+    using binary_reader = ::nlohmann::detail::binary_reader<basic_json>;
+    template<typename CharType> using binary_writer = ::nlohmann::detail::binary_writer<basic_json, CharType>;
+
+    using serializer = ::nlohmann::detail::serializer<basic_json>;
+
+  public:
+    using value_t = detail::value_t;
+    /// JSON Pointer, see @ref nlohmann::json_pointer
+    using json_pointer = ::nlohmann::json_pointer<basic_json>;
+    template<typename T, typename SFINAE>
+    using json_serializer = JSONSerializer<T, SFINAE>;
+    /// how to treat decoding errors
+    using error_handler_t = detail::error_handler_t;
+    /// helper type for initializer lists of basic_json values
+    using initializer_list_t = std::initializer_list<detail::json_ref<basic_json>>;
+
+    using input_format_t = detail::input_format_t;
+    /// SAX interface type, see @ref nlohmann::json_sax
+    using json_sax_t = json_sax<basic_json>;
+
+    ////////////////
+    // exceptions //
+    ////////////////
+
+    /// @name exceptions
+    /// Classes to implement user-defined exceptions.
+    /// @{
+
+    /// @copydoc detail::exception
+    using exception = detail::exception;
+    /// @copydoc detail::parse_error
+    using parse_error = detail::parse_error;
+    /// @copydoc detail::invalid_iterator
+    using invalid_iterator = detail::invalid_iterator;
+    /// @copydoc detail::type_error
+    using type_error = detail::type_error;
+    /// @copydoc detail::out_of_range
+    using out_of_range = detail::out_of_range;
+    /// @copydoc detail::other_error
+    using other_error = detail::other_error;
+
+    /// @}
+
+
+    /////////////////////
+    // container types //
+    /////////////////////
+
+    /// @name container types
+    /// The canonic container types to use @ref basic_json like any other STL
+    /// container.
+    /// @{
+
+    /// the type of elements in a basic_json container
+    using value_type = basic_json;
+
+    /// the type of an element reference
+    using reference = value_type&;
+    /// the type of an element const reference
+    using const_reference = const value_type&;
+
+    /// a type to represent differences between iterators
+    using difference_type = std::ptrdiff_t;
+    /// a type to represent container sizes
+    using size_type = std::size_t;
+
+    /// the allocator type
+    using allocator_type = AllocatorType<basic_json>;
+
+    /// the type of an element pointer
+    using pointer = typename std::allocator_traits<allocator_type>::pointer;
+    /// the type of an element const pointer
+    using const_pointer = typename std::allocator_traits<allocator_type>::const_pointer;
+
+    /// an iterator for a basic_json container
+    using iterator = iter_impl<basic_json>;
+    /// a const iterator for a basic_json container
+    using const_iterator = iter_impl<const basic_json>;
+    /// a reverse iterator for a basic_json container
+    using reverse_iterator = json_reverse_iterator<typename basic_json::iterator>;
+    /// a const reverse iterator for a basic_json container
+    using const_reverse_iterator = json_reverse_iterator<typename basic_json::const_iterator>;
+
+    /// @}
+
+
+    /*!
+    @brief returns the allocator associated with the container
+    */
+    static allocator_type get_allocator()
+    {
+        return allocator_type();
+    }
+
+    /*!
+    @brief returns version information on the library
+
+    This function returns a JSON object with information about the library,
+    including the version number and information on the platform and compiler.
+
+    @return JSON object holding version information
+    key         | description
+    ----------- | ---------------
+    `compiler`  | Information on the used compiler. It is an object with the following keys: `c++` (the used C++ standard), `family` (the compiler family; possible values are `clang`, `icc`, `gcc`, `ilecpp`, `msvc`, `pgcpp`, `sunpro`, and `unknown`), and `version` (the compiler version).
+    `copyright` | The copyright line for the library as string.
+    `name`      | The name of the library as string.
+    `platform`  | The used platform as string. Possible values are `win32`, `linux`, `apple`, `unix`, and `unknown`.
+    `url`       | The URL of the project as string.
+    `version`   | The version of the library. It is an object with the following keys: `major`, `minor`, and `patch` as defined by [Semantic Versioning](http://semver.org), and `string` (the version string).
+
+    @liveexample{The following code shows an example output of the `meta()`
+    function.,meta}
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @complexity Constant.
+
+    @since 2.1.0
+    */
+    static basic_json meta()
+    {
+        basic_json result;
+
+        result["copyright"] = "(C) 2013-2017 Niels Lohmann";
+        result["name"] = "JSON for Modern C++";
+        result["url"] = "https://github.com/nlohmann/json";
+        result["version"]["string"] =
+            std::to_string(NLOHMANN_JSON_VERSION_MAJOR) + "." +
+            std::to_string(NLOHMANN_JSON_VERSION_MINOR) + "." +
+            std::to_string(NLOHMANN_JSON_VERSION_PATCH);
+        result["version"]["major"] = NLOHMANN_JSON_VERSION_MAJOR;
+        result["version"]["minor"] = NLOHMANN_JSON_VERSION_MINOR;
+        result["version"]["patch"] = NLOHMANN_JSON_VERSION_PATCH;
+
+#ifdef _WIN32
+        result["platform"] = "win32";
+#elif defined __linux__
+        result["platform"] = "linux";
+#elif defined __APPLE__
+        result["platform"] = "apple";
+#elif defined __unix__
+        result["platform"] = "unix";
+#else
+        result["platform"] = "unknown";
+#endif
+
+#if defined(__ICC) || defined(__INTEL_COMPILER)
+        result["compiler"] = {{"family", "icc"}, {"version", __INTEL_COMPILER}};
+#elif defined(__clang__)
+        result["compiler"] = {{"family", "clang"}, {"version", __clang_version__}};
+#elif defined(__GNUC__) || defined(__GNUG__)
+        result["compiler"] = {{"family", "gcc"}, {"version", std::to_string(__GNUC__) + "." + std::to_string(__GNUC_MINOR__) + "." + std::to_string(__GNUC_PATCHLEVEL__)}};
+#elif defined(__HP_cc) || defined(__HP_aCC)
+        result["compiler"] = "hp"
+#elif defined(__IBMCPP__)
+        result["compiler"] = {{"family", "ilecpp"}, {"version", __IBMCPP__}};
+#elif defined(_MSC_VER)
+        result["compiler"] = {{"family", "msvc"}, {"version", _MSC_VER}};
+#elif defined(__PGI)
+        result["compiler"] = {{"family", "pgcpp"}, {"version", __PGI}};
+#elif defined(__SUNPRO_CC)
+        result["compiler"] = {{"family", "sunpro"}, {"version", __SUNPRO_CC}};
+#else
+        result["compiler"] = {{"family", "unknown"}, {"version", "unknown"}};
+#endif
+
+#ifdef __cplusplus
+        result["compiler"]["c++"] = std::to_string(__cplusplus);
+#else
+        result["compiler"]["c++"] = "unknown";
+#endif
+        return result;
+    }
+
+
+    ///////////////////////////
+    // JSON value data types //
+    ///////////////////////////
+
+    /// @name JSON value data types
+    /// The data types to store a JSON value. These types are derived from
+    /// the template arguments passed to class @ref basic_json.
+    /// @{
+
+#if defined(JSON_HAS_CPP_14)
+    // Use transparent comparator if possible, combined with perfect forwarding
+    // on find() and count() calls prevents unnecessary string construction.
+    using object_comparator_t = std::less<>;
+#else
+    using object_comparator_t = std::less<StringType>;
+#endif
+
+    /*!
+    @brief a type for an object
+
+    [RFC 7159](http://rfc7159.net/rfc7159) describes JSON objects as follows:
+    > An object is an unordered collection of zero or more name/value pairs,
+    > where a name is a string and a value is a string, number, boolean, null,
+    > object, or array.
+
+    To store objects in C++, a type is defined by the template parameters
+    described below.
+
+    @tparam ObjectType  the container to store objects (e.g., `std::map` or
+    `std::unordered_map`)
+    @tparam StringType the type of the keys or names (e.g., `std::string`).
+    The comparison function `std::less<StringType>` is used to order elements
+    inside the container.
+    @tparam AllocatorType the allocator to use for objects (e.g.,
+    `std::allocator`)
+
+    #### Default type
+
+    With the default values for @a ObjectType (`std::map`), @a StringType
+    (`std::string`), and @a AllocatorType (`std::allocator`), the default
+    value for @a object_t is:
+
+    @code {.cpp}
+    std::map<
+      std::string, // key_type
+      basic_json, // value_type
+      std::less<std::string>, // key_compare
+      std::allocator<std::pair<const std::string, basic_json>> // allocator_type
+    >
+    @endcode
+
+    #### Behavior
+
+    The choice of @a object_t influences the behavior of the JSON class. With
+    the default type, objects have the following behavior:
+
+    - When all names are unique, objects will be interoperable in the sense
+      that all software implementations receiving that object will agree on
+      the name-value mappings.
+    - When the names within an object are not unique, it is unspecified which
+      one of the values for a given key will be chosen. For instance,
+      `{"key": 2, "key": 1}` could be equal to either `{"key": 1}` or
+      `{"key": 2}`.
+    - Internally, name/value pairs are stored in lexicographical order of the
+      names. Objects will also be serialized (see @ref dump) in this order.
+      For instance, `{"b": 1, "a": 2}` and `{"a": 2, "b": 1}` will be stored
+      and serialized as `{"a": 2, "b": 1}`.
+    - When comparing objects, the order of the name/value pairs is irrelevant.
+      This makes objects interoperable in the sense that they will not be
+      affected by these differences. For instance, `{"b": 1, "a": 2}` and
+      `{"a": 2, "b": 1}` will be treated as equal.
+
+    #### Limits
+
+    [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+    > An implementation may set limits on the maximum depth of nesting.
+
+    In this class, the object's limit of nesting is not explicitly constrained.
+    However, a maximum depth of nesting may be introduced by the compiler or
+    runtime environment. A theoretical limit can be queried by calling the
+    @ref max_size function of a JSON object.
+
+    #### Storage
+
+    Objects are stored as pointers in a @ref basic_json type. That is, for any
+    access to object values, a pointer of type `object_t*` must be
+    dereferenced.
+
+    @sa @ref array_t -- type for an array value
+
+    @since version 1.0.0
+
+    @note The order name/value pairs are added to the object is *not*
+    preserved by the library. Therefore, iterating an object may return
+    name/value pairs in a different order than they were originally stored. In
+    fact, keys will be traversed in alphabetical order as `std::map` with
+    `std::less` is used by default. Please note this behavior conforms to [RFC
+    7159](http://rfc7159.net/rfc7159), because any order implements the
+    specified "unordered" nature of JSON objects.
+    */
+    using object_t = ObjectType<StringType,
+          basic_json,
+          object_comparator_t,
+          AllocatorType<std::pair<const StringType,
+          basic_json>>>;
+
+    /*!
+    @brief a type for an array
+
+    [RFC 7159](http://rfc7159.net/rfc7159) describes JSON arrays as follows:
+    > An array is an ordered sequence of zero or more values.
+
+    To store objects in C++, a type is defined by the template parameters
+    explained below.
+
+    @tparam ArrayType  container type to store arrays (e.g., `std::vector` or
+    `std::list`)
+    @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`)
+
+    #### Default type
+
+    With the default values for @a ArrayType (`std::vector`) and @a
+    AllocatorType (`std::allocator`), the default value for @a array_t is:
+
+    @code {.cpp}
+    std::vector<
+      basic_json, // value_type
+      std::allocator<basic_json> // allocator_type
+    >
+    @endcode
+
+    #### Limits
+
+    [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+    > An implementation may set limits on the maximum depth of nesting.
+
+    In this class, the array's limit of nesting is not explicitly constrained.
+    However, a maximum depth of nesting may be introduced by the compiler or
+    runtime environment. A theoretical limit can be queried by calling the
+    @ref max_size function of a JSON array.
+
+    #### Storage
+
+    Arrays are stored as pointers in a @ref basic_json type. That is, for any
+    access to array values, a pointer of type `array_t*` must be dereferenced.
+
+    @sa @ref object_t -- type for an object value
+
+    @since version 1.0.0
+    */
+    using array_t = ArrayType<basic_json, AllocatorType<basic_json>>;
+
+    /*!
+    @brief a type for a string
+
+    [RFC 7159](http://rfc7159.net/rfc7159) describes JSON strings as follows:
+    > A string is a sequence of zero or more Unicode characters.
+
+    To store objects in C++, a type is defined by the template parameter
+    described below. Unicode values are split by the JSON class into
+    byte-sized characters during deserialization.
+
+    @tparam StringType  the container to store strings (e.g., `std::string`).
+    Note this container is used for keys/names in objects, see @ref object_t.
+
+    #### Default type
+
+    With the default values for @a StringType (`std::string`), the default
+    value for @a string_t is:
+
+    @code {.cpp}
+    std::string
+    @endcode
+
+    #### Encoding
+
+    Strings are stored in UTF-8 encoding. Therefore, functions like
+    `std::string::size()` or `std::string::length()` return the number of
+    bytes in the string rather than the number of characters or glyphs.
+
+    #### String comparison
+
+    [RFC 7159](http://rfc7159.net/rfc7159) states:
+    > Software implementations are typically required to test names of object
+    > members for equality. Implementations that transform the textual
+    > representation into sequences of Unicode code units and then perform the
+    > comparison numerically, code unit by code unit, are interoperable in the
+    > sense that implementations will agree in all cases on equality or
+    > inequality of two strings. For example, implementations that compare
+    > strings with escaped characters unconverted may incorrectly find that
+    > `"a\\b"` and `"a\u005Cb"` are not equal.
+
+    This implementation is interoperable as it does compare strings code unit
+    by code unit.
+
+    #### Storage
+
+    String values are stored as pointers in a @ref basic_json type. That is,
+    for any access to string values, a pointer of type `string_t*` must be
+    dereferenced.
+
+    @since version 1.0.0
+    */
+    using string_t = StringType;
+
+    /*!
+    @brief a type for a boolean
+
+    [RFC 7159](http://rfc7159.net/rfc7159) implicitly describes a boolean as a
+    type which differentiates the two literals `true` and `false`.
+
+    To store objects in C++, a type is defined by the template parameter @a
+    BooleanType which chooses the type to use.
+
+    #### Default type
+
+    With the default values for @a BooleanType (`bool`), the default value for
+    @a boolean_t is:
+
+    @code {.cpp}
+    bool
+    @endcode
+
+    #### Storage
+
+    Boolean values are stored directly inside a @ref basic_json type.
+
+    @since version 1.0.0
+    */
+    using boolean_t = BooleanType;
+
+    /*!
+    @brief a type for a number (integer)
+
+    [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows:
+    > The representation of numbers is similar to that used in most
+    > programming languages. A number is represented in base 10 using decimal
+    > digits. It contains an integer component that may be prefixed with an
+    > optional minus sign, which may be followed by a fraction part and/or an
+    > exponent part. Leading zeros are not allowed. (...) Numeric values that
+    > cannot be represented in the grammar below (such as Infinity and NaN)
+    > are not permitted.
+
+    This description includes both integer and floating-point numbers.
+    However, C++ allows more precise storage if it is known whether the number
+    is a signed integer, an unsigned integer or a floating-point number.
+    Therefore, three different types, @ref number_integer_t, @ref
+    number_unsigned_t and @ref number_float_t are used.
+
+    To store integer numbers in C++, a type is defined by the template
+    parameter @a NumberIntegerType which chooses the type to use.
+
+    #### Default type
+
+    With the default values for @a NumberIntegerType (`int64_t`), the default
+    value for @a number_integer_t is:
+
+    @code {.cpp}
+    int64_t
+    @endcode
+
+    #### Default behavior
+
+    - The restrictions about leading zeros is not enforced in C++. Instead,
+      leading zeros in integer literals lead to an interpretation as octal
+      number. Internally, the value will be stored as decimal number. For
+      instance, the C++ integer literal `010` will be serialized to `8`.
+      During deserialization, leading zeros yield an error.
+    - Not-a-number (NaN) values will be serialized to `null`.
+
+    #### Limits
+
+    [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+    > An implementation may set limits on the range and precision of numbers.
+
+    When the default type is used, the maximal integer number that can be
+    stored is `9223372036854775807` (INT64_MAX) and the minimal integer number
+    that can be stored is `-9223372036854775808` (INT64_MIN). Integer numbers
+    that are out of range will yield over/underflow when used in a
+    constructor. During deserialization, too large or small integer numbers
+    will be automatically be stored as @ref number_unsigned_t or @ref
+    number_float_t.
+
+    [RFC 7159](http://rfc7159.net/rfc7159) further states:
+    > Note that when such software is used, numbers that are integers and are
+    > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense
+    > that implementations will agree exactly on their numeric values.
+
+    As this range is a subrange of the exactly supported range [INT64_MIN,
+    INT64_MAX], this class's integer type is interoperable.
+
+    #### Storage
+
+    Integer number values are stored directly inside a @ref basic_json type.
+
+    @sa @ref number_float_t -- type for number values (floating-point)
+
+    @sa @ref number_unsigned_t -- type for number values (unsigned integer)
+
+    @since version 1.0.0
+    */
+    using number_integer_t = NumberIntegerType;
+
+    /*!
+    @brief a type for a number (unsigned)
+
+    [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows:
+    > The representation of numbers is similar to that used in most
+    > programming languages. A number is represented in base 10 using decimal
+    > digits. It contains an integer component that may be prefixed with an
+    > optional minus sign, which may be followed by a fraction part and/or an
+    > exponent part. Leading zeros are not allowed. (...) Numeric values that
+    > cannot be represented in the grammar below (such as Infinity and NaN)
+    > are not permitted.
+
+    This description includes both integer and floating-point numbers.
+    However, C++ allows more precise storage if it is known whether the number
+    is a signed integer, an unsigned integer or a floating-point number.
+    Therefore, three different types, @ref number_integer_t, @ref
+    number_unsigned_t and @ref number_float_t are used.
+
+    To store unsigned integer numbers in C++, a type is defined by the
+    template parameter @a NumberUnsignedType which chooses the type to use.
+
+    #### Default type
+
+    With the default values for @a NumberUnsignedType (`uint64_t`), the
+    default value for @a number_unsigned_t is:
+
+    @code {.cpp}
+    uint64_t
+    @endcode
+
+    #### Default behavior
+
+    - The restrictions about leading zeros is not enforced in C++. Instead,
+      leading zeros in integer literals lead to an interpretation as octal
+      number. Internally, the value will be stored as decimal number. For
+      instance, the C++ integer literal `010` will be serialized to `8`.
+      During deserialization, leading zeros yield an error.
+    - Not-a-number (NaN) values will be serialized to `null`.
+
+    #### Limits
+
+    [RFC 7159](http://rfc7159.net/rfc7159) specifies:
+    > An implementation may set limits on the range and precision of numbers.
+
+    When the default type is used, the maximal integer number that can be
+    stored is `18446744073709551615` (UINT64_MAX) and the minimal integer
+    number that can be stored is `0`. Integer numbers that are out of range
+    will yield over/underflow when used in a constructor. During
+    deserialization, too large or small integer numbers will be automatically
+    be stored as @ref number_integer_t or @ref number_float_t.
+
+    [RFC 7159](http://rfc7159.net/rfc7159) further states:
+    > Note that when such software is used, numbers that are integers and are
+    > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense
+    > that implementations will agree exactly on their numeric values.
+
+    As this range is a subrange (when considered in conjunction with the
+    number_integer_t type) of the exactly supported range [0, UINT64_MAX],
+    this class's integer type is interoperable.
+
+    #### Storage
+
+    Integer number values are stored directly inside a @ref basic_json type.
+
+    @sa @ref number_float_t -- type for number values (floating-point)
+    @sa @ref number_integer_t -- type for number values (integer)
+
+    @since version 2.0.0
+    */
+    using number_unsigned_t = NumberUnsignedType;
+
+    /*!
+    @brief a type for a number (floating-point)
+
+    [RFC 7159](http://rfc7159.net/rfc7159) describes numbers as follows:
+    > The representation of numbers is similar to that used in most
+    > programming languages. A number is represented in base 10 using decimal
+    > digits. It contains an integer component that may be prefixed with an
+    > optional minus sign, which may be followed by a fraction part and/or an
+    > exponent part. Leading zeros are not allowed. (...) Numeric values that
+    > cannot be represented in the grammar below (such as Infinity and NaN)
+    > are not permitted.
+
+    This description includes both integer and floating-point numbers.
+    However, C++ allows more precise storage if it is known whether the number
+    is a signed integer, an unsigned integer or a floating-point number.
+    Therefore, three different types, @ref number_integer_t, @ref
+    number_unsigned_t and @ref number_float_t are used.
+
+    To store floating-point numbers in C++, a type is defined by the template
+    parameter @a NumberFloatType which chooses the type to use.
+
+    #### Default type
+
+    With the default values for @a NumberFloatType (`double`), the default
+    value for @a number_float_t is:
+
+    @code {.cpp}
+    double
+    @endcode
+
+    #### Default behavior
+
+    - The restrictions about leading zeros is not enforced in C++. Instead,
+      leading zeros in floating-point literals will be ignored. Internally,
+      the value will be stored as decimal number. For instance, the C++
+      floating-point literal `01.2` will be serialized to `1.2`. During
+      deserialization, leading zeros yield an error.
+    - Not-a-number (NaN) values will be serialized to `null`.
+
+    #### Limits
+
+    [RFC 7159](http://rfc7159.net/rfc7159) states:
+    > This specification allows implementations to set limits on the range and
+    > precision of numbers accepted. Since software that implements IEEE
+    > 754-2008 binary64 (double precision) numbers is generally available and
+    > widely used, good interoperability can be achieved by implementations
+    > that expect no more precision or range than these provide, in the sense
+    > that implementations will approximate JSON numbers within the expected
+    > precision.
+
+    This implementation does exactly follow this approach, as it uses double
+    precision floating-point numbers. Note values smaller than
+    `-1.79769313486232e+308` and values greater than `1.79769313486232e+308`
+    will be stored as NaN internally and be serialized to `null`.
+
+    #### Storage
+
+    Floating-point number values are stored directly inside a @ref basic_json
+    type.
+
+    @sa @ref number_integer_t -- type for number values (integer)
+
+    @sa @ref number_unsigned_t -- type for number values (unsigned integer)
+
+    @since version 1.0.0
+    */
+    using number_float_t = NumberFloatType;
+
+    /// @}
+
+  private:
+
+    /// helper for exception-safe object creation
+    template<typename T, typename... Args>
+    static T* create(Args&& ... args)
+    {
+        AllocatorType<T> alloc;
+        using AllocatorTraits = std::allocator_traits<AllocatorType<T>>;
+
+        auto deleter = [&](T * object)
+        {
+            AllocatorTraits::deallocate(alloc, object, 1);
+        };
+        std::unique_ptr<T, decltype(deleter)> object(AllocatorTraits::allocate(alloc, 1), deleter);
+        AllocatorTraits::construct(alloc, object.get(), std::forward<Args>(args)...);
+        assert(object != nullptr);
+        return object.release();
+    }
+
+    ////////////////////////
+    // JSON value storage //
+    ////////////////////////
+
+    /*!
+    @brief a JSON value
+
+    The actual storage for a JSON value of the @ref basic_json class. This
+    union combines the different storage types for the JSON value types
+    defined in @ref value_t.
+
+    JSON type | value_t type    | used type
+    --------- | --------------- | ------------------------
+    object    | object          | pointer to @ref object_t
+    array     | array           | pointer to @ref array_t
+    string    | string          | pointer to @ref string_t
+    boolean   | boolean         | @ref boolean_t
+    number    | number_integer  | @ref number_integer_t
+    number    | number_unsigned | @ref number_unsigned_t
+    number    | number_float    | @ref number_float_t
+    null      | null            | *no value is stored*
+
+    @note Variable-length types (objects, arrays, and strings) are stored as
+    pointers. The size of the union should not exceed 64 bits if the default
+    value types are used.
+
+    @since version 1.0.0
+    */
+    union json_value
+    {
+        /// object (stored with pointer to save storage)
+        object_t* object;
+        /// array (stored with pointer to save storage)
+        array_t* array;
+        /// string (stored with pointer to save storage)
+        string_t* string;
+        /// boolean
+        boolean_t boolean;
+        /// number (integer)
+        number_integer_t number_integer;
+        /// number (unsigned integer)
+        number_unsigned_t number_unsigned;
+        /// number (floating-point)
+        number_float_t number_float;
+
+        /// default constructor (for null values)
+        json_value() = default;
+        /// constructor for booleans
+        json_value(boolean_t v) noexcept : boolean(v) {}
+        /// constructor for numbers (integer)
+        json_value(number_integer_t v) noexcept : number_integer(v) {}
+        /// constructor for numbers (unsigned)
+        json_value(number_unsigned_t v) noexcept : number_unsigned(v) {}
+        /// constructor for numbers (floating-point)
+        json_value(number_float_t v) noexcept : number_float(v) {}
+        /// constructor for empty values of a given type
+        json_value(value_t t)
+        {
+            switch (t)
+            {
+                case value_t::object:
+                {
+                    object = create<object_t>();
+                    break;
+                }
+
+                case value_t::array:
+                {
+                    array = create<array_t>();
+                    break;
+                }
+
+                case value_t::string:
+                {
+                    string = create<string_t>("");
+                    break;
+                }
+
+                case value_t::boolean:
+                {
+                    boolean = boolean_t(false);
+                    break;
+                }
+
+                case value_t::number_integer:
+                {
+                    number_integer = number_integer_t(0);
+                    break;
+                }
+
+                case value_t::number_unsigned:
+                {
+                    number_unsigned = number_unsigned_t(0);
+                    break;
+                }
+
+                case value_t::number_float:
+                {
+                    number_float = number_float_t(0.0);
+                    break;
+                }
+
+                case value_t::null:
+                {
+                    object = nullptr;  // silence warning, see #821
+                    break;
+                }
+
+                default:
+                {
+                    object = nullptr;  // silence warning, see #821
+                    if (JSON_UNLIKELY(t == value_t::null))
+                    {
+                        JSON_THROW(other_error::create(500, "961c151d2e87f2686a955a9be24d316f1362bf21 3.5.0")); // LCOV_EXCL_LINE
+                    }
+                    break;
+                }
+            }
+        }
+
+        /// constructor for strings
+        json_value(const string_t& value)
+        {
+            string = create<string_t>(value);
+        }
+
+        /// constructor for rvalue strings
+        json_value(string_t&& value)
+        {
+            string = create<string_t>(std::move(value));
+        }
+
+        /// constructor for objects
+        json_value(const object_t& value)
+        {
+            object = create<object_t>(value);
+        }
+
+        /// constructor for rvalue objects
+        json_value(object_t&& value)
+        {
+            object = create<object_t>(std::move(value));
+        }
+
+        /// constructor for arrays
+        json_value(const array_t& value)
+        {
+            array = create<array_t>(value);
+        }
+
+        /// constructor for rvalue arrays
+        json_value(array_t&& value)
+        {
+            array = create<array_t>(std::move(value));
+        }
+
+        void destroy(value_t t) noexcept
+        {
+            switch (t)
+            {
+                case value_t::object:
+                {
+                    AllocatorType<object_t> alloc;
+                    std::allocator_traits<decltype(alloc)>::destroy(alloc, object);
+                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, object, 1);
+                    break;
+                }
+
+                case value_t::array:
+                {
+                    AllocatorType<array_t> alloc;
+                    std::allocator_traits<decltype(alloc)>::destroy(alloc, array);
+                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, array, 1);
+                    break;
+                }
+
+                case value_t::string:
+                {
+                    AllocatorType<string_t> alloc;
+                    std::allocator_traits<decltype(alloc)>::destroy(alloc, string);
+                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, string, 1);
+                    break;
+                }
+
+                default:
+                {
+                    break;
+                }
+            }
+        }
+    };
+
+    /*!
+    @brief checks the class invariants
+
+    This function asserts the class invariants. It needs to be called at the
+    end of every constructor to make sure that created objects respect the
+    invariant. Furthermore, it has to be called each time the type of a JSON
+    value is changed, because the invariant expresses a relationship between
+    @a m_type and @a m_value.
+    */
+    void assert_invariant() const noexcept
+    {
+        assert(m_type != value_t::object or m_value.object != nullptr);
+        assert(m_type != value_t::array or m_value.array != nullptr);
+        assert(m_type != value_t::string or m_value.string != nullptr);
+    }
+
+  public:
+    //////////////////////////
+    // JSON parser callback //
+    //////////////////////////
+
+    /*!
+    @brief parser event types
+
+    The parser callback distinguishes the following events:
+    - `object_start`: the parser read `{` and started to process a JSON object
+    - `key`: the parser read a key of a value in an object
+    - `object_end`: the parser read `}` and finished processing a JSON object
+    - `array_start`: the parser read `[` and started to process a JSON array
+    - `array_end`: the parser read `]` and finished processing a JSON array
+    - `value`: the parser finished reading a JSON value
+
+    @image html callback_events.png "Example when certain parse events are triggered"
+
+    @sa @ref parser_callback_t for more information and examples
+    */
+    using parse_event_t = typename parser::parse_event_t;
+
+    /*!
+    @brief per-element parser callback type
+
+    With a parser callback function, the result of parsing a JSON text can be
+    influenced. When passed to @ref parse, it is called on certain events
+    (passed as @ref parse_event_t via parameter @a event) with a set recursion
+    depth @a depth and context JSON value @a parsed. The return value of the
+    callback function is a boolean indicating whether the element that emitted
+    the callback shall be kept or not.
+
+    We distinguish six scenarios (determined by the event type) in which the
+    callback function can be called. The following table describes the values
+    of the parameters @a depth, @a event, and @a parsed.
+
+    parameter @a event | description | parameter @a depth | parameter @a parsed
+    ------------------ | ----------- | ------------------ | -------------------
+    parse_event_t::object_start | the parser read `{` and started to process a JSON object | depth of the parent of the JSON object | a JSON value with type discarded
+    parse_event_t::key | the parser read a key of a value in an object | depth of the currently parsed JSON object | a JSON string containing the key
+    parse_event_t::object_end | the parser read `}` and finished processing a JSON object | depth of the parent of the JSON object | the parsed JSON object
+    parse_event_t::array_start | the parser read `[` and started to process a JSON array | depth of the parent of the JSON array | a JSON value with type discarded
+    parse_event_t::array_end | the parser read `]` and finished processing a JSON array | depth of the parent of the JSON array | the parsed JSON array
+    parse_event_t::value | the parser finished reading a JSON value | depth of the value | the parsed JSON value
+
+    @image html callback_events.png "Example when certain parse events are triggered"
+
+    Discarding a value (i.e., returning `false`) has different effects
+    depending on the context in which function was called:
+
+    - Discarded values in structured types are skipped. That is, the parser
+      will behave as if the discarded value was never read.
+    - In case a value outside a structured type is skipped, it is replaced
+      with `null`. This case happens if the top-level element is skipped.
+
+    @param[in] depth  the depth of the recursion during parsing
+
+    @param[in] event  an event of type parse_event_t indicating the context in
+    the callback function has been called
+
+    @param[in,out] parsed  the current intermediate parse result; note that
+    writing to this value has no effect for parse_event_t::key events
+
+    @return Whether the JSON value which called the function during parsing
+    should be kept (`true`) or not (`false`). In the latter case, it is either
+    skipped completely or replaced by an empty discarded object.
+
+    @sa @ref parse for examples
+
+    @since version 1.0.0
+    */
+    using parser_callback_t = typename parser::parser_callback_t;
+
+    //////////////////
+    // constructors //
+    //////////////////
+
+    /// @name constructors and destructors
+    /// Constructors of class @ref basic_json, copy/move constructor, copy
+    /// assignment, static functions creating objects, and the destructor.
+    /// @{
+
+    /*!
+    @brief create an empty value with a given type
+
+    Create an empty JSON value with a given type. The value will be default
+    initialized with an empty value which depends on the type:
+
+    Value type  | initial value
+    ----------- | -------------
+    null        | `null`
+    boolean     | `false`
+    string      | `""`
+    number      | `0`
+    object      | `{}`
+    array       | `[]`
+
+    @param[in] v  the type of the value to create
+
+    @complexity Constant.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @liveexample{The following code shows the constructor for different @ref
+    value_t values,basic_json__value_t}
+
+    @sa @ref clear() -- restores the postcondition of this constructor
+
+    @since version 1.0.0
+    */
+    basic_json(const value_t v)
+        : m_type(v), m_value(v)
+    {
+        assert_invariant();
+    }
+
+    /*!
+    @brief create a null object
+
+    Create a `null` JSON value. It either takes a null pointer as parameter
+    (explicitly creating `null`) or no parameter (implicitly creating `null`).
+    The passed null pointer itself is not read -- it is only used to choose
+    the right constructor.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this constructor never throws
+    exceptions.
+
+    @liveexample{The following code shows the constructor with and without a
+    null pointer parameter.,basic_json__nullptr_t}
+
+    @since version 1.0.0
+    */
+    basic_json(std::nullptr_t = nullptr) noexcept
+        : basic_json(value_t::null)
+    {
+        assert_invariant();
+    }
+
+    /*!
+    @brief create a JSON value
+
+    This is a "catch all" constructor for all compatible JSON types; that is,
+    types for which a `to_json()` method exists. The constructor forwards the
+    parameter @a val to that method (to `json_serializer<U>::to_json` method
+    with `U = uncvref_t<CompatibleType>`, to be exact).
+
+    Template type @a CompatibleType includes, but is not limited to, the
+    following types:
+    - **arrays**: @ref array_t and all kinds of compatible containers such as
+      `std::vector`, `std::deque`, `std::list`, `std::forward_list`,
+      `std::array`, `std::valarray`, `std::set`, `std::unordered_set`,
+      `std::multiset`, and `std::unordered_multiset` with a `value_type` from
+      which a @ref basic_json value can be constructed.
+    - **objects**: @ref object_t and all kinds of compatible associative
+      containers such as `std::map`, `std::unordered_map`, `std::multimap`,
+      and `std::unordered_multimap` with a `key_type` compatible to
+      @ref string_t and a `value_type` from which a @ref basic_json value can
+      be constructed.
+    - **strings**: @ref string_t, string literals, and all compatible string
+      containers can be used.
+    - **numbers**: @ref number_integer_t, @ref number_unsigned_t,
+      @ref number_float_t, and all convertible number types such as `int`,
+      `size_t`, `int64_t`, `float` or `double` can be used.
+    - **boolean**: @ref boolean_t / `bool` can be used.
+
+    See the examples below.
+
+    @tparam CompatibleType a type such that:
+    - @a CompatibleType is not derived from `std::istream`,
+    - @a CompatibleType is not @ref basic_json (to avoid hijacking copy/move
+         constructors),
+    - @a CompatibleType is not a different @ref basic_json type (i.e. with different template arguments)
+    - @a CompatibleType is not a @ref basic_json nested type (e.g.,
+         @ref json_pointer, @ref iterator, etc ...)
+    - @ref @ref json_serializer<U> has a
+         `to_json(basic_json_t&, CompatibleType&&)` method
+
+    @tparam U = `uncvref_t<CompatibleType>`
+
+    @param[in] val the value to be forwarded to the respective constructor
+
+    @complexity Usually linear in the size of the passed @a val, also
+                depending on the implementation of the called `to_json()`
+                method.
+
+    @exceptionsafety Depends on the called constructor. For types directly
+    supported by the library (i.e., all types for which no `to_json()` function
+    was provided), strong guarantee holds: if an exception is thrown, there are
+    no changes to any JSON value.
+
+    @liveexample{The following code shows the constructor with several
+    compatible types.,basic_json__CompatibleType}
+
+    @since version 2.1.0
+    */
+    template <typename CompatibleType,
+              typename U = detail::uncvref_t<CompatibleType>,
+              detail::enable_if_t<
+                  not detail::is_basic_json<U>::value and detail::is_compatible_type<basic_json_t, U>::value, int> = 0>
+    basic_json(CompatibleType && val) noexcept(noexcept(
+                JSONSerializer<U>::to_json(std::declval<basic_json_t&>(),
+                                           std::forward<CompatibleType>(val))))
+    {
+        JSONSerializer<U>::to_json(*this, std::forward<CompatibleType>(val));
+        assert_invariant();
+    }
+
+    /*!
+    @brief create a JSON value from an existing one
+
+    This is a constructor for existing @ref basic_json types.
+    It does not hijack copy/move constructors, since the parameter has different
+    template arguments than the current ones.
+
+    The constructor tries to convert the internal @ref m_value of the parameter.
+
+    @tparam BasicJsonType a type such that:
+    - @a BasicJsonType is a @ref basic_json type.
+    - @a BasicJsonType has different template arguments than @ref basic_json_t.
+
+    @param[in] val the @ref basic_json value to be converted.
+
+    @complexity Usually linear in the size of the passed @a val, also
+                depending on the implementation of the called `to_json()`
+                method.
+
+    @exceptionsafety Depends on the called constructor. For types directly
+    supported by the library (i.e., all types for which no `to_json()` function
+    was provided), strong guarantee holds: if an exception is thrown, there are
+    no changes to any JSON value.
+
+    @since version 3.2.0
+    */
+    template <typename BasicJsonType,
+              detail::enable_if_t<
+                  detail::is_basic_json<BasicJsonType>::value and not std::is_same<basic_json, BasicJsonType>::value, int> = 0>
+    basic_json(const BasicJsonType& val)
+    {
+        using other_boolean_t = typename BasicJsonType::boolean_t;
+        using other_number_float_t = typename BasicJsonType::number_float_t;
+        using other_number_integer_t = typename BasicJsonType::number_integer_t;
+        using other_number_unsigned_t = typename BasicJsonType::number_unsigned_t;
+        using other_string_t = typename BasicJsonType::string_t;
+        using other_object_t = typename BasicJsonType::object_t;
+        using other_array_t = typename BasicJsonType::array_t;
+
+        switch (val.type())
+        {
+            case value_t::boolean:
+                JSONSerializer<other_boolean_t>::to_json(*this, val.template get<other_boolean_t>());
+                break;
+            case value_t::number_float:
+                JSONSerializer<other_number_float_t>::to_json(*this, val.template get<other_number_float_t>());
+                break;
+            case value_t::number_integer:
+                JSONSerializer<other_number_integer_t>::to_json(*this, val.template get<other_number_integer_t>());
+                break;
+            case value_t::number_unsigned:
+                JSONSerializer<other_number_unsigned_t>::to_json(*this, val.template get<other_number_unsigned_t>());
+                break;
+            case value_t::string:
+                JSONSerializer<other_string_t>::to_json(*this, val.template get_ref<const other_string_t&>());
+                break;
+            case value_t::object:
+                JSONSerializer<other_object_t>::to_json(*this, val.template get_ref<const other_object_t&>());
+                break;
+            case value_t::array:
+                JSONSerializer<other_array_t>::to_json(*this, val.template get_ref<const other_array_t&>());
+                break;
+            case value_t::null:
+                *this = nullptr;
+                break;
+            case value_t::discarded:
+                m_type = value_t::discarded;
+                break;
+        }
+        assert_invariant();
+    }
+
+    /*!
+    @brief create a container (array or object) from an initializer list
+
+    Creates a JSON value of type array or object from the passed initializer
+    list @a init. In case @a type_deduction is `true` (default), the type of
+    the JSON value to be created is deducted from the initializer list @a init
+    according to the following rules:
+
+    1. If the list is empty, an empty JSON object value `{}` is created.
+    2. If the list consists of pairs whose first element is a string, a JSON
+       object value is created where the first elements of the pairs are
+       treated as keys and the second elements are as values.
+    3. In all other cases, an array is created.
+
+    The rules aim to create the best fit between a C++ initializer list and
+    JSON values. The rationale is as follows:
+
+    1. The empty initializer list is written as `{}` which is exactly an empty
+       JSON object.
+    2. C++ has no way of describing mapped types other than to list a list of
+       pairs. As JSON requires that keys must be of type string, rule 2 is the
+       weakest constraint one can pose on initializer lists to interpret them
+       as an object.
+    3. In all other cases, the initializer list could not be interpreted as
+       JSON object type, so interpreting it as JSON array type is safe.
+
+    With the rules described above, the following JSON values cannot be
+    expressed by an initializer list:
+
+    - the empty array (`[]`): use @ref array(initializer_list_t)
+      with an empty initializer list in this case
+    - arrays whose elements satisfy rule 2: use @ref
+      array(initializer_list_t) with the same initializer list
+      in this case
+
+    @note When used without parentheses around an empty initializer list, @ref
+    basic_json() is called instead of this function, yielding the JSON null
+    value.
+
+    @param[in] init  initializer list with JSON values
+
+    @param[in] type_deduction internal parameter; when set to `true`, the type
+    of the JSON value is deducted from the initializer list @a init; when set
+    to `false`, the type provided via @a manual_type is forced. This mode is
+    used by the functions @ref array(initializer_list_t) and
+    @ref object(initializer_list_t).
+
+    @param[in] manual_type internal parameter; when @a type_deduction is set
+    to `false`, the created JSON value will use the provided type (only @ref
+    value_t::array and @ref value_t::object are valid); when @a type_deduction
+    is set to `true`, this parameter has no effect
+
+    @throw type_error.301 if @a type_deduction is `false`, @a manual_type is
+    `value_t::object`, but @a init contains an element which is not a pair
+    whose first element is a string. In this case, the constructor could not
+    create an object. If @a type_deduction would have be `true`, an array
+    would have been created. See @ref object(initializer_list_t)
+    for an example.
+
+    @complexity Linear in the size of the initializer list @a init.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @liveexample{The example below shows how JSON values are created from
+    initializer lists.,basic_json__list_init_t}
+
+    @sa @ref array(initializer_list_t) -- create a JSON array
+    value from an initializer list
+    @sa @ref object(initializer_list_t) -- create a JSON object
+    value from an initializer list
+
+    @since version 1.0.0
+    */
+    basic_json(initializer_list_t init,
+               bool type_deduction = true,
+               value_t manual_type = value_t::array)
+    {
+        // check if each element is an array with two elements whose first
+        // element is a string
+        bool is_an_object = std::all_of(init.begin(), init.end(),
+                                        [](const detail::json_ref<basic_json>& element_ref)
+        {
+            return (element_ref->is_array() and element_ref->size() == 2 and (*element_ref)[0].is_string());
+        });
+
+        // adjust type if type deduction is not wanted
+        if (not type_deduction)
+        {
+            // if array is wanted, do not create an object though possible
+            if (manual_type == value_t::array)
+            {
+                is_an_object = false;
+            }
+
+            // if object is wanted but impossible, throw an exception
+            if (JSON_UNLIKELY(manual_type == value_t::object and not is_an_object))
+            {
+                JSON_THROW(type_error::create(301, "cannot create object from initializer list"));
+            }
+        }
+
+        if (is_an_object)
+        {
+            // the initializer list is a list of pairs -> create object
+            m_type = value_t::object;
+            m_value = value_t::object;
+
+            std::for_each(init.begin(), init.end(), [this](const detail::json_ref<basic_json>& element_ref)
+            {
+                auto element = element_ref.moved_or_copied();
+                m_value.object->emplace(
+                    std::move(*((*element.m_value.array)[0].m_value.string)),
+                    std::move((*element.m_value.array)[1]));
+            });
+        }
+        else
+        {
+            // the initializer list describes an array -> create array
+            m_type = value_t::array;
+            m_value.array = create<array_t>(init.begin(), init.end());
+        }
+
+        assert_invariant();
+    }
+
+    /*!
+    @brief explicitly create an array from an initializer list
+
+    Creates a JSON array value from a given initializer list. That is, given a
+    list of values `a, b, c`, creates the JSON value `[a, b, c]`. If the
+    initializer list is empty, the empty array `[]` is created.
+
+    @note This function is only needed to express two edge cases that cannot
+    be realized with the initializer list constructor (@ref
+    basic_json(initializer_list_t, bool, value_t)). These cases
+    are:
+    1. creating an array whose elements are all pairs whose first element is a
+    string -- in this case, the initializer list constructor would create an
+    object, taking the first elements as keys
+    2. creating an empty array -- passing the empty initializer list to the
+    initializer list constructor yields an empty object
+
+    @param[in] init  initializer list with JSON values to create an array from
+    (optional)
+
+    @return JSON array value
+
+    @complexity Linear in the size of @a init.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @liveexample{The following code shows an example for the `array`
+    function.,array}
+
+    @sa @ref basic_json(initializer_list_t, bool, value_t) --
+    create a JSON value from an initializer list
+    @sa @ref object(initializer_list_t) -- create a JSON object
+    value from an initializer list
+
+    @since version 1.0.0
+    */
+    static basic_json array(initializer_list_t init = {})
+    {
+        return basic_json(init, false, value_t::array);
+    }
+
+    /*!
+    @brief explicitly create an object from an initializer list
+
+    Creates a JSON object value from a given initializer list. The initializer
+    lists elements must be pairs, and their first elements must be strings. If
+    the initializer list is empty, the empty object `{}` is created.
+
+    @note This function is only added for symmetry reasons. In contrast to the
+    related function @ref array(initializer_list_t), there are
+    no cases which can only be expressed by this function. That is, any
+    initializer list @a init can also be passed to the initializer list
+    constructor @ref basic_json(initializer_list_t, bool, value_t).
+
+    @param[in] init  initializer list to create an object from (optional)
+
+    @return JSON object value
+
+    @throw type_error.301 if @a init is not a list of pairs whose first
+    elements are strings. In this case, no object can be created. When such a
+    value is passed to @ref basic_json(initializer_list_t, bool, value_t),
+    an array would have been created from the passed initializer list @a init.
+    See example below.
+
+    @complexity Linear in the size of @a init.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @liveexample{The following code shows an example for the `object`
+    function.,object}
+
+    @sa @ref basic_json(initializer_list_t, bool, value_t) --
+    create a JSON value from an initializer list
+    @sa @ref array(initializer_list_t) -- create a JSON array
+    value from an initializer list
+
+    @since version 1.0.0
+    */
+    static basic_json object(initializer_list_t init = {})
+    {
+        return basic_json(init, false, value_t::object);
+    }
+
+    /*!
+    @brief construct an array with count copies of given value
+
+    Constructs a JSON array value by creating @a cnt copies of a passed value.
+    In case @a cnt is `0`, an empty array is created.
+
+    @param[in] cnt  the number of JSON copies of @a val to create
+    @param[in] val  the JSON value to copy
+
+    @post `std::distance(begin(),end()) == cnt` holds.
+
+    @complexity Linear in @a cnt.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @liveexample{The following code shows examples for the @ref
+    basic_json(size_type\, const basic_json&)
+    constructor.,basic_json__size_type_basic_json}
+
+    @since version 1.0.0
+    */
+    basic_json(size_type cnt, const basic_json& val)
+        : m_type(value_t::array)
+    {
+        m_value.array = create<array_t>(cnt, val);
+        assert_invariant();
+    }
+
+    /*!
+    @brief construct a JSON container given an iterator range
+
+    Constructs the JSON value with the contents of the range `[first, last)`.
+    The semantics depends on the different types a JSON value can have:
+    - In case of a null type, invalid_iterator.206 is thrown.
+    - In case of other primitive types (number, boolean, or string), @a first
+      must be `begin()` and @a last must be `end()`. In this case, the value is
+      copied. Otherwise, invalid_iterator.204 is thrown.
+    - In case of structured types (array, object), the constructor behaves as
+      similar versions for `std::vector` or `std::map`; that is, a JSON array
+      or object is constructed from the values in the range.
+
+    @tparam InputIT an input iterator type (@ref iterator or @ref
+    const_iterator)
+
+    @param[in] first begin of the range to copy from (included)
+    @param[in] last end of the range to copy from (excluded)
+
+    @pre Iterators @a first and @a last must be initialized. **This
+         precondition is enforced with an assertion (see warning).** If
+         assertions are switched off, a violation of this precondition yields
+         undefined behavior.
+
+    @pre Range `[first, last)` is valid. Usually, this precondition cannot be
+         checked efficiently. Only certain edge cases are detected; see the
+         description of the exceptions below. A violation of this precondition
+         yields undefined behavior.
+
+    @warning A precondition is enforced with a runtime assertion that will
+             result in calling `std::abort` if this precondition is not met.
+             Assertions can be disabled by defining `NDEBUG` at compile time.
+             See https://en.cppreference.com/w/cpp/error/assert for more
+             information.
+
+    @throw invalid_iterator.201 if iterators @a first and @a last are not
+    compatible (i.e., do not belong to the same JSON value). In this case,
+    the range `[first, last)` is undefined.
+    @throw invalid_iterator.204 if iterators @a first and @a last belong to a
+    primitive type (number, boolean, or string), but @a first does not point
+    to the first element any more. In this case, the range `[first, last)` is
+    undefined. See example code below.
+    @throw invalid_iterator.206 if iterators @a first and @a last belong to a
+    null value. In this case, the range `[first, last)` is undefined.
+
+    @complexity Linear in distance between @a first and @a last.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @liveexample{The example below shows several ways to create JSON values by
+    specifying a subrange with iterators.,basic_json__InputIt_InputIt}
+
+    @since version 1.0.0
+    */
+    template<class InputIT, typename std::enable_if<
+                 std::is_same<InputIT, typename basic_json_t::iterator>::value or
+                 std::is_same<InputIT, typename basic_json_t::const_iterator>::value, int>::type = 0>
+    basic_json(InputIT first, InputIT last)
+    {
+        assert(first.m_object != nullptr);
+        assert(last.m_object != nullptr);
+
+        // make sure iterator fits the current value
+        if (JSON_UNLIKELY(first.m_object != last.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(201, "iterators are not compatible"));
+        }
+
+        // copy type from first iterator
+        m_type = first.m_object->m_type;
+
+        // check if iterator range is complete for primitive values
+        switch (m_type)
+        {
+            case value_t::boolean:
+            case value_t::number_float:
+            case value_t::number_integer:
+            case value_t::number_unsigned:
+            case value_t::string:
+            {
+                if (JSON_UNLIKELY(not first.m_it.primitive_iterator.is_begin()
+                                  or not last.m_it.primitive_iterator.is_end()))
+                {
+                    JSON_THROW(invalid_iterator::create(204, "iterators out of range"));
+                }
+                break;
+            }
+
+            default:
+                break;
+        }
+
+        switch (m_type)
+        {
+            case value_t::number_integer:
+            {
+                m_value.number_integer = first.m_object->m_value.number_integer;
+                break;
+            }
+
+            case value_t::number_unsigned:
+            {
+                m_value.number_unsigned = first.m_object->m_value.number_unsigned;
+                break;
+            }
+
+            case value_t::number_float:
+            {
+                m_value.number_float = first.m_object->m_value.number_float;
+                break;
+            }
+
+            case value_t::boolean:
+            {
+                m_value.boolean = first.m_object->m_value.boolean;
+                break;
+            }
+
+            case value_t::string:
+            {
+                m_value = *first.m_object->m_value.string;
+                break;
+            }
+
+            case value_t::object:
+            {
+                m_value.object = create<object_t>(first.m_it.object_iterator,
+                                                  last.m_it.object_iterator);
+                break;
+            }
+
+            case value_t::array:
+            {
+                m_value.array = create<array_t>(first.m_it.array_iterator,
+                                                last.m_it.array_iterator);
+                break;
+            }
+
+            default:
+                JSON_THROW(invalid_iterator::create(206, "cannot construct with iterators from " +
+                                                    std::string(first.m_object->type_name())));
+        }
+
+        assert_invariant();
+    }
+
+
+    ///////////////////////////////////////
+    // other constructors and destructor //
+    ///////////////////////////////////////
+
+    /// @private
+    basic_json(const detail::json_ref<basic_json>& ref)
+        : basic_json(ref.moved_or_copied())
+    {}
+
+    /*!
+    @brief copy constructor
+
+    Creates a copy of a given JSON value.
+
+    @param[in] other  the JSON value to copy
+
+    @post `*this == other`
+
+    @complexity Linear in the size of @a other.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes to any JSON value.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is linear.
+    - As postcondition, it holds: `other == basic_json(other)`.
+
+    @liveexample{The following code shows an example for the copy
+    constructor.,basic_json__basic_json}
+
+    @since version 1.0.0
+    */
+    basic_json(const basic_json& other)
+        : m_type(other.m_type)
+    {
+        // check of passed value is valid
+        other.assert_invariant();
+
+        switch (m_type)
+        {
+            case value_t::object:
+            {
+                m_value = *other.m_value.object;
+                break;
+            }
+
+            case value_t::array:
+            {
+                m_value = *other.m_value.array;
+                break;
+            }
+
+            case value_t::string:
+            {
+                m_value = *other.m_value.string;
+                break;
+            }
+
+            case value_t::boolean:
+            {
+                m_value = other.m_value.boolean;
+                break;
+            }
+
+            case value_t::number_integer:
+            {
+                m_value = other.m_value.number_integer;
+                break;
+            }
+
+            case value_t::number_unsigned:
+            {
+                m_value = other.m_value.number_unsigned;
+                break;
+            }
+
+            case value_t::number_float:
+            {
+                m_value = other.m_value.number_float;
+                break;
+            }
+
+            default:
+                break;
+        }
+
+        assert_invariant();
+    }
+
+    /*!
+    @brief move constructor
+
+    Move constructor. Constructs a JSON value with the contents of the given
+    value @a other using move semantics. It "steals" the resources from @a
+    other and leaves it as JSON null value.
+
+    @param[in,out] other  value to move to this object
+
+    @post `*this` has the same value as @a other before the call.
+    @post @a other is a JSON null value.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this constructor never throws
+    exceptions.
+
+    @requirement This function helps `basic_json` satisfying the
+    [MoveConstructible](https://en.cppreference.com/w/cpp/named_req/MoveConstructible)
+    requirements.
+
+    @liveexample{The code below shows the move constructor explicitly called
+    via std::move.,basic_json__moveconstructor}
+
+    @since version 1.0.0
+    */
+    basic_json(basic_json&& other) noexcept
+        : m_type(std::move(other.m_type)),
+          m_value(std::move(other.m_value))
+    {
+        // check that passed value is valid
+        other.assert_invariant();
+
+        // invalidate payload
+        other.m_type = value_t::null;
+        other.m_value = {};
+
+        assert_invariant();
+    }
+
+    /*!
+    @brief copy assignment
+
+    Copy assignment operator. Copies a JSON value via the "copy and swap"
+    strategy: It is expressed in terms of the copy constructor, destructor,
+    and the `swap()` member function.
+
+    @param[in] other  value to copy from
+
+    @complexity Linear.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is linear.
+
+    @liveexample{The code below shows and example for the copy assignment. It
+    creates a copy of value `a` which is then swapped with `b`. Finally\, the
+    copy of `a` (which is the null value after the swap) is
+    destroyed.,basic_json__copyassignment}
+
+    @since version 1.0.0
+    */
+    basic_json& operator=(basic_json other) noexcept (
+        std::is_nothrow_move_constructible<value_t>::value and
+        std::is_nothrow_move_assignable<value_t>::value and
+        std::is_nothrow_move_constructible<json_value>::value and
+        std::is_nothrow_move_assignable<json_value>::value
+    )
+    {
+        // check that passed value is valid
+        other.assert_invariant();
+
+        using std::swap;
+        swap(m_type, other.m_type);
+        swap(m_value, other.m_value);
+
+        assert_invariant();
+        return *this;
+    }
+
+    /*!
+    @brief destructor
+
+    Destroys the JSON value and frees all allocated memory.
+
+    @complexity Linear.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is linear.
+    - All stored elements are destroyed and all memory is freed.
+
+    @since version 1.0.0
+    */
+    ~basic_json() noexcept
+    {
+        assert_invariant();
+        m_value.destroy(m_type);
+    }
+
+    /// @}
+
+  public:
+    ///////////////////////
+    // object inspection //
+    ///////////////////////
+
+    /// @name object inspection
+    /// Functions to inspect the type of a JSON value.
+    /// @{
+
+    /*!
+    @brief serialization
+
+    Serialization function for JSON values. The function tries to mimic
+    Python's `json.dumps()` function, and currently supports its @a indent
+    and @a ensure_ascii parameters.
+
+    @param[in] indent If indent is nonnegative, then array elements and object
+    members will be pretty-printed with that indent level. An indent level of
+    `0` will only insert newlines. `-1` (the default) selects the most compact
+    representation.
+    @param[in] indent_char The character to use for indentation if @a indent is
+    greater than `0`. The default is ` ` (space).
+    @param[in] ensure_ascii If @a ensure_ascii is true, all non-ASCII characters
+    in the output are escaped with `\uXXXX` sequences, and the result consists
+    of ASCII characters only.
+    @param[in] error_handler  how to react on decoding errors; there are three
+    possible values: `strict` (throws and exception in case a decoding error
+    occurs; default), `replace` (replace invalid UTF-8 sequences with U+FFFD),
+    and `ignore` (ignore invalid UTF-8 sequences during serialization).
+
+    @return string containing the serialization of the JSON value
+
+    @throw type_error.316 if a string stored inside the JSON value is not
+                          UTF-8 encoded
+
+    @complexity Linear.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @liveexample{The following example shows the effect of different @a indent\,
+    @a indent_char\, and @a ensure_ascii parameters to the result of the
+    serialization.,dump}
+
+    @see https://docs.python.org/2/library/json.html#json.dump
+
+    @since version 1.0.0; indentation character @a indent_char, option
+           @a ensure_ascii and exceptions added in version 3.0.0; error
+           handlers added in version 3.4.0.
+    */
+    string_t dump(const int indent = -1,
+                  const char indent_char = ' ',
+                  const bool ensure_ascii = false,
+                  const error_handler_t error_handler = error_handler_t::strict) const
+    {
+        string_t result;
+        serializer s(detail::output_adapter<char, string_t>(result), indent_char, error_handler);
+
+        if (indent >= 0)
+        {
+            s.dump(*this, true, ensure_ascii, static_cast<unsigned int>(indent));
+        }
+        else
+        {
+            s.dump(*this, false, ensure_ascii, 0);
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief return the type of the JSON value (explicit)
+
+    Return the type of the JSON value as a value from the @ref value_t
+    enumeration.
+
+    @return the type of the JSON value
+            Value type                | return value
+            ------------------------- | -------------------------
+            null                      | value_t::null
+            boolean                   | value_t::boolean
+            string                    | value_t::string
+            number (integer)          | value_t::number_integer
+            number (unsigned integer) | value_t::number_unsigned
+            number (floating-point)   | value_t::number_float
+            object                    | value_t::object
+            array                     | value_t::array
+            discarded                 | value_t::discarded
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `type()` for all JSON
+    types.,type}
+
+    @sa @ref operator value_t() -- return the type of the JSON value (implicit)
+    @sa @ref type_name() -- return the type as string
+
+    @since version 1.0.0
+    */
+    constexpr value_t type() const noexcept
+    {
+        return m_type;
+    }
+
+    /*!
+    @brief return whether type is primitive
+
+    This function returns true if and only if the JSON type is primitive
+    (string, number, boolean, or null).
+
+    @return `true` if type is primitive (string, number, boolean, or null),
+    `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_primitive()` for all JSON
+    types.,is_primitive}
+
+    @sa @ref is_structured() -- returns whether JSON value is structured
+    @sa @ref is_null() -- returns whether JSON value is `null`
+    @sa @ref is_string() -- returns whether JSON value is a string
+    @sa @ref is_boolean() -- returns whether JSON value is a boolean
+    @sa @ref is_number() -- returns whether JSON value is a number
+
+    @since version 1.0.0
+    */
+    constexpr bool is_primitive() const noexcept
+    {
+        return is_null() or is_string() or is_boolean() or is_number();
+    }
+
+    /*!
+    @brief return whether type is structured
+
+    This function returns true if and only if the JSON type is structured
+    (array or object).
+
+    @return `true` if type is structured (array or object), `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_structured()` for all JSON
+    types.,is_structured}
+
+    @sa @ref is_primitive() -- returns whether value is primitive
+    @sa @ref is_array() -- returns whether value is an array
+    @sa @ref is_object() -- returns whether value is an object
+
+    @since version 1.0.0
+    */
+    constexpr bool is_structured() const noexcept
+    {
+        return is_array() or is_object();
+    }
+
+    /*!
+    @brief return whether value is null
+
+    This function returns true if and only if the JSON value is null.
+
+    @return `true` if type is null, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_null()` for all JSON
+    types.,is_null}
+
+    @since version 1.0.0
+    */
+    constexpr bool is_null() const noexcept
+    {
+        return (m_type == value_t::null);
+    }
+
+    /*!
+    @brief return whether value is a boolean
+
+    This function returns true if and only if the JSON value is a boolean.
+
+    @return `true` if type is boolean, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_boolean()` for all JSON
+    types.,is_boolean}
+
+    @since version 1.0.0
+    */
+    constexpr bool is_boolean() const noexcept
+    {
+        return (m_type == value_t::boolean);
+    }
+
+    /*!
+    @brief return whether value is a number
+
+    This function returns true if and only if the JSON value is a number. This
+    includes both integer (signed and unsigned) and floating-point values.
+
+    @return `true` if type is number (regardless whether integer, unsigned
+    integer or floating-type), `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_number()` for all JSON
+    types.,is_number}
+
+    @sa @ref is_number_integer() -- check if value is an integer or unsigned
+    integer number
+    @sa @ref is_number_unsigned() -- check if value is an unsigned integer
+    number
+    @sa @ref is_number_float() -- check if value is a floating-point number
+
+    @since version 1.0.0
+    */
+    constexpr bool is_number() const noexcept
+    {
+        return is_number_integer() or is_number_float();
+    }
+
+    /*!
+    @brief return whether value is an integer number
+
+    This function returns true if and only if the JSON value is a signed or
+    unsigned integer number. This excludes floating-point values.
+
+    @return `true` if type is an integer or unsigned integer number, `false`
+    otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_number_integer()` for all
+    JSON types.,is_number_integer}
+
+    @sa @ref is_number() -- check if value is a number
+    @sa @ref is_number_unsigned() -- check if value is an unsigned integer
+    number
+    @sa @ref is_number_float() -- check if value is a floating-point number
+
+    @since version 1.0.0
+    */
+    constexpr bool is_number_integer() const noexcept
+    {
+        return (m_type == value_t::number_integer or m_type == value_t::number_unsigned);
+    }
+
+    /*!
+    @brief return whether value is an unsigned integer number
+
+    This function returns true if and only if the JSON value is an unsigned
+    integer number. This excludes floating-point and signed integer values.
+
+    @return `true` if type is an unsigned integer number, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_number_unsigned()` for all
+    JSON types.,is_number_unsigned}
+
+    @sa @ref is_number() -- check if value is a number
+    @sa @ref is_number_integer() -- check if value is an integer or unsigned
+    integer number
+    @sa @ref is_number_float() -- check if value is a floating-point number
+
+    @since version 2.0.0
+    */
+    constexpr bool is_number_unsigned() const noexcept
+    {
+        return (m_type == value_t::number_unsigned);
+    }
+
+    /*!
+    @brief return whether value is a floating-point number
+
+    This function returns true if and only if the JSON value is a
+    floating-point number. This excludes signed and unsigned integer values.
+
+    @return `true` if type is a floating-point number, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_number_float()` for all
+    JSON types.,is_number_float}
+
+    @sa @ref is_number() -- check if value is number
+    @sa @ref is_number_integer() -- check if value is an integer number
+    @sa @ref is_number_unsigned() -- check if value is an unsigned integer
+    number
+
+    @since version 1.0.0
+    */
+    constexpr bool is_number_float() const noexcept
+    {
+        return (m_type == value_t::number_float);
+    }
+
+    /*!
+    @brief return whether value is an object
+
+    This function returns true if and only if the JSON value is an object.
+
+    @return `true` if type is object, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_object()` for all JSON
+    types.,is_object}
+
+    @since version 1.0.0
+    */
+    constexpr bool is_object() const noexcept
+    {
+        return (m_type == value_t::object);
+    }
+
+    /*!
+    @brief return whether value is an array
+
+    This function returns true if and only if the JSON value is an array.
+
+    @return `true` if type is array, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_array()` for all JSON
+    types.,is_array}
+
+    @since version 1.0.0
+    */
+    constexpr bool is_array() const noexcept
+    {
+        return (m_type == value_t::array);
+    }
+
+    /*!
+    @brief return whether value is a string
+
+    This function returns true if and only if the JSON value is a string.
+
+    @return `true` if type is string, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_string()` for all JSON
+    types.,is_string}
+
+    @since version 1.0.0
+    */
+    constexpr bool is_string() const noexcept
+    {
+        return (m_type == value_t::string);
+    }
+
+    /*!
+    @brief return whether value is discarded
+
+    This function returns true if and only if the JSON value was discarded
+    during parsing with a callback function (see @ref parser_callback_t).
+
+    @note This function will always be `false` for JSON values after parsing.
+    That is, discarded values can only occur during parsing, but will be
+    removed when inside a structured value or replaced by null in other cases.
+
+    @return `true` if type is discarded, `false` otherwise.
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies `is_discarded()` for all JSON
+    types.,is_discarded}
+
+    @since version 1.0.0
+    */
+    constexpr bool is_discarded() const noexcept
+    {
+        return (m_type == value_t::discarded);
+    }
+
+    /*!
+    @brief return the type of the JSON value (implicit)
+
+    Implicitly return the type of the JSON value as a value from the @ref
+    value_t enumeration.
+
+    @return the type of the JSON value
+
+    @complexity Constant.
+
+    @exceptionsafety No-throw guarantee: this member function never throws
+    exceptions.
+
+    @liveexample{The following code exemplifies the @ref value_t operator for
+    all JSON types.,operator__value_t}
+
+    @sa @ref type() -- return the type of the JSON value (explicit)
+    @sa @ref type_name() -- return the type as string
+
+    @since version 1.0.0
+    */
+    constexpr operator value_t() const noexcept
+    {
+        return m_type;
+    }
+
+    /// @}
+
+  private:
+    //////////////////
+    // value access //
+    //////////////////
+
+    /// get a boolean (explicit)
+    boolean_t get_impl(boolean_t* /*unused*/) const
+    {
+        if (JSON_LIKELY(is_boolean()))
+        {
+            return m_value.boolean;
+        }
+
+        JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(type_name())));
+    }
+
+    /// get a pointer to the value (object)
+    object_t* get_impl_ptr(object_t* /*unused*/) noexcept
+    {
+        return is_object() ? m_value.object : nullptr;
+    }
+
+    /// get a pointer to the value (object)
+    constexpr const object_t* get_impl_ptr(const object_t* /*unused*/) const noexcept
+    {
+        return is_object() ? m_value.object : nullptr;
+    }
+
+    /// get a pointer to the value (array)
+    array_t* get_impl_ptr(array_t* /*unused*/) noexcept
+    {
+        return is_array() ? m_value.array : nullptr;
+    }
+
+    /// get a pointer to the value (array)
+    constexpr const array_t* get_impl_ptr(const array_t* /*unused*/) const noexcept
+    {
+        return is_array() ? m_value.array : nullptr;
+    }
+
+    /// get a pointer to the value (string)
+    string_t* get_impl_ptr(string_t* /*unused*/) noexcept
+    {
+        return is_string() ? m_value.string : nullptr;
+    }
+
+    /// get a pointer to the value (string)
+    constexpr const string_t* get_impl_ptr(const string_t* /*unused*/) const noexcept
+    {
+        return is_string() ? m_value.string : nullptr;
+    }
+
+    /// get a pointer to the value (boolean)
+    boolean_t* get_impl_ptr(boolean_t* /*unused*/) noexcept
+    {
+        return is_boolean() ? &m_value.boolean : nullptr;
+    }
+
+    /// get a pointer to the value (boolean)
+    constexpr const boolean_t* get_impl_ptr(const boolean_t* /*unused*/) const noexcept
+    {
+        return is_boolean() ? &m_value.boolean : nullptr;
+    }
+
+    /// get a pointer to the value (integer number)
+    number_integer_t* get_impl_ptr(number_integer_t* /*unused*/) noexcept
+    {
+        return is_number_integer() ? &m_value.number_integer : nullptr;
+    }
+
+    /// get a pointer to the value (integer number)
+    constexpr const number_integer_t* get_impl_ptr(const number_integer_t* /*unused*/) const noexcept
+    {
+        return is_number_integer() ? &m_value.number_integer : nullptr;
+    }
+
+    /// get a pointer to the value (unsigned number)
+    number_unsigned_t* get_impl_ptr(number_unsigned_t* /*unused*/) noexcept
+    {
+        return is_number_unsigned() ? &m_value.number_unsigned : nullptr;
+    }
+
+    /// get a pointer to the value (unsigned number)
+    constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t* /*unused*/) const noexcept
+    {
+        return is_number_unsigned() ? &m_value.number_unsigned : nullptr;
+    }
+
+    /// get a pointer to the value (floating-point number)
+    number_float_t* get_impl_ptr(number_float_t* /*unused*/) noexcept
+    {
+        return is_number_float() ? &m_value.number_float : nullptr;
+    }
+
+    /// get a pointer to the value (floating-point number)
+    constexpr const number_float_t* get_impl_ptr(const number_float_t* /*unused*/) const noexcept
+    {
+        return is_number_float() ? &m_value.number_float : nullptr;
+    }
+
+    /*!
+    @brief helper function to implement get_ref()
+
+    This function helps to implement get_ref() without code duplication for
+    const and non-const overloads
+
+    @tparam ThisType will be deduced as `basic_json` or `const basic_json`
+
+    @throw type_error.303 if ReferenceType does not match underlying value
+    type of the current JSON
+    */
+    template<typename ReferenceType, typename ThisType>
+    static ReferenceType get_ref_impl(ThisType& obj)
+    {
+        // delegate the call to get_ptr<>()
+        auto ptr = obj.template get_ptr<typename std::add_pointer<ReferenceType>::type>();
+
+        if (JSON_LIKELY(ptr != nullptr))
+        {
+            return *ptr;
+        }
+
+        JSON_THROW(type_error::create(303, "incompatible ReferenceType for get_ref, actual type is " + std::string(obj.type_name())));
+    }
+
+  public:
+    /// @name value access
+    /// Direct access to the stored value of a JSON value.
+    /// @{
+
+    /*!
+    @brief get special-case overload
+
+    This overloads avoids a lot of template boilerplate, it can be seen as the
+    identity method
+
+    @tparam BasicJsonType == @ref basic_json
+
+    @return a copy of *this
+
+    @complexity Constant.
+
+    @since version 2.1.0
+    */
+    template<typename BasicJsonType, detail::enable_if_t<
+                 std::is_same<typename std::remove_const<BasicJsonType>::type, basic_json_t>::value,
+                 int> = 0>
+    basic_json get() const
+    {
+        return *this;
+    }
+
+    /*!
+    @brief get special-case overload
+
+    This overloads converts the current @ref basic_json in a different
+    @ref basic_json type
+
+    @tparam BasicJsonType == @ref basic_json
+
+    @return a copy of *this, converted into @tparam BasicJsonType
+
+    @complexity Depending on the implementation of the called `from_json()`
+                method.
+
+    @since version 3.2.0
+    */
+    template<typename BasicJsonType, detail::enable_if_t<
+                 not std::is_same<BasicJsonType, basic_json>::value and
+                 detail::is_basic_json<BasicJsonType>::value, int> = 0>
+    BasicJsonType get() const
+    {
+        return *this;
+    }
+
+    /*!
+    @brief get a value (explicit)
+
+    Explicit type conversion between the JSON value and a compatible value
+    which is [CopyConstructible](https://en.cppreference.com/w/cpp/named_req/CopyConstructible)
+    and [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible).
+    The value is converted by calling the @ref json_serializer<ValueType>
+    `from_json()` method.
+
+    The function is equivalent to executing
+    @code {.cpp}
+    ValueType ret;
+    JSONSerializer<ValueType>::from_json(*this, ret);
+    return ret;
+    @endcode
+
+    This overloads is chosen if:
+    - @a ValueType is not @ref basic_json,
+    - @ref json_serializer<ValueType> has a `from_json()` method of the form
+      `void from_json(const basic_json&, ValueType&)`, and
+    - @ref json_serializer<ValueType> does not have a `from_json()` method of
+      the form `ValueType from_json(const basic_json&)`
+
+    @tparam ValueTypeCV the provided value type
+    @tparam ValueType the returned value type
+
+    @return copy of the JSON value, converted to @a ValueType
+
+    @throw what @ref json_serializer<ValueType> `from_json()` method throws
+
+    @liveexample{The example below shows several conversions from JSON values
+    to other types. There a few things to note: (1) Floating-point numbers can
+    be converted to integers\, (2) A JSON array can be converted to a standard
+    `std::vector<short>`\, (3) A JSON object can be converted to C++
+    associative containers such as `std::unordered_map<std::string\,
+    json>`.,get__ValueType_const}
+
+    @since version 2.1.0
+    */
+    template<typename ValueTypeCV, typename ValueType = detail::uncvref_t<ValueTypeCV>,
+             detail::enable_if_t <
+                 not detail::is_basic_json<ValueType>::value and
+                 detail::has_from_json<basic_json_t, ValueType>::value and
+                 not detail::has_non_default_from_json<basic_json_t, ValueType>::value,
+                 int> = 0>
+    ValueType get() const noexcept(noexcept(
+                                       JSONSerializer<ValueType>::from_json(std::declval<const basic_json_t&>(), std::declval<ValueType&>())))
+    {
+        // we cannot static_assert on ValueTypeCV being non-const, because
+        // there is support for get<const basic_json_t>(), which is why we
+        // still need the uncvref
+        static_assert(not std::is_reference<ValueTypeCV>::value,
+                      "get() cannot be used with reference types, you might want to use get_ref()");
+        static_assert(std::is_default_constructible<ValueType>::value,
+                      "types must be DefaultConstructible when used with get()");
+
+        ValueType ret;
+        JSONSerializer<ValueType>::from_json(*this, ret);
+        return ret;
+    }
+
+    /*!
+    @brief get a value (explicit); special case
+
+    Explicit type conversion between the JSON value and a compatible value
+    which is **not** [CopyConstructible](https://en.cppreference.com/w/cpp/named_req/CopyConstructible)
+    and **not** [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible).
+    The value is converted by calling the @ref json_serializer<ValueType>
+    `from_json()` method.
+
+    The function is equivalent to executing
+    @code {.cpp}
+    return JSONSerializer<ValueTypeCV>::from_json(*this);
+    @endcode
+
+    This overloads is chosen if:
+    - @a ValueType is not @ref basic_json and
+    - @ref json_serializer<ValueType> has a `from_json()` method of the form
+      `ValueType from_json(const basic_json&)`
+
+    @note If @ref json_serializer<ValueType> has both overloads of
+    `from_json()`, this one is chosen.
+
+    @tparam ValueTypeCV the provided value type
+    @tparam ValueType the returned value type
+
+    @return copy of the JSON value, converted to @a ValueType
+
+    @throw what @ref json_serializer<ValueType> `from_json()` method throws
+
+    @since version 2.1.0
+    */
+    template<typename ValueTypeCV, typename ValueType = detail::uncvref_t<ValueTypeCV>,
+             detail::enable_if_t<not std::is_same<basic_json_t, ValueType>::value and
+                                 detail::has_non_default_from_json<basic_json_t, ValueType>::value,
+                                 int> = 0>
+    ValueType get() const noexcept(noexcept(
+                                       JSONSerializer<ValueTypeCV>::from_json(std::declval<const basic_json_t&>())))
+    {
+        static_assert(not std::is_reference<ValueTypeCV>::value,
+                      "get() cannot be used with reference types, you might want to use get_ref()");
+        return JSONSerializer<ValueTypeCV>::from_json(*this);
+    }
+
+    /*!
+    @brief get a value (explicit)
+
+    Explicit type conversion between the JSON value and a compatible value.
+    The value is filled into the input parameter by calling the @ref json_serializer<ValueType>
+    `from_json()` method.
+
+    The function is equivalent to executing
+    @code {.cpp}
+    ValueType v;
+    JSONSerializer<ValueType>::from_json(*this, v);
+    @endcode
+
+    This overloads is chosen if:
+    - @a ValueType is not @ref basic_json,
+    - @ref json_serializer<ValueType> has a `from_json()` method of the form
+      `void from_json(const basic_json&, ValueType&)`, and
+
+    @tparam ValueType the input parameter type.
+
+    @return the input parameter, allowing chaining calls.
+
+    @throw what @ref json_serializer<ValueType> `from_json()` method throws
+
+    @liveexample{The example below shows several conversions from JSON values
+    to other types. There a few things to note: (1) Floating-point numbers can
+    be converted to integers\, (2) A JSON array can be converted to a standard
+    `std::vector<short>`\, (3) A JSON object can be converted to C++
+    associative containers such as `std::unordered_map<std::string\,
+    json>`.,get_to}
+
+    @since version 3.3.0
+    */
+    template<typename ValueType,
+             detail::enable_if_t <
+                 not detail::is_basic_json<ValueType>::value and
+                 detail::has_from_json<basic_json_t, ValueType>::value,
+                 int> = 0>
+    ValueType & get_to(ValueType& v) const noexcept(noexcept(
+                JSONSerializer<ValueType>::from_json(std::declval<const basic_json_t&>(), v)))
+    {
+        JSONSerializer<ValueType>::from_json(*this, v);
+        return v;
+    }
+
+
+    /*!
+    @brief get a pointer value (implicit)
+
+    Implicit pointer access to the internally stored JSON value. No copies are
+    made.
+
+    @warning Writing data to the pointee of the result yields an undefined
+    state.
+
+    @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref
+    object_t, @ref string_t, @ref boolean_t, @ref number_integer_t,
+    @ref number_unsigned_t, or @ref number_float_t. Enforced by a static
+    assertion.
+
+    @return pointer to the internally stored JSON value if the requested
+    pointer type @a PointerType fits to the JSON value; `nullptr` otherwise
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how pointers to internal values of a
+    JSON value can be requested. Note that no type conversions are made and a
+    `nullptr` is returned if the value and the requested pointer type does not
+    match.,get_ptr}
+
+    @since version 1.0.0
+    */
+    template<typename PointerType, typename std::enable_if<
+                 std::is_pointer<PointerType>::value, int>::type = 0>
+    auto get_ptr() noexcept -> decltype(std::declval<basic_json_t&>().get_impl_ptr(std::declval<PointerType>()))
+    {
+        // delegate the call to get_impl_ptr<>()
+        return get_impl_ptr(static_cast<PointerType>(nullptr));
+    }
+
+    /*!
+    @brief get a pointer value (implicit)
+    @copydoc get_ptr()
+    */
+    template<typename PointerType, typename std::enable_if<
+                 std::is_pointer<PointerType>::value and
+                 std::is_const<typename std::remove_pointer<PointerType>::type>::value, int>::type = 0>
+    constexpr auto get_ptr() const noexcept -> decltype(std::declval<const basic_json_t&>().get_impl_ptr(std::declval<PointerType>()))
+    {
+        // delegate the call to get_impl_ptr<>() const
+        return get_impl_ptr(static_cast<PointerType>(nullptr));
+    }
+
+    /*!
+    @brief get a pointer value (explicit)
+
+    Explicit pointer access to the internally stored JSON value. No copies are
+    made.
+
+    @warning The pointer becomes invalid if the underlying JSON object
+    changes.
+
+    @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref
+    object_t, @ref string_t, @ref boolean_t, @ref number_integer_t,
+    @ref number_unsigned_t, or @ref number_float_t.
+
+    @return pointer to the internally stored JSON value if the requested
+    pointer type @a PointerType fits to the JSON value; `nullptr` otherwise
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how pointers to internal values of a
+    JSON value can be requested. Note that no type conversions are made and a
+    `nullptr` is returned if the value and the requested pointer type does not
+    match.,get__PointerType}
+
+    @sa @ref get_ptr() for explicit pointer-member access
+
+    @since version 1.0.0
+    */
+    template<typename PointerType, typename std::enable_if<
+                 std::is_pointer<PointerType>::value, int>::type = 0>
+    auto get() noexcept -> decltype(std::declval<basic_json_t&>().template get_ptr<PointerType>())
+    {
+        // delegate the call to get_ptr
+        return get_ptr<PointerType>();
+    }
+
+    /*!
+    @brief get a pointer value (explicit)
+    @copydoc get()
+    */
+    template<typename PointerType, typename std::enable_if<
+                 std::is_pointer<PointerType>::value, int>::type = 0>
+    constexpr auto get() const noexcept -> decltype(std::declval<const basic_json_t&>().template get_ptr<PointerType>())
+    {
+        // delegate the call to get_ptr
+        return get_ptr<PointerType>();
+    }
+
+    /*!
+    @brief get a reference value (implicit)
+
+    Implicit reference access to the internally stored JSON value. No copies
+    are made.
+
+    @warning Writing data to the referee of the result yields an undefined
+    state.
+
+    @tparam ReferenceType reference type; must be a reference to @ref array_t,
+    @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, or
+    @ref number_float_t. Enforced by static assertion.
+
+    @return reference to the internally stored JSON value if the requested
+    reference type @a ReferenceType fits to the JSON value; throws
+    type_error.303 otherwise
+
+    @throw type_error.303 in case passed type @a ReferenceType is incompatible
+    with the stored JSON value; see example below
+
+    @complexity Constant.
+
+    @liveexample{The example shows several calls to `get_ref()`.,get_ref}
+
+    @since version 1.1.0
+    */
+    template<typename ReferenceType, typename std::enable_if<
+                 std::is_reference<ReferenceType>::value, int>::type = 0>
+    ReferenceType get_ref()
+    {
+        // delegate call to get_ref_impl
+        return get_ref_impl<ReferenceType>(*this);
+    }
+
+    /*!
+    @brief get a reference value (implicit)
+    @copydoc get_ref()
+    */
+    template<typename ReferenceType, typename std::enable_if<
+                 std::is_reference<ReferenceType>::value and
+                 std::is_const<typename std::remove_reference<ReferenceType>::type>::value, int>::type = 0>
+    ReferenceType get_ref() const
+    {
+        // delegate call to get_ref_impl
+        return get_ref_impl<ReferenceType>(*this);
+    }
+
+    /*!
+    @brief get a value (implicit)
+
+    Implicit type conversion between the JSON value and a compatible value.
+    The call is realized by calling @ref get() const.
+
+    @tparam ValueType non-pointer type compatible to the JSON value, for
+    instance `int` for JSON integer numbers, `bool` for JSON booleans, or
+    `std::vector` types for JSON arrays. The character type of @ref string_t
+    as well as an initializer list of this type is excluded to avoid
+    ambiguities as these types implicitly convert to `std::string`.
+
+    @return copy of the JSON value, converted to type @a ValueType
+
+    @throw type_error.302 in case passed type @a ValueType is incompatible
+    to the JSON value type (e.g., the JSON value is of type boolean, but a
+    string is requested); see example below
+
+    @complexity Linear in the size of the JSON value.
+
+    @liveexample{The example below shows several conversions from JSON values
+    to other types. There a few things to note: (1) Floating-point numbers can
+    be converted to integers\, (2) A JSON array can be converted to a standard
+    `std::vector<short>`\, (3) A JSON object can be converted to C++
+    associative containers such as `std::unordered_map<std::string\,
+    json>`.,operator__ValueType}
+
+    @since version 1.0.0
+    */
+    template < typename ValueType, typename std::enable_if <
+                   not std::is_pointer<ValueType>::value and
+                   not std::is_same<ValueType, detail::json_ref<basic_json>>::value and
+                   not std::is_same<ValueType, typename string_t::value_type>::value and
+                   not detail::is_basic_json<ValueType>::value
+
+#ifndef _MSC_VER  // fix for issue #167 operator<< ambiguity under VS2015
+                   and not std::is_same<ValueType, std::initializer_list<typename string_t::value_type>>::value
+#if defined(JSON_HAS_CPP_17) && defined(_MSC_VER) and _MSC_VER <= 1914
+                   and not std::is_same<ValueType, typename std::string_view>::value
+#endif
+#endif
+                   and detail::is_detected<detail::get_template_function, const basic_json_t&, ValueType>::value
+                   , int >::type = 0 >
+    operator ValueType() const
+    {
+        // delegate the call to get<>() const
+        return get<ValueType>();
+    }
+
+    /// @}
+
+
+    ////////////////////
+    // element access //
+    ////////////////////
+
+    /// @name element access
+    /// Access to the JSON value.
+    /// @{
+
+    /*!
+    @brief access specified array element with bounds checking
+
+    Returns a reference to the element at specified location @a idx, with
+    bounds checking.
+
+    @param[in] idx  index of the element to access
+
+    @return reference to the element at index @a idx
+
+    @throw type_error.304 if the JSON value is not an array; in this case,
+    calling `at` with an index makes no sense. See example below.
+    @throw out_of_range.401 if the index @a idx is out of range of the array;
+    that is, `idx >= size()`. See example below.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Constant.
+
+    @since version 1.0.0
+
+    @liveexample{The example below shows how array elements can be read and
+    written using `at()`. It also demonstrates the different exceptions that
+    can be thrown.,at__size_type}
+    */
+    reference at(size_type idx)
+    {
+        // at only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            JSON_TRY
+            {
+                return m_value.array->at(idx);
+            }
+            JSON_CATCH (std::out_of_range&)
+            {
+                // create better exception explanation
+                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range"));
+            }
+        }
+        else
+        {
+            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name())));
+        }
+    }
+
+    /*!
+    @brief access specified array element with bounds checking
+
+    Returns a const reference to the element at specified location @a idx,
+    with bounds checking.
+
+    @param[in] idx  index of the element to access
+
+    @return const reference to the element at index @a idx
+
+    @throw type_error.304 if the JSON value is not an array; in this case,
+    calling `at` with an index makes no sense. See example below.
+    @throw out_of_range.401 if the index @a idx is out of range of the array;
+    that is, `idx >= size()`. See example below.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Constant.
+
+    @since version 1.0.0
+
+    @liveexample{The example below shows how array elements can be read using
+    `at()`. It also demonstrates the different exceptions that can be thrown.,
+    at__size_type_const}
+    */
+    const_reference at(size_type idx) const
+    {
+        // at only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            JSON_TRY
+            {
+                return m_value.array->at(idx);
+            }
+            JSON_CATCH (std::out_of_range&)
+            {
+                // create better exception explanation
+                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range"));
+            }
+        }
+        else
+        {
+            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name())));
+        }
+    }
+
+    /*!
+    @brief access specified object element with bounds checking
+
+    Returns a reference to the element at with specified key @a key, with
+    bounds checking.
+
+    @param[in] key  key of the element to access
+
+    @return reference to the element at key @a key
+
+    @throw type_error.304 if the JSON value is not an object; in this case,
+    calling `at` with a key makes no sense. See example below.
+    @throw out_of_range.403 if the key @a key is is not stored in the object;
+    that is, `find(key) == end()`. See example below.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Logarithmic in the size of the container.
+
+    @sa @ref operator[](const typename object_t::key_type&) for unchecked
+    access by reference
+    @sa @ref value() for access by value with a default value
+
+    @since version 1.0.0
+
+    @liveexample{The example below shows how object elements can be read and
+    written using `at()`. It also demonstrates the different exceptions that
+    can be thrown.,at__object_t_key_type}
+    */
+    reference at(const typename object_t::key_type& key)
+    {
+        // at only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            JSON_TRY
+            {
+                return m_value.object->at(key);
+            }
+            JSON_CATCH (std::out_of_range&)
+            {
+                // create better exception explanation
+                JSON_THROW(out_of_range::create(403, "key '" + key + "' not found"));
+            }
+        }
+        else
+        {
+            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name())));
+        }
+    }
+
+    /*!
+    @brief access specified object element with bounds checking
+
+    Returns a const reference to the element at with specified key @a key,
+    with bounds checking.
+
+    @param[in] key  key of the element to access
+
+    @return const reference to the element at key @a key
+
+    @throw type_error.304 if the JSON value is not an object; in this case,
+    calling `at` with a key makes no sense. See example below.
+    @throw out_of_range.403 if the key @a key is is not stored in the object;
+    that is, `find(key) == end()`. See example below.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Logarithmic in the size of the container.
+
+    @sa @ref operator[](const typename object_t::key_type&) for unchecked
+    access by reference
+    @sa @ref value() for access by value with a default value
+
+    @since version 1.0.0
+
+    @liveexample{The example below shows how object elements can be read using
+    `at()`. It also demonstrates the different exceptions that can be thrown.,
+    at__object_t_key_type_const}
+    */
+    const_reference at(const typename object_t::key_type& key) const
+    {
+        // at only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            JSON_TRY
+            {
+                return m_value.object->at(key);
+            }
+            JSON_CATCH (std::out_of_range&)
+            {
+                // create better exception explanation
+                JSON_THROW(out_of_range::create(403, "key '" + key + "' not found"));
+            }
+        }
+        else
+        {
+            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name())));
+        }
+    }
+
+    /*!
+    @brief access specified array element
+
+    Returns a reference to the element at specified location @a idx.
+
+    @note If @a idx is beyond the range of the array (i.e., `idx >= size()`),
+    then the array is silently filled up with `null` values to make `idx` a
+    valid reference to the last stored element.
+
+    @param[in] idx  index of the element to access
+
+    @return reference to the element at index @a idx
+
+    @throw type_error.305 if the JSON value is not an array or null; in that
+    cases, using the [] operator with an index makes no sense.
+
+    @complexity Constant if @a idx is in the range of the array. Otherwise
+    linear in `idx - size()`.
+
+    @liveexample{The example below shows how array elements can be read and
+    written using `[]` operator. Note the addition of `null`
+    values.,operatorarray__size_type}
+
+    @since version 1.0.0
+    */
+    reference operator[](size_type idx)
+    {
+        // implicitly convert null value to an empty array
+        if (is_null())
+        {
+            m_type = value_t::array;
+            m_value.array = create<array_t>();
+            assert_invariant();
+        }
+
+        // operator[] only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            // fill up array with null values if given idx is outside range
+            if (idx >= m_value.array->size())
+            {
+                m_value.array->insert(m_value.array->end(),
+                                      idx - m_value.array->size() + 1,
+                                      basic_json());
+            }
+
+            return m_value.array->operator[](idx);
+        }
+
+        JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief access specified array element
+
+    Returns a const reference to the element at specified location @a idx.
+
+    @param[in] idx  index of the element to access
+
+    @return const reference to the element at index @a idx
+
+    @throw type_error.305 if the JSON value is not an array; in that case,
+    using the [] operator with an index makes no sense.
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how array elements can be read using
+    the `[]` operator.,operatorarray__size_type_const}
+
+    @since version 1.0.0
+    */
+    const_reference operator[](size_type idx) const
+    {
+        // const operator[] only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            return m_value.array->operator[](idx);
+        }
+
+        JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief access specified object element
+
+    Returns a reference to the element at with specified key @a key.
+
+    @note If @a key is not found in the object, then it is silently added to
+    the object and filled with a `null` value to make `key` a valid reference.
+    In case the value was `null` before, it is converted to an object.
+
+    @param[in] key  key of the element to access
+
+    @return reference to the element at key @a key
+
+    @throw type_error.305 if the JSON value is not an object or null; in that
+    cases, using the [] operator with a key makes no sense.
+
+    @complexity Logarithmic in the size of the container.
+
+    @liveexample{The example below shows how object elements can be read and
+    written using the `[]` operator.,operatorarray__key_type}
+
+    @sa @ref at(const typename object_t::key_type&) for access by reference
+    with range checking
+    @sa @ref value() for access by value with a default value
+
+    @since version 1.0.0
+    */
+    reference operator[](const typename object_t::key_type& key)
+    {
+        // implicitly convert null value to an empty object
+        if (is_null())
+        {
+            m_type = value_t::object;
+            m_value.object = create<object_t>();
+            assert_invariant();
+        }
+
+        // operator[] only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            return m_value.object->operator[](key);
+        }
+
+        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief read-only access specified object element
+
+    Returns a const reference to the element at with specified key @a key. No
+    bounds checking is performed.
+
+    @warning If the element with key @a key does not exist, the behavior is
+    undefined.
+
+    @param[in] key  key of the element to access
+
+    @return const reference to the element at key @a key
+
+    @pre The element with key @a key must exist. **This precondition is
+         enforced with an assertion.**
+
+    @throw type_error.305 if the JSON value is not an object; in that case,
+    using the [] operator with a key makes no sense.
+
+    @complexity Logarithmic in the size of the container.
+
+    @liveexample{The example below shows how object elements can be read using
+    the `[]` operator.,operatorarray__key_type_const}
+
+    @sa @ref at(const typename object_t::key_type&) for access by reference
+    with range checking
+    @sa @ref value() for access by value with a default value
+
+    @since version 1.0.0
+    */
+    const_reference operator[](const typename object_t::key_type& key) const
+    {
+        // const operator[] only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            assert(m_value.object->find(key) != m_value.object->end());
+            return m_value.object->find(key)->second;
+        }
+
+        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief access specified object element
+
+    Returns a reference to the element at with specified key @a key.
+
+    @note If @a key is not found in the object, then it is silently added to
+    the object and filled with a `null` value to make `key` a valid reference.
+    In case the value was `null` before, it is converted to an object.
+
+    @param[in] key  key of the element to access
+
+    @return reference to the element at key @a key
+
+    @throw type_error.305 if the JSON value is not an object or null; in that
+    cases, using the [] operator with a key makes no sense.
+
+    @complexity Logarithmic in the size of the container.
+
+    @liveexample{The example below shows how object elements can be read and
+    written using the `[]` operator.,operatorarray__key_type}
+
+    @sa @ref at(const typename object_t::key_type&) for access by reference
+    with range checking
+    @sa @ref value() for access by value with a default value
+
+    @since version 1.1.0
+    */
+    template<typename T>
+    reference operator[](T* key)
+    {
+        // implicitly convert null to object
+        if (is_null())
+        {
+            m_type = value_t::object;
+            m_value = value_t::object;
+            assert_invariant();
+        }
+
+        // at only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            return m_value.object->operator[](key);
+        }
+
+        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief read-only access specified object element
+
+    Returns a const reference to the element at with specified key @a key. No
+    bounds checking is performed.
+
+    @warning If the element with key @a key does not exist, the behavior is
+    undefined.
+
+    @param[in] key  key of the element to access
+
+    @return const reference to the element at key @a key
+
+    @pre The element with key @a key must exist. **This precondition is
+         enforced with an assertion.**
+
+    @throw type_error.305 if the JSON value is not an object; in that case,
+    using the [] operator with a key makes no sense.
+
+    @complexity Logarithmic in the size of the container.
+
+    @liveexample{The example below shows how object elements can be read using
+    the `[]` operator.,operatorarray__key_type_const}
+
+    @sa @ref at(const typename object_t::key_type&) for access by reference
+    with range checking
+    @sa @ref value() for access by value with a default value
+
+    @since version 1.1.0
+    */
+    template<typename T>
+    const_reference operator[](T* key) const
+    {
+        // at only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            assert(m_value.object->find(key) != m_value.object->end());
+            return m_value.object->find(key)->second;
+        }
+
+        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief access specified object element with default value
+
+    Returns either a copy of an object's element at the specified key @a key
+    or a given default value if no element with key @a key exists.
+
+    The function is basically equivalent to executing
+    @code {.cpp}
+    try {
+        return at(key);
+    } catch(out_of_range) {
+        return default_value;
+    }
+    @endcode
+
+    @note Unlike @ref at(const typename object_t::key_type&), this function
+    does not throw if the given key @a key was not found.
+
+    @note Unlike @ref operator[](const typename object_t::key_type& key), this
+    function does not implicitly add an element to the position defined by @a
+    key. This function is furthermore also applicable to const objects.
+
+    @param[in] key  key of the element to access
+    @param[in] default_value  the value to return if @a key is not found
+
+    @tparam ValueType type compatible to JSON values, for instance `int` for
+    JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
+    JSON arrays. Note the type of the expected value at @a key and the default
+    value @a default_value must be compatible.
+
+    @return copy of the element at key @a key or @a default_value if @a key
+    is not found
+
+    @throw type_error.306 if the JSON value is not an object; in that case,
+    using `value()` with a key makes no sense.
+
+    @complexity Logarithmic in the size of the container.
+
+    @liveexample{The example below shows how object elements can be queried
+    with a default value.,basic_json__value}
+
+    @sa @ref at(const typename object_t::key_type&) for access by reference
+    with range checking
+    @sa @ref operator[](const typename object_t::key_type&) for unchecked
+    access by reference
+
+    @since version 1.0.0
+    */
+    template<class ValueType, typename std::enable_if<
+                 std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0>
+    ValueType value(const typename object_t::key_type& key, const ValueType& default_value) const
+    {
+        // at only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            // if key is found, return value and given default value otherwise
+            const auto it = find(key);
+            if (it != end())
+            {
+                return *it;
+            }
+
+            return default_value;
+        }
+
+        JSON_THROW(type_error::create(306, "cannot use value() with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief overload for a default value of type const char*
+    @copydoc basic_json::value(const typename object_t::key_type&, const ValueType&) const
+    */
+    string_t value(const typename object_t::key_type& key, const char* default_value) const
+    {
+        return value(key, string_t(default_value));
+    }
+
+    /*!
+    @brief access specified object element via JSON Pointer with default value
+
+    Returns either a copy of an object's element at the specified key @a key
+    or a given default value if no element with key @a key exists.
+
+    The function is basically equivalent to executing
+    @code {.cpp}
+    try {
+        return at(ptr);
+    } catch(out_of_range) {
+        return default_value;
+    }
+    @endcode
+
+    @note Unlike @ref at(const json_pointer&), this function does not throw
+    if the given key @a key was not found.
+
+    @param[in] ptr  a JSON pointer to the element to access
+    @param[in] default_value  the value to return if @a ptr found no value
+
+    @tparam ValueType type compatible to JSON values, for instance `int` for
+    JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
+    JSON arrays. Note the type of the expected value at @a key and the default
+    value @a default_value must be compatible.
+
+    @return copy of the element at key @a key or @a default_value if @a key
+    is not found
+
+    @throw type_error.306 if the JSON value is not an object; in that case,
+    using `value()` with a key makes no sense.
+
+    @complexity Logarithmic in the size of the container.
+
+    @liveexample{The example below shows how object elements can be queried
+    with a default value.,basic_json__value_ptr}
+
+    @sa @ref operator[](const json_pointer&) for unchecked access by reference
+
+    @since version 2.0.2
+    */
+    template<class ValueType, typename std::enable_if<
+                 std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0>
+    ValueType value(const json_pointer& ptr, const ValueType& default_value) const
+    {
+        // at only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            // if pointer resolves a value, return it or use default value
+            JSON_TRY
+            {
+                return ptr.get_checked(this);
+            }
+            JSON_INTERNAL_CATCH (out_of_range&)
+            {
+                return default_value;
+            }
+        }
+
+        JSON_THROW(type_error::create(306, "cannot use value() with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief overload for a default value of type const char*
+    @copydoc basic_json::value(const json_pointer&, ValueType) const
+    */
+    string_t value(const json_pointer& ptr, const char* default_value) const
+    {
+        return value(ptr, string_t(default_value));
+    }
+
+    /*!
+    @brief access the first element
+
+    Returns a reference to the first element in the container. For a JSON
+    container `c`, the expression `c.front()` is equivalent to `*c.begin()`.
+
+    @return In case of a structured type (array or object), a reference to the
+    first element is returned. In case of number, string, or boolean values, a
+    reference to the value is returned.
+
+    @complexity Constant.
+
+    @pre The JSON value must not be `null` (would throw `std::out_of_range`)
+    or an empty array or object (undefined behavior, **guarded by
+    assertions**).
+    @post The JSON value remains unchanged.
+
+    @throw invalid_iterator.214 when called on `null` value
+
+    @liveexample{The following code shows an example for `front()`.,front}
+
+    @sa @ref back() -- access the last element
+
+    @since version 1.0.0
+    */
+    reference front()
+    {
+        return *begin();
+    }
+
+    /*!
+    @copydoc basic_json::front()
+    */
+    const_reference front() const
+    {
+        return *cbegin();
+    }
+
+    /*!
+    @brief access the last element
+
+    Returns a reference to the last element in the container. For a JSON
+    container `c`, the expression `c.back()` is equivalent to
+    @code {.cpp}
+    auto tmp = c.end();
+    --tmp;
+    return *tmp;
+    @endcode
+
+    @return In case of a structured type (array or object), a reference to the
+    last element is returned. In case of number, string, or boolean values, a
+    reference to the value is returned.
+
+    @complexity Constant.
+
+    @pre The JSON value must not be `null` (would throw `std::out_of_range`)
+    or an empty array or object (undefined behavior, **guarded by
+    assertions**).
+    @post The JSON value remains unchanged.
+
+    @throw invalid_iterator.214 when called on a `null` value. See example
+    below.
+
+    @liveexample{The following code shows an example for `back()`.,back}
+
+    @sa @ref front() -- access the first element
+
+    @since version 1.0.0
+    */
+    reference back()
+    {
+        auto tmp = end();
+        --tmp;
+        return *tmp;
+    }
+
+    /*!
+    @copydoc basic_json::back()
+    */
+    const_reference back() const
+    {
+        auto tmp = cend();
+        --tmp;
+        return *tmp;
+    }
+
+    /*!
+    @brief remove element given an iterator
+
+    Removes the element specified by iterator @a pos. The iterator @a pos must
+    be valid and dereferenceable. Thus the `end()` iterator (which is valid,
+    but is not dereferenceable) cannot be used as a value for @a pos.
+
+    If called on a primitive type other than `null`, the resulting JSON value
+    will be `null`.
+
+    @param[in] pos iterator to the element to remove
+    @return Iterator following the last removed element. If the iterator @a
+    pos refers to the last element, the `end()` iterator is returned.
+
+    @tparam IteratorType an @ref iterator or @ref const_iterator
+
+    @post Invalidates iterators and references at or after the point of the
+    erase, including the `end()` iterator.
+
+    @throw type_error.307 if called on a `null` value; example: `"cannot use
+    erase() with null"`
+    @throw invalid_iterator.202 if called on an iterator which does not belong
+    to the current JSON value; example: `"iterator does not fit current
+    value"`
+    @throw invalid_iterator.205 if called on a primitive type with invalid
+    iterator (i.e., any iterator which is not `begin()`); example: `"iterator
+    out of range"`
+
+    @complexity The complexity depends on the type:
+    - objects: amortized constant
+    - arrays: linear in distance between @a pos and the end of the container
+    - strings: linear in the length of the string
+    - other types: constant
+
+    @liveexample{The example shows the result of `erase()` for different JSON
+    types.,erase__IteratorType}
+
+    @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
+    the given range
+    @sa @ref erase(const typename object_t::key_type&) -- removes the element
+    from an object at the given key
+    @sa @ref erase(const size_type) -- removes the element from an array at
+    the given index
+
+    @since version 1.0.0
+    */
+    template<class IteratorType, typename std::enable_if<
+                 std::is_same<IteratorType, typename basic_json_t::iterator>::value or
+                 std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int>::type
+             = 0>
+    IteratorType erase(IteratorType pos)
+    {
+        // make sure iterator fits the current value
+        if (JSON_UNLIKELY(this != pos.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value"));
+        }
+
+        IteratorType result = end();
+
+        switch (m_type)
+        {
+            case value_t::boolean:
+            case value_t::number_float:
+            case value_t::number_integer:
+            case value_t::number_unsigned:
+            case value_t::string:
+            {
+                if (JSON_UNLIKELY(not pos.m_it.primitive_iterator.is_begin()))
+                {
+                    JSON_THROW(invalid_iterator::create(205, "iterator out of range"));
+                }
+
+                if (is_string())
+                {
+                    AllocatorType<string_t> alloc;
+                    std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.string);
+                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.string, 1);
+                    m_value.string = nullptr;
+                }
+
+                m_type = value_t::null;
+                assert_invariant();
+                break;
+            }
+
+            case value_t::object:
+            {
+                result.m_it.object_iterator = m_value.object->erase(pos.m_it.object_iterator);
+                break;
+            }
+
+            case value_t::array:
+            {
+                result.m_it.array_iterator = m_value.array->erase(pos.m_it.array_iterator);
+                break;
+            }
+
+            default:
+                JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name())));
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief remove elements given an iterator range
+
+    Removes the element specified by the range `[first; last)`. The iterator
+    @a first does not need to be dereferenceable if `first == last`: erasing
+    an empty range is a no-op.
+
+    If called on a primitive type other than `null`, the resulting JSON value
+    will be `null`.
+
+    @param[in] first iterator to the beginning of the range to remove
+    @param[in] last iterator past the end of the range to remove
+    @return Iterator following the last removed element. If the iterator @a
+    second refers to the last element, the `end()` iterator is returned.
+
+    @tparam IteratorType an @ref iterator or @ref const_iterator
+
+    @post Invalidates iterators and references at or after the point of the
+    erase, including the `end()` iterator.
+
+    @throw type_error.307 if called on a `null` value; example: `"cannot use
+    erase() with null"`
+    @throw invalid_iterator.203 if called on iterators which does not belong
+    to the current JSON value; example: `"iterators do not fit current value"`
+    @throw invalid_iterator.204 if called on a primitive type with invalid
+    iterators (i.e., if `first != begin()` and `last != end()`); example:
+    `"iterators out of range"`
+
+    @complexity The complexity depends on the type:
+    - objects: `log(size()) + std::distance(first, last)`
+    - arrays: linear in the distance between @a first and @a last, plus linear
+      in the distance between @a last and end of the container
+    - strings: linear in the length of the string
+    - other types: constant
+
+    @liveexample{The example shows the result of `erase()` for different JSON
+    types.,erase__IteratorType_IteratorType}
+
+    @sa @ref erase(IteratorType) -- removes the element at a given position
+    @sa @ref erase(const typename object_t::key_type&) -- removes the element
+    from an object at the given key
+    @sa @ref erase(const size_type) -- removes the element from an array at
+    the given index
+
+    @since version 1.0.0
+    */
+    template<class IteratorType, typename std::enable_if<
+                 std::is_same<IteratorType, typename basic_json_t::iterator>::value or
+                 std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int>::type
+             = 0>
+    IteratorType erase(IteratorType first, IteratorType last)
+    {
+        // make sure iterator fits the current value
+        if (JSON_UNLIKELY(this != first.m_object or this != last.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(203, "iterators do not fit current value"));
+        }
+
+        IteratorType result = end();
+
+        switch (m_type)
+        {
+            case value_t::boolean:
+            case value_t::number_float:
+            case value_t::number_integer:
+            case value_t::number_unsigned:
+            case value_t::string:
+            {
+                if (JSON_LIKELY(not first.m_it.primitive_iterator.is_begin()
+                                or not last.m_it.primitive_iterator.is_end()))
+                {
+                    JSON_THROW(invalid_iterator::create(204, "iterators out of range"));
+                }
+
+                if (is_string())
+                {
+                    AllocatorType<string_t> alloc;
+                    std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.string);
+                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.string, 1);
+                    m_value.string = nullptr;
+                }
+
+                m_type = value_t::null;
+                assert_invariant();
+                break;
+            }
+
+            case value_t::object:
+            {
+                result.m_it.object_iterator = m_value.object->erase(first.m_it.object_iterator,
+                                              last.m_it.object_iterator);
+                break;
+            }
+
+            case value_t::array:
+            {
+                result.m_it.array_iterator = m_value.array->erase(first.m_it.array_iterator,
+                                             last.m_it.array_iterator);
+                break;
+            }
+
+            default:
+                JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name())));
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief remove element from a JSON object given a key
+
+    Removes elements from a JSON object with the key value @a key.
+
+    @param[in] key value of the elements to remove
+
+    @return Number of elements removed. If @a ObjectType is the default
+    `std::map` type, the return value will always be `0` (@a key was not
+    found) or `1` (@a key was found).
+
+    @post References and iterators to the erased elements are invalidated.
+    Other references and iterators are not affected.
+
+    @throw type_error.307 when called on a type other than JSON object;
+    example: `"cannot use erase() with null"`
+
+    @complexity `log(size()) + count(key)`
+
+    @liveexample{The example shows the effect of `erase()`.,erase__key_type}
+
+    @sa @ref erase(IteratorType) -- removes the element at a given position
+    @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
+    the given range
+    @sa @ref erase(const size_type) -- removes the element from an array at
+    the given index
+
+    @since version 1.0.0
+    */
+    size_type erase(const typename object_t::key_type& key)
+    {
+        // this erase only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            return m_value.object->erase(key);
+        }
+
+        JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief remove element from a JSON array given an index
+
+    Removes element from a JSON array at the index @a idx.
+
+    @param[in] idx index of the element to remove
+
+    @throw type_error.307 when called on a type other than JSON object;
+    example: `"cannot use erase() with null"`
+    @throw out_of_range.401 when `idx >= size()`; example: `"array index 17
+    is out of range"`
+
+    @complexity Linear in distance between @a idx and the end of the container.
+
+    @liveexample{The example shows the effect of `erase()`.,erase__size_type}
+
+    @sa @ref erase(IteratorType) -- removes the element at a given position
+    @sa @ref erase(IteratorType, IteratorType) -- removes the elements in
+    the given range
+    @sa @ref erase(const typename object_t::key_type&) -- removes the element
+    from an object at the given key
+
+    @since version 1.0.0
+    */
+    void erase(const size_type idx)
+    {
+        // this erase only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            if (JSON_UNLIKELY(idx >= size()))
+            {
+                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range"));
+            }
+
+            m_value.array->erase(m_value.array->begin() + static_cast<difference_type>(idx));
+        }
+        else
+        {
+            JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name())));
+        }
+    }
+
+    /// @}
+
+
+    ////////////
+    // lookup //
+    ////////////
+
+    /// @name lookup
+    /// @{
+
+    /*!
+    @brief find an element in a JSON object
+
+    Finds an element in a JSON object with key equivalent to @a key. If the
+    element is not found or the JSON value is not an object, end() is
+    returned.
+
+    @note This method always returns @ref end() when executed on a JSON type
+          that is not an object.
+
+    @param[in] key key value of the element to search for.
+
+    @return Iterator to an element with key equivalent to @a key. If no such
+    element is found or the JSON value is not an object, past-the-end (see
+    @ref end()) iterator is returned.
+
+    @complexity Logarithmic in the size of the JSON object.
+
+    @liveexample{The example shows how `find()` is used.,find__key_type}
+
+    @since version 1.0.0
+    */
+    template<typename KeyT>
+    iterator find(KeyT&& key)
+    {
+        auto result = end();
+
+        if (is_object())
+        {
+            result.m_it.object_iterator = m_value.object->find(std::forward<KeyT>(key));
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief find an element in a JSON object
+    @copydoc find(KeyT&&)
+    */
+    template<typename KeyT>
+    const_iterator find(KeyT&& key) const
+    {
+        auto result = cend();
+
+        if (is_object())
+        {
+            result.m_it.object_iterator = m_value.object->find(std::forward<KeyT>(key));
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief returns the number of occurrences of a key in a JSON object
+
+    Returns the number of elements with key @a key. If ObjectType is the
+    default `std::map` type, the return value will always be `0` (@a key was
+    not found) or `1` (@a key was found).
+
+    @note This method always returns `0` when executed on a JSON type that is
+          not an object.
+
+    @param[in] key key value of the element to count
+
+    @return Number of elements with key @a key. If the JSON value is not an
+    object, the return value will be `0`.
+
+    @complexity Logarithmic in the size of the JSON object.
+
+    @liveexample{The example shows how `count()` is used.,count}
+
+    @since version 1.0.0
+    */
+    template<typename KeyT>
+    size_type count(KeyT&& key) const
+    {
+        // return 0 for all nonobject types
+        return is_object() ? m_value.object->count(std::forward<KeyT>(key)) : 0;
+    }
+
+    /// @}
+
+
+    ///////////////
+    // iterators //
+    ///////////////
+
+    /// @name iterators
+    /// @{
+
+    /*!
+    @brief returns an iterator to the first element
+
+    Returns an iterator to the first element.
+
+    @image html range-begin-end.svg "Illustration from cppreference.com"
+
+    @return iterator to the first element
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+
+    @liveexample{The following code shows an example for `begin()`.,begin}
+
+    @sa @ref cbegin() -- returns a const iterator to the beginning
+    @sa @ref end() -- returns an iterator to the end
+    @sa @ref cend() -- returns a const iterator to the end
+
+    @since version 1.0.0
+    */
+    iterator begin() noexcept
+    {
+        iterator result(this);
+        result.set_begin();
+        return result;
+    }
+
+    /*!
+    @copydoc basic_json::cbegin()
+    */
+    const_iterator begin() const noexcept
+    {
+        return cbegin();
+    }
+
+    /*!
+    @brief returns a const iterator to the first element
+
+    Returns a const iterator to the first element.
+
+    @image html range-begin-end.svg "Illustration from cppreference.com"
+
+    @return const iterator to the first element
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `const_cast<const basic_json&>(*this).begin()`.
+
+    @liveexample{The following code shows an example for `cbegin()`.,cbegin}
+
+    @sa @ref begin() -- returns an iterator to the beginning
+    @sa @ref end() -- returns an iterator to the end
+    @sa @ref cend() -- returns a const iterator to the end
+
+    @since version 1.0.0
+    */
+    const_iterator cbegin() const noexcept
+    {
+        const_iterator result(this);
+        result.set_begin();
+        return result;
+    }
+
+    /*!
+    @brief returns an iterator to one past the last element
+
+    Returns an iterator to one past the last element.
+
+    @image html range-begin-end.svg "Illustration from cppreference.com"
+
+    @return iterator one past the last element
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+
+    @liveexample{The following code shows an example for `end()`.,end}
+
+    @sa @ref cend() -- returns a const iterator to the end
+    @sa @ref begin() -- returns an iterator to the beginning
+    @sa @ref cbegin() -- returns a const iterator to the beginning
+
+    @since version 1.0.0
+    */
+    iterator end() noexcept
+    {
+        iterator result(this);
+        result.set_end();
+        return result;
+    }
+
+    /*!
+    @copydoc basic_json::cend()
+    */
+    const_iterator end() const noexcept
+    {
+        return cend();
+    }
+
+    /*!
+    @brief returns a const iterator to one past the last element
+
+    Returns a const iterator to one past the last element.
+
+    @image html range-begin-end.svg "Illustration from cppreference.com"
+
+    @return const iterator one past the last element
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `const_cast<const basic_json&>(*this).end()`.
+
+    @liveexample{The following code shows an example for `cend()`.,cend}
+
+    @sa @ref end() -- returns an iterator to the end
+    @sa @ref begin() -- returns an iterator to the beginning
+    @sa @ref cbegin() -- returns a const iterator to the beginning
+
+    @since version 1.0.0
+    */
+    const_iterator cend() const noexcept
+    {
+        const_iterator result(this);
+        result.set_end();
+        return result;
+    }
+
+    /*!
+    @brief returns an iterator to the reverse-beginning
+
+    Returns an iterator to the reverse-beginning; that is, the last element.
+
+    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `reverse_iterator(end())`.
+
+    @liveexample{The following code shows an example for `rbegin()`.,rbegin}
+
+    @sa @ref crbegin() -- returns a const reverse iterator to the beginning
+    @sa @ref rend() -- returns a reverse iterator to the end
+    @sa @ref crend() -- returns a const reverse iterator to the end
+
+    @since version 1.0.0
+    */
+    reverse_iterator rbegin() noexcept
+    {
+        return reverse_iterator(end());
+    }
+
+    /*!
+    @copydoc basic_json::crbegin()
+    */
+    const_reverse_iterator rbegin() const noexcept
+    {
+        return crbegin();
+    }
+
+    /*!
+    @brief returns an iterator to the reverse-end
+
+    Returns an iterator to the reverse-end; that is, one before the first
+    element.
+
+    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `reverse_iterator(begin())`.
+
+    @liveexample{The following code shows an example for `rend()`.,rend}
+
+    @sa @ref crend() -- returns a const reverse iterator to the end
+    @sa @ref rbegin() -- returns a reverse iterator to the beginning
+    @sa @ref crbegin() -- returns a const reverse iterator to the beginning
+
+    @since version 1.0.0
+    */
+    reverse_iterator rend() noexcept
+    {
+        return reverse_iterator(begin());
+    }
+
+    /*!
+    @copydoc basic_json::crend()
+    */
+    const_reverse_iterator rend() const noexcept
+    {
+        return crend();
+    }
+
+    /*!
+    @brief returns a const reverse iterator to the last element
+
+    Returns a const iterator to the reverse-beginning; that is, the last
+    element.
+
+    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `const_cast<const basic_json&>(*this).rbegin()`.
+
+    @liveexample{The following code shows an example for `crbegin()`.,crbegin}
+
+    @sa @ref rbegin() -- returns a reverse iterator to the beginning
+    @sa @ref rend() -- returns a reverse iterator to the end
+    @sa @ref crend() -- returns a const reverse iterator to the end
+
+    @since version 1.0.0
+    */
+    const_reverse_iterator crbegin() const noexcept
+    {
+        return const_reverse_iterator(cend());
+    }
+
+    /*!
+    @brief returns a const reverse iterator to one before the first
+
+    Returns a const reverse iterator to the reverse-end; that is, one before
+    the first element.
+
+    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
+
+    @complexity Constant.
+
+    @requirement This function helps `basic_json` satisfying the
+    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `const_cast<const basic_json&>(*this).rend()`.
+
+    @liveexample{The following code shows an example for `crend()`.,crend}
+
+    @sa @ref rend() -- returns a reverse iterator to the end
+    @sa @ref rbegin() -- returns a reverse iterator to the beginning
+    @sa @ref crbegin() -- returns a const reverse iterator to the beginning
+
+    @since version 1.0.0
+    */
+    const_reverse_iterator crend() const noexcept
+    {
+        return const_reverse_iterator(cbegin());
+    }
+
+  public:
+    /*!
+    @brief wrapper to access iterator member functions in range-based for
+
+    This function allows to access @ref iterator::key() and @ref
+    iterator::value() during range-based for loops. In these loops, a
+    reference to the JSON values is returned, so there is no access to the
+    underlying iterator.
+
+    For loop without iterator_wrapper:
+
+    @code{cpp}
+    for (auto it = j_object.begin(); it != j_object.end(); ++it)
+    {
+        std::cout << "key: " << it.key() << ", value:" << it.value() << '\n';
+    }
+    @endcode
+
+    Range-based for loop without iterator proxy:
+
+    @code{cpp}
+    for (auto it : j_object)
+    {
+        // "it" is of type json::reference and has no key() member
+        std::cout << "value: " << it << '\n';
+    }
+    @endcode
+
+    Range-based for loop with iterator proxy:
+
+    @code{cpp}
+    for (auto it : json::iterator_wrapper(j_object))
+    {
+        std::cout << "key: " << it.key() << ", value:" << it.value() << '\n';
+    }
+    @endcode
+
+    @note When iterating over an array, `key()` will return the index of the
+          element as string (see example).
+
+    @param[in] ref  reference to a JSON value
+    @return iteration proxy object wrapping @a ref with an interface to use in
+            range-based for loops
+
+    @liveexample{The following code shows how the wrapper is used,iterator_wrapper}
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Constant.
+
+    @note The name of this function is not yet final and may change in the
+    future.
+
+    @deprecated This stream operator is deprecated and will be removed in
+                future 4.0.0 of the library. Please use @ref items() instead;
+                that is, replace `json::iterator_wrapper(j)` with `j.items()`.
+    */
+    JSON_DEPRECATED
+    static iteration_proxy<iterator> iterator_wrapper(reference ref) noexcept
+    {
+        return ref.items();
+    }
+
+    /*!
+    @copydoc iterator_wrapper(reference)
+    */
+    JSON_DEPRECATED
+    static iteration_proxy<const_iterator> iterator_wrapper(const_reference ref) noexcept
+    {
+        return ref.items();
+    }
+
+    /*!
+    @brief helper to access iterator member functions in range-based for
+
+    This function allows to access @ref iterator::key() and @ref
+    iterator::value() during range-based for loops. In these loops, a
+    reference to the JSON values is returned, so there is no access to the
+    underlying iterator.
+
+    For loop without `items()` function:
+
+    @code{cpp}
+    for (auto it = j_object.begin(); it != j_object.end(); ++it)
+    {
+        std::cout << "key: " << it.key() << ", value:" << it.value() << '\n';
+    }
+    @endcode
+
+    Range-based for loop without `items()` function:
+
+    @code{cpp}
+    for (auto it : j_object)
+    {
+        // "it" is of type json::reference and has no key() member
+        std::cout << "value: " << it << '\n';
+    }
+    @endcode
+
+    Range-based for loop with `items()` function:
+
+    @code{cpp}
+    for (auto& el : j_object.items())
+    {
+        std::cout << "key: " << el.key() << ", value:" << el.value() << '\n';
+    }
+    @endcode
+
+    The `items()` function also allows to use
+    [structured bindings](https://en.cppreference.com/w/cpp/language/structured_binding)
+    (C++17):
+
+    @code{cpp}
+    for (auto& [key, val] : j_object.items())
+    {
+        std::cout << "key: " << key << ", value:" << val << '\n';
+    }
+    @endcode
+
+    @note When iterating over an array, `key()` will return the index of the
+          element as string (see example). For primitive types (e.g., numbers),
+          `key()` returns an empty string.
+
+    @return iteration proxy object wrapping @a ref with an interface to use in
+            range-based for loops
+
+    @liveexample{The following code shows how the function is used.,items}
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Constant.
+
+    @since version 3.1.0, structured bindings support since 3.5.0.
+    */
+    iteration_proxy<iterator> items() noexcept
+    {
+        return iteration_proxy<iterator>(*this);
+    }
+
+    /*!
+    @copydoc items()
+    */
+    iteration_proxy<const_iterator> items() const noexcept
+    {
+        return iteration_proxy<const_iterator>(*this);
+    }
+
+    /// @}
+
+
+    //////////////
+    // capacity //
+    //////////////
+
+    /// @name capacity
+    /// @{
+
+    /*!
+    @brief checks whether the container is empty.
+
+    Checks if a JSON value has no elements (i.e. whether its @ref size is `0`).
+
+    @return The return value depends on the different types and is
+            defined as follows:
+            Value type  | return value
+            ----------- | -------------
+            null        | `true`
+            boolean     | `false`
+            string      | `false`
+            number      | `false`
+            object      | result of function `object_t::empty()`
+            array       | result of function `array_t::empty()`
+
+    @liveexample{The following code uses `empty()` to check if a JSON
+    object contains any elements.,empty}
+
+    @complexity Constant, as long as @ref array_t and @ref object_t satisfy
+    the Container concept; that is, their `empty()` functions have constant
+    complexity.
+
+    @iterators No changes.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @note This function does not return whether a string stored as JSON value
+    is empty - it returns whether the JSON container itself is empty which is
+    false in the case of a string.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `begin() == end()`.
+
+    @sa @ref size() -- returns the number of elements
+
+    @since version 1.0.0
+    */
+    bool empty() const noexcept
+    {
+        switch (m_type)
+        {
+            case value_t::null:
+            {
+                // null values are empty
+                return true;
+            }
+
+            case value_t::array:
+            {
+                // delegate call to array_t::empty()
+                return m_value.array->empty();
+            }
+
+            case value_t::object:
+            {
+                // delegate call to object_t::empty()
+                return m_value.object->empty();
+            }
+
+            default:
+            {
+                // all other types are nonempty
+                return false;
+            }
+        }
+    }
+
+    /*!
+    @brief returns the number of elements
+
+    Returns the number of elements in a JSON value.
+
+    @return The return value depends on the different types and is
+            defined as follows:
+            Value type  | return value
+            ----------- | -------------
+            null        | `0`
+            boolean     | `1`
+            string      | `1`
+            number      | `1`
+            object      | result of function object_t::size()
+            array       | result of function array_t::size()
+
+    @liveexample{The following code calls `size()` on the different value
+    types.,size}
+
+    @complexity Constant, as long as @ref array_t and @ref object_t satisfy
+    the Container concept; that is, their size() functions have constant
+    complexity.
+
+    @iterators No changes.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @note This function does not return the length of a string stored as JSON
+    value - it returns the number of elements in the JSON value which is 1 in
+    the case of a string.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of `std::distance(begin(), end())`.
+
+    @sa @ref empty() -- checks whether the container is empty
+    @sa @ref max_size() -- returns the maximal number of elements
+
+    @since version 1.0.0
+    */
+    size_type size() const noexcept
+    {
+        switch (m_type)
+        {
+            case value_t::null:
+            {
+                // null values are empty
+                return 0;
+            }
+
+            case value_t::array:
+            {
+                // delegate call to array_t::size()
+                return m_value.array->size();
+            }
+
+            case value_t::object:
+            {
+                // delegate call to object_t::size()
+                return m_value.object->size();
+            }
+
+            default:
+            {
+                // all other types have size 1
+                return 1;
+            }
+        }
+    }
+
+    /*!
+    @brief returns the maximum possible number of elements
+
+    Returns the maximum number of elements a JSON value is able to hold due to
+    system or library implementation limitations, i.e. `std::distance(begin(),
+    end())` for the JSON value.
+
+    @return The return value depends on the different types and is
+            defined as follows:
+            Value type  | return value
+            ----------- | -------------
+            null        | `0` (same as `size()`)
+            boolean     | `1` (same as `size()`)
+            string      | `1` (same as `size()`)
+            number      | `1` (same as `size()`)
+            object      | result of function `object_t::max_size()`
+            array       | result of function `array_t::max_size()`
+
+    @liveexample{The following code calls `max_size()` on the different value
+    types. Note the output is implementation specific.,max_size}
+
+    @complexity Constant, as long as @ref array_t and @ref object_t satisfy
+    the Container concept; that is, their `max_size()` functions have constant
+    complexity.
+
+    @iterators No changes.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @requirement This function helps `basic_json` satisfying the
+    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
+    requirements:
+    - The complexity is constant.
+    - Has the semantics of returning `b.size()` where `b` is the largest
+      possible JSON value.
+
+    @sa @ref size() -- returns the number of elements
+
+    @since version 1.0.0
+    */
+    size_type max_size() const noexcept
+    {
+        switch (m_type)
+        {
+            case value_t::array:
+            {
+                // delegate call to array_t::max_size()
+                return m_value.array->max_size();
+            }
+
+            case value_t::object:
+            {
+                // delegate call to object_t::max_size()
+                return m_value.object->max_size();
+            }
+
+            default:
+            {
+                // all other types have max_size() == size()
+                return size();
+            }
+        }
+    }
+
+    /// @}
+
+
+    ///////////////
+    // modifiers //
+    ///////////////
+
+    /// @name modifiers
+    /// @{
+
+    /*!
+    @brief clears the contents
+
+    Clears the content of a JSON value and resets it to the default value as
+    if @ref basic_json(value_t) would have been called with the current value
+    type from @ref type():
+
+    Value type  | initial value
+    ----------- | -------------
+    null        | `null`
+    boolean     | `false`
+    string      | `""`
+    number      | `0`
+    object      | `{}`
+    array       | `[]`
+
+    @post Has the same effect as calling
+    @code {.cpp}
+    *this = basic_json(type());
+    @endcode
+
+    @liveexample{The example below shows the effect of `clear()` to different
+    JSON types.,clear}
+
+    @complexity Linear in the size of the JSON value.
+
+    @iterators All iterators, pointers and references related to this container
+               are invalidated.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @sa @ref basic_json(value_t) -- constructor that creates an object with the
+        same value than calling `clear()`
+
+    @since version 1.0.0
+    */
+    void clear() noexcept
+    {
+        switch (m_type)
+        {
+            case value_t::number_integer:
+            {
+                m_value.number_integer = 0;
+                break;
+            }
+
+            case value_t::number_unsigned:
+            {
+                m_value.number_unsigned = 0;
+                break;
+            }
+
+            case value_t::number_float:
+            {
+                m_value.number_float = 0.0;
+                break;
+            }
+
+            case value_t::boolean:
+            {
+                m_value.boolean = false;
+                break;
+            }
+
+            case value_t::string:
+            {
+                m_value.string->clear();
+                break;
+            }
+
+            case value_t::array:
+            {
+                m_value.array->clear();
+                break;
+            }
+
+            case value_t::object:
+            {
+                m_value.object->clear();
+                break;
+            }
+
+            default:
+                break;
+        }
+    }
+
+    /*!
+    @brief add an object to an array
+
+    Appends the given element @a val to the end of the JSON value. If the
+    function is called on a JSON null value, an empty array is created before
+    appending @a val.
+
+    @param[in] val the value to add to the JSON array
+
+    @throw type_error.308 when called on a type other than JSON array or
+    null; example: `"cannot use push_back() with number"`
+
+    @complexity Amortized constant.
+
+    @liveexample{The example shows how `push_back()` and `+=` can be used to
+    add elements to a JSON array. Note how the `null` value was silently
+    converted to a JSON array.,push_back}
+
+    @since version 1.0.0
+    */
+    void push_back(basic_json&& val)
+    {
+        // push_back only works for null objects or arrays
+        if (JSON_UNLIKELY(not(is_null() or is_array())))
+        {
+            JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name())));
+        }
+
+        // transform null object into an array
+        if (is_null())
+        {
+            m_type = value_t::array;
+            m_value = value_t::array;
+            assert_invariant();
+        }
+
+        // add element to array (move semantics)
+        m_value.array->push_back(std::move(val));
+        // invalidate object
+        val.m_type = value_t::null;
+    }
+
+    /*!
+    @brief add an object to an array
+    @copydoc push_back(basic_json&&)
+    */
+    reference operator+=(basic_json&& val)
+    {
+        push_back(std::move(val));
+        return *this;
+    }
+
+    /*!
+    @brief add an object to an array
+    @copydoc push_back(basic_json&&)
+    */
+    void push_back(const basic_json& val)
+    {
+        // push_back only works for null objects or arrays
+        if (JSON_UNLIKELY(not(is_null() or is_array())))
+        {
+            JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name())));
+        }
+
+        // transform null object into an array
+        if (is_null())
+        {
+            m_type = value_t::array;
+            m_value = value_t::array;
+            assert_invariant();
+        }
+
+        // add element to array
+        m_value.array->push_back(val);
+    }
+
+    /*!
+    @brief add an object to an array
+    @copydoc push_back(basic_json&&)
+    */
+    reference operator+=(const basic_json& val)
+    {
+        push_back(val);
+        return *this;
+    }
+
+    /*!
+    @brief add an object to an object
+
+    Inserts the given element @a val to the JSON object. If the function is
+    called on a JSON null value, an empty object is created before inserting
+    @a val.
+
+    @param[in] val the value to add to the JSON object
+
+    @throw type_error.308 when called on a type other than JSON object or
+    null; example: `"cannot use push_back() with number"`
+
+    @complexity Logarithmic in the size of the container, O(log(`size()`)).
+
+    @liveexample{The example shows how `push_back()` and `+=` can be used to
+    add elements to a JSON object. Note how the `null` value was silently
+    converted to a JSON object.,push_back__object_t__value}
+
+    @since version 1.0.0
+    */
+    void push_back(const typename object_t::value_type& val)
+    {
+        // push_back only works for null objects or objects
+        if (JSON_UNLIKELY(not(is_null() or is_object())))
+        {
+            JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name())));
+        }
+
+        // transform null object into an object
+        if (is_null())
+        {
+            m_type = value_t::object;
+            m_value = value_t::object;
+            assert_invariant();
+        }
+
+        // add element to array
+        m_value.object->insert(val);
+    }
+
+    /*!
+    @brief add an object to an object
+    @copydoc push_back(const typename object_t::value_type&)
+    */
+    reference operator+=(const typename object_t::value_type& val)
+    {
+        push_back(val);
+        return *this;
+    }
+
+    /*!
+    @brief add an object to an object
+
+    This function allows to use `push_back` with an initializer list. In case
+
+    1. the current value is an object,
+    2. the initializer list @a init contains only two elements, and
+    3. the first element of @a init is a string,
+
+    @a init is converted into an object element and added using
+    @ref push_back(const typename object_t::value_type&). Otherwise, @a init
+    is converted to a JSON value and added using @ref push_back(basic_json&&).
+
+    @param[in] init  an initializer list
+
+    @complexity Linear in the size of the initializer list @a init.
+
+    @note This function is required to resolve an ambiguous overload error,
+          because pairs like `{"key", "value"}` can be both interpreted as
+          `object_t::value_type` or `std::initializer_list<basic_json>`, see
+          https://github.com/nlohmann/json/issues/235 for more information.
+
+    @liveexample{The example shows how initializer lists are treated as
+    objects when possible.,push_back__initializer_list}
+    */
+    void push_back(initializer_list_t init)
+    {
+        if (is_object() and init.size() == 2 and (*init.begin())->is_string())
+        {
+            basic_json&& key = init.begin()->moved_or_copied();
+            push_back(typename object_t::value_type(
+                          std::move(key.get_ref<string_t&>()), (init.begin() + 1)->moved_or_copied()));
+        }
+        else
+        {
+            push_back(basic_json(init));
+        }
+    }
+
+    /*!
+    @brief add an object to an object
+    @copydoc push_back(initializer_list_t)
+    */
+    reference operator+=(initializer_list_t init)
+    {
+        push_back(init);
+        return *this;
+    }
+
+    /*!
+    @brief add an object to an array
+
+    Creates a JSON value from the passed parameters @a args to the end of the
+    JSON value. If the function is called on a JSON null value, an empty array
+    is created before appending the value created from @a args.
+
+    @param[in] args arguments to forward to a constructor of @ref basic_json
+    @tparam Args compatible types to create a @ref basic_json object
+
+    @throw type_error.311 when called on a type other than JSON array or
+    null; example: `"cannot use emplace_back() with number"`
+
+    @complexity Amortized constant.
+
+    @liveexample{The example shows how `push_back()` can be used to add
+    elements to a JSON array. Note how the `null` value was silently converted
+    to a JSON array.,emplace_back}
+
+    @since version 2.0.8
+    */
+    template<class... Args>
+    void emplace_back(Args&& ... args)
+    {
+        // emplace_back only works for null objects or arrays
+        if (JSON_UNLIKELY(not(is_null() or is_array())))
+        {
+            JSON_THROW(type_error::create(311, "cannot use emplace_back() with " + std::string(type_name())));
+        }
+
+        // transform null object into an array
+        if (is_null())
+        {
+            m_type = value_t::array;
+            m_value = value_t::array;
+            assert_invariant();
+        }
+
+        // add element to array (perfect forwarding)
+        m_value.array->emplace_back(std::forward<Args>(args)...);
+    }
+
+    /*!
+    @brief add an object to an object if key does not exist
+
+    Inserts a new element into a JSON object constructed in-place with the
+    given @a args if there is no element with the key in the container. If the
+    function is called on a JSON null value, an empty object is created before
+    appending the value created from @a args.
+
+    @param[in] args arguments to forward to a constructor of @ref basic_json
+    @tparam Args compatible types to create a @ref basic_json object
+
+    @return a pair consisting of an iterator to the inserted element, or the
+            already-existing element if no insertion happened, and a bool
+            denoting whether the insertion took place.
+
+    @throw type_error.311 when called on a type other than JSON object or
+    null; example: `"cannot use emplace() with number"`
+
+    @complexity Logarithmic in the size of the container, O(log(`size()`)).
+
+    @liveexample{The example shows how `emplace()` can be used to add elements
+    to a JSON object. Note how the `null` value was silently converted to a
+    JSON object. Further note how no value is added if there was already one
+    value stored with the same key.,emplace}
+
+    @since version 2.0.8
+    */
+    template<class... Args>
+    std::pair<iterator, bool> emplace(Args&& ... args)
+    {
+        // emplace only works for null objects or arrays
+        if (JSON_UNLIKELY(not(is_null() or is_object())))
+        {
+            JSON_THROW(type_error::create(311, "cannot use emplace() with " + std::string(type_name())));
+        }
+
+        // transform null object into an object
+        if (is_null())
+        {
+            m_type = value_t::object;
+            m_value = value_t::object;
+            assert_invariant();
+        }
+
+        // add element to array (perfect forwarding)
+        auto res = m_value.object->emplace(std::forward<Args>(args)...);
+        // create result iterator and set iterator to the result of emplace
+        auto it = begin();
+        it.m_it.object_iterator = res.first;
+
+        // return pair of iterator and boolean
+        return {it, res.second};
+    }
+
+    /// Helper for insertion of an iterator
+    /// @note: This uses std::distance to support GCC 4.8,
+    ///        see https://github.com/nlohmann/json/pull/1257
+    template<typename... Args>
+    iterator insert_iterator(const_iterator pos, Args&& ... args)
+    {
+        iterator result(this);
+        assert(m_value.array != nullptr);
+
+        auto insert_pos = std::distance(m_value.array->begin(), pos.m_it.array_iterator);
+        m_value.array->insert(pos.m_it.array_iterator, std::forward<Args>(args)...);
+        result.m_it.array_iterator = m_value.array->begin() + insert_pos;
+
+        // This could have been written as:
+        // result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, cnt, val);
+        // but the return value of insert is missing in GCC 4.8, so it is written this way instead.
+
+        return result;
+    }
+
+    /*!
+    @brief inserts element
+
+    Inserts element @a val before iterator @a pos.
+
+    @param[in] pos iterator before which the content will be inserted; may be
+    the end() iterator
+    @param[in] val element to insert
+    @return iterator pointing to the inserted @a val.
+
+    @throw type_error.309 if called on JSON values other than arrays;
+    example: `"cannot use insert() with string"`
+    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
+    example: `"iterator does not fit current value"`
+
+    @complexity Constant plus linear in the distance between @a pos and end of
+    the container.
+
+    @liveexample{The example shows how `insert()` is used.,insert}
+
+    @since version 1.0.0
+    */
+    iterator insert(const_iterator pos, const basic_json& val)
+    {
+        // insert only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            // check if iterator pos fits to this JSON value
+            if (JSON_UNLIKELY(pos.m_object != this))
+            {
+                JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value"));
+            }
+
+            // insert to array and return iterator
+            return insert_iterator(pos, val);
+        }
+
+        JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief inserts element
+    @copydoc insert(const_iterator, const basic_json&)
+    */
+    iterator insert(const_iterator pos, basic_json&& val)
+    {
+        return insert(pos, val);
+    }
+
+    /*!
+    @brief inserts elements
+
+    Inserts @a cnt copies of @a val before iterator @a pos.
+
+    @param[in] pos iterator before which the content will be inserted; may be
+    the end() iterator
+    @param[in] cnt number of copies of @a val to insert
+    @param[in] val element to insert
+    @return iterator pointing to the first element inserted, or @a pos if
+    `cnt==0`
+
+    @throw type_error.309 if called on JSON values other than arrays; example:
+    `"cannot use insert() with string"`
+    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
+    example: `"iterator does not fit current value"`
+
+    @complexity Linear in @a cnt plus linear in the distance between @a pos
+    and end of the container.
+
+    @liveexample{The example shows how `insert()` is used.,insert__count}
+
+    @since version 1.0.0
+    */
+    iterator insert(const_iterator pos, size_type cnt, const basic_json& val)
+    {
+        // insert only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            // check if iterator pos fits to this JSON value
+            if (JSON_UNLIKELY(pos.m_object != this))
+            {
+                JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value"));
+            }
+
+            // insert to array and return iterator
+            return insert_iterator(pos, cnt, val);
+        }
+
+        JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name())));
+    }
+
+    /*!
+    @brief inserts elements
+
+    Inserts elements from range `[first, last)` before iterator @a pos.
+
+    @param[in] pos iterator before which the content will be inserted; may be
+    the end() iterator
+    @param[in] first begin of the range of elements to insert
+    @param[in] last end of the range of elements to insert
+
+    @throw type_error.309 if called on JSON values other than arrays; example:
+    `"cannot use insert() with string"`
+    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
+    example: `"iterator does not fit current value"`
+    @throw invalid_iterator.210 if @a first and @a last do not belong to the
+    same JSON value; example: `"iterators do not fit"`
+    @throw invalid_iterator.211 if @a first or @a last are iterators into
+    container for which insert is called; example: `"passed iterators may not
+    belong to container"`
+
+    @return iterator pointing to the first element inserted, or @a pos if
+    `first==last`
+
+    @complexity Linear in `std::distance(first, last)` plus linear in the
+    distance between @a pos and end of the container.
+
+    @liveexample{The example shows how `insert()` is used.,insert__range}
+
+    @since version 1.0.0
+    */
+    iterator insert(const_iterator pos, const_iterator first, const_iterator last)
+    {
+        // insert only works for arrays
+        if (JSON_UNLIKELY(not is_array()))
+        {
+            JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name())));
+        }
+
+        // check if iterator pos fits to this JSON value
+        if (JSON_UNLIKELY(pos.m_object != this))
+        {
+            JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value"));
+        }
+
+        // check if range iterators belong to the same JSON object
+        if (JSON_UNLIKELY(first.m_object != last.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(210, "iterators do not fit"));
+        }
+
+        if (JSON_UNLIKELY(first.m_object == this))
+        {
+            JSON_THROW(invalid_iterator::create(211, "passed iterators may not belong to container"));
+        }
+
+        // insert to array and return iterator
+        return insert_iterator(pos, first.m_it.array_iterator, last.m_it.array_iterator);
+    }
+
+    /*!
+    @brief inserts elements
+
+    Inserts elements from initializer list @a ilist before iterator @a pos.
+
+    @param[in] pos iterator before which the content will be inserted; may be
+    the end() iterator
+    @param[in] ilist initializer list to insert the values from
+
+    @throw type_error.309 if called on JSON values other than arrays; example:
+    `"cannot use insert() with string"`
+    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
+    example: `"iterator does not fit current value"`
+
+    @return iterator pointing to the first element inserted, or @a pos if
+    `ilist` is empty
+
+    @complexity Linear in `ilist.size()` plus linear in the distance between
+    @a pos and end of the container.
+
+    @liveexample{The example shows how `insert()` is used.,insert__ilist}
+
+    @since version 1.0.0
+    */
+    iterator insert(const_iterator pos, initializer_list_t ilist)
+    {
+        // insert only works for arrays
+        if (JSON_UNLIKELY(not is_array()))
+        {
+            JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name())));
+        }
+
+        // check if iterator pos fits to this JSON value
+        if (JSON_UNLIKELY(pos.m_object != this))
+        {
+            JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value"));
+        }
+
+        // insert to array and return iterator
+        return insert_iterator(pos, ilist.begin(), ilist.end());
+    }
+
+    /*!
+    @brief inserts elements
+
+    Inserts elements from range `[first, last)`.
+
+    @param[in] first begin of the range of elements to insert
+    @param[in] last end of the range of elements to insert
+
+    @throw type_error.309 if called on JSON values other than objects; example:
+    `"cannot use insert() with string"`
+    @throw invalid_iterator.202 if iterator @a first or @a last does does not
+    point to an object; example: `"iterators first and last must point to
+    objects"`
+    @throw invalid_iterator.210 if @a first and @a last do not belong to the
+    same JSON value; example: `"iterators do not fit"`
+
+    @complexity Logarithmic: `O(N*log(size() + N))`, where `N` is the number
+    of elements to insert.
+
+    @liveexample{The example shows how `insert()` is used.,insert__range_object}
+
+    @since version 3.0.0
+    */
+    void insert(const_iterator first, const_iterator last)
+    {
+        // insert only works for objects
+        if (JSON_UNLIKELY(not is_object()))
+        {
+            JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name())));
+        }
+
+        // check if range iterators belong to the same JSON object
+        if (JSON_UNLIKELY(first.m_object != last.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(210, "iterators do not fit"));
+        }
+
+        // passed iterators must belong to objects
+        if (JSON_UNLIKELY(not first.m_object->is_object()))
+        {
+            JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects"));
+        }
+
+        m_value.object->insert(first.m_it.object_iterator, last.m_it.object_iterator);
+    }
+
+    /*!
+    @brief updates a JSON object from another object, overwriting existing keys
+
+    Inserts all values from JSON object @a j and overwrites existing keys.
+
+    @param[in] j  JSON object to read values from
+
+    @throw type_error.312 if called on JSON values other than objects; example:
+    `"cannot use update() with string"`
+
+    @complexity O(N*log(size() + N)), where N is the number of elements to
+                insert.
+
+    @liveexample{The example shows how `update()` is used.,update}
+
+    @sa https://docs.python.org/3.6/library/stdtypes.html#dict.update
+
+    @since version 3.0.0
+    */
+    void update(const_reference j)
+    {
+        // implicitly convert null value to an empty object
+        if (is_null())
+        {
+            m_type = value_t::object;
+            m_value.object = create<object_t>();
+            assert_invariant();
+        }
+
+        if (JSON_UNLIKELY(not is_object()))
+        {
+            JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(type_name())));
+        }
+        if (JSON_UNLIKELY(not j.is_object()))
+        {
+            JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(j.type_name())));
+        }
+
+        for (auto it = j.cbegin(); it != j.cend(); ++it)
+        {
+            m_value.object->operator[](it.key()) = it.value();
+        }
+    }
+
+    /*!
+    @brief updates a JSON object from another object, overwriting existing keys
+
+    Inserts all values from from range `[first, last)` and overwrites existing
+    keys.
+
+    @param[in] first begin of the range of elements to insert
+    @param[in] last end of the range of elements to insert
+
+    @throw type_error.312 if called on JSON values other than objects; example:
+    `"cannot use update() with string"`
+    @throw invalid_iterator.202 if iterator @a first or @a last does does not
+    point to an object; example: `"iterators first and last must point to
+    objects"`
+    @throw invalid_iterator.210 if @a first and @a last do not belong to the
+    same JSON value; example: `"iterators do not fit"`
+
+    @complexity O(N*log(size() + N)), where N is the number of elements to
+                insert.
+
+    @liveexample{The example shows how `update()` is used__range.,update}
+
+    @sa https://docs.python.org/3.6/library/stdtypes.html#dict.update
+
+    @since version 3.0.0
+    */
+    void update(const_iterator first, const_iterator last)
+    {
+        // implicitly convert null value to an empty object
+        if (is_null())
+        {
+            m_type = value_t::object;
+            m_value.object = create<object_t>();
+            assert_invariant();
+        }
+
+        if (JSON_UNLIKELY(not is_object()))
+        {
+            JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(type_name())));
+        }
+
+        // check if range iterators belong to the same JSON object
+        if (JSON_UNLIKELY(first.m_object != last.m_object))
+        {
+            JSON_THROW(invalid_iterator::create(210, "iterators do not fit"));
+        }
+
+        // passed iterators must belong to objects
+        if (JSON_UNLIKELY(not first.m_object->is_object()
+                          or not last.m_object->is_object()))
+        {
+            JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects"));
+        }
+
+        for (auto it = first; it != last; ++it)
+        {
+            m_value.object->operator[](it.key()) = it.value();
+        }
+    }
+
+    /*!
+    @brief exchanges the values
+
+    Exchanges the contents of the JSON value with those of @a other. Does not
+    invoke any move, copy, or swap operations on individual elements. All
+    iterators and references remain valid. The past-the-end iterator is
+    invalidated.
+
+    @param[in,out] other JSON value to exchange the contents with
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how JSON values can be swapped with
+    `swap()`.,swap__reference}
+
+    @since version 1.0.0
+    */
+    void swap(reference other) noexcept (
+        std::is_nothrow_move_constructible<value_t>::value and
+        std::is_nothrow_move_assignable<value_t>::value and
+        std::is_nothrow_move_constructible<json_value>::value and
+        std::is_nothrow_move_assignable<json_value>::value
+    )
+    {
+        std::swap(m_type, other.m_type);
+        std::swap(m_value, other.m_value);
+        assert_invariant();
+    }
+
+    /*!
+    @brief exchanges the values
+
+    Exchanges the contents of a JSON array with those of @a other. Does not
+    invoke any move, copy, or swap operations on individual elements. All
+    iterators and references remain valid. The past-the-end iterator is
+    invalidated.
+
+    @param[in,out] other array to exchange the contents with
+
+    @throw type_error.310 when JSON value is not an array; example: `"cannot
+    use swap() with string"`
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how arrays can be swapped with
+    `swap()`.,swap__array_t}
+
+    @since version 1.0.0
+    */
+    void swap(array_t& other)
+    {
+        // swap only works for arrays
+        if (JSON_LIKELY(is_array()))
+        {
+            std::swap(*(m_value.array), other);
+        }
+        else
+        {
+            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name())));
+        }
+    }
+
+    /*!
+    @brief exchanges the values
+
+    Exchanges the contents of a JSON object with those of @a other. Does not
+    invoke any move, copy, or swap operations on individual elements. All
+    iterators and references remain valid. The past-the-end iterator is
+    invalidated.
+
+    @param[in,out] other object to exchange the contents with
+
+    @throw type_error.310 when JSON value is not an object; example:
+    `"cannot use swap() with string"`
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how objects can be swapped with
+    `swap()`.,swap__object_t}
+
+    @since version 1.0.0
+    */
+    void swap(object_t& other)
+    {
+        // swap only works for objects
+        if (JSON_LIKELY(is_object()))
+        {
+            std::swap(*(m_value.object), other);
+        }
+        else
+        {
+            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name())));
+        }
+    }
+
+    /*!
+    @brief exchanges the values
+
+    Exchanges the contents of a JSON string with those of @a other. Does not
+    invoke any move, copy, or swap operations on individual elements. All
+    iterators and references remain valid. The past-the-end iterator is
+    invalidated.
+
+    @param[in,out] other string to exchange the contents with
+
+    @throw type_error.310 when JSON value is not a string; example: `"cannot
+    use swap() with boolean"`
+
+    @complexity Constant.
+
+    @liveexample{The example below shows how strings can be swapped with
+    `swap()`.,swap__string_t}
+
+    @since version 1.0.0
+    */
+    void swap(string_t& other)
+    {
+        // swap only works for strings
+        if (JSON_LIKELY(is_string()))
+        {
+            std::swap(*(m_value.string), other);
+        }
+        else
+        {
+            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name())));
+        }
+    }
+
+    /// @}
+
+  public:
+    //////////////////////////////////////////
+    // lexicographical comparison operators //
+    //////////////////////////////////////////
+
+    /// @name lexicographical comparison operators
+    /// @{
+
+    /*!
+    @brief comparison: equal
+
+    Compares two JSON values for equality according to the following rules:
+    - Two JSON values are equal if (1) they are from the same type and (2)
+      their stored values are the same according to their respective
+      `operator==`.
+    - Integer and floating-point numbers are automatically converted before
+      comparison. Note than two NaN values are always treated as unequal.
+    - Two JSON null values are equal.
+
+    @note Floating-point inside JSON values numbers are compared with
+    `json::number_float_t::operator==` which is `double::operator==` by
+    default. To compare floating-point while respecting an epsilon, an alternative
+    [comparison function](https://github.com/mariokonrad/marnav/blob/master/src/marnav/math/floatingpoint.hpp#L34-#L39)
+    could be used, for instance
+    @code {.cpp}
+    template<typename T, typename = typename std::enable_if<std::is_floating_point<T>::value, T>::type>
+    inline bool is_same(T a, T b, T epsilon = std::numeric_limits<T>::epsilon()) noexcept
+    {
+        return std::abs(a - b) <= epsilon;
+    }
+    @endcode
+
+    @note NaN values never compare equal to themselves or to other NaN values.
+
+    @param[in] lhs  first JSON value to consider
+    @param[in] rhs  second JSON value to consider
+    @return whether the values @a lhs and @a rhs are equal
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @complexity Linear.
+
+    @liveexample{The example demonstrates comparing several JSON
+    types.,operator__equal}
+
+    @since version 1.0.0
+    */
+    friend bool operator==(const_reference lhs, const_reference rhs) noexcept
+    {
+        const auto lhs_type = lhs.type();
+        const auto rhs_type = rhs.type();
+
+        if (lhs_type == rhs_type)
+        {
+            switch (lhs_type)
+            {
+                case value_t::array:
+                    return (*lhs.m_value.array == *rhs.m_value.array);
+
+                case value_t::object:
+                    return (*lhs.m_value.object == *rhs.m_value.object);
+
+                case value_t::null:
+                    return true;
+
+                case value_t::string:
+                    return (*lhs.m_value.string == *rhs.m_value.string);
+
+                case value_t::boolean:
+                    return (lhs.m_value.boolean == rhs.m_value.boolean);
+
+                case value_t::number_integer:
+                    return (lhs.m_value.number_integer == rhs.m_value.number_integer);
+
+                case value_t::number_unsigned:
+                    return (lhs.m_value.number_unsigned == rhs.m_value.number_unsigned);
+
+                case value_t::number_float:
+                    return (lhs.m_value.number_float == rhs.m_value.number_float);
+
+                default:
+                    return false;
+            }
+        }
+        else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float)
+        {
+            return (static_cast<number_float_t>(lhs.m_value.number_integer) == rhs.m_value.number_float);
+        }
+        else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer)
+        {
+            return (lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_integer));
+        }
+        else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float)
+        {
+            return (static_cast<number_float_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_float);
+        }
+        else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned)
+        {
+            return (lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_unsigned));
+        }
+        else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer)
+        {
+            return (static_cast<number_integer_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_integer);
+        }
+        else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned)
+        {
+            return (lhs.m_value.number_integer == static_cast<number_integer_t>(rhs.m_value.number_unsigned));
+        }
+
+        return false;
+    }
+
+    /*!
+    @brief comparison: equal
+    @copydoc operator==(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator==(const_reference lhs, const ScalarType rhs) noexcept
+    {
+        return (lhs == basic_json(rhs));
+    }
+
+    /*!
+    @brief comparison: equal
+    @copydoc operator==(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator==(const ScalarType lhs, const_reference rhs) noexcept
+    {
+        return (basic_json(lhs) == rhs);
+    }
+
+    /*!
+    @brief comparison: not equal
+
+    Compares two JSON values for inequality by calculating `not (lhs == rhs)`.
+
+    @param[in] lhs  first JSON value to consider
+    @param[in] rhs  second JSON value to consider
+    @return whether the values @a lhs and @a rhs are not equal
+
+    @complexity Linear.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @liveexample{The example demonstrates comparing several JSON
+    types.,operator__notequal}
+
+    @since version 1.0.0
+    */
+    friend bool operator!=(const_reference lhs, const_reference rhs) noexcept
+    {
+        return not (lhs == rhs);
+    }
+
+    /*!
+    @brief comparison: not equal
+    @copydoc operator!=(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator!=(const_reference lhs, const ScalarType rhs) noexcept
+    {
+        return (lhs != basic_json(rhs));
+    }
+
+    /*!
+    @brief comparison: not equal
+    @copydoc operator!=(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator!=(const ScalarType lhs, const_reference rhs) noexcept
+    {
+        return (basic_json(lhs) != rhs);
+    }
+
+    /*!
+    @brief comparison: less than
+
+    Compares whether one JSON value @a lhs is less than another JSON value @a
+    rhs according to the following rules:
+    - If @a lhs and @a rhs have the same type, the values are compared using
+      the default `<` operator.
+    - Integer and floating-point numbers are automatically converted before
+      comparison
+    - In case @a lhs and @a rhs have different types, the values are ignored
+      and the order of the types is considered, see
+      @ref operator<(const value_t, const value_t).
+
+    @param[in] lhs  first JSON value to consider
+    @param[in] rhs  second JSON value to consider
+    @return whether @a lhs is less than @a rhs
+
+    @complexity Linear.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @liveexample{The example demonstrates comparing several JSON
+    types.,operator__less}
+
+    @since version 1.0.0
+    */
+    friend bool operator<(const_reference lhs, const_reference rhs) noexcept
+    {
+        const auto lhs_type = lhs.type();
+        const auto rhs_type = rhs.type();
+
+        if (lhs_type == rhs_type)
+        {
+            switch (lhs_type)
+            {
+                case value_t::array:
+                    return (*lhs.m_value.array) < (*rhs.m_value.array);
+
+                case value_t::object:
+                    return *lhs.m_value.object < *rhs.m_value.object;
+
+                case value_t::null:
+                    return false;
+
+                case value_t::string:
+                    return *lhs.m_value.string < *rhs.m_value.string;
+
+                case value_t::boolean:
+                    return lhs.m_value.boolean < rhs.m_value.boolean;
+
+                case value_t::number_integer:
+                    return lhs.m_value.number_integer < rhs.m_value.number_integer;
+
+                case value_t::number_unsigned:
+                    return lhs.m_value.number_unsigned < rhs.m_value.number_unsigned;
+
+                case value_t::number_float:
+                    return lhs.m_value.number_float < rhs.m_value.number_float;
+
+                default:
+                    return false;
+            }
+        }
+        else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float)
+        {
+            return static_cast<number_float_t>(lhs.m_value.number_integer) < rhs.m_value.number_float;
+        }
+        else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer)
+        {
+            return lhs.m_value.number_float < static_cast<number_float_t>(rhs.m_value.number_integer);
+        }
+        else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float)
+        {
+            return static_cast<number_float_t>(lhs.m_value.number_unsigned) < rhs.m_value.number_float;
+        }
+        else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned)
+        {
+            return lhs.m_value.number_float < static_cast<number_float_t>(rhs.m_value.number_unsigned);
+        }
+        else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned)
+        {
+            return lhs.m_value.number_integer < static_cast<number_integer_t>(rhs.m_value.number_unsigned);
+        }
+        else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer)
+        {
+            return static_cast<number_integer_t>(lhs.m_value.number_unsigned) < rhs.m_value.number_integer;
+        }
+
+        // We only reach this line if we cannot compare values. In that case,
+        // we compare types. Note we have to call the operator explicitly,
+        // because MSVC has problems otherwise.
+        return operator<(lhs_type, rhs_type);
+    }
+
+    /*!
+    @brief comparison: less than
+    @copydoc operator<(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator<(const_reference lhs, const ScalarType rhs) noexcept
+    {
+        return (lhs < basic_json(rhs));
+    }
+
+    /*!
+    @brief comparison: less than
+    @copydoc operator<(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator<(const ScalarType lhs, const_reference rhs) noexcept
+    {
+        return (basic_json(lhs) < rhs);
+    }
+
+    /*!
+    @brief comparison: less than or equal
+
+    Compares whether one JSON value @a lhs is less than or equal to another
+    JSON value by calculating `not (rhs < lhs)`.
+
+    @param[in] lhs  first JSON value to consider
+    @param[in] rhs  second JSON value to consider
+    @return whether @a lhs is less than or equal to @a rhs
+
+    @complexity Linear.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @liveexample{The example demonstrates comparing several JSON
+    types.,operator__greater}
+
+    @since version 1.0.0
+    */
+    friend bool operator<=(const_reference lhs, const_reference rhs) noexcept
+    {
+        return not (rhs < lhs);
+    }
+
+    /*!
+    @brief comparison: less than or equal
+    @copydoc operator<=(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator<=(const_reference lhs, const ScalarType rhs) noexcept
+    {
+        return (lhs <= basic_json(rhs));
+    }
+
+    /*!
+    @brief comparison: less than or equal
+    @copydoc operator<=(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator<=(const ScalarType lhs, const_reference rhs) noexcept
+    {
+        return (basic_json(lhs) <= rhs);
+    }
+
+    /*!
+    @brief comparison: greater than
+
+    Compares whether one JSON value @a lhs is greater than another
+    JSON value by calculating `not (lhs <= rhs)`.
+
+    @param[in] lhs  first JSON value to consider
+    @param[in] rhs  second JSON value to consider
+    @return whether @a lhs is greater than to @a rhs
+
+    @complexity Linear.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @liveexample{The example demonstrates comparing several JSON
+    types.,operator__lessequal}
+
+    @since version 1.0.0
+    */
+    friend bool operator>(const_reference lhs, const_reference rhs) noexcept
+    {
+        return not (lhs <= rhs);
+    }
+
+    /*!
+    @brief comparison: greater than
+    @copydoc operator>(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator>(const_reference lhs, const ScalarType rhs) noexcept
+    {
+        return (lhs > basic_json(rhs));
+    }
+
+    /*!
+    @brief comparison: greater than
+    @copydoc operator>(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator>(const ScalarType lhs, const_reference rhs) noexcept
+    {
+        return (basic_json(lhs) > rhs);
+    }
+
+    /*!
+    @brief comparison: greater than or equal
+
+    Compares whether one JSON value @a lhs is greater than or equal to another
+    JSON value by calculating `not (lhs < rhs)`.
+
+    @param[in] lhs  first JSON value to consider
+    @param[in] rhs  second JSON value to consider
+    @return whether @a lhs is greater than or equal to @a rhs
+
+    @complexity Linear.
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @liveexample{The example demonstrates comparing several JSON
+    types.,operator__greaterequal}
+
+    @since version 1.0.0
+    */
+    friend bool operator>=(const_reference lhs, const_reference rhs) noexcept
+    {
+        return not (lhs < rhs);
+    }
+
+    /*!
+    @brief comparison: greater than or equal
+    @copydoc operator>=(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator>=(const_reference lhs, const ScalarType rhs) noexcept
+    {
+        return (lhs >= basic_json(rhs));
+    }
+
+    /*!
+    @brief comparison: greater than or equal
+    @copydoc operator>=(const_reference, const_reference)
+    */
+    template<typename ScalarType, typename std::enable_if<
+                 std::is_scalar<ScalarType>::value, int>::type = 0>
+    friend bool operator>=(const ScalarType lhs, const_reference rhs) noexcept
+    {
+        return (basic_json(lhs) >= rhs);
+    }
+
+    /// @}
+
+    ///////////////////
+    // serialization //
+    ///////////////////
+
+    /// @name serialization
+    /// @{
+
+    /*!
+    @brief serialize to stream
+
+    Serialize the given JSON value @a j to the output stream @a o. The JSON
+    value will be serialized using the @ref dump member function.
+
+    - The indentation of the output can be controlled with the member variable
+      `width` of the output stream @a o. For instance, using the manipulator
+      `std::setw(4)` on @a o sets the indentation level to `4` and the
+      serialization result is the same as calling `dump(4)`.
+
+    - The indentation character can be controlled with the member variable
+      `fill` of the output stream @a o. For instance, the manipulator
+      `std::setfill('\\t')` sets indentation to use a tab character rather than
+      the default space character.
+
+    @param[in,out] o  stream to serialize to
+    @param[in] j  JSON value to serialize
+
+    @return the stream @a o
+
+    @throw type_error.316 if a string stored inside the JSON value is not
+                          UTF-8 encoded
+
+    @complexity Linear.
+
+    @liveexample{The example below shows the serialization with different
+    parameters to `width` to adjust the indentation level.,operator_serialize}
+
+    @since version 1.0.0; indentation character added in version 3.0.0
+    */
+    friend std::ostream& operator<<(std::ostream& o, const basic_json& j)
+    {
+        // read width member and use it as indentation parameter if nonzero
+        const bool pretty_print = (o.width() > 0);
+        const auto indentation = (pretty_print ? o.width() : 0);
+
+        // reset width to 0 for subsequent calls to this stream
+        o.width(0);
+
+        // do the actual serialization
+        serializer s(detail::output_adapter<char>(o), o.fill());
+        s.dump(j, pretty_print, false, static_cast<unsigned int>(indentation));
+        return o;
+    }
+
+    /*!
+    @brief serialize to stream
+    @deprecated This stream operator is deprecated and will be removed in
+                future 4.0.0 of the library. Please use
+                @ref operator<<(std::ostream&, const basic_json&)
+                instead; that is, replace calls like `j >> o;` with `o << j;`.
+    @since version 1.0.0; deprecated since version 3.0.0
+    */
+    JSON_DEPRECATED
+    friend std::ostream& operator>>(const basic_json& j, std::ostream& o)
+    {
+        return o << j;
+    }
+
+    /// @}
+
+
+    /////////////////////
+    // deserialization //
+    /////////////////////
+
+    /// @name deserialization
+    /// @{
+
+    /*!
+    @brief deserialize from a compatible input
+
+    This function reads from a compatible input. Examples are:
+    - an array of 1-byte values
+    - strings with character/literal type with size of 1 byte
+    - input streams
+    - container with contiguous storage of 1-byte values. Compatible container
+      types include `std::vector`, `std::string`, `std::array`,
+      `std::valarray`, and `std::initializer_list`. Furthermore, C-style
+      arrays can be used with `std::begin()`/`std::end()`. User-defined
+      containers can be used as long as they implement random-access iterators
+      and a contiguous storage.
+
+    @pre Each element of the container has a size of 1 byte. Violating this
+    precondition yields undefined behavior. **This precondition is enforced
+    with a static assertion.**
+
+    @pre The container storage is contiguous. Violating this precondition
+    yields undefined behavior. **This precondition is enforced with an
+    assertion.**
+    @pre Each element of the container has a size of 1 byte. Violating this
+    precondition yields undefined behavior. **This precondition is enforced
+    with a static assertion.**
+
+    @warning There is no way to enforce all preconditions at compile-time. If
+             the function is called with a noncompliant container and with
+             assertions switched off, the behavior is undefined and will most
+             likely yield segmentation violation.
+
+    @param[in] i  input to read from
+    @param[in] cb  a parser callback function of type @ref parser_callback_t
+    which is used to control the deserialization by filtering unwanted values
+    (optional)
+    @param[in] allow_exceptions  whether to throw exceptions in case of a
+    parse error (optional, true by default)
+
+    @return result of the deserialization
+
+    @throw parse_error.101 if a parse error occurs; example: `""unexpected end
+    of input; expected string literal""`
+    @throw parse_error.102 if to_unicode fails or surrogate error
+    @throw parse_error.103 if to_unicode fails
+
+    @complexity Linear in the length of the input. The parser is a predictive
+    LL(1) parser. The complexity can be higher if the parser callback function
+    @a cb has a super-linear complexity.
+
+    @note A UTF-8 byte order mark is silently ignored.
+
+    @liveexample{The example below demonstrates the `parse()` function reading
+    from an array.,parse__array__parser_callback_t}
+
+    @liveexample{The example below demonstrates the `parse()` function with
+    and without callback function.,parse__string__parser_callback_t}
+
+    @liveexample{The example below demonstrates the `parse()` function with
+    and without callback function.,parse__istream__parser_callback_t}
+
+    @liveexample{The example below demonstrates the `parse()` function reading
+    from a contiguous container.,parse__contiguouscontainer__parser_callback_t}
+
+    @since version 2.0.3 (contiguous containers)
+    */
+    static basic_json parse(detail::input_adapter&& i,
+                            const parser_callback_t cb = nullptr,
+                            const bool allow_exceptions = true)
+    {
+        basic_json result;
+        parser(i, cb, allow_exceptions).parse(true, result);
+        return result;
+    }
+
+    static bool accept(detail::input_adapter&& i)
+    {
+        return parser(i).accept(true);
+    }
+
+    /*!
+    @brief generate SAX events
+
+    The SAX event lister must follow the interface of @ref json_sax.
+
+    This function reads from a compatible input. Examples are:
+    - an array of 1-byte values
+    - strings with character/literal type with size of 1 byte
+    - input streams
+    - container with contiguous storage of 1-byte values. Compatible container
+      types include `std::vector`, `std::string`, `std::array`,
+      `std::valarray`, and `std::initializer_list`. Furthermore, C-style
+      arrays can be used with `std::begin()`/`std::end()`. User-defined
+      containers can be used as long as they implement random-access iterators
+      and a contiguous storage.
+
+    @pre Each element of the container has a size of 1 byte. Violating this
+    precondition yields undefined behavior. **This precondition is enforced
+    with a static assertion.**
+
+    @pre The container storage is contiguous. Violating this precondition
+    yields undefined behavior. **This precondition is enforced with an
+    assertion.**
+    @pre Each element of the container has a size of 1 byte. Violating this
+    precondition yields undefined behavior. **This precondition is enforced
+    with a static assertion.**
+
+    @warning There is no way to enforce all preconditions at compile-time. If
+             the function is called with a noncompliant container and with
+             assertions switched off, the behavior is undefined and will most
+             likely yield segmentation violation.
+
+    @param[in] i  input to read from
+    @param[in,out] sax  SAX event listener
+    @param[in] format  the format to parse (JSON, CBOR, MessagePack, or UBJSON)
+    @param[in] strict  whether the input has to be consumed completely
+
+    @return return value of the last processed SAX event
+
+    @throw parse_error.101 if a parse error occurs; example: `""unexpected end
+    of input; expected string literal""`
+    @throw parse_error.102 if to_unicode fails or surrogate error
+    @throw parse_error.103 if to_unicode fails
+
+    @complexity Linear in the length of the input. The parser is a predictive
+    LL(1) parser. The complexity can be higher if the SAX consumer @a sax has
+    a super-linear complexity.
+
+    @note A UTF-8 byte order mark is silently ignored.
+
+    @liveexample{The example below demonstrates the `sax_parse()` function
+    reading from string and processing the events with a user-defined SAX
+    event consumer.,sax_parse}
+
+    @since version 3.2.0
+    */
+    template <typename SAX>
+    static bool sax_parse(detail::input_adapter&& i, SAX* sax,
+                          input_format_t format = input_format_t::json,
+                          const bool strict = true)
+    {
+        assert(sax);
+        switch (format)
+        {
+            case input_format_t::json:
+                return parser(std::move(i)).sax_parse(sax, strict);
+            default:
+                return detail::binary_reader<basic_json, SAX>(std::move(i)).sax_parse(format, sax, strict);
+        }
+    }
+
+    /*!
+    @brief deserialize from an iterator range with contiguous storage
+
+    This function reads from an iterator range of a container with contiguous
+    storage of 1-byte values. Compatible container types include
+    `std::vector`, `std::string`, `std::array`, `std::valarray`, and
+    `std::initializer_list`. Furthermore, C-style arrays can be used with
+    `std::begin()`/`std::end()`. User-defined containers can be used as long
+    as they implement random-access iterators and a contiguous storage.
+
+    @pre The iterator range is contiguous. Violating this precondition yields
+    undefined behavior. **This precondition is enforced with an assertion.**
+    @pre Each element in the range has a size of 1 byte. Violating this
+    precondition yields undefined behavior. **This precondition is enforced
+    with a static assertion.**
+
+    @warning There is no way to enforce all preconditions at compile-time. If
+             the function is called with noncompliant iterators and with
+             assertions switched off, the behavior is undefined and will most
+             likely yield segmentation violation.
+
+    @tparam IteratorType iterator of container with contiguous storage
+    @param[in] first  begin of the range to parse (included)
+    @param[in] last  end of the range to parse (excluded)
+    @param[in] cb  a parser callback function of type @ref parser_callback_t
+    which is used to control the deserialization by filtering unwanted values
+    (optional)
+    @param[in] allow_exceptions  whether to throw exceptions in case of a
+    parse error (optional, true by default)
+
+    @return result of the deserialization
+
+    @throw parse_error.101 in case of an unexpected token
+    @throw parse_error.102 if to_unicode fails or surrogate error
+    @throw parse_error.103 if to_unicode fails
+
+    @complexity Linear in the length of the input. The parser is a predictive
+    LL(1) parser. The complexity can be higher if the parser callback function
+    @a cb has a super-linear complexity.
+
+    @note A UTF-8 byte order mark is silently ignored.
+
+    @liveexample{The example below demonstrates the `parse()` function reading
+    from an iterator range.,parse__iteratortype__parser_callback_t}
+
+    @since version 2.0.3
+    */
+    template<class IteratorType, typename std::enable_if<
+                 std::is_base_of<
+                     std::random_access_iterator_tag,
+                     typename std::iterator_traits<IteratorType>::iterator_category>::value, int>::type = 0>
+    static basic_json parse(IteratorType first, IteratorType last,
+                            const parser_callback_t cb = nullptr,
+                            const bool allow_exceptions = true)
+    {
+        basic_json result;
+        parser(detail::input_adapter(first, last), cb, allow_exceptions).parse(true, result);
+        return result;
+    }
+
+    template<class IteratorType, typename std::enable_if<
+                 std::is_base_of<
+                     std::random_access_iterator_tag,
+                     typename std::iterator_traits<IteratorType>::iterator_category>::value, int>::type = 0>
+    static bool accept(IteratorType first, IteratorType last)
+    {
+        return parser(detail::input_adapter(first, last)).accept(true);
+    }
+
+    template<class IteratorType, class SAX, typename std::enable_if<
+                 std::is_base_of<
+                     std::random_access_iterator_tag,
+                     typename std::iterator_traits<IteratorType>::iterator_category>::value, int>::type = 0>
+    static bool sax_parse(IteratorType first, IteratorType last, SAX* sax)
+    {
+        return parser(detail::input_adapter(first, last)).sax_parse(sax);
+    }
+
+    /*!
+    @brief deserialize from stream
+    @deprecated This stream operator is deprecated and will be removed in
+                version 4.0.0 of the library. Please use
+                @ref operator>>(std::istream&, basic_json&)
+                instead; that is, replace calls like `j << i;` with `i >> j;`.
+    @since version 1.0.0; deprecated since version 3.0.0
+    */
+    JSON_DEPRECATED
+    friend std::istream& operator<<(basic_json& j, std::istream& i)
+    {
+        return operator>>(i, j);
+    }
+
+    /*!
+    @brief deserialize from stream
+
+    Deserializes an input stream to a JSON value.
+
+    @param[in,out] i  input stream to read a serialized JSON value from
+    @param[in,out] j  JSON value to write the deserialized input to
+
+    @throw parse_error.101 in case of an unexpected token
+    @throw parse_error.102 if to_unicode fails or surrogate error
+    @throw parse_error.103 if to_unicode fails
+
+    @complexity Linear in the length of the input. The parser is a predictive
+    LL(1) parser.
+
+    @note A UTF-8 byte order mark is silently ignored.
+
+    @liveexample{The example below shows how a JSON value is constructed by
+    reading a serialization from a stream.,operator_deserialize}
+
+    @sa parse(std::istream&, const parser_callback_t) for a variant with a
+    parser callback function to filter values while parsing
+
+    @since version 1.0.0
+    */
+    friend std::istream& operator>>(std::istream& i, basic_json& j)
+    {
+        parser(detail::input_adapter(i)).parse(false, j);
+        return i;
+    }
+
+    /// @}
+
+    ///////////////////////////
+    // convenience functions //
+    ///////////////////////////
+
+    /*!
+    @brief return the type as string
+
+    Returns the type name as string to be used in error messages - usually to
+    indicate that a function was called on a wrong JSON type.
+
+    @return a string representation of a the @a m_type member:
+            Value type  | return value
+            ----------- | -------------
+            null        | `"null"`
+            boolean     | `"boolean"`
+            string      | `"string"`
+            number      | `"number"` (for all number types)
+            object      | `"object"`
+            array       | `"array"`
+            discarded   | `"discarded"`
+
+    @exceptionsafety No-throw guarantee: this function never throws exceptions.
+
+    @complexity Constant.
+
+    @liveexample{The following code exemplifies `type_name()` for all JSON
+    types.,type_name}
+
+    @sa @ref type() -- return the type of the JSON value
+    @sa @ref operator value_t() -- return the type of the JSON value (implicit)
+
+    @since version 1.0.0, public since 2.1.0, `const char*` and `noexcept`
+    since 3.0.0
+    */
+    const char* type_name() const noexcept
+    {
+        {
+            switch (m_type)
+            {
+                case value_t::null:
+                    return "null";
+                case value_t::object:
+                    return "object";
+                case value_t::array:
+                    return "array";
+                case value_t::string:
+                    return "string";
+                case value_t::boolean:
+                    return "boolean";
+                case value_t::discarded:
+                    return "discarded";
+                default:
+                    return "number";
+            }
+        }
+    }
+
+
+  private:
+    //////////////////////
+    // member variables //
+    //////////////////////
+
+    /// the type of the current element
+    value_t m_type = value_t::null;
+
+    /// the value of the current element
+    json_value m_value = {};
+
+    //////////////////////////////////////////
+    // binary serialization/deserialization //
+    //////////////////////////////////////////
+
+    /// @name binary serialization/deserialization support
+    /// @{
+
+  public:
+    /*!
+    @brief create a CBOR serialization of a given JSON value
+
+    Serializes a given JSON value @a j to a byte vector using the CBOR (Concise
+    Binary Object Representation) serialization format. CBOR is a binary
+    serialization format which aims to be more compact than JSON itself, yet
+    more efficient to parse.
+
+    The library uses the following mapping from JSON values types to
+    CBOR types according to the CBOR specification (RFC 7049):
+
+    JSON value type | value/range                                | CBOR type                          | first byte
+    --------------- | ------------------------------------------ | ---------------------------------- | ---------------
+    null            | `null`                                     | Null                               | 0xF6
+    boolean         | `true`                                     | True                               | 0xF5
+    boolean         | `false`                                    | False                              | 0xF4
+    number_integer  | -9223372036854775808..-2147483649          | Negative integer (8 bytes follow)  | 0x3B
+    number_integer  | -2147483648..-32769                        | Negative integer (4 bytes follow)  | 0x3A
+    number_integer  | -32768..-129                               | Negative integer (2 bytes follow)  | 0x39
+    number_integer  | -128..-25                                  | Negative integer (1 byte follow)   | 0x38
+    number_integer  | -24..-1                                    | Negative integer                   | 0x20..0x37
+    number_integer  | 0..23                                      | Integer                            | 0x00..0x17
+    number_integer  | 24..255                                    | Unsigned integer (1 byte follow)   | 0x18
+    number_integer  | 256..65535                                 | Unsigned integer (2 bytes follow)  | 0x19
+    number_integer  | 65536..4294967295                          | Unsigned integer (4 bytes follow)  | 0x1A
+    number_integer  | 4294967296..18446744073709551615           | Unsigned integer (8 bytes follow)  | 0x1B
+    number_unsigned | 0..23                                      | Integer                            | 0x00..0x17
+    number_unsigned | 24..255                                    | Unsigned integer (1 byte follow)   | 0x18
+    number_unsigned | 256..65535                                 | Unsigned integer (2 bytes follow)  | 0x19
+    number_unsigned | 65536..4294967295                          | Unsigned integer (4 bytes follow)  | 0x1A
+    number_unsigned | 4294967296..18446744073709551615           | Unsigned integer (8 bytes follow)  | 0x1B
+    number_float    | *any value*                                | Double-Precision Float             | 0xFB
+    string          | *length*: 0..23                            | UTF-8 string                       | 0x60..0x77
+    string          | *length*: 23..255                          | UTF-8 string (1 byte follow)       | 0x78
+    string          | *length*: 256..65535                       | UTF-8 string (2 bytes follow)      | 0x79
+    string          | *length*: 65536..4294967295                | UTF-8 string (4 bytes follow)      | 0x7A
+    string          | *length*: 4294967296..18446744073709551615 | UTF-8 string (8 bytes follow)      | 0x7B
+    array           | *size*: 0..23                              | array                              | 0x80..0x97
+    array           | *size*: 23..255                            | array (1 byte follow)              | 0x98
+    array           | *size*: 256..65535                         | array (2 bytes follow)             | 0x99
+    array           | *size*: 65536..4294967295                  | array (4 bytes follow)             | 0x9A
+    array           | *size*: 4294967296..18446744073709551615   | array (8 bytes follow)             | 0x9B
+    object          | *size*: 0..23                              | map                                | 0xA0..0xB7
+    object          | *size*: 23..255                            | map (1 byte follow)                | 0xB8
+    object          | *size*: 256..65535                         | map (2 bytes follow)               | 0xB9
+    object          | *size*: 65536..4294967295                  | map (4 bytes follow)               | 0xBA
+    object          | *size*: 4294967296..18446744073709551615   | map (8 bytes follow)               | 0xBB
+
+    @note The mapping is **complete** in the sense that any JSON value type
+          can be converted to a CBOR value.
+
+    @note If NaN or Infinity are stored inside a JSON number, they are
+          serialized properly. This behavior differs from the @ref dump()
+          function which serializes NaN or Infinity to `null`.
+
+    @note The following CBOR types are not used in the conversion:
+          - byte strings (0x40..0x5F)
+          - UTF-8 strings terminated by "break" (0x7F)
+          - arrays terminated by "break" (0x9F)
+          - maps terminated by "break" (0xBF)
+          - date/time (0xC0..0xC1)
+          - bignum (0xC2..0xC3)
+          - decimal fraction (0xC4)
+          - bigfloat (0xC5)
+          - tagged items (0xC6..0xD4, 0xD8..0xDB)
+          - expected conversions (0xD5..0xD7)
+          - simple values (0xE0..0xF3, 0xF8)
+          - undefined (0xF7)
+          - half and single-precision floats (0xF9-0xFA)
+          - break (0xFF)
+
+    @param[in] j  JSON value to serialize
+    @return MessagePack serialization as byte vector
+
+    @complexity Linear in the size of the JSON value @a j.
+
+    @liveexample{The example shows the serialization of a JSON value to a byte
+    vector in CBOR format.,to_cbor}
+
+    @sa http://cbor.io
+    @sa @ref from_cbor(detail::input_adapter&&, const bool, const bool) for the
+        analogous deserialization
+    @sa @ref to_msgpack(const basic_json&) for the related MessagePack format
+    @sa @ref to_ubjson(const basic_json&, const bool, const bool) for the
+             related UBJSON format
+
+    @since version 2.0.9
+    */
+    static std::vector<uint8_t> to_cbor(const basic_json& j)
+    {
+        std::vector<uint8_t> result;
+        to_cbor(j, result);
+        return result;
+    }
+
+    static void to_cbor(const basic_json& j, detail::output_adapter<uint8_t> o)
+    {
+        binary_writer<uint8_t>(o).write_cbor(j);
+    }
+
+    static void to_cbor(const basic_json& j, detail::output_adapter<char> o)
+    {
+        binary_writer<char>(o).write_cbor(j);
+    }
+
+    /*!
+    @brief create a MessagePack serialization of a given JSON value
+
+    Serializes a given JSON value @a j to a byte vector using the MessagePack
+    serialization format. MessagePack is a binary serialization format which
+    aims to be more compact than JSON itself, yet more efficient to parse.
+
+    The library uses the following mapping from JSON values types to
+    MessagePack types according to the MessagePack specification:
+
+    JSON value type | value/range                       | MessagePack type | first byte
+    --------------- | --------------------------------- | ---------------- | ----------
+    null            | `null`                            | nil              | 0xC0
+    boolean         | `true`                            | true             | 0xC3
+    boolean         | `false`                           | false            | 0xC2
+    number_integer  | -9223372036854775808..-2147483649 | int64            | 0xD3
+    number_integer  | -2147483648..-32769               | int32            | 0xD2
+    number_integer  | -32768..-129                      | int16            | 0xD1
+    number_integer  | -128..-33                         | int8             | 0xD0
+    number_integer  | -32..-1                           | negative fixint  | 0xE0..0xFF
+    number_integer  | 0..127                            | positive fixint  | 0x00..0x7F
+    number_integer  | 128..255                          | uint 8           | 0xCC
+    number_integer  | 256..65535                        | uint 16          | 0xCD
+    number_integer  | 65536..4294967295                 | uint 32          | 0xCE
+    number_integer  | 4294967296..18446744073709551615  | uint 64          | 0xCF
+    number_unsigned | 0..127                            | positive fixint  | 0x00..0x7F
+    number_unsigned | 128..255                          | uint 8           | 0xCC
+    number_unsigned | 256..65535                        | uint 16          | 0xCD
+    number_unsigned | 65536..4294967295                 | uint 32          | 0xCE
+    number_unsigned | 4294967296..18446744073709551615  | uint 64          | 0xCF
+    number_float    | *any value*                       | float 64         | 0xCB
+    string          | *length*: 0..31                   | fixstr           | 0xA0..0xBF
+    string          | *length*: 32..255                 | str 8            | 0xD9
+    string          | *length*: 256..65535              | str 16           | 0xDA
+    string          | *length*: 65536..4294967295       | str 32           | 0xDB
+    array           | *size*: 0..15                     | fixarray         | 0x90..0x9F
+    array           | *size*: 16..65535                 | array 16         | 0xDC
+    array           | *size*: 65536..4294967295         | array 32         | 0xDD
+    object          | *size*: 0..15                     | fix map          | 0x80..0x8F
+    object          | *size*: 16..65535                 | map 16           | 0xDE
+    object          | *size*: 65536..4294967295         | map 32           | 0xDF
+
+    @note The mapping is **complete** in the sense that any JSON value type
+          can be converted to a MessagePack value.
+
+    @note The following values can **not** be converted to a MessagePack value:
+          - strings with more than 4294967295 bytes
+          - arrays with more than 4294967295 elements
+          - objects with more than 4294967295 elements
+
+    @note The following MessagePack types are not used in the conversion:
+          - bin 8 - bin 32 (0xC4..0xC6)
+          - ext 8 - ext 32 (0xC7..0xC9)
+          - float 32 (0xCA)
+          - fixext 1 - fixext 16 (0xD4..0xD8)
+
+    @note Any MessagePack output created @ref to_msgpack can be successfully
+          parsed by @ref from_msgpack.
+
+    @note If NaN or Infinity are stored inside a JSON number, they are
+          serialized properly. This behavior differs from the @ref dump()
+          function which serializes NaN or Infinity to `null`.
+
+    @param[in] j  JSON value to serialize
+    @return MessagePack serialization as byte vector
+
+    @complexity Linear in the size of the JSON value @a j.
+
+    @liveexample{The example shows the serialization of a JSON value to a byte
+    vector in MessagePack format.,to_msgpack}
+
+    @sa http://msgpack.org
+    @sa @ref from_msgpack for the analogous deserialization
+    @sa @ref to_cbor(const basic_json& for the related CBOR format
+    @sa @ref to_ubjson(const basic_json&, const bool, const bool) for the
+             related UBJSON format
+
+    @since version 2.0.9
+    */
+    static std::vector<uint8_t> to_msgpack(const basic_json& j)
+    {
+        std::vector<uint8_t> result;
+        to_msgpack(j, result);
+        return result;
+    }
+
+    static void to_msgpack(const basic_json& j, detail::output_adapter<uint8_t> o)
+    {
+        binary_writer<uint8_t>(o).write_msgpack(j);
+    }
+
+    static void to_msgpack(const basic_json& j, detail::output_adapter<char> o)
+    {
+        binary_writer<char>(o).write_msgpack(j);
+    }
+
+    /*!
+    @brief create a UBJSON serialization of a given JSON value
+
+    Serializes a given JSON value @a j to a byte vector using the UBJSON
+    (Universal Binary JSON) serialization format. UBJSON aims to be more compact
+    than JSON itself, yet more efficient to parse.
+
+    The library uses the following mapping from JSON values types to
+    UBJSON types according to the UBJSON specification:
+
+    JSON value type | value/range                       | UBJSON type | marker
+    --------------- | --------------------------------- | ----------- | ------
+    null            | `null`                            | null        | `Z`
+    boolean         | `true`                            | true        | `T`
+    boolean         | `false`                           | false       | `F`
+    number_integer  | -9223372036854775808..-2147483649 | int64       | `L`
+    number_integer  | -2147483648..-32769               | int32       | `l`
+    number_integer  | -32768..-129                      | int16       | `I`
+    number_integer  | -128..127                         | int8        | `i`
+    number_integer  | 128..255                          | uint8       | `U`
+    number_integer  | 256..32767                        | int16       | `I`
+    number_integer  | 32768..2147483647                 | int32       | `l`
+    number_integer  | 2147483648..9223372036854775807   | int64       | `L`
+    number_unsigned | 0..127                            | int8        | `i`
+    number_unsigned | 128..255                          | uint8       | `U`
+    number_unsigned | 256..32767                        | int16       | `I`
+    number_unsigned | 32768..2147483647                 | int32       | `l`
+    number_unsigned | 2147483648..9223372036854775807   | int64       | `L`
+    number_float    | *any value*                       | float64     | `D`
+    string          | *with shortest length indicator*  | string      | `S`
+    array           | *see notes on optimized format*   | array       | `[`
+    object          | *see notes on optimized format*   | map         | `{`
+
+    @note The mapping is **complete** in the sense that any JSON value type
+          can be converted to a UBJSON value.
+
+    @note The following values can **not** be converted to a UBJSON value:
+          - strings with more than 9223372036854775807 bytes (theoretical)
+          - unsigned integer numbers above 9223372036854775807
+
+    @note The following markers are not used in the conversion:
+          - `Z`: no-op values are not created.
+          - `C`: single-byte strings are serialized with `S` markers.
+
+    @note Any UBJSON output created @ref to_ubjson can be successfully parsed
+          by @ref from_ubjson.
+
+    @note If NaN or Infinity are stored inside a JSON number, they are
+          serialized properly. This behavior differs from the @ref dump()
+          function which serializes NaN or Infinity to `null`.
+
+    @note The optimized formats for containers are supported: Parameter
+          @a use_size adds size information to the beginning of a container and
+          removes the closing marker. Parameter @a use_type further checks
+          whether all elements of a container have the same type and adds the
+          type marker to the beginning of the container. The @a use_type
+          parameter must only be used together with @a use_size = true. Note
+          that @a use_size = true alone may result in larger representations -
+          the benefit of this parameter is that the receiving side is
+          immediately informed on the number of elements of the container.
+
+    @param[in] j  JSON value to serialize
+    @param[in] use_size  whether to add size annotations to container types
+    @param[in] use_type  whether to add type annotations to container types
+                         (must be combined with @a use_size = true)
+    @return UBJSON serialization as byte vector
+
+    @complexity Linear in the size of the JSON value @a j.
+
+    @liveexample{The example shows the serialization of a JSON value to a byte
+    vector in UBJSON format.,to_ubjson}
+
+    @sa http://ubjson.org
+    @sa @ref from_ubjson(detail::input_adapter&&, const bool, const bool) for the
+        analogous deserialization
+    @sa @ref to_cbor(const basic_json& for the related CBOR format
+    @sa @ref to_msgpack(const basic_json&) for the related MessagePack format
+
+    @since version 3.1.0
+    */
+    static std::vector<uint8_t> to_ubjson(const basic_json& j,
+                                          const bool use_size = false,
+                                          const bool use_type = false)
+    {
+        std::vector<uint8_t> result;
+        to_ubjson(j, result, use_size, use_type);
+        return result;
+    }
+
+    static void to_ubjson(const basic_json& j, detail::output_adapter<uint8_t> o,
+                          const bool use_size = false, const bool use_type = false)
+    {
+        binary_writer<uint8_t>(o).write_ubjson(j, use_size, use_type);
+    }
+
+    static void to_ubjson(const basic_json& j, detail::output_adapter<char> o,
+                          const bool use_size = false, const bool use_type = false)
+    {
+        binary_writer<char>(o).write_ubjson(j, use_size, use_type);
+    }
+
+
+    /*!
+    @brief Serializes the given JSON object `j` to BSON and returns a vector
+           containing the corresponding BSON-representation.
+
+    BSON (Binary JSON) is a binary format in which zero or more ordered key/value pairs are
+    stored as a single entity (a so-called document).
+
+    The library uses the following mapping from JSON values types to BSON types:
+
+    JSON value type | value/range                       | BSON type   | marker
+    --------------- | --------------------------------- | ----------- | ------
+    null            | `null`                            | null        | 0x0A
+    boolean         | `true`, `false`                   | boolean     | 0x08
+    number_integer  | -9223372036854775808..-2147483649 | int64       | 0x12
+    number_integer  | -2147483648..2147483647           | int32       | 0x10
+    number_integer  | 2147483648..9223372036854775807   | int64       | 0x12
+    number_unsigned | 0..2147483647                     | int32       | 0x10
+    number_unsigned | 2147483648..9223372036854775807   | int64       | 0x12
+    number_unsigned | 9223372036854775808..18446744073709551615| --   | --
+    number_float    | *any value*                       | double      | 0x01
+    string          | *any value*                       | string      | 0x02
+    array           | *any value*                       | document    | 0x04
+    object          | *any value*                       | document    | 0x03
+
+    @warning The mapping is **incomplete**, since only JSON-objects (and things
+    contained therein) can be serialized to BSON.
+    Also, integers larger than 9223372036854775807 cannot be serialized to BSON,
+    and the keys may not contain U+0000, since they are serialized a
+    zero-terminated c-strings.
+
+    @throw out_of_range.407  if `j.is_number_unsigned() && j.get<std::uint64_t>() > 9223372036854775807`
+    @throw out_of_range.409  if a key in `j` contains a NULL (U+0000)
+    @throw type_error.317    if `!j.is_object()`
+
+    @pre The input `j` is required to be an object: `j.is_object() == true`.
+
+    @note Any BSON output created via @ref to_bson can be successfully parsed
+          by @ref from_bson.
+
+    @param[in] j  JSON value to serialize
+    @return BSON serialization as byte vector
+
+    @complexity Linear in the size of the JSON value @a j.
+
+    @liveexample{The example shows the serialization of a JSON value to a byte
+    vector in BSON format.,to_bson}
+
+    @sa http://bsonspec.org/spec.html
+    @sa @ref from_bson(detail::input_adapter&&, const bool strict) for the
+        analogous deserialization
+    @sa @ref to_ubjson(const basic_json&, const bool, const bool) for the
+             related UBJSON format
+    @sa @ref to_cbor(const basic_json&) for the related CBOR format
+    @sa @ref to_msgpack(const basic_json&) for the related MessagePack format
+    */
+    static std::vector<uint8_t> to_bson(const basic_json& j)
+    {
+        std::vector<uint8_t> result;
+        to_bson(j, result);
+        return result;
+    }
+
+    /*!
+    @brief Serializes the given JSON object `j` to BSON and forwards the
+           corresponding BSON-representation to the given output_adapter `o`.
+    @param j The JSON object to convert to BSON.
+    @param o The output adapter that receives the binary BSON representation.
+    @pre The input `j` shall be an object: `j.is_object() == true`
+    @sa @ref to_bson(const basic_json&)
+    */
+    static void to_bson(const basic_json& j, detail::output_adapter<uint8_t> o)
+    {
+        binary_writer<uint8_t>(o).write_bson(j);
+    }
+
+    /*!
+    @copydoc to_bson(const basic_json&, detail::output_adapter<uint8_t>)
+    */
+    static void to_bson(const basic_json& j, detail::output_adapter<char> o)
+    {
+        binary_writer<char>(o).write_bson(j);
+    }
+
+
+    /*!
+    @brief create a JSON value from an input in CBOR format
+
+    Deserializes a given input @a i to a JSON value using the CBOR (Concise
+    Binary Object Representation) serialization format.
+
+    The library maps CBOR types to JSON value types as follows:
+
+    CBOR type              | JSON value type | first byte
+    ---------------------- | --------------- | ----------
+    Integer                | number_unsigned | 0x00..0x17
+    Unsigned integer       | number_unsigned | 0x18
+    Unsigned integer       | number_unsigned | 0x19
+    Unsigned integer       | number_unsigned | 0x1A
+    Unsigned integer       | number_unsigned | 0x1B
+    Negative integer       | number_integer  | 0x20..0x37
+    Negative integer       | number_integer  | 0x38
+    Negative integer       | number_integer  | 0x39
+    Negative integer       | number_integer  | 0x3A
+    Negative integer       | number_integer  | 0x3B
+    Negative integer       | number_integer  | 0x40..0x57
+    UTF-8 string           | string          | 0x60..0x77
+    UTF-8 string           | string          | 0x78
+    UTF-8 string           | string          | 0x79
+    UTF-8 string           | string          | 0x7A
+    UTF-8 string           | string          | 0x7B
+    UTF-8 string           | string          | 0x7F
+    array                  | array           | 0x80..0x97
+    array                  | array           | 0x98
+    array                  | array           | 0x99
+    array                  | array           | 0x9A
+    array                  | array           | 0x9B
+    array                  | array           | 0x9F
+    map                    | object          | 0xA0..0xB7
+    map                    | object          | 0xB8
+    map                    | object          | 0xB9
+    map                    | object          | 0xBA
+    map                    | object          | 0xBB
+    map                    | object          | 0xBF
+    False                  | `false`         | 0xF4
+    True                   | `true`          | 0xF5
+    Null                   | `null`          | 0xF6
+    Half-Precision Float   | number_float    | 0xF9
+    Single-Precision Float | number_float    | 0xFA
+    Double-Precision Float | number_float    | 0xFB
+
+    @warning The mapping is **incomplete** in the sense that not all CBOR
+             types can be converted to a JSON value. The following CBOR types
+             are not supported and will yield parse errors (parse_error.112):
+             - byte strings (0x40..0x5F)
+             - date/time (0xC0..0xC1)
+             - bignum (0xC2..0xC3)
+             - decimal fraction (0xC4)
+             - bigfloat (0xC5)
+             - tagged items (0xC6..0xD4, 0xD8..0xDB)
+             - expected conversions (0xD5..0xD7)
+             - simple values (0xE0..0xF3, 0xF8)
+             - undefined (0xF7)
+
+    @warning CBOR allows map keys of any type, whereas JSON only allows
+             strings as keys in object values. Therefore, CBOR maps with keys
+             other than UTF-8 strings are rejected (parse_error.113).
+
+    @note Any CBOR output created @ref to_cbor can be successfully parsed by
+          @ref from_cbor.
+
+    @param[in] i  an input in CBOR format convertible to an input adapter
+    @param[in] strict  whether to expect the input to be consumed until EOF
+                       (true by default)
+    @param[in] allow_exceptions  whether to throw exceptions in case of a
+    parse error (optional, true by default)
+
+    @return deserialized JSON value
+
+    @throw parse_error.110 if the given input ends prematurely or the end of
+    file was not reached when @a strict was set to true
+    @throw parse_error.112 if unsupported features from CBOR were
+    used in the given input @a v or if the input is not valid CBOR
+    @throw parse_error.113 if a string was expected as map key, but not found
+
+    @complexity Linear in the size of the input @a i.
+
+    @liveexample{The example shows the deserialization of a byte vector in CBOR
+    format to a JSON value.,from_cbor}
+
+    @sa http://cbor.io
+    @sa @ref to_cbor(const basic_json&) for the analogous serialization
+    @sa @ref from_msgpack(detail::input_adapter&&, const bool, const bool) for the
+        related MessagePack format
+    @sa @ref from_ubjson(detail::input_adapter&&, const bool, const bool) for the
+        related UBJSON format
+
+    @since version 2.0.9; parameter @a start_index since 2.1.1; changed to
+           consume input adapters, removed start_index parameter, and added
+           @a strict parameter since 3.0.0; added @a allow_exceptions parameter
+           since 3.2.0
+    */
+    static basic_json from_cbor(detail::input_adapter&& i,
+                                const bool strict = true,
+                                const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(i)).sax_parse(input_format_t::cbor, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @copydoc from_cbor(detail::input_adapter&&, const bool, const bool)
+    */
+    template<typename A1, typename A2,
+             detail::enable_if_t<std::is_constructible<detail::input_adapter, A1, A2>::value, int> = 0>
+    static basic_json from_cbor(A1 && a1, A2 && a2,
+                                const bool strict = true,
+                                const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(std::forward<A1>(a1), std::forward<A2>(a2))).sax_parse(input_format_t::cbor, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @brief create a JSON value from an input in MessagePack format
+
+    Deserializes a given input @a i to a JSON value using the MessagePack
+    serialization format.
+
+    The library maps MessagePack types to JSON value types as follows:
+
+    MessagePack type | JSON value type | first byte
+    ---------------- | --------------- | ----------
+    positive fixint  | number_unsigned | 0x00..0x7F
+    fixmap           | object          | 0x80..0x8F
+    fixarray         | array           | 0x90..0x9F
+    fixstr           | string          | 0xA0..0xBF
+    nil              | `null`          | 0xC0
+    false            | `false`         | 0xC2
+    true             | `true`          | 0xC3
+    float 32         | number_float    | 0xCA
+    float 64         | number_float    | 0xCB
+    uint 8           | number_unsigned | 0xCC
+    uint 16          | number_unsigned | 0xCD
+    uint 32          | number_unsigned | 0xCE
+    uint 64          | number_unsigned | 0xCF
+    int 8            | number_integer  | 0xD0
+    int 16           | number_integer  | 0xD1
+    int 32           | number_integer  | 0xD2
+    int 64           | number_integer  | 0xD3
+    str 8            | string          | 0xD9
+    str 16           | string          | 0xDA
+    str 32           | string          | 0xDB
+    array 16         | array           | 0xDC
+    array 32         | array           | 0xDD
+    map 16           | object          | 0xDE
+    map 32           | object          | 0xDF
+    negative fixint  | number_integer  | 0xE0-0xFF
+
+    @warning The mapping is **incomplete** in the sense that not all
+             MessagePack types can be converted to a JSON value. The following
+             MessagePack types are not supported and will yield parse errors:
+              - bin 8 - bin 32 (0xC4..0xC6)
+              - ext 8 - ext 32 (0xC7..0xC9)
+              - fixext 1 - fixext 16 (0xD4..0xD8)
+
+    @note Any MessagePack output created @ref to_msgpack can be successfully
+          parsed by @ref from_msgpack.
+
+    @param[in] i  an input in MessagePack format convertible to an input
+                  adapter
+    @param[in] strict  whether to expect the input to be consumed until EOF
+                       (true by default)
+    @param[in] allow_exceptions  whether to throw exceptions in case of a
+    parse error (optional, true by default)
+
+    @return deserialized JSON value
+
+    @throw parse_error.110 if the given input ends prematurely or the end of
+    file was not reached when @a strict was set to true
+    @throw parse_error.112 if unsupported features from MessagePack were
+    used in the given input @a i or if the input is not valid MessagePack
+    @throw parse_error.113 if a string was expected as map key, but not found
+
+    @complexity Linear in the size of the input @a i.
+
+    @liveexample{The example shows the deserialization of a byte vector in
+    MessagePack format to a JSON value.,from_msgpack}
+
+    @sa http://msgpack.org
+    @sa @ref to_msgpack(const basic_json&) for the analogous serialization
+    @sa @ref from_cbor(detail::input_adapter&&, const bool, const bool) for the
+        related CBOR format
+    @sa @ref from_ubjson(detail::input_adapter&&, const bool, const bool) for
+        the related UBJSON format
+    @sa @ref from_bson(detail::input_adapter&&, const bool, const bool) for
+        the related BSON format
+
+    @since version 2.0.9; parameter @a start_index since 2.1.1; changed to
+           consume input adapters, removed start_index parameter, and added
+           @a strict parameter since 3.0.0; added @a allow_exceptions parameter
+           since 3.2.0
+    */
+    static basic_json from_msgpack(detail::input_adapter&& i,
+                                   const bool strict = true,
+                                   const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(i)).sax_parse(input_format_t::msgpack, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @copydoc from_msgpack(detail::input_adapter&&, const bool, const bool)
+    */
+    template<typename A1, typename A2,
+             detail::enable_if_t<std::is_constructible<detail::input_adapter, A1, A2>::value, int> = 0>
+    static basic_json from_msgpack(A1 && a1, A2 && a2,
+                                   const bool strict = true,
+                                   const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(std::forward<A1>(a1), std::forward<A2>(a2))).sax_parse(input_format_t::msgpack, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @brief create a JSON value from an input in UBJSON format
+
+    Deserializes a given input @a i to a JSON value using the UBJSON (Universal
+    Binary JSON) serialization format.
+
+    The library maps UBJSON types to JSON value types as follows:
+
+    UBJSON type | JSON value type                         | marker
+    ----------- | --------------------------------------- | ------
+    no-op       | *no value, next value is read*          | `N`
+    null        | `null`                                  | `Z`
+    false       | `false`                                 | `F`
+    true        | `true`                                  | `T`
+    float32     | number_float                            | `d`
+    float64     | number_float                            | `D`
+    uint8       | number_unsigned                         | `U`
+    int8        | number_integer                          | `i`
+    int16       | number_integer                          | `I`
+    int32       | number_integer                          | `l`
+    int64       | number_integer                          | `L`
+    string      | string                                  | `S`
+    char        | string                                  | `C`
+    array       | array (optimized values are supported)  | `[`
+    object      | object (optimized values are supported) | `{`
+
+    @note The mapping is **complete** in the sense that any UBJSON value can
+          be converted to a JSON value.
+
+    @param[in] i  an input in UBJSON format convertible to an input adapter
+    @param[in] strict  whether to expect the input to be consumed until EOF
+                       (true by default)
+    @param[in] allow_exceptions  whether to throw exceptions in case of a
+    parse error (optional, true by default)
+
+    @return deserialized JSON value
+
+    @throw parse_error.110 if the given input ends prematurely or the end of
+    file was not reached when @a strict was set to true
+    @throw parse_error.112 if a parse error occurs
+    @throw parse_error.113 if a string could not be parsed successfully
+
+    @complexity Linear in the size of the input @a i.
+
+    @liveexample{The example shows the deserialization of a byte vector in
+    UBJSON format to a JSON value.,from_ubjson}
+
+    @sa http://ubjson.org
+    @sa @ref to_ubjson(const basic_json&, const bool, const bool) for the
+             analogous serialization
+    @sa @ref from_cbor(detail::input_adapter&&, const bool, const bool) for the
+        related CBOR format
+    @sa @ref from_msgpack(detail::input_adapter&&, const bool, const bool) for
+        the related MessagePack format
+    @sa @ref from_bson(detail::input_adapter&&, const bool, const bool) for
+        the related BSON format
+
+    @since version 3.1.0; added @a allow_exceptions parameter since 3.2.0
+    */
+    static basic_json from_ubjson(detail::input_adapter&& i,
+                                  const bool strict = true,
+                                  const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(i)).sax_parse(input_format_t::ubjson, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @copydoc from_ubjson(detail::input_adapter&&, const bool, const bool)
+    */
+    template<typename A1, typename A2,
+             detail::enable_if_t<std::is_constructible<detail::input_adapter, A1, A2>::value, int> = 0>
+    static basic_json from_ubjson(A1 && a1, A2 && a2,
+                                  const bool strict = true,
+                                  const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(std::forward<A1>(a1), std::forward<A2>(a2))).sax_parse(input_format_t::ubjson, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @brief Create a JSON value from an input in BSON format
+
+    Deserializes a given input @a i to a JSON value using the BSON (Binary JSON)
+    serialization format.
+
+    The library maps BSON record types to JSON value types as follows:
+
+    BSON type       | BSON marker byte | JSON value type
+    --------------- | ---------------- | ---------------------------
+    double          | 0x01             | number_float
+    string          | 0x02             | string
+    document        | 0x03             | object
+    array           | 0x04             | array
+    binary          | 0x05             | still unsupported
+    undefined       | 0x06             | still unsupported
+    ObjectId        | 0x07             | still unsupported
+    boolean         | 0x08             | boolean
+    UTC Date-Time   | 0x09             | still unsupported
+    null            | 0x0A             | null
+    Regular Expr.   | 0x0B             | still unsupported
+    DB Pointer      | 0x0C             | still unsupported
+    JavaScript Code | 0x0D             | still unsupported
+    Symbol          | 0x0E             | still unsupported
+    JavaScript Code | 0x0F             | still unsupported
+    int32           | 0x10             | number_integer
+    Timestamp       | 0x11             | still unsupported
+    128-bit decimal float | 0x13       | still unsupported
+    Max Key         | 0x7F             | still unsupported
+    Min Key         | 0xFF             | still unsupported
+
+    @warning The mapping is **incomplete**. The unsupported mappings
+             are indicated in the table above.
+
+    @param[in] i  an input in BSON format convertible to an input adapter
+    @param[in] strict  whether to expect the input to be consumed until EOF
+                       (true by default)
+    @param[in] allow_exceptions  whether to throw exceptions in case of a
+    parse error (optional, true by default)
+
+    @return deserialized JSON value
+
+    @throw parse_error.114 if an unsupported BSON record type is encountered
+
+    @complexity Linear in the size of the input @a i.
+
+    @liveexample{The example shows the deserialization of a byte vector in
+    BSON format to a JSON value.,from_bson}
+
+    @sa http://bsonspec.org/spec.html
+    @sa @ref to_bson(const basic_json&) for the analogous serialization
+    @sa @ref from_cbor(detail::input_adapter&&, const bool, const bool) for the
+        related CBOR format
+    @sa @ref from_msgpack(detail::input_adapter&&, const bool, const bool) for
+        the related MessagePack format
+    @sa @ref from_ubjson(detail::input_adapter&&, const bool, const bool) for the
+        related UBJSON format
+    */
+    static basic_json from_bson(detail::input_adapter&& i,
+                                const bool strict = true,
+                                const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(i)).sax_parse(input_format_t::bson, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+    /*!
+    @copydoc from_bson(detail::input_adapter&&, const bool, const bool)
+    */
+    template<typename A1, typename A2,
+             detail::enable_if_t<std::is_constructible<detail::input_adapter, A1, A2>::value, int> = 0>
+    static basic_json from_bson(A1 && a1, A2 && a2,
+                                const bool strict = true,
+                                const bool allow_exceptions = true)
+    {
+        basic_json result;
+        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
+        const bool res = binary_reader(detail::input_adapter(std::forward<A1>(a1), std::forward<A2>(a2))).sax_parse(input_format_t::bson, &sdp, strict);
+        return res ? result : basic_json(value_t::discarded);
+    }
+
+
+
+    /// @}
+
+    //////////////////////////
+    // JSON Pointer support //
+    //////////////////////////
+
+    /// @name JSON Pointer functions
+    /// @{
+
+    /*!
+    @brief access specified element via JSON Pointer
+
+    Uses a JSON pointer to retrieve a reference to the respective JSON value.
+    No bound checking is performed. Similar to @ref operator[](const typename
+    object_t::key_type&), `null` values are created in arrays and objects if
+    necessary.
+
+    In particular:
+    - If the JSON pointer points to an object key that does not exist, it
+      is created an filled with a `null` value before a reference to it
+      is returned.
+    - If the JSON pointer points to an array index that does not exist, it
+      is created an filled with a `null` value before a reference to it
+      is returned. All indices between the current maximum and the given
+      index are also filled with `null`.
+    - The special value `-` is treated as a synonym for the index past the
+      end.
+
+    @param[in] ptr  a JSON pointer
+
+    @return reference to the element pointed to by @a ptr
+
+    @complexity Constant.
+
+    @throw parse_error.106   if an array index begins with '0'
+    @throw parse_error.109   if an array index was not a number
+    @throw out_of_range.404  if the JSON pointer can not be resolved
+
+    @liveexample{The behavior is shown in the example.,operatorjson_pointer}
+
+    @since version 2.0.0
+    */
+    reference operator[](const json_pointer& ptr)
+    {
+        return ptr.get_unchecked(this);
+    }
+
+    /*!
+    @brief access specified element via JSON Pointer
+
+    Uses a JSON pointer to retrieve a reference to the respective JSON value.
+    No bound checking is performed. The function does not change the JSON
+    value; no `null` values are created. In particular, the the special value
+    `-` yields an exception.
+
+    @param[in] ptr  JSON pointer to the desired element
+
+    @return const reference to the element pointed to by @a ptr
+
+    @complexity Constant.
+
+    @throw parse_error.106   if an array index begins with '0'
+    @throw parse_error.109   if an array index was not a number
+    @throw out_of_range.402  if the array index '-' is used
+    @throw out_of_range.404  if the JSON pointer can not be resolved
+
+    @liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
+
+    @since version 2.0.0
+    */
+    const_reference operator[](const json_pointer& ptr) const
+    {
+        return ptr.get_unchecked(this);
+    }
+
+    /*!
+    @brief access specified element via JSON Pointer
+
+    Returns a reference to the element at with specified JSON pointer @a ptr,
+    with bounds checking.
+
+    @param[in] ptr  JSON pointer to the desired element
+
+    @return reference to the element pointed to by @a ptr
+
+    @throw parse_error.106 if an array index in the passed JSON pointer @a ptr
+    begins with '0'. See example below.
+
+    @throw parse_error.109 if an array index in the passed JSON pointer @a ptr
+    is not a number. See example below.
+
+    @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
+    is out of range. See example below.
+
+    @throw out_of_range.402 if the array index '-' is used in the passed JSON
+    pointer @a ptr. As `at` provides checked access (and no elements are
+    implicitly inserted), the index '-' is always invalid. See example below.
+
+    @throw out_of_range.403 if the JSON pointer describes a key of an object
+    which cannot be found. See example below.
+
+    @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
+    See example below.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Constant.
+
+    @since version 2.0.0
+
+    @liveexample{The behavior is shown in the example.,at_json_pointer}
+    */
+    reference at(const json_pointer& ptr)
+    {
+        return ptr.get_checked(this);
+    }
+
+    /*!
+    @brief access specified element via JSON Pointer
+
+    Returns a const reference to the element at with specified JSON pointer @a
+    ptr, with bounds checking.
+
+    @param[in] ptr  JSON pointer to the desired element
+
+    @return reference to the element pointed to by @a ptr
+
+    @throw parse_error.106 if an array index in the passed JSON pointer @a ptr
+    begins with '0'. See example below.
+
+    @throw parse_error.109 if an array index in the passed JSON pointer @a ptr
+    is not a number. See example below.
+
+    @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
+    is out of range. See example below.
+
+    @throw out_of_range.402 if the array index '-' is used in the passed JSON
+    pointer @a ptr. As `at` provides checked access (and no elements are
+    implicitly inserted), the index '-' is always invalid. See example below.
+
+    @throw out_of_range.403 if the JSON pointer describes a key of an object
+    which cannot be found. See example below.
+
+    @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
+    See example below.
+
+    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
+    changes in the JSON value.
+
+    @complexity Constant.
+
+    @since version 2.0.0
+
+    @liveexample{The behavior is shown in the example.,at_json_pointer_const}
+    */
+    const_reference at(const json_pointer& ptr) const
+    {
+        return ptr.get_checked(this);
+    }
+
+    /*!
+    @brief return flattened JSON value
+
+    The function creates a JSON object whose keys are JSON pointers (see [RFC
+    6901](https://tools.ietf.org/html/rfc6901)) and whose values are all
+    primitive. The original JSON value can be restored using the @ref
+    unflatten() function.
+
+    @return an object that maps JSON pointers to primitive values
+
+    @note Empty objects and arrays are flattened to `null` and will not be
+          reconstructed correctly by the @ref unflatten() function.
+
+    @complexity Linear in the size the JSON value.
+
+    @liveexample{The following code shows how a JSON object is flattened to an
+    object whose keys consist of JSON pointers.,flatten}
+
+    @sa @ref unflatten() for the reverse function
+
+    @since version 2.0.0
+    */
+    basic_json flatten() const
+    {
+        basic_json result(value_t::object);
+        json_pointer::flatten("", *this, result);
+        return result;
+    }
+
+    /*!
+    @brief unflatten a previously flattened JSON value
+
+    The function restores the arbitrary nesting of a JSON value that has been
+    flattened before using the @ref flatten() function. The JSON value must
+    meet certain constraints:
+    1. The value must be an object.
+    2. The keys must be JSON pointers (see
+       [RFC 6901](https://tools.ietf.org/html/rfc6901))
+    3. The mapped values must be primitive JSON types.
+
+    @return the original JSON from a flattened version
+
+    @note Empty objects and arrays are flattened by @ref flatten() to `null`
+          values and can not unflattened to their original type. Apart from
+          this example, for a JSON value `j`, the following is always true:
+          `j == j.flatten().unflatten()`.
+
+    @complexity Linear in the size the JSON value.
+
+    @throw type_error.314  if value is not an object
+    @throw type_error.315  if object values are not primitive
+
+    @liveexample{The following code shows how a flattened JSON object is
+    unflattened into the original nested JSON object.,unflatten}
+
+    @sa @ref flatten() for the reverse function
+
+    @since version 2.0.0
+    */
+    basic_json unflatten() const
+    {
+        return json_pointer::unflatten(*this);
+    }
+
+    /// @}
+
+    //////////////////////////
+    // JSON Patch functions //
+    //////////////////////////
+
+    /// @name JSON Patch functions
+    /// @{
+
+    /*!
+    @brief applies a JSON patch
+
+    [JSON Patch](http://jsonpatch.com) defines a JSON document structure for
+    expressing a sequence of operations to apply to a JSON) document. With
+    this function, a JSON Patch is applied to the current JSON value by
+    executing all operations from the patch.
+
+    @param[in] json_patch  JSON patch document
+    @return patched document
+
+    @note The application of a patch is atomic: Either all operations succeed
+          and the patched document is returned or an exception is thrown. In
+          any case, the original value is not changed: the patch is applied
+          to a copy of the value.
+
+    @throw parse_error.104 if the JSON patch does not consist of an array of
+    objects
+
+    @throw parse_error.105 if the JSON patch is malformed (e.g., mandatory
+    attributes are missing); example: `"operation add must have member path"`
+
+    @throw out_of_range.401 if an array index is out of range.
+
+    @throw out_of_range.403 if a JSON pointer inside the patch could not be
+    resolved successfully in the current JSON value; example: `"key baz not
+    found"`
+
+    @throw out_of_range.405 if JSON pointer has no parent ("add", "remove",
+    "move")
+
+    @throw other_error.501 if "test" operation was unsuccessful
+
+    @complexity Linear in the size of the JSON value and the length of the
+    JSON patch. As usually only a fraction of the JSON value is affected by
+    the patch, the complexity can usually be neglected.
+
+    @liveexample{The following code shows how a JSON patch is applied to a
+    value.,patch}
+
+    @sa @ref diff -- create a JSON patch by comparing two JSON values
+
+    @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
+    @sa [RFC 6901 (JSON Pointer)](https://tools.ietf.org/html/rfc6901)
+
+    @since version 2.0.0
+    */
+    basic_json patch(const basic_json& json_patch) const
+    {
+        // make a working copy to apply the patch to
+        basic_json result = *this;
+
+        // the valid JSON Patch operations
+        enum class patch_operations {add, remove, replace, move, copy, test, invalid};
+
+        const auto get_op = [](const std::string & op)
+        {
+            if (op == "add")
+            {
+                return patch_operations::add;
+            }
+            if (op == "remove")
+            {
+                return patch_operations::remove;
+            }
+            if (op == "replace")
+            {
+                return patch_operations::replace;
+            }
+            if (op == "move")
+            {
+                return patch_operations::move;
+            }
+            if (op == "copy")
+            {
+                return patch_operations::copy;
+            }
+            if (op == "test")
+            {
+                return patch_operations::test;
+            }
+
+            return patch_operations::invalid;
+        };
+
+        // wrapper for "add" operation; add value at ptr
+        const auto operation_add = [&result](json_pointer & ptr, basic_json val)
+        {
+            // adding to the root of the target document means replacing it
+            if (ptr.is_root())
+            {
+                result = val;
+            }
+            else
+            {
+                // make sure the top element of the pointer exists
+                json_pointer top_pointer = ptr.top();
+                if (top_pointer != ptr)
+                {
+                    result.at(top_pointer);
+                }
+
+                // get reference to parent of JSON pointer ptr
+                const auto last_path = ptr.pop_back();
+                basic_json& parent = result[ptr];
+
+                switch (parent.m_type)
+                {
+                    case value_t::null:
+                    case value_t::object:
+                    {
+                        // use operator[] to add value
+                        parent[last_path] = val;
+                        break;
+                    }
+
+                    case value_t::array:
+                    {
+                        if (last_path == "-")
+                        {
+                            // special case: append to back
+                            parent.push_back(val);
+                        }
+                        else
+                        {
+                            const auto idx = json_pointer::array_index(last_path);
+                            if (JSON_UNLIKELY(static_cast<size_type>(idx) > parent.size()))
+                            {
+                                // avoid undefined behavior
+                                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range"));
+                            }
+
+                            // default case: insert add offset
+                            parent.insert(parent.begin() + static_cast<difference_type>(idx), val);
+                        }
+                        break;
+                    }
+
+                    // LCOV_EXCL_START
+                    default:
+                    {
+                        // if there exists a parent it cannot be primitive
+                        assert(false);
+                    }
+                        // LCOV_EXCL_STOP
+                }
+            }
+        };
+
+        // wrapper for "remove" operation; remove value at ptr
+        const auto operation_remove = [&result](json_pointer & ptr)
+        {
+            // get reference to parent of JSON pointer ptr
+            const auto last_path = ptr.pop_back();
+            basic_json& parent = result.at(ptr);
+
+            // remove child
+            if (parent.is_object())
+            {
+                // perform range check
+                auto it = parent.find(last_path);
+                if (JSON_LIKELY(it != parent.end()))
+                {
+                    parent.erase(it);
+                }
+                else
+                {
+                    JSON_THROW(out_of_range::create(403, "key '" + last_path + "' not found"));
+                }
+            }
+            else if (parent.is_array())
+            {
+                // note erase performs range check
+                parent.erase(static_cast<size_type>(json_pointer::array_index(last_path)));
+            }
+        };
+
+        // type check: top level value must be an array
+        if (JSON_UNLIKELY(not json_patch.is_array()))
+        {
+            JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects"));
+        }
+
+        // iterate and apply the operations
+        for (const auto& val : json_patch)
+        {
+            // wrapper to get a value for an operation
+            const auto get_value = [&val](const std::string & op,
+                                          const std::string & member,
+                                          bool string_type) -> basic_json &
+            {
+                // find value
+                auto it = val.m_value.object->find(member);
+
+                // context-sensitive error message
+                const auto error_msg = (op == "op") ? "operation" : "operation '" + op + "'";
+
+                // check if desired value is present
+                if (JSON_UNLIKELY(it == val.m_value.object->end()))
+                {
+                    JSON_THROW(parse_error::create(105, 0, error_msg + " must have member '" + member + "'"));
+                }
+
+                // check if result is of type string
+                if (JSON_UNLIKELY(string_type and not it->second.is_string()))
+                {
+                    JSON_THROW(parse_error::create(105, 0, error_msg + " must have string member '" + member + "'"));
+                }
+
+                // no error: return value
+                return it->second;
+            };
+
+            // type check: every element of the array must be an object
+            if (JSON_UNLIKELY(not val.is_object()))
+            {
+                JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects"));
+            }
+
+            // collect mandatory members
+            const std::string op = get_value("op", "op", true);
+            const std::string path = get_value(op, "path", true);
+            json_pointer ptr(path);
+
+            switch (get_op(op))
+            {
+                case patch_operations::add:
+                {
+                    operation_add(ptr, get_value("add", "value", false));
+                    break;
+                }
+
+                case patch_operations::remove:
+                {
+                    operation_remove(ptr);
+                    break;
+                }
+
+                case patch_operations::replace:
+                {
+                    // the "path" location must exist - use at()
+                    result.at(ptr) = get_value("replace", "value", false);
+                    break;
+                }
+
+                case patch_operations::move:
+                {
+                    const std::string from_path = get_value("move", "from", true);
+                    json_pointer from_ptr(from_path);
+
+                    // the "from" location must exist - use at()
+                    basic_json v = result.at(from_ptr);
+
+                    // The move operation is functionally identical to a
+                    // "remove" operation on the "from" location, followed
+                    // immediately by an "add" operation at the target
+                    // location with the value that was just removed.
+                    operation_remove(from_ptr);
+                    operation_add(ptr, v);
+                    break;
+                }
+
+                case patch_operations::copy:
+                {
+                    const std::string from_path = get_value("copy", "from", true);
+                    const json_pointer from_ptr(from_path);
+
+                    // the "from" location must exist - use at()
+                    basic_json v = result.at(from_ptr);
+
+                    // The copy is functionally identical to an "add"
+                    // operation at the target location using the value
+                    // specified in the "from" member.
+                    operation_add(ptr, v);
+                    break;
+                }
+
+                case patch_operations::test:
+                {
+                    bool success = false;
+                    JSON_TRY
+                    {
+                        // check if "value" matches the one at "path"
+                        // the "path" location must exist - use at()
+                        success = (result.at(ptr) == get_value("test", "value", false));
+                    }
+                    JSON_INTERNAL_CATCH (out_of_range&)
+                    {
+                        // ignore out of range errors: success remains false
+                    }
+
+                    // throw an exception if test fails
+                    if (JSON_UNLIKELY(not success))
+                    {
+                        JSON_THROW(other_error::create(501, "unsuccessful: " + val.dump()));
+                    }
+
+                    break;
+                }
+
+                case patch_operations::invalid:
+                {
+                    // op must be "add", "remove", "replace", "move", "copy", or
+                    // "test"
+                    JSON_THROW(parse_error::create(105, 0, "operation value '" + op + "' is invalid"));
+                }
+            }
+        }
+
+        return result;
+    }
+
+    /*!
+    @brief creates a diff as a JSON patch
+
+    Creates a [JSON Patch](http://jsonpatch.com) so that value @a source can
+    be changed into the value @a target by calling @ref patch function.
+
+    @invariant For two JSON values @a source and @a target, the following code
+    yields always `true`:
+    @code {.cpp}
+    source.patch(diff(source, target)) == target;
+    @endcode
+
+    @note Currently, only `remove`, `add`, and `replace` operations are
+          generated.
+
+    @param[in] source  JSON value to compare from
+    @param[in] target  JSON value to compare against
+    @param[in] path    helper value to create JSON pointers
+
+    @return a JSON patch to convert the @a source to @a target
+
+    @complexity Linear in the lengths of @a source and @a target.
+
+    @liveexample{The following code shows how a JSON patch is created as a
+    diff for two JSON values.,diff}
+
+    @sa @ref patch -- apply a JSON patch
+    @sa @ref merge_patch -- apply a JSON Merge Patch
+
+    @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
+
+    @since version 2.0.0
+    */
+    static basic_json diff(const basic_json& source, const basic_json& target,
+                           const std::string& path = "")
+    {
+        // the patch
+        basic_json result(value_t::array);
+
+        // if the values are the same, return empty patch
+        if (source == target)
+        {
+            return result;
+        }
+
+        if (source.type() != target.type())
+        {
+            // different types: replace value
+            result.push_back(
+            {
+                {"op", "replace"}, {"path", path}, {"value", target}
+            });
+        }
+        else
+        {
+            switch (source.type())
+            {
+                case value_t::array:
+                {
+                    // first pass: traverse common elements
+                    std::size_t i = 0;
+                    while (i < source.size() and i < target.size())
+                    {
+                        // recursive call to compare array values at index i
+                        auto temp_diff = diff(source[i], target[i], path + "/" + std::to_string(i));
+                        result.insert(result.end(), temp_diff.begin(), temp_diff.end());
+                        ++i;
+                    }
+
+                    // i now reached the end of at least one array
+                    // in a second pass, traverse the remaining elements
+
+                    // remove my remaining elements
+                    const auto end_index = static_cast<difference_type>(result.size());
+                    while (i < source.size())
+                    {
+                        // add operations in reverse order to avoid invalid
+                        // indices
+                        result.insert(result.begin() + end_index, object(
+                        {
+                            {"op", "remove"},
+                            {"path", path + "/" + std::to_string(i)}
+                        }));
+                        ++i;
+                    }
+
+                    // add other remaining elements
+                    while (i < target.size())
+                    {
+                        result.push_back(
+                        {
+                            {"op", "add"},
+                            {"path", path + "/" + std::to_string(i)},
+                            {"value", target[i]}
+                        });
+                        ++i;
+                    }
+
+                    break;
+                }
+
+                case value_t::object:
+                {
+                    // first pass: traverse this object's elements
+                    for (auto it = source.cbegin(); it != source.cend(); ++it)
+                    {
+                        // escape the key name to be used in a JSON patch
+                        const auto key = json_pointer::escape(it.key());
+
+                        if (target.find(it.key()) != target.end())
+                        {
+                            // recursive call to compare object values at key it
+                            auto temp_diff = diff(it.value(), target[it.key()], path + "/" + key);
+                            result.insert(result.end(), temp_diff.begin(), temp_diff.end());
+                        }
+                        else
+                        {
+                            // found a key that is not in o -> remove it
+                            result.push_back(object(
+                            {
+                                {"op", "remove"}, {"path", path + "/" + key}
+                            }));
+                        }
+                    }
+
+                    // second pass: traverse other object's elements
+                    for (auto it = target.cbegin(); it != target.cend(); ++it)
+                    {
+                        if (source.find(it.key()) == source.end())
+                        {
+                            // found a key that is not in this -> add it
+                            const auto key = json_pointer::escape(it.key());
+                            result.push_back(
+                            {
+                                {"op", "add"}, {"path", path + "/" + key},
+                                {"value", it.value()}
+                            });
+                        }
+                    }
+
+                    break;
+                }
+
+                default:
+                {
+                    // both primitive type: replace value
+                    result.push_back(
+                    {
+                        {"op", "replace"}, {"path", path}, {"value", target}
+                    });
+                    break;
+                }
+            }
+        }
+
+        return result;
+    }
+
+    /// @}
+
+    ////////////////////////////////
+    // JSON Merge Patch functions //
+    ////////////////////////////////
+
+    /// @name JSON Merge Patch functions
+    /// @{
+
+    /*!
+    @brief applies a JSON Merge Patch
+
+    The merge patch format is primarily intended for use with the HTTP PATCH
+    method as a means of describing a set of modifications to a target
+    resource's content. This function applies a merge patch to the current
+    JSON value.
+
+    The function implements the following algorithm from Section 2 of
+    [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396):
+
+    ```
+    define MergePatch(Target, Patch):
+      if Patch is an Object:
+        if Target is not an Object:
+          Target = {} // Ignore the contents and set it to an empty Object
+        for each Name/Value pair in Patch:
+          if Value is null:
+            if Name exists in Target:
+              remove the Name/Value pair from Target
+          else:
+            Target[Name] = MergePatch(Target[Name], Value)
+        return Target
+      else:
+        return Patch
+    ```
+
+    Thereby, `Target` is the current object; that is, the patch is applied to
+    the current value.
+
+    @param[in] apply_patch  the patch to apply
+
+    @complexity Linear in the lengths of @a patch.
+
+    @liveexample{The following code shows how a JSON Merge Patch is applied to
+    a JSON document.,merge_patch}
+
+    @sa @ref patch -- apply a JSON patch
+    @sa [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396)
+
+    @since version 3.0.0
+    */
+    void merge_patch(const basic_json& apply_patch)
+    {
+        if (apply_patch.is_object())
+        {
+            if (not is_object())
+            {
+                *this = object();
+            }
+            for (auto it = apply_patch.begin(); it != apply_patch.end(); ++it)
+            {
+                if (it.value().is_null())
+                {
+                    erase(it.key());
+                }
+                else
+                {
+                    operator[](it.key()).merge_patch(it.value());
+                }
+            }
+        }
+        else
+        {
+            *this = apply_patch;
+        }
+    }
+
+    /// @}
+};
+} // namespace nlohmann
+
+///////////////////////
+// nonmember support //
+///////////////////////
+
+// specialization of std::swap, and std::hash
+namespace std
+{
+
+/// hash value for JSON objects
+template<>
+struct hash<nlohmann::json>
+{
+    /*!
+    @brief return a hash value for a JSON object
+
+    @since version 1.0.0
+    */
+    std::size_t operator()(const nlohmann::json& j) const
+    {
+        // a naive hashing via the string representation
+        const auto& h = hash<nlohmann::json::string_t>();
+        return h(j.dump());
+    }
+};
+
+/// specialization for std::less<value_t>
+/// @note: do not remove the space after '<',
+///        see https://github.com/nlohmann/json/pull/679
+template<>
+struct less< ::nlohmann::detail::value_t>
+{
+    /*!
+    @brief compare two value_t enum values
+    @since version 3.0.0
+    */
+    bool operator()(nlohmann::detail::value_t lhs,
+                    nlohmann::detail::value_t rhs) const noexcept
+    {
+        return nlohmann::detail::operator<(lhs, rhs);
+    }
+};
+
+/*!
+@brief exchanges the values of two JSON objects
+
+@since version 1.0.0
+*/
+template<>
+inline void swap<nlohmann::json>(nlohmann::json& j1, nlohmann::json& j2) noexcept(
+    is_nothrow_move_constructible<nlohmann::json>::value and
+    is_nothrow_move_assignable<nlohmann::json>::value
+)
+{
+    j1.swap(j2);
+}
+
+} // namespace std
+
+/*!
+@brief user-defined string literal for JSON values
+
+This operator implements a user-defined string literal for JSON objects. It
+can be used by adding `"_json"` to a string literal and returns a JSON object
+if no parse error occurred.
+
+@param[in] s  a string representation of a JSON object
+@param[in] n  the length of string @a s
+@return a JSON object
+
+@since version 1.0.0
+*/
+inline nlohmann::json operator "" _json(const char* s, std::size_t n)
+{
+    return nlohmann::json::parse(s, s + n);
+}
+
+/*!
+@brief user-defined string literal for JSON pointer
+
+This operator implements a user-defined string literal for JSON Pointers. It
+can be used by adding `"_json_pointer"` to a string literal and returns a JSON pointer
+object if no parse error occurred.
+
+@param[in] s  a string representation of a JSON Pointer
+@param[in] n  the length of string @a s
+@return a JSON pointer object
+
+@since version 2.0.0
+*/
+inline nlohmann::json::json_pointer operator "" _json_pointer(const char* s, std::size_t n)
+{
+    return nlohmann::json::json_pointer(std::string(s, n));
+}
+
+// #include <nlohmann/detail/macro_unscope.hpp>
+
+
+// restore GCC/clang diagnostic settings
+#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__)
+    #pragma GCC diagnostic pop
+#endif
+#if defined(__clang__)
+    #pragma GCC diagnostic pop
+#endif
+
+// clean up
+#undef JSON_INTERNAL_CATCH
+#undef JSON_CATCH
+#undef JSON_THROW
+#undef JSON_TRY
+#undef JSON_LIKELY
+#undef JSON_UNLIKELY
+#undef JSON_DEPRECATED
+#undef JSON_HAS_CPP_14
+#undef JSON_HAS_CPP_17
+#undef NLOHMANN_BASIC_JSON_TPL_DECLARATION
+#undef NLOHMANN_BASIC_JSON_TPL
+
+
+#endif
diff --git a/engine/inc/gltf/stb_image.h b/engine/inc/gltf/stb_image.h
new file mode 100644
index 00000000..8b710609
--- /dev/null
+++ b/engine/inc/gltf/stb_image.h
@@ -0,0 +1,7530 @@
+/* stb_image - v2.21 - public domain image loader - http://nothings.org/stb
+                                  no warranty implied; use at your own risk
+
+   Do this:
+      #define STB_IMAGE_IMPLEMENTATION
+   before you include this file in *one* C or C++ file to create the implementation.
+
+   // i.e. it should look like this:
+   #include ...
+   #include ...
+   #include ...
+   #define STB_IMAGE_IMPLEMENTATION
+   #include "stb_image.h"
+
+   You can #define STBI_ASSERT(x) before the #include to avoid using assert.h.
+   And #define STBI_MALLOC, STBI_REALLOC, and STBI_FREE to avoid using malloc,realloc,free
+
+
+   QUICK NOTES:
+      Primarily of interest to game developers and other people who can
+          avoid problematic images and only need the trivial interface
+
+      JPEG baseline & progressive (12 bpc/arithmetic not supported, same as stock IJG lib)
+      PNG 1/2/4/8/16-bit-per-channel
+
+      TGA (not sure what subset, if a subset)
+      BMP non-1bpp, non-RLE
+      PSD (composited view only, no extra channels, 8/16 bit-per-channel)
+
+      GIF (*comp always reports as 4-channel)
+      HDR (radiance rgbE format)
+      PIC (Softimage PIC)
+      PNM (PPM and PGM binary only)
+
+      Animated GIF still needs a proper API, but here's one way to do it:
+          http://gist.github.com/urraka/685d9a6340b26b830d49
+
+      - decode from memory or through FILE (define STBI_NO_STDIO to remove code)
+      - decode from arbitrary I/O callbacks
+      - SIMD acceleration on x86/x64 (SSE2) and ARM (NEON)
+
+   Full documentation under "DOCUMENTATION" below.
+
+
+LICENSE
+
+  See end of file for license information.
+
+RECENT REVISION HISTORY:
+
+      2.21  (2019-02-25) fix typo in comment
+      2.20  (2019-02-07) support utf8 filenames in Windows; fix warnings and platform ifdefs 
+      2.19  (2018-02-11) fix warning
+      2.18  (2018-01-30) fix warnings
+      2.17  (2018-01-29) bugfix, 1-bit BMP, 16-bitness query, fix warnings
+      2.16  (2017-07-23) all functions have 16-bit variants; optimizations; bugfixes
+      2.15  (2017-03-18) fix png-1,2,4; all Imagenet JPGs; no runtime SSE detection on GCC
+      2.14  (2017-03-03) remove deprecated STBI_JPEG_OLD; fixes for Imagenet JPGs
+      2.13  (2016-12-04) experimental 16-bit API, only for PNG so far; fixes
+      2.12  (2016-04-02) fix typo in 2.11 PSD fix that caused crashes
+      2.11  (2016-04-02) 16-bit PNGS; enable SSE2 in non-gcc x64
+                         RGB-format JPEG; remove white matting in PSD;
+                         allocate large structures on the stack;
+                         correct channel count for PNG & BMP
+      2.10  (2016-01-22) avoid warning introduced in 2.09
+      2.09  (2016-01-16) 16-bit TGA; comments in PNM files; STBI_REALLOC_SIZED
+
+   See end of file for full revision history.
+
+
+ ============================    Contributors    =========================
+
+ Image formats                          Extensions, features
+    Sean Barrett (jpeg, png, bmp)          Jetro Lauha (stbi_info)
+    Nicolas Schulz (hdr, psd)              Martin "SpartanJ" Golini (stbi_info)
+    Jonathan Dummer (tga)                  James "moose2000" Brown (iPhone PNG)
+    Jean-Marc Lienher (gif)                Ben "Disch" Wenger (io callbacks)
+    Tom Seddon (pic)                       Omar Cornut (1/2/4-bit PNG)
+    Thatcher Ulrich (psd)                  Nicolas Guillemot (vertical flip)
+    Ken Miller (pgm, ppm)                  Richard Mitton (16-bit PSD)
+    github:urraka (animated gif)           Junggon Kim (PNM comments)
+    Christopher Forseth (animated gif)     Daniel Gibson (16-bit TGA)
+                                           socks-the-fox (16-bit PNG)
+                                           Jeremy Sawicki (handle all ImageNet JPGs)
+ Optimizations & bugfixes                  Mikhail Morozov (1-bit BMP)
+    Fabian "ryg" Giesen                    Anael Seghezzi (is-16-bit query)
+    Arseny Kapoulkine
+    John-Mark Allen
+    Carmelo J Fdez-Aguera
+
+ Bug & warning fixes
+    Marc LeBlanc            David Woo          Guillaume George   Martins Mozeiko
+    Christpher Lloyd        Jerry Jansson      Joseph Thomson     Phil Jordan
+    Dave Moore              Roy Eltham         Hayaki Saito       Nathan Reed
+    Won Chun                Luke Graham        Johan Duparc       Nick Verigakis
+    the Horde3D community   Thomas Ruf         Ronny Chevalier    github:rlyeh
+    Janez Zemva             John Bartholomew   Michal Cichon      github:romigrou
+    Jonathan Blow           Ken Hamada         Tero Hanninen      github:svdijk
+    Laurent Gomila          Cort Stratton      Sergio Gonzalez    github:snagar
+    Aruelien Pocheville     Thibault Reuille   Cass Everitt       github:Zelex
+    Ryamond Barbiero        Paul Du Bois       Engin Manap        github:grim210
+    Aldo Culquicondor       Philipp Wiesemann  Dale Weiler        github:sammyhw
+    Oriol Ferrer Mesia      Josh Tobin         Matthew Gregan     github:phprus
+    Julian Raschke          Gregory Mullen     Baldur Karlsson    github:poppolopoppo
+    Christian Floisand      Kevin Schmidt      JR Smith           github:darealshinji
+    Blazej Dariusz Roszkowski                                     github:Michaelangel007
+*/
+
+#ifndef STBI_INCLUDE_STB_IMAGE_H
+#define STBI_INCLUDE_STB_IMAGE_H
+
+// DOCUMENTATION
+//
+// Limitations:
+//    - no 12-bit-per-channel JPEG
+//    - no JPEGs with arithmetic coding
+//    - GIF always returns *comp=4
+//
+// Basic usage (see HDR discussion below for HDR usage):
+//    int x,y,n;
+//    unsigned char *data = stbi_load(filename, &x, &y, &n, 0);
+//    // ... process data if not NULL ...
+//    // ... x = width, y = height, n = # 8-bit components per pixel ...
+//    // ... replace '0' with '1'..'4' to force that many components per pixel
+//    // ... but 'n' will always be the number that it would have been if you said 0
+//    stbi_image_free(data)
+//
+// Standard parameters:
+//    int *x                 -- outputs image width in pixels
+//    int *y                 -- outputs image height in pixels
+//    int *channels_in_file  -- outputs # of image components in image file
+//    int desired_channels   -- if non-zero, # of image components requested in result
+//
+// The return value from an image loader is an 'unsigned char *' which points
+// to the pixel data, or NULL on an allocation failure or if the image is
+// corrupt or invalid. The pixel data consists of *y scanlines of *x pixels,
+// with each pixel consisting of N interleaved 8-bit components; the first
+// pixel pointed to is top-left-most in the image. There is no padding between
+// image scanlines or between pixels, regardless of format. The number of
+// components N is 'desired_channels' if desired_channels is non-zero, or
+// *channels_in_file otherwise. If desired_channels is non-zero,
+// *channels_in_file has the number of components that _would_ have been
+// output otherwise. E.g. if you set desired_channels to 4, you will always
+// get RGBA output, but you can check *channels_in_file to see if it's trivially
+// opaque because e.g. there were only 3 channels in the source image.
+//
+// An output image with N components has the following components interleaved
+// in this order in each pixel:
+//
+//     N=#comp     components
+//       1           grey
+//       2           grey, alpha
+//       3           red, green, blue
+//       4           red, green, blue, alpha
+//
+// If image loading fails for any reason, the return value will be NULL,
+// and *x, *y, *channels_in_file will be unchanged. The function
+// stbi_failure_reason() can be queried for an extremely brief, end-user
+// unfriendly explanation of why the load failed. Define STBI_NO_FAILURE_STRINGS
+// to avoid compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly
+// more user-friendly ones.
+//
+// Paletted PNG, BMP, GIF, and PIC images are automatically depalettized.
+//
+// ===========================================================================
+//
+// UNICODE:
+//
+//   If compiling for Windows and you wish to use Unicode filenames, compile
+//   with
+//       #define STBI_WINDOWS_UTF8
+//   and pass utf8-encoded filenames. Call stbi_convert_wchar_to_utf8 to convert
+//   Windows wchar_t filenames to utf8.
+//
+// ===========================================================================
+//
+// Philosophy
+//
+// stb libraries are designed with the following priorities:
+//
+//    1. easy to use
+//    2. easy to maintain
+//    3. good performance
+//
+// Sometimes I let "good performance" creep up in priority over "easy to maintain",
+// and for best performance I may provide less-easy-to-use APIs that give higher
+// performance, in addition to the easy-to-use ones. Nevertheless, it's important
+// to keep in mind that from the standpoint of you, a client of this library,
+// all you care about is #1 and #3, and stb libraries DO NOT emphasize #3 above all.
+//
+// Some secondary priorities arise directly from the first two, some of which
+// provide more explicit reasons why performance can't be emphasized.
+//
+//    - Portable ("ease of use")
+//    - Small source code footprint ("easy to maintain")
+//    - No dependencies ("ease of use")
+//
+// ===========================================================================
+//
+// I/O callbacks
+//
+// I/O callbacks allow you to read from arbitrary sources, like packaged
+// files or some other source. Data read from callbacks are processed
+// through a small internal buffer (currently 128 bytes) to try to reduce
+// overhead.
+//
+// The three functions you must define are "read" (reads some bytes of data),
+// "skip" (skips some bytes of data), "eof" (reports if the stream is at the end).
+//
+// ===========================================================================
+//
+// SIMD support
+//
+// The JPEG decoder will try to automatically use SIMD kernels on x86 when
+// supported by the compiler. For ARM Neon support, you must explicitly
+// request it.
+//
+// (The old do-it-yourself SIMD API is no longer supported in the current
+// code.)
+//
+// On x86, SSE2 will automatically be used when available based on a run-time
+// test; if not, the generic C versions are used as a fall-back. On ARM targets,
+// the typical path is to have separate builds for NEON and non-NEON devices
+// (at least this is true for iOS and Android). Therefore, the NEON support is
+// toggled by a build flag: define STBI_NEON to get NEON loops.
+//
+// If for some reason you do not want to use any of SIMD code, or if
+// you have issues compiling it, you can disable it entirely by
+// defining STBI_NO_SIMD.
+//
+// ===========================================================================
+//
+// HDR image support   (disable by defining STBI_NO_HDR)
+//
+// stb_image supports loading HDR images in general, and currently the Radiance
+// .HDR file format specifically. You can still load any file through the existing
+// interface; if you attempt to load an HDR file, it will be automatically remapped
+// to LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1;
+// both of these constants can be reconfigured through this interface:
+//
+//     stbi_hdr_to_ldr_gamma(2.2f);
+//     stbi_hdr_to_ldr_scale(1.0f);
+//
+// (note, do not use _inverse_ constants; stbi_image will invert them
+// appropriately).
+//
+// Additionally, there is a new, parallel interface for loading files as
+// (linear) floats to preserve the full dynamic range:
+//
+//    float *data = stbi_loadf(filename, &x, &y, &n, 0);
+//
+// If you load LDR images through this interface, those images will
+// be promoted to floating point values, run through the inverse of
+// constants corresponding to the above:
+//
+//     stbi_ldr_to_hdr_scale(1.0f);
+//     stbi_ldr_to_hdr_gamma(2.2f);
+//
+// Finally, given a filename (or an open file or memory block--see header
+// file for details) containing image data, you can query for the "most
+// appropriate" interface to use (that is, whether the image is HDR or
+// not), using:
+//
+//     stbi_is_hdr(char *filename);
+//
+// ===========================================================================
+//
+// iPhone PNG support:
+//
+// By default we convert iphone-formatted PNGs back to RGB, even though
+// they are internally encoded differently. You can disable this conversion
+// by calling stbi_convert_iphone_png_to_rgb(0), in which case
+// you will always just get the native iphone "format" through (which
+// is BGR stored in RGB).
+//
+// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per
+// pixel to remove any premultiplied alpha *only* if the image file explicitly
+// says there's premultiplied data (currently only happens in iPhone images,
+// and only if iPhone convert-to-rgb processing is on).
+//
+// ===========================================================================
+//
+// ADDITIONAL CONFIGURATION
+//
+//  - You can suppress implementation of any of the decoders to reduce
+//    your code footprint by #defining one or more of the following
+//    symbols before creating the implementation.
+//
+//        STBI_NO_JPEG
+//        STBI_NO_PNG
+//        STBI_NO_BMP
+//        STBI_NO_PSD
+//        STBI_NO_TGA
+//        STBI_NO_GIF
+//        STBI_NO_HDR
+//        STBI_NO_PIC
+//        STBI_NO_PNM   (.ppm and .pgm)
+//
+//  - You can request *only* certain decoders and suppress all other ones
+//    (this will be more forward-compatible, as addition of new decoders
+//    doesn't require you to disable them explicitly):
+//
+//        STBI_ONLY_JPEG
+//        STBI_ONLY_PNG
+//        STBI_ONLY_BMP
+//        STBI_ONLY_PSD
+//        STBI_ONLY_TGA
+//        STBI_ONLY_GIF
+//        STBI_ONLY_HDR
+//        STBI_ONLY_PIC
+//        STBI_ONLY_PNM   (.ppm and .pgm)
+//
+//   - If you use STBI_NO_PNG (or _ONLY_ without PNG), and you still
+//     want the zlib decoder to be available, #define STBI_SUPPORT_ZLIB
+//
+
+
+#ifndef STBI_NO_STDIO
+#include <stdio.h>
+#endif // STBI_NO_STDIO
+
+#define STBI_VERSION 1
+
+enum
+{
+   STBI_default = 0, // only used for desired_channels
+
+   STBI_grey       = 1,
+   STBI_grey_alpha = 2,
+   STBI_rgb        = 3,
+   STBI_rgb_alpha  = 4
+};
+
+#include <stdlib.h>
+typedef unsigned char stbi_uc;
+typedef unsigned short stbi_us;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef STB_IMAGE_STATIC
+#define STBIDEF static
+#else
+#define STBIDEF extern
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// PRIMARY API - works on images of any type
+//
+
+//
+// load image by filename, open file, or memory buffer
+//
+
+typedef struct
+{
+   int      (*read)  (void *user,char *data,int size);   // fill 'data' with 'size' bytes.  return number of bytes actually read
+   void     (*skip)  (void *user,int n);                 // skip the next 'n' bytes, or 'unget' the last -n bytes if negative
+   int      (*eof)   (void *user);                       // returns nonzero if we are at end of file/data
+} stbi_io_callbacks;
+
+////////////////////////////////////
+//
+// 8-bits-per-channel interface
+//
+
+STBIDEF stbi_uc *stbi_load_from_memory   (stbi_uc           const *buffer, int len   , int *x, int *y, int *channels_in_file, int desired_channels);
+STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk  , void *user, int *x, int *y, int *channels_in_file, int desired_channels);
+
+#ifndef STBI_NO_STDIO
+STBIDEF stbi_uc *stbi_load            (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels);
+STBIDEF stbi_uc *stbi_load_from_file  (FILE *f, int *x, int *y, int *channels_in_file, int desired_channels);
+// for stbi_load_from_file, file pointer is left pointing immediately after image
+#endif
+
+#ifndef STBI_NO_GIF
+STBIDEF stbi_uc *stbi_load_gif_from_memory(stbi_uc const *buffer, int len, int **delays, int *x, int *y, int *z, int *comp, int req_comp);
+#endif
+
+#ifdef STBI_WINDOWS_UTF8
+STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input);
+#endif
+
+////////////////////////////////////
+//
+// 16-bits-per-channel interface
+//
+
+STBIDEF stbi_us *stbi_load_16_from_memory   (stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels);
+STBIDEF stbi_us *stbi_load_16_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels);
+
+#ifndef STBI_NO_STDIO
+STBIDEF stbi_us *stbi_load_16          (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels);
+STBIDEF stbi_us *stbi_load_from_file_16(FILE *f, int *x, int *y, int *channels_in_file, int desired_channels);
+#endif
+
+////////////////////////////////////
+//
+// float-per-channel interface
+//
+#ifndef STBI_NO_LINEAR
+   STBIDEF float *stbi_loadf_from_memory     (stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels);
+   STBIDEF float *stbi_loadf_from_callbacks  (stbi_io_callbacks const *clbk, void *user, int *x, int *y,  int *channels_in_file, int desired_channels);
+
+   #ifndef STBI_NO_STDIO
+   STBIDEF float *stbi_loadf            (char const *filename, int *x, int *y, int *channels_in_file, int desired_channels);
+   STBIDEF float *stbi_loadf_from_file  (FILE *f, int *x, int *y, int *channels_in_file, int desired_channels);
+   #endif
+#endif
+
+#ifndef STBI_NO_HDR
+   STBIDEF void   stbi_hdr_to_ldr_gamma(float gamma);
+   STBIDEF void   stbi_hdr_to_ldr_scale(float scale);
+#endif // STBI_NO_HDR
+
+#ifndef STBI_NO_LINEAR
+   STBIDEF void   stbi_ldr_to_hdr_gamma(float gamma);
+   STBIDEF void   stbi_ldr_to_hdr_scale(float scale);
+#endif // STBI_NO_LINEAR
+
+// stbi_is_hdr is always defined, but always returns false if STBI_NO_HDR
+STBIDEF int    stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user);
+STBIDEF int    stbi_is_hdr_from_memory(stbi_uc const *buffer, int len);
+#ifndef STBI_NO_STDIO
+STBIDEF int      stbi_is_hdr          (char const *filename);
+STBIDEF int      stbi_is_hdr_from_file(FILE *f);
+#endif // STBI_NO_STDIO
+
+
+// get a VERY brief reason for failure
+// NOT THREADSAFE
+STBIDEF const char *stbi_failure_reason  (void);
+
+// free the loaded image -- this is just free()
+STBIDEF void     stbi_image_free      (void *retval_from_stbi_load);
+
+// get image dimensions & components without fully decoding
+STBIDEF int      stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
+STBIDEF int      stbi_info_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp);
+STBIDEF int      stbi_is_16_bit_from_memory(stbi_uc const *buffer, int len);
+STBIDEF int      stbi_is_16_bit_from_callbacks(stbi_io_callbacks const *clbk, void *user);
+
+#ifndef STBI_NO_STDIO
+STBIDEF int      stbi_info               (char const *filename,     int *x, int *y, int *comp);
+STBIDEF int      stbi_info_from_file     (FILE *f,                  int *x, int *y, int *comp);
+STBIDEF int      stbi_is_16_bit          (char const *filename);
+STBIDEF int      stbi_is_16_bit_from_file(FILE *f);
+#endif
+
+
+
+// for image formats that explicitly notate that they have premultiplied alpha,
+// we just return the colors as stored in the file. set this flag to force
+// unpremultiplication. results are undefined if the unpremultiply overflow.
+STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply);
+
+// indicate whether we should process iphone images back to canonical format,
+// or just pass them through "as-is"
+STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert);
+
+// flip the image vertically, so the first pixel in the output array is the bottom left
+STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip);
+
+// ZLIB client - used by PNG, available for other purposes
+
+STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen);
+STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header);
+STBIDEF char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen);
+STBIDEF int   stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
+
+STBIDEF char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen);
+STBIDEF int   stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+//
+//
+////   end header file   /////////////////////////////////////////////////////
+#endif // STBI_INCLUDE_STB_IMAGE_H
+
+#ifdef STB_IMAGE_IMPLEMENTATION
+
+#if defined(STBI_ONLY_JPEG) || defined(STBI_ONLY_PNG) || defined(STBI_ONLY_BMP) \
+  || defined(STBI_ONLY_TGA) || defined(STBI_ONLY_GIF) || defined(STBI_ONLY_PSD) \
+  || defined(STBI_ONLY_HDR) || defined(STBI_ONLY_PIC) || defined(STBI_ONLY_PNM) \
+  || defined(STBI_ONLY_ZLIB)
+   #ifndef STBI_ONLY_JPEG
+   #define STBI_NO_JPEG
+   #endif
+   #ifndef STBI_ONLY_PNG
+   #define STBI_NO_PNG
+   #endif
+   #ifndef STBI_ONLY_BMP
+   #define STBI_NO_BMP
+   #endif
+   #ifndef STBI_ONLY_PSD
+   #define STBI_NO_PSD
+   #endif
+   #ifndef STBI_ONLY_TGA
+   #define STBI_NO_TGA
+   #endif
+   #ifndef STBI_ONLY_GIF
+   #define STBI_NO_GIF
+   #endif
+   #ifndef STBI_ONLY_HDR
+   #define STBI_NO_HDR
+   #endif
+   #ifndef STBI_ONLY_PIC
+   #define STBI_NO_PIC
+   #endif
+   #ifndef STBI_ONLY_PNM
+   #define STBI_NO_PNM
+   #endif
+#endif
+
+#if defined(STBI_NO_PNG) && !defined(STBI_SUPPORT_ZLIB) && !defined(STBI_NO_ZLIB)
+#define STBI_NO_ZLIB
+#endif
+
+
+#include <stdarg.h>
+#include <stddef.h> // ptrdiff_t on osx
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
+#include <math.h>  // ldexp, pow
+#endif
+
+#ifndef STBI_NO_STDIO
+#include <stdio.h>
+#endif
+
+#ifndef STBI_ASSERT
+#include <assert.h>
+#define STBI_ASSERT(x) assert(x)
+#endif
+
+#ifdef __cplusplus
+#define STBI_EXTERN extern "C"
+#else
+#define STBI_EXTERN extern
+#endif
+
+
+#ifndef _MSC_VER
+   #ifdef __cplusplus
+   #define stbi_inline inline
+   #else
+   #define stbi_inline
+   #endif
+#else
+   #define stbi_inline __forceinline
+#endif
+
+
+#ifdef _MSC_VER
+typedef unsigned short stbi__uint16;
+typedef   signed short stbi__int16;
+typedef unsigned int   stbi__uint32;
+typedef   signed int   stbi__int32;
+#else
+#include <stdint.h>
+typedef uint16_t stbi__uint16;
+typedef int16_t  stbi__int16;
+typedef uint32_t stbi__uint32;
+typedef int32_t  stbi__int32;
+#endif
+
+// should produce compiler error if size is wrong
+typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1];
+
+#ifdef _MSC_VER
+#define STBI_NOTUSED(v)  (void)(v)
+#else
+#define STBI_NOTUSED(v)  (void)sizeof(v)
+#endif
+
+#ifdef _MSC_VER
+#define STBI_HAS_LROTL
+#endif
+
+#ifdef STBI_HAS_LROTL
+   #define stbi_lrot(x,y)  _lrotl(x,y)
+#else
+   #define stbi_lrot(x,y)  (((x) << (y)) | ((x) >> (32 - (y))))
+#endif
+
+#if defined(STBI_MALLOC) && defined(STBI_FREE) && (defined(STBI_REALLOC) || defined(STBI_REALLOC_SIZED))
+// ok
+#elif !defined(STBI_MALLOC) && !defined(STBI_FREE) && !defined(STBI_REALLOC) && !defined(STBI_REALLOC_SIZED)
+// ok
+#else
+#error "Must define all or none of STBI_MALLOC, STBI_FREE, and STBI_REALLOC (or STBI_REALLOC_SIZED)."
+#endif
+
+#ifndef STBI_MALLOC
+#define STBI_MALLOC(sz)           malloc(sz)
+#define STBI_REALLOC(p,newsz)     realloc(p,newsz)
+#define STBI_FREE(p)              free(p)
+#endif
+
+#ifndef STBI_REALLOC_SIZED
+#define STBI_REALLOC_SIZED(p,oldsz,newsz) STBI_REALLOC(p,newsz)
+#endif
+
+// x86/x64 detection
+#if defined(__x86_64__) || defined(_M_X64)
+#define STBI__X64_TARGET
+#elif defined(__i386) || defined(_M_IX86)
+#define STBI__X86_TARGET
+#endif
+
+#if defined(__GNUC__) && defined(STBI__X86_TARGET) && !defined(__SSE2__) && !defined(STBI_NO_SIMD)
+// gcc doesn't support sse2 intrinsics unless you compile with -msse2,
+// which in turn means it gets to use SSE2 everywhere. This is unfortunate,
+// but previous attempts to provide the SSE2 functions with runtime
+// detection caused numerous issues. The way architecture extensions are
+// exposed in GCC/Clang is, sadly, not really suited for one-file libs.
+// New behavior: if compiled with -msse2, we use SSE2 without any
+// detection; if not, we don't use it at all.
+#define STBI_NO_SIMD
+#endif
+
+#if defined(__MINGW32__) && defined(STBI__X86_TARGET) && !defined(STBI_MINGW_ENABLE_SSE2) && !defined(STBI_NO_SIMD)
+// Note that __MINGW32__ doesn't actually mean 32-bit, so we have to avoid STBI__X64_TARGET
+//
+// 32-bit MinGW wants ESP to be 16-byte aligned, but this is not in the
+// Windows ABI and VC++ as well as Windows DLLs don't maintain that invariant.
+// As a result, enabling SSE2 on 32-bit MinGW is dangerous when not
+// simultaneously enabling "-mstackrealign".
+//
+// See https://github.com/nothings/stb/issues/81 for more information.
+//
+// So default to no SSE2 on 32-bit MinGW. If you've read this far and added
+// -mstackrealign to your build settings, feel free to #define STBI_MINGW_ENABLE_SSE2.
+#define STBI_NO_SIMD
+#endif
+
+#if !defined(STBI_NO_SIMD) && (defined(STBI__X86_TARGET) || defined(STBI__X64_TARGET))
+#define STBI_SSE2
+#include <emmintrin.h>
+
+#ifdef _MSC_VER
+
+#if _MSC_VER >= 1400  // not VC6
+#include <intrin.h> // __cpuid
+static int stbi__cpuid3(void)
+{
+   int info[4];
+   __cpuid(info,1);
+   return info[3];
+}
+#else
+static int stbi__cpuid3(void)
+{
+   int res;
+   __asm {
+      mov  eax,1
+      cpuid
+      mov  res,edx
+   }
+   return res;
+}
+#endif
+
+#define STBI_SIMD_ALIGN(type, name) __declspec(align(16)) type name
+
+#if !defined(STBI_NO_JPEG) && defined(STBI_SSE2)
+static int stbi__sse2_available(void)
+{
+   int info3 = stbi__cpuid3();
+   return ((info3 >> 26) & 1) != 0;
+}
+#endif
+
+#else // assume GCC-style if not VC++
+#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
+
+#if !defined(STBI_NO_JPEG) && defined(STBI_SSE2)
+static int stbi__sse2_available(void)
+{
+   // If we're even attempting to compile this on GCC/Clang, that means
+   // -msse2 is on, which means the compiler is allowed to use SSE2
+   // instructions at will, and so are we.
+   return 1;
+}
+#endif
+
+#endif
+#endif
+
+// ARM NEON
+#if defined(STBI_NO_SIMD) && defined(STBI_NEON)
+#undef STBI_NEON
+#endif
+
+#ifdef STBI_NEON
+#include <arm_neon.h>
+// assume GCC or Clang on ARM targets
+#define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
+#endif
+
+#ifndef STBI_SIMD_ALIGN
+#define STBI_SIMD_ALIGN(type, name) type name
+#endif
+
+///////////////////////////////////////////////
+//
+//  stbi__context struct and start_xxx functions
+
+// stbi__context structure is our basic context used by all images, so it
+// contains all the IO context, plus some basic image information
+typedef struct
+{
+   stbi__uint32 img_x, img_y;
+   int img_n, img_out_n;
+
+   stbi_io_callbacks io;
+   void *io_user_data;
+
+   int read_from_callbacks;
+   int buflen;
+   stbi_uc buffer_start[128];
+
+   stbi_uc *img_buffer, *img_buffer_end;
+   stbi_uc *img_buffer_original, *img_buffer_original_end;
+} stbi__context;
+
+
+static void stbi__refill_buffer(stbi__context *s);
+
+// initialize a memory-decode context
+static void stbi__start_mem(stbi__context *s, stbi_uc const *buffer, int len)
+{
+   s->io.read = NULL;
+   s->read_from_callbacks = 0;
+   s->img_buffer = s->img_buffer_original = (stbi_uc *) buffer;
+   s->img_buffer_end = s->img_buffer_original_end = (stbi_uc *) buffer+len;
+}
+
+// initialize a callback-based context
+static void stbi__start_callbacks(stbi__context *s, stbi_io_callbacks *c, void *user)
+{
+   s->io = *c;
+   s->io_user_data = user;
+   s->buflen = sizeof(s->buffer_start);
+   s->read_from_callbacks = 1;
+   s->img_buffer_original = s->buffer_start;
+   stbi__refill_buffer(s);
+   s->img_buffer_original_end = s->img_buffer_end;
+}
+
+#ifndef STBI_NO_STDIO
+
+static int stbi__stdio_read(void *user, char *data, int size)
+{
+   return (int) fread(data,1,size,(FILE*) user);
+}
+
+static void stbi__stdio_skip(void *user, int n)
+{
+   fseek((FILE*) user, n, SEEK_CUR);
+}
+
+static int stbi__stdio_eof(void *user)
+{
+   return feof((FILE*) user);
+}
+
+static stbi_io_callbacks stbi__stdio_callbacks =
+{
+   stbi__stdio_read,
+   stbi__stdio_skip,
+   stbi__stdio_eof,
+};
+
+static void stbi__start_file(stbi__context *s, FILE *f)
+{
+   stbi__start_callbacks(s, &stbi__stdio_callbacks, (void *) f);
+}
+
+//static void stop_file(stbi__context *s) { }
+
+#endif // !STBI_NO_STDIO
+
+static void stbi__rewind(stbi__context *s)
+{
+   // conceptually rewind SHOULD rewind to the beginning of the stream,
+   // but we just rewind to the beginning of the initial buffer, because
+   // we only use it after doing 'test', which only ever looks at at most 92 bytes
+   s->img_buffer = s->img_buffer_original;
+   s->img_buffer_end = s->img_buffer_original_end;
+}
+
+enum
+{
+   STBI_ORDER_RGB,
+   STBI_ORDER_BGR
+};
+
+typedef struct
+{
+   int bits_per_channel;
+   int num_channels;
+   int channel_order;
+} stbi__result_info;
+
+#ifndef STBI_NO_JPEG
+static int      stbi__jpeg_test(stbi__context *s);
+static void    *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+#ifndef STBI_NO_PNG
+static int      stbi__png_test(stbi__context *s);
+static void    *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__png_info(stbi__context *s, int *x, int *y, int *comp);
+static int      stbi__png_is16(stbi__context *s);
+#endif
+
+#ifndef STBI_NO_BMP
+static int      stbi__bmp_test(stbi__context *s);
+static void    *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+#ifndef STBI_NO_TGA
+static int      stbi__tga_test(stbi__context *s);
+static void    *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__tga_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+#ifndef STBI_NO_PSD
+static int      stbi__psd_test(stbi__context *s);
+static void    *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc);
+static int      stbi__psd_info(stbi__context *s, int *x, int *y, int *comp);
+static int      stbi__psd_is16(stbi__context *s);
+#endif
+
+#ifndef STBI_NO_HDR
+static int      stbi__hdr_test(stbi__context *s);
+static float   *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+#ifndef STBI_NO_PIC
+static int      stbi__pic_test(stbi__context *s);
+static void    *stbi__pic_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__pic_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+#ifndef STBI_NO_GIF
+static int      stbi__gif_test(stbi__context *s);
+static void    *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static void    *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp);
+static int      stbi__gif_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+#ifndef STBI_NO_PNM
+static int      stbi__pnm_test(stbi__context *s);
+static void    *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
+static int      stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp);
+#endif
+
+// this is not threadsafe
+static const char *stbi__g_failure_reason;
+
+STBIDEF const char *stbi_failure_reason(void)
+{
+   return stbi__g_failure_reason;
+}
+
+static int stbi__err(const char *str)
+{
+   stbi__g_failure_reason = str;
+   return 0;
+}
+
+static void *stbi__malloc(size_t size)
+{
+    return STBI_MALLOC(size);
+}
+
+// stb_image uses ints pervasively, including for offset calculations.
+// therefore the largest decoded image size we can support with the
+// current code, even on 64-bit targets, is INT_MAX. this is not a
+// significant limitation for the intended use case.
+//
+// we do, however, need to make sure our size calculations don't
+// overflow. hence a few helper functions for size calculations that
+// multiply integers together, making sure that they're non-negative
+// and no overflow occurs.
+
+// return 1 if the sum is valid, 0 on overflow.
+// negative terms are considered invalid.
+static int stbi__addsizes_valid(int a, int b)
+{
+   if (b < 0) return 0;
+   // now 0 <= b <= INT_MAX, hence also
+   // 0 <= INT_MAX - b <= INTMAX.
+   // And "a + b <= INT_MAX" (which might overflow) is the
+   // same as a <= INT_MAX - b (no overflow)
+   return a <= INT_MAX - b;
+}
+
+// returns 1 if the product is valid, 0 on overflow.
+// negative factors are considered invalid.
+static int stbi__mul2sizes_valid(int a, int b)
+{
+   if (a < 0 || b < 0) return 0;
+   if (b == 0) return 1; // mul-by-0 is always safe
+   // portable way to check for no overflows in a*b
+   return a <= INT_MAX/b;
+}
+
+// returns 1 if "a*b + add" has no negative terms/factors and doesn't overflow
+static int stbi__mad2sizes_valid(int a, int b, int add)
+{
+   return stbi__mul2sizes_valid(a, b) && stbi__addsizes_valid(a*b, add);
+}
+
+// returns 1 if "a*b*c + add" has no negative terms/factors and doesn't overflow
+static int stbi__mad3sizes_valid(int a, int b, int c, int add)
+{
+   return stbi__mul2sizes_valid(a, b) && stbi__mul2sizes_valid(a*b, c) &&
+      stbi__addsizes_valid(a*b*c, add);
+}
+
+// returns 1 if "a*b*c*d + add" has no negative terms/factors and doesn't overflow
+#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
+static int stbi__mad4sizes_valid(int a, int b, int c, int d, int add)
+{
+   return stbi__mul2sizes_valid(a, b) && stbi__mul2sizes_valid(a*b, c) &&
+      stbi__mul2sizes_valid(a*b*c, d) && stbi__addsizes_valid(a*b*c*d, add);
+}
+#endif
+
+// mallocs with size overflow checking
+static void *stbi__malloc_mad2(int a, int b, int add)
+{
+   if (!stbi__mad2sizes_valid(a, b, add)) return NULL;
+   return stbi__malloc(a*b + add);
+}
+
+static void *stbi__malloc_mad3(int a, int b, int c, int add)
+{
+   if (!stbi__mad3sizes_valid(a, b, c, add)) return NULL;
+   return stbi__malloc(a*b*c + add);
+}
+
+#if !defined(STBI_NO_LINEAR) || !defined(STBI_NO_HDR)
+static void *stbi__malloc_mad4(int a, int b, int c, int d, int add)
+{
+   if (!stbi__mad4sizes_valid(a, b, c, d, add)) return NULL;
+   return stbi__malloc(a*b*c*d + add);
+}
+#endif
+
+// stbi__err - error
+// stbi__errpf - error returning pointer to float
+// stbi__errpuc - error returning pointer to unsigned char
+
+#ifdef STBI_NO_FAILURE_STRINGS
+   #define stbi__err(x,y)  0
+#elif defined(STBI_FAILURE_USERMSG)
+   #define stbi__err(x,y)  stbi__err(y)
+#else
+   #define stbi__err(x,y)  stbi__err(x)
+#endif
+
+#define stbi__errpf(x,y)   ((float *)(size_t) (stbi__err(x,y)?NULL:NULL))
+#define stbi__errpuc(x,y)  ((unsigned char *)(size_t) (stbi__err(x,y)?NULL:NULL))
+
+STBIDEF void stbi_image_free(void *retval_from_stbi_load)
+{
+   STBI_FREE(retval_from_stbi_load);
+}
+
+#ifndef STBI_NO_LINEAR
+static float   *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp);
+#endif
+
+#ifndef STBI_NO_HDR
+static stbi_uc *stbi__hdr_to_ldr(float   *data, int x, int y, int comp);
+#endif
+
+static int stbi__vertically_flip_on_load = 0;
+
+STBIDEF void stbi_set_flip_vertically_on_load(int flag_true_if_should_flip)
+{
+    stbi__vertically_flip_on_load = flag_true_if_should_flip;
+}
+
+static void *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc)
+{
+   memset(ri, 0, sizeof(*ri)); // make sure it's initialized if we add new fields
+   ri->bits_per_channel = 8; // default is 8 so most paths don't have to be changed
+   ri->channel_order = STBI_ORDER_RGB; // all current input & output are this, but this is here so we can add BGR order
+   ri->num_channels = 0;
+
+   #ifndef STBI_NO_JPEG
+   if (stbi__jpeg_test(s)) return stbi__jpeg_load(s,x,y,comp,req_comp, ri);
+   #endif
+   #ifndef STBI_NO_PNG
+   if (stbi__png_test(s))  return stbi__png_load(s,x,y,comp,req_comp, ri);
+   #endif
+   #ifndef STBI_NO_BMP
+   if (stbi__bmp_test(s))  return stbi__bmp_load(s,x,y,comp,req_comp, ri);
+   #endif
+   #ifndef STBI_NO_GIF
+   if (stbi__gif_test(s))  return stbi__gif_load(s,x,y,comp,req_comp, ri);
+   #endif
+   #ifndef STBI_NO_PSD
+   if (stbi__psd_test(s))  return stbi__psd_load(s,x,y,comp,req_comp, ri, bpc);
+   #endif
+   #ifndef STBI_NO_PIC
+   if (stbi__pic_test(s))  return stbi__pic_load(s,x,y,comp,req_comp, ri);
+   #endif
+   #ifndef STBI_NO_PNM
+   if (stbi__pnm_test(s))  return stbi__pnm_load(s,x,y,comp,req_comp, ri);
+   #endif
+
+   #ifndef STBI_NO_HDR
+   if (stbi__hdr_test(s)) {
+      float *hdr = stbi__hdr_load(s, x,y,comp,req_comp, ri);
+      return stbi__hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
+   }
+   #endif
+
+   #ifndef STBI_NO_TGA
+   // test tga last because it's a crappy test!
+   if (stbi__tga_test(s))
+      return stbi__tga_load(s,x,y,comp,req_comp, ri);
+   #endif
+
+   return stbi__errpuc("unknown image type", "Image not of any known type, or corrupt");
+}
+
+static stbi_uc *stbi__convert_16_to_8(stbi__uint16 *orig, int w, int h, int channels)
+{
+   int i;
+   int img_len = w * h * channels;
+   stbi_uc *reduced;
+
+   reduced = (stbi_uc *) stbi__malloc(img_len);
+   if (reduced == NULL) return stbi__errpuc("outofmem", "Out of memory");
+
+   for (i = 0; i < img_len; ++i)
+      reduced[i] = (stbi_uc)((orig[i] >> 8) & 0xFF); // top half of each byte is sufficient approx of 16->8 bit scaling
+
+   STBI_FREE(orig);
+   return reduced;
+}
+
+static stbi__uint16 *stbi__convert_8_to_16(stbi_uc *orig, int w, int h, int channels)
+{
+   int i;
+   int img_len = w * h * channels;
+   stbi__uint16 *enlarged;
+
+   enlarged = (stbi__uint16 *) stbi__malloc(img_len*2);
+   if (enlarged == NULL) return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory");
+
+   for (i = 0; i < img_len; ++i)
+      enlarged[i] = (stbi__uint16)((orig[i] << 8) + orig[i]); // replicate to high and low byte, maps 0->0, 255->0xffff
+
+   STBI_FREE(orig);
+   return enlarged;
+}
+
+static void stbi__vertical_flip(void *image, int w, int h, int bytes_per_pixel)
+{
+   int row;
+   size_t bytes_per_row = (size_t)w * bytes_per_pixel;
+   stbi_uc temp[2048];
+   stbi_uc *bytes = (stbi_uc *)image;
+
+   for (row = 0; row < (h>>1); row++) {
+      stbi_uc *row0 = bytes + row*bytes_per_row;
+      stbi_uc *row1 = bytes + (h - row - 1)*bytes_per_row;
+      // swap row0 with row1
+      size_t bytes_left = bytes_per_row;
+      while (bytes_left) {
+         size_t bytes_copy = (bytes_left < sizeof(temp)) ? bytes_left : sizeof(temp);
+         memcpy(temp, row0, bytes_copy);
+         memcpy(row0, row1, bytes_copy);
+         memcpy(row1, temp, bytes_copy);
+         row0 += bytes_copy;
+         row1 += bytes_copy;
+         bytes_left -= bytes_copy;
+      }
+   }
+}
+
+#ifndef STBI_NO_GIF
+static void stbi__vertical_flip_slices(void *image, int w, int h, int z, int bytes_per_pixel)
+{
+   int slice;
+   int slice_size = w * h * bytes_per_pixel;
+
+   stbi_uc *bytes = (stbi_uc *)image;
+   for (slice = 0; slice < z; ++slice) {
+      stbi__vertical_flip(bytes, w, h, bytes_per_pixel); 
+      bytes += slice_size; 
+   }
+}
+#endif
+
+static unsigned char *stbi__load_and_postprocess_8bit(stbi__context *s, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__result_info ri;
+   void *result = stbi__load_main(s, x, y, comp, req_comp, &ri, 8);
+
+   if (result == NULL)
+      return NULL;
+
+   if (ri.bits_per_channel != 8) {
+      STBI_ASSERT(ri.bits_per_channel == 16);
+      result = stbi__convert_16_to_8((stbi__uint16 *) result, *x, *y, req_comp == 0 ? *comp : req_comp);
+      ri.bits_per_channel = 8;
+   }
+
+   // @TODO: move stbi__convert_format to here
+
+   if (stbi__vertically_flip_on_load) {
+      int channels = req_comp ? req_comp : *comp;
+      stbi__vertical_flip(result, *x, *y, channels * sizeof(stbi_uc));
+   }
+
+   return (unsigned char *) result;
+}
+
+static stbi__uint16 *stbi__load_and_postprocess_16bit(stbi__context *s, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__result_info ri;
+   void *result = stbi__load_main(s, x, y, comp, req_comp, &ri, 16);
+
+   if (result == NULL)
+      return NULL;
+
+   if (ri.bits_per_channel != 16) {
+      STBI_ASSERT(ri.bits_per_channel == 8);
+      result = stbi__convert_8_to_16((stbi_uc *) result, *x, *y, req_comp == 0 ? *comp : req_comp);
+      ri.bits_per_channel = 16;
+   }
+
+   // @TODO: move stbi__convert_format16 to here
+   // @TODO: special case RGB-to-Y (and RGBA-to-YA) for 8-bit-to-16-bit case to keep more precision
+
+   if (stbi__vertically_flip_on_load) {
+      int channels = req_comp ? req_comp : *comp;
+      stbi__vertical_flip(result, *x, *y, channels * sizeof(stbi__uint16));
+   }
+
+   return (stbi__uint16 *) result;
+}
+
+#if !defined(STBI_NO_HDR) && !defined(STBI_NO_LINEAR)
+static void stbi__float_postprocess(float *result, int *x, int *y, int *comp, int req_comp)
+{
+   if (stbi__vertically_flip_on_load && result != NULL) {
+      int channels = req_comp ? req_comp : *comp;
+      stbi__vertical_flip(result, *x, *y, channels * sizeof(float));
+   }
+}
+#endif
+
+#ifndef STBI_NO_STDIO
+
+#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+STBI_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide);
+STBI_EXTERN __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int cp, unsigned long flags, const wchar_t *widestr, int cchwide, char *str, int cbmb, const char *defchar, int *used_default);
+#endif
+
+#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input)
+{
+	return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, bufferlen, NULL, NULL);
+}
+#endif
+
+static FILE *stbi__fopen(char const *filename, char const *mode)
+{
+   FILE *f;
+#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+   wchar_t wMode[64];
+   wchar_t wFilename[1024];
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)))
+      return 0;
+	
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)))
+      return 0;
+
+#if _MSC_VER >= 1400
+	if (0 != _wfopen_s(&f, wFilename, wMode))
+		f = 0;
+#else
+   f = _wfopen(wFilename, wMode);
+#endif
+
+#elif defined(_MSC_VER) && _MSC_VER >= 1400
+   if (0 != fopen_s(&f, filename, mode))
+      f=0;
+#else
+   f = fopen(filename, mode);
+#endif
+   return f;
+}
+
+
+STBIDEF stbi_uc *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp)
+{
+   FILE *f = stbi__fopen(filename, "rb");
+   unsigned char *result;
+   if (!f) return stbi__errpuc("can't fopen", "Unable to open file");
+   result = stbi_load_from_file(f,x,y,comp,req_comp);
+   fclose(f);
+   return result;
+}
+
+STBIDEF stbi_uc *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
+{
+   unsigned char *result;
+   stbi__context s;
+   stbi__start_file(&s,f);
+   result = stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp);
+   if (result) {
+      // need to 'unget' all the characters in the IO buffer
+      fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR);
+   }
+   return result;
+}
+
+STBIDEF stbi__uint16 *stbi_load_from_file_16(FILE *f, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__uint16 *result;
+   stbi__context s;
+   stbi__start_file(&s,f);
+   result = stbi__load_and_postprocess_16bit(&s,x,y,comp,req_comp);
+   if (result) {
+      // need to 'unget' all the characters in the IO buffer
+      fseek(f, - (int) (s.img_buffer_end - s.img_buffer), SEEK_CUR);
+   }
+   return result;
+}
+
+STBIDEF stbi_us *stbi_load_16(char const *filename, int *x, int *y, int *comp, int req_comp)
+{
+   FILE *f = stbi__fopen(filename, "rb");
+   stbi__uint16 *result;
+   if (!f) return (stbi_us *) stbi__errpuc("can't fopen", "Unable to open file");
+   result = stbi_load_from_file_16(f,x,y,comp,req_comp);
+   fclose(f);
+   return result;
+}
+
+
+#endif //!STBI_NO_STDIO
+
+STBIDEF stbi_us *stbi_load_16_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *channels_in_file, int desired_channels)
+{
+   stbi__context s;
+   stbi__start_mem(&s,buffer,len);
+   return stbi__load_and_postprocess_16bit(&s,x,y,channels_in_file,desired_channels);
+}
+
+STBIDEF stbi_us *stbi_load_16_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *channels_in_file, int desired_channels)
+{
+   stbi__context s;
+   stbi__start_callbacks(&s, (stbi_io_callbacks *)clbk, user);
+   return stbi__load_and_postprocess_16bit(&s,x,y,channels_in_file,desired_channels);
+}
+
+STBIDEF stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__context s;
+   stbi__start_mem(&s,buffer,len);
+   return stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp);
+}
+
+STBIDEF stbi_uc *stbi_load_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__context s;
+   stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
+   return stbi__load_and_postprocess_8bit(&s,x,y,comp,req_comp);
+}
+
+#ifndef STBI_NO_GIF
+STBIDEF stbi_uc *stbi_load_gif_from_memory(stbi_uc const *buffer, int len, int **delays, int *x, int *y, int *z, int *comp, int req_comp)
+{
+   unsigned char *result;
+   stbi__context s; 
+   stbi__start_mem(&s,buffer,len); 
+   
+   result = (unsigned char*) stbi__load_gif_main(&s, delays, x, y, z, comp, req_comp);
+   if (stbi__vertically_flip_on_load) {
+      stbi__vertical_flip_slices( result, *x, *y, *z, *comp ); 
+   }
+
+   return result; 
+}
+#endif
+
+#ifndef STBI_NO_LINEAR
+static float *stbi__loadf_main(stbi__context *s, int *x, int *y, int *comp, int req_comp)
+{
+   unsigned char *data;
+   #ifndef STBI_NO_HDR
+   if (stbi__hdr_test(s)) {
+      stbi__result_info ri;
+      float *hdr_data = stbi__hdr_load(s,x,y,comp,req_comp, &ri);
+      if (hdr_data)
+         stbi__float_postprocess(hdr_data,x,y,comp,req_comp);
+      return hdr_data;
+   }
+   #endif
+   data = stbi__load_and_postprocess_8bit(s, x, y, comp, req_comp);
+   if (data)
+      return stbi__ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
+   return stbi__errpf("unknown image type", "Image not of any known type, or corrupt");
+}
+
+STBIDEF float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__context s;
+   stbi__start_mem(&s,buffer,len);
+   return stbi__loadf_main(&s,x,y,comp,req_comp);
+}
+
+STBIDEF float *stbi_loadf_from_callbacks(stbi_io_callbacks const *clbk, void *user, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__context s;
+   stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
+   return stbi__loadf_main(&s,x,y,comp,req_comp);
+}
+
+#ifndef STBI_NO_STDIO
+STBIDEF float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp)
+{
+   float *result;
+   FILE *f = stbi__fopen(filename, "rb");
+   if (!f) return stbi__errpf("can't fopen", "Unable to open file");
+   result = stbi_loadf_from_file(f,x,y,comp,req_comp);
+   fclose(f);
+   return result;
+}
+
+STBIDEF float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
+{
+   stbi__context s;
+   stbi__start_file(&s,f);
+   return stbi__loadf_main(&s,x,y,comp,req_comp);
+}
+#endif // !STBI_NO_STDIO
+
+#endif // !STBI_NO_LINEAR
+
+// these is-hdr-or-not is defined independent of whether STBI_NO_LINEAR is
+// defined, for API simplicity; if STBI_NO_LINEAR is defined, it always
+// reports false!
+
+STBIDEF int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len)
+{
+   #ifndef STBI_NO_HDR
+   stbi__context s;
+   stbi__start_mem(&s,buffer,len);
+   return stbi__hdr_test(&s);
+   #else
+   STBI_NOTUSED(buffer);
+   STBI_NOTUSED(len);
+   return 0;
+   #endif
+}
+
+#ifndef STBI_NO_STDIO
+STBIDEF int      stbi_is_hdr          (char const *filename)
+{
+   FILE *f = stbi__fopen(filename, "rb");
+   int result=0;
+   if (f) {
+      result = stbi_is_hdr_from_file(f);
+      fclose(f);
+   }
+   return result;
+}
+
+STBIDEF int stbi_is_hdr_from_file(FILE *f)
+{
+   #ifndef STBI_NO_HDR
+   long pos = ftell(f);
+   int res;
+   stbi__context s;
+   stbi__start_file(&s,f);
+   res = stbi__hdr_test(&s);
+   fseek(f, pos, SEEK_SET);
+   return res;
+   #else
+   STBI_NOTUSED(f);
+   return 0;
+   #endif
+}
+#endif // !STBI_NO_STDIO
+
+STBIDEF int      stbi_is_hdr_from_callbacks(stbi_io_callbacks const *clbk, void *user)
+{
+   #ifndef STBI_NO_HDR
+   stbi__context s;
+   stbi__start_callbacks(&s, (stbi_io_callbacks *) clbk, user);
+   return stbi__hdr_test(&s);
+   #else
+   STBI_NOTUSED(clbk);
+   STBI_NOTUSED(user);
+   return 0;
+   #endif
+}
+
+#ifndef STBI_NO_LINEAR
+static float stbi__l2h_gamma=2.2f, stbi__l2h_scale=1.0f;
+
+STBIDEF void   stbi_ldr_to_hdr_gamma(float gamma) { stbi__l2h_gamma = gamma; }
+STBIDEF void   stbi_ldr_to_hdr_scale(float scale) { stbi__l2h_scale = scale; }
+#endif
+
+static float stbi__h2l_gamma_i=1.0f/2.2f, stbi__h2l_scale_i=1.0f;
+
+STBIDEF void   stbi_hdr_to_ldr_gamma(float gamma) { stbi__h2l_gamma_i = 1/gamma; }
+STBIDEF void   stbi_hdr_to_ldr_scale(float scale) { stbi__h2l_scale_i = 1/scale; }
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Common code used by all image loaders
+//
+
+enum
+{
+   STBI__SCAN_load=0,
+   STBI__SCAN_type,
+   STBI__SCAN_header
+};
+
+static void stbi__refill_buffer(stbi__context *s)
+{
+   int n = (s->io.read)(s->io_user_data,(char*)s->buffer_start,s->buflen);
+   if (n == 0) {
+      // at end of file, treat same as if from memory, but need to handle case
+      // where s->img_buffer isn't pointing to safe memory, e.g. 0-byte file
+      s->read_from_callbacks = 0;
+      s->img_buffer = s->buffer_start;
+      s->img_buffer_end = s->buffer_start+1;
+      *s->img_buffer = 0;
+   } else {
+      s->img_buffer = s->buffer_start;
+      s->img_buffer_end = s->buffer_start + n;
+   }
+}
+
+stbi_inline static stbi_uc stbi__get8(stbi__context *s)
+{
+   if (s->img_buffer < s->img_buffer_end)
+      return *s->img_buffer++;
+   if (s->read_from_callbacks) {
+      stbi__refill_buffer(s);
+      return *s->img_buffer++;
+   }
+   return 0;
+}
+
+stbi_inline static int stbi__at_eof(stbi__context *s)
+{
+   if (s->io.read) {
+      if (!(s->io.eof)(s->io_user_data)) return 0;
+      // if feof() is true, check if buffer = end
+      // special case: we've only got the special 0 character at the end
+      if (s->read_from_callbacks == 0) return 1;
+   }
+
+   return s->img_buffer >= s->img_buffer_end;
+}
+
+static void stbi__skip(stbi__context *s, int n)
+{
+   if (n < 0) {
+      s->img_buffer = s->img_buffer_end;
+      return;
+   }
+   if (s->io.read) {
+      int blen = (int) (s->img_buffer_end - s->img_buffer);
+      if (blen < n) {
+         s->img_buffer = s->img_buffer_end;
+         (s->io.skip)(s->io_user_data, n - blen);
+         return;
+      }
+   }
+   s->img_buffer += n;
+}
+
+static int stbi__getn(stbi__context *s, stbi_uc *buffer, int n)
+{
+   if (s->io.read) {
+      int blen = (int) (s->img_buffer_end - s->img_buffer);
+      if (blen < n) {
+         int res, count;
+
+         memcpy(buffer, s->img_buffer, blen);
+
+         count = (s->io.read)(s->io_user_data, (char*) buffer + blen, n - blen);
+         res = (count == (n-blen));
+         s->img_buffer = s->img_buffer_end;
+         return res;
+      }
+   }
+
+   if (s->img_buffer+n <= s->img_buffer_end) {
+      memcpy(buffer, s->img_buffer, n);
+      s->img_buffer += n;
+      return 1;
+   } else
+      return 0;
+}
+
+static int stbi__get16be(stbi__context *s)
+{
+   int z = stbi__get8(s);
+   return (z << 8) + stbi__get8(s);
+}
+
+static stbi__uint32 stbi__get32be(stbi__context *s)
+{
+   stbi__uint32 z = stbi__get16be(s);
+   return (z << 16) + stbi__get16be(s);
+}
+
+#if defined(STBI_NO_BMP) && defined(STBI_NO_TGA) && defined(STBI_NO_GIF)
+// nothing
+#else
+static int stbi__get16le(stbi__context *s)
+{
+   int z = stbi__get8(s);
+   return z + (stbi__get8(s) << 8);
+}
+#endif
+
+#ifndef STBI_NO_BMP
+static stbi__uint32 stbi__get32le(stbi__context *s)
+{
+   stbi__uint32 z = stbi__get16le(s);
+   return z + (stbi__get16le(s) << 16);
+}
+#endif
+
+#define STBI__BYTECAST(x)  ((stbi_uc) ((x) & 255))  // truncate int to byte without warnings
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//  generic converter from built-in img_n to req_comp
+//    individual types do this automatically as much as possible (e.g. jpeg
+//    does all cases internally since it needs to colorspace convert anyway,
+//    and it never has alpha, so very few cases ). png can automatically
+//    interleave an alpha=255 channel, but falls back to this for other cases
+//
+//  assume data buffer is malloced, so malloc a new one and free that one
+//  only failure mode is malloc failing
+
+static stbi_uc stbi__compute_y(int r, int g, int b)
+{
+   return (stbi_uc) (((r*77) + (g*150) +  (29*b)) >> 8);
+}
+
+static unsigned char *stbi__convert_format(unsigned char *data, int img_n, int req_comp, unsigned int x, unsigned int y)
+{
+   int i,j;
+   unsigned char *good;
+
+   if (req_comp == img_n) return data;
+   STBI_ASSERT(req_comp >= 1 && req_comp <= 4);
+
+   good = (unsigned char *) stbi__malloc_mad3(req_comp, x, y, 0);
+   if (good == NULL) {
+      STBI_FREE(data);
+      return stbi__errpuc("outofmem", "Out of memory");
+   }
+
+   for (j=0; j < (int) y; ++j) {
+      unsigned char *src  = data + j * x * img_n   ;
+      unsigned char *dest = good + j * x * req_comp;
+
+      #define STBI__COMBO(a,b)  ((a)*8+(b))
+      #define STBI__CASE(a,b)   case STBI__COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
+      // convert source image with img_n components to one with req_comp components;
+      // avoid switch per pixel, so use switch per scanline and massive macros
+      switch (STBI__COMBO(img_n, req_comp)) {
+         STBI__CASE(1,2) { dest[0]=src[0]; dest[1]=255;                                     } break;
+         STBI__CASE(1,3) { dest[0]=dest[1]=dest[2]=src[0];                                  } break;
+         STBI__CASE(1,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=255;                     } break;
+         STBI__CASE(2,1) { dest[0]=src[0];                                                  } break;
+         STBI__CASE(2,3) { dest[0]=dest[1]=dest[2]=src[0];                                  } break;
+         STBI__CASE(2,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=src[1];                  } break;
+         STBI__CASE(3,4) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];dest[3]=255;        } break;
+         STBI__CASE(3,1) { dest[0]=stbi__compute_y(src[0],src[1],src[2]);                   } break;
+         STBI__CASE(3,2) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); dest[1] = 255;    } break;
+         STBI__CASE(4,1) { dest[0]=stbi__compute_y(src[0],src[1],src[2]);                   } break;
+         STBI__CASE(4,2) { dest[0]=stbi__compute_y(src[0],src[1],src[2]); dest[1] = src[3]; } break;
+         STBI__CASE(4,3) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];                    } break;
+         default: STBI_ASSERT(0);
+      }
+      #undef STBI__CASE
+   }
+
+   STBI_FREE(data);
+   return good;
+}
+
+static stbi__uint16 stbi__compute_y_16(int r, int g, int b)
+{
+   return (stbi__uint16) (((r*77) + (g*150) +  (29*b)) >> 8);
+}
+
+static stbi__uint16 *stbi__convert_format16(stbi__uint16 *data, int img_n, int req_comp, unsigned int x, unsigned int y)
+{
+   int i,j;
+   stbi__uint16 *good;
+
+   if (req_comp == img_n) return data;
+   STBI_ASSERT(req_comp >= 1 && req_comp <= 4);
+
+   good = (stbi__uint16 *) stbi__malloc(req_comp * x * y * 2);
+   if (good == NULL) {
+      STBI_FREE(data);
+      return (stbi__uint16 *) stbi__errpuc("outofmem", "Out of memory");
+   }
+
+   for (j=0; j < (int) y; ++j) {
+      stbi__uint16 *src  = data + j * x * img_n   ;
+      stbi__uint16 *dest = good + j * x * req_comp;
+
+      #define STBI__COMBO(a,b)  ((a)*8+(b))
+      #define STBI__CASE(a,b)   case STBI__COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
+      // convert source image with img_n components to one with req_comp components;
+      // avoid switch per pixel, so use switch per scanline and massive macros
+      switch (STBI__COMBO(img_n, req_comp)) {
+         STBI__CASE(1,2) { dest[0]=src[0]; dest[1]=0xffff;                                     } break;
+         STBI__CASE(1,3) { dest[0]=dest[1]=dest[2]=src[0];                                     } break;
+         STBI__CASE(1,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=0xffff;                     } break;
+         STBI__CASE(2,1) { dest[0]=src[0];                                                     } break;
+         STBI__CASE(2,3) { dest[0]=dest[1]=dest[2]=src[0];                                     } break;
+         STBI__CASE(2,4) { dest[0]=dest[1]=dest[2]=src[0]; dest[3]=src[1];                     } break;
+         STBI__CASE(3,4) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];dest[3]=0xffff;        } break;
+         STBI__CASE(3,1) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]);                   } break;
+         STBI__CASE(3,2) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); dest[1] = 0xffff; } break;
+         STBI__CASE(4,1) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]);                   } break;
+         STBI__CASE(4,2) { dest[0]=stbi__compute_y_16(src[0],src[1],src[2]); dest[1] = src[3]; } break;
+         STBI__CASE(4,3) { dest[0]=src[0];dest[1]=src[1];dest[2]=src[2];                       } break;
+         default: STBI_ASSERT(0);
+      }
+      #undef STBI__CASE
+   }
+
+   STBI_FREE(data);
+   return good;
+}
+
+#ifndef STBI_NO_LINEAR
+static float   *stbi__ldr_to_hdr(stbi_uc *data, int x, int y, int comp)
+{
+   int i,k,n;
+   float *output;
+   if (!data) return NULL;
+   output = (float *) stbi__malloc_mad4(x, y, comp, sizeof(float), 0);
+   if (output == NULL) { STBI_FREE(data); return stbi__errpf("outofmem", "Out of memory"); }
+   // compute number of non-alpha components
+   if (comp & 1) n = comp; else n = comp-1;
+   for (i=0; i < x*y; ++i) {
+      for (k=0; k < n; ++k) {
+         output[i*comp + k] = (float) (pow(data[i*comp+k]/255.0f, stbi__l2h_gamma) * stbi__l2h_scale);
+      }
+   }
+   if (n < comp) {
+      for (i=0; i < x*y; ++i) {
+         output[i*comp + n] = data[i*comp + n]/255.0f;
+      }
+   }
+   STBI_FREE(data);
+   return output;
+}
+#endif
+
+#ifndef STBI_NO_HDR
+#define stbi__float2int(x)   ((int) (x))
+static stbi_uc *stbi__hdr_to_ldr(float   *data, int x, int y, int comp)
+{
+   int i,k,n;
+   stbi_uc *output;
+   if (!data) return NULL;
+   output = (stbi_uc *) stbi__malloc_mad3(x, y, comp, 0);
+   if (output == NULL) { STBI_FREE(data); return stbi__errpuc("outofmem", "Out of memory"); }
+   // compute number of non-alpha components
+   if (comp & 1) n = comp; else n = comp-1;
+   for (i=0; i < x*y; ++i) {
+      for (k=0; k < n; ++k) {
+         float z = (float) pow(data[i*comp+k]*stbi__h2l_scale_i, stbi__h2l_gamma_i) * 255 + 0.5f;
+         if (z < 0) z = 0;
+         if (z > 255) z = 255;
+         output[i*comp + k] = (stbi_uc) stbi__float2int(z);
+      }
+      if (k < comp) {
+         float z = data[i*comp+k] * 255 + 0.5f;
+         if (z < 0) z = 0;
+         if (z > 255) z = 255;
+         output[i*comp + k] = (stbi_uc) stbi__float2int(z);
+      }
+   }
+   STBI_FREE(data);
+   return output;
+}
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//  "baseline" JPEG/JFIF decoder
+//
+//    simple implementation
+//      - doesn't support delayed output of y-dimension
+//      - simple interface (only one output format: 8-bit interleaved RGB)
+//      - doesn't try to recover corrupt jpegs
+//      - doesn't allow partial loading, loading multiple at once
+//      - still fast on x86 (copying globals into locals doesn't help x86)
+//      - allocates lots of intermediate memory (full size of all components)
+//        - non-interleaved case requires this anyway
+//        - allows good upsampling (see next)
+//    high-quality
+//      - upsampled channels are bilinearly interpolated, even across blocks
+//      - quality integer IDCT derived from IJG's 'slow'
+//    performance
+//      - fast huffman; reasonable integer IDCT
+//      - some SIMD kernels for common paths on targets with SSE2/NEON
+//      - uses a lot of intermediate memory, could cache poorly
+
+#ifndef STBI_NO_JPEG
+
+// huffman decoding acceleration
+#define FAST_BITS   9  // larger handles more cases; smaller stomps less cache
+
+typedef struct
+{
+   stbi_uc  fast[1 << FAST_BITS];
+   // weirdly, repacking this into AoS is a 10% speed loss, instead of a win
+   stbi__uint16 code[256];
+   stbi_uc  values[256];
+   stbi_uc  size[257];
+   unsigned int maxcode[18];
+   int    delta[17];   // old 'firstsymbol' - old 'firstcode'
+} stbi__huffman;
+
+typedef struct
+{
+   stbi__context *s;
+   stbi__huffman huff_dc[4];
+   stbi__huffman huff_ac[4];
+   stbi__uint16 dequant[4][64];
+   stbi__int16 fast_ac[4][1 << FAST_BITS];
+
+// sizes for components, interleaved MCUs
+   int img_h_max, img_v_max;
+   int img_mcu_x, img_mcu_y;
+   int img_mcu_w, img_mcu_h;
+
+// definition of jpeg image component
+   struct
+   {
+      int id;
+      int h,v;
+      int tq;
+      int hd,ha;
+      int dc_pred;
+
+      int x,y,w2,h2;
+      stbi_uc *data;
+      void *raw_data, *raw_coeff;
+      stbi_uc *linebuf;
+      short   *coeff;   // progressive only
+      int      coeff_w, coeff_h; // number of 8x8 coefficient blocks
+   } img_comp[4];
+
+   stbi__uint32   code_buffer; // jpeg entropy-coded buffer
+   int            code_bits;   // number of valid bits
+   unsigned char  marker;      // marker seen while filling entropy buffer
+   int            nomore;      // flag if we saw a marker so must stop
+
+   int            progressive;
+   int            spec_start;
+   int            spec_end;
+   int            succ_high;
+   int            succ_low;
+   int            eob_run;
+   int            jfif;
+   int            app14_color_transform; // Adobe APP14 tag
+   int            rgb;
+
+   int scan_n, order[4];
+   int restart_interval, todo;
+
+// kernels
+   void (*idct_block_kernel)(stbi_uc *out, int out_stride, short data[64]);
+   void (*YCbCr_to_RGB_kernel)(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step);
+   stbi_uc *(*resample_row_hv_2_kernel)(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs);
+} stbi__jpeg;
+
+static int stbi__build_huffman(stbi__huffman *h, int *count)
+{
+   int i,j,k=0;
+   unsigned int code;
+   // build size list for each symbol (from JPEG spec)
+   for (i=0; i < 16; ++i)
+      for (j=0; j < count[i]; ++j)
+         h->size[k++] = (stbi_uc) (i+1);
+   h->size[k] = 0;
+
+   // compute actual symbols (from jpeg spec)
+   code = 0;
+   k = 0;
+   for(j=1; j <= 16; ++j) {
+      // compute delta to add to code to compute symbol id
+      h->delta[j] = k - code;
+      if (h->size[k] == j) {
+         while (h->size[k] == j)
+            h->code[k++] = (stbi__uint16) (code++);
+         if (code-1 >= (1u << j)) return stbi__err("bad code lengths","Corrupt JPEG");
+      }
+      // compute largest code + 1 for this size, preshifted as needed later
+      h->maxcode[j] = code << (16-j);
+      code <<= 1;
+   }
+   h->maxcode[j] = 0xffffffff;
+
+   // build non-spec acceleration table; 255 is flag for not-accelerated
+   memset(h->fast, 255, 1 << FAST_BITS);
+   for (i=0; i < k; ++i) {
+      int s = h->size[i];
+      if (s <= FAST_BITS) {
+         int c = h->code[i] << (FAST_BITS-s);
+         int m = 1 << (FAST_BITS-s);
+         for (j=0; j < m; ++j) {
+            h->fast[c+j] = (stbi_uc) i;
+         }
+      }
+   }
+   return 1;
+}
+
+// build a table that decodes both magnitude and value of small ACs in
+// one go.
+static void stbi__build_fast_ac(stbi__int16 *fast_ac, stbi__huffman *h)
+{
+   int i;
+   for (i=0; i < (1 << FAST_BITS); ++i) {
+      stbi_uc fast = h->fast[i];
+      fast_ac[i] = 0;
+      if (fast < 255) {
+         int rs = h->values[fast];
+         int run = (rs >> 4) & 15;
+         int magbits = rs & 15;
+         int len = h->size[fast];
+
+         if (magbits && len + magbits <= FAST_BITS) {
+            // magnitude code followed by receive_extend code
+            int k = ((i << len) & ((1 << FAST_BITS) - 1)) >> (FAST_BITS - magbits);
+            int m = 1 << (magbits - 1);
+            if (k < m) k += (~0U << magbits) + 1;
+            // if the result is small enough, we can fit it in fast_ac table
+            if (k >= -128 && k <= 127)
+               fast_ac[i] = (stbi__int16) ((k * 256) + (run * 16) + (len + magbits));
+         }
+      }
+   }
+}
+
+static void stbi__grow_buffer_unsafe(stbi__jpeg *j)
+{
+   do {
+      unsigned int b = j->nomore ? 0 : stbi__get8(j->s);
+      if (b == 0xff) {
+         int c = stbi__get8(j->s);
+         while (c == 0xff) c = stbi__get8(j->s); // consume fill bytes
+         if (c != 0) {
+            j->marker = (unsigned char) c;
+            j->nomore = 1;
+            return;
+         }
+      }
+      j->code_buffer |= b << (24 - j->code_bits);
+      j->code_bits += 8;
+   } while (j->code_bits <= 24);
+}
+
+// (1 << n) - 1
+static const stbi__uint32 stbi__bmask[17]={0,1,3,7,15,31,63,127,255,511,1023,2047,4095,8191,16383,32767,65535};
+
+// decode a jpeg huffman value from the bitstream
+stbi_inline static int stbi__jpeg_huff_decode(stbi__jpeg *j, stbi__huffman *h)
+{
+   unsigned int temp;
+   int c,k;
+
+   if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
+
+   // look at the top FAST_BITS and determine what symbol ID it is,
+   // if the code is <= FAST_BITS
+   c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
+   k = h->fast[c];
+   if (k < 255) {
+      int s = h->size[k];
+      if (s > j->code_bits)
+         return -1;
+      j->code_buffer <<= s;
+      j->code_bits -= s;
+      return h->values[k];
+   }
+
+   // naive test is to shift the code_buffer down so k bits are
+   // valid, then test against maxcode. To speed this up, we've
+   // preshifted maxcode left so that it has (16-k) 0s at the
+   // end; in other words, regardless of the number of bits, it
+   // wants to be compared against something shifted to have 16;
+   // that way we don't need to shift inside the loop.
+   temp = j->code_buffer >> 16;
+   for (k=FAST_BITS+1 ; ; ++k)
+      if (temp < h->maxcode[k])
+         break;
+   if (k == 17) {
+      // error! code not found
+      j->code_bits -= 16;
+      return -1;
+   }
+
+   if (k > j->code_bits)
+      return -1;
+
+   // convert the huffman code to the symbol id
+   c = ((j->code_buffer >> (32 - k)) & stbi__bmask[k]) + h->delta[k];
+   STBI_ASSERT((((j->code_buffer) >> (32 - h->size[c])) & stbi__bmask[h->size[c]]) == h->code[c]);
+
+   // convert the id to a symbol
+   j->code_bits -= k;
+   j->code_buffer <<= k;
+   return h->values[c];
+}
+
+// bias[n] = (-1<<n) + 1
+static const int stbi__jbias[16] = {0,-1,-3,-7,-15,-31,-63,-127,-255,-511,-1023,-2047,-4095,-8191,-16383,-32767};
+
+// combined JPEG 'receive' and JPEG 'extend', since baseline
+// always extends everything it receives.
+stbi_inline static int stbi__extend_receive(stbi__jpeg *j, int n)
+{
+   unsigned int k;
+   int sgn;
+   if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
+
+   sgn = (stbi__int32)j->code_buffer >> 31; // sign bit is always in MSB
+   k = stbi_lrot(j->code_buffer, n);
+   STBI_ASSERT(n >= 0 && n < (int) (sizeof(stbi__bmask)/sizeof(*stbi__bmask)));
+   j->code_buffer = k & ~stbi__bmask[n];
+   k &= stbi__bmask[n];
+   j->code_bits -= n;
+   return k + (stbi__jbias[n] & ~sgn);
+}
+
+// get some unsigned bits
+stbi_inline static int stbi__jpeg_get_bits(stbi__jpeg *j, int n)
+{
+   unsigned int k;
+   if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
+   k = stbi_lrot(j->code_buffer, n);
+   j->code_buffer = k & ~stbi__bmask[n];
+   k &= stbi__bmask[n];
+   j->code_bits -= n;
+   return k;
+}
+
+stbi_inline static int stbi__jpeg_get_bit(stbi__jpeg *j)
+{
+   unsigned int k;
+   if (j->code_bits < 1) stbi__grow_buffer_unsafe(j);
+   k = j->code_buffer;
+   j->code_buffer <<= 1;
+   --j->code_bits;
+   return k & 0x80000000;
+}
+
+// given a value that's at position X in the zigzag stream,
+// where does it appear in the 8x8 matrix coded as row-major?
+static const stbi_uc stbi__jpeg_dezigzag[64+15] =
+{
+    0,  1,  8, 16,  9,  2,  3, 10,
+   17, 24, 32, 25, 18, 11,  4,  5,
+   12, 19, 26, 33, 40, 48, 41, 34,
+   27, 20, 13,  6,  7, 14, 21, 28,
+   35, 42, 49, 56, 57, 50, 43, 36,
+   29, 22, 15, 23, 30, 37, 44, 51,
+   58, 59, 52, 45, 38, 31, 39, 46,
+   53, 60, 61, 54, 47, 55, 62, 63,
+   // let corrupt input sample past end
+   63, 63, 63, 63, 63, 63, 63, 63,
+   63, 63, 63, 63, 63, 63, 63
+};
+
+// decode one 64-entry block--
+static int stbi__jpeg_decode_block(stbi__jpeg *j, short data[64], stbi__huffman *hdc, stbi__huffman *hac, stbi__int16 *fac, int b, stbi__uint16 *dequant)
+{
+   int diff,dc,k;
+   int t;
+
+   if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
+   t = stbi__jpeg_huff_decode(j, hdc);
+   if (t < 0) return stbi__err("bad huffman code","Corrupt JPEG");
+
+   // 0 all the ac values now so we can do it 32-bits at a time
+   memset(data,0,64*sizeof(data[0]));
+
+   diff = t ? stbi__extend_receive(j, t) : 0;
+   dc = j->img_comp[b].dc_pred + diff;
+   j->img_comp[b].dc_pred = dc;
+   data[0] = (short) (dc * dequant[0]);
+
+   // decode AC components, see JPEG spec
+   k = 1;
+   do {
+      unsigned int zig;
+      int c,r,s;
+      if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
+      c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
+      r = fac[c];
+      if (r) { // fast-AC path
+         k += (r >> 4) & 15; // run
+         s = r & 15; // combined length
+         j->code_buffer <<= s;
+         j->code_bits -= s;
+         // decode into unzigzag'd location
+         zig = stbi__jpeg_dezigzag[k++];
+         data[zig] = (short) ((r >> 8) * dequant[zig]);
+      } else {
+         int rs = stbi__jpeg_huff_decode(j, hac);
+         if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
+         s = rs & 15;
+         r = rs >> 4;
+         if (s == 0) {
+            if (rs != 0xf0) break; // end block
+            k += 16;
+         } else {
+            k += r;
+            // decode into unzigzag'd location
+            zig = stbi__jpeg_dezigzag[k++];
+            data[zig] = (short) (stbi__extend_receive(j,s) * dequant[zig]);
+         }
+      }
+   } while (k < 64);
+   return 1;
+}
+
+static int stbi__jpeg_decode_block_prog_dc(stbi__jpeg *j, short data[64], stbi__huffman *hdc, int b)
+{
+   int diff,dc;
+   int t;
+   if (j->spec_end != 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
+
+   if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
+
+   if (j->succ_high == 0) {
+      // first scan for DC coefficient, must be first
+      memset(data,0,64*sizeof(data[0])); // 0 all the ac values now
+      t = stbi__jpeg_huff_decode(j, hdc);
+      diff = t ? stbi__extend_receive(j, t) : 0;
+
+      dc = j->img_comp[b].dc_pred + diff;
+      j->img_comp[b].dc_pred = dc;
+      data[0] = (short) (dc << j->succ_low);
+   } else {
+      // refinement scan for DC coefficient
+      if (stbi__jpeg_get_bit(j))
+         data[0] += (short) (1 << j->succ_low);
+   }
+   return 1;
+}
+
+// @OPTIMIZE: store non-zigzagged during the decode passes,
+// and only de-zigzag when dequantizing
+static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__huffman *hac, stbi__int16 *fac)
+{
+   int k;
+   if (j->spec_start == 0) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
+
+   if (j->succ_high == 0) {
+      int shift = j->succ_low;
+
+      if (j->eob_run) {
+         --j->eob_run;
+         return 1;
+      }
+
+      k = j->spec_start;
+      do {
+         unsigned int zig;
+         int c,r,s;
+         if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
+         c = (j->code_buffer >> (32 - FAST_BITS)) & ((1 << FAST_BITS)-1);
+         r = fac[c];
+         if (r) { // fast-AC path
+            k += (r >> 4) & 15; // run
+            s = r & 15; // combined length
+            j->code_buffer <<= s;
+            j->code_bits -= s;
+            zig = stbi__jpeg_dezigzag[k++];
+            data[zig] = (short) ((r >> 8) << shift);
+         } else {
+            int rs = stbi__jpeg_huff_decode(j, hac);
+            if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
+            s = rs & 15;
+            r = rs >> 4;
+            if (s == 0) {
+               if (r < 15) {
+                  j->eob_run = (1 << r);
+                  if (r)
+                     j->eob_run += stbi__jpeg_get_bits(j, r);
+                  --j->eob_run;
+                  break;
+               }
+               k += 16;
+            } else {
+               k += r;
+               zig = stbi__jpeg_dezigzag[k++];
+               data[zig] = (short) (stbi__extend_receive(j,s) << shift);
+            }
+         }
+      } while (k <= j->spec_end);
+   } else {
+      // refinement scan for these AC coefficients
+
+      short bit = (short) (1 << j->succ_low);
+
+      if (j->eob_run) {
+         --j->eob_run;
+         for (k = j->spec_start; k <= j->spec_end; ++k) {
+            short *p = &data[stbi__jpeg_dezigzag[k]];
+            if (*p != 0)
+               if (stbi__jpeg_get_bit(j))
+                  if ((*p & bit)==0) {
+                     if (*p > 0)
+                        *p += bit;
+                     else
+                        *p -= bit;
+                  }
+         }
+      } else {
+         k = j->spec_start;
+         do {
+            int r,s;
+            int rs = stbi__jpeg_huff_decode(j, hac); // @OPTIMIZE see if we can use the fast path here, advance-by-r is so slow, eh
+            if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
+            s = rs & 15;
+            r = rs >> 4;
+            if (s == 0) {
+               if (r < 15) {
+                  j->eob_run = (1 << r) - 1;
+                  if (r)
+                     j->eob_run += stbi__jpeg_get_bits(j, r);
+                  r = 64; // force end of block
+               } else {
+                  // r=15 s=0 should write 16 0s, so we just do
+                  // a run of 15 0s and then write s (which is 0),
+                  // so we don't have to do anything special here
+               }
+            } else {
+               if (s != 1) return stbi__err("bad huffman code", "Corrupt JPEG");
+               // sign bit
+               if (stbi__jpeg_get_bit(j))
+                  s = bit;
+               else
+                  s = -bit;
+            }
+
+            // advance by r
+            while (k <= j->spec_end) {
+               short *p = &data[stbi__jpeg_dezigzag[k++]];
+               if (*p != 0) {
+                  if (stbi__jpeg_get_bit(j))
+                     if ((*p & bit)==0) {
+                        if (*p > 0)
+                           *p += bit;
+                        else
+                           *p -= bit;
+                     }
+               } else {
+                  if (r == 0) {
+                     *p = (short) s;
+                     break;
+                  }
+                  --r;
+               }
+            }
+         } while (k <= j->spec_end);
+      }
+   }
+   return 1;
+}
+
+// take a -128..127 value and stbi__clamp it and convert to 0..255
+stbi_inline static stbi_uc stbi__clamp(int x)
+{
+   // trick to use a single test to catch both cases
+   if ((unsigned int) x > 255) {
+      if (x < 0) return 0;
+      if (x > 255) return 255;
+   }
+   return (stbi_uc) x;
+}
+
+#define stbi__f2f(x)  ((int) (((x) * 4096 + 0.5)))
+#define stbi__fsh(x)  ((x) * 4096)
+
+// derived from jidctint -- DCT_ISLOW
+#define STBI__IDCT_1D(s0,s1,s2,s3,s4,s5,s6,s7) \
+   int t0,t1,t2,t3,p1,p2,p3,p4,p5,x0,x1,x2,x3; \
+   p2 = s2;                                    \
+   p3 = s6;                                    \
+   p1 = (p2+p3) * stbi__f2f(0.5411961f);       \
+   t2 = p1 + p3*stbi__f2f(-1.847759065f);      \
+   t3 = p1 + p2*stbi__f2f( 0.765366865f);      \
+   p2 = s0;                                    \
+   p3 = s4;                                    \
+   t0 = stbi__fsh(p2+p3);                      \
+   t1 = stbi__fsh(p2-p3);                      \
+   x0 = t0+t3;                                 \
+   x3 = t0-t3;                                 \
+   x1 = t1+t2;                                 \
+   x2 = t1-t2;                                 \
+   t0 = s7;                                    \
+   t1 = s5;                                    \
+   t2 = s3;                                    \
+   t3 = s1;                                    \
+   p3 = t0+t2;                                 \
+   p4 = t1+t3;                                 \
+   p1 = t0+t3;                                 \
+   p2 = t1+t2;                                 \
+   p5 = (p3+p4)*stbi__f2f( 1.175875602f);      \
+   t0 = t0*stbi__f2f( 0.298631336f);           \
+   t1 = t1*stbi__f2f( 2.053119869f);           \
+   t2 = t2*stbi__f2f( 3.072711026f);           \
+   t3 = t3*stbi__f2f( 1.501321110f);           \
+   p1 = p5 + p1*stbi__f2f(-0.899976223f);      \
+   p2 = p5 + p2*stbi__f2f(-2.562915447f);      \
+   p3 = p3*stbi__f2f(-1.961570560f);           \
+   p4 = p4*stbi__f2f(-0.390180644f);           \
+   t3 += p1+p4;                                \
+   t2 += p2+p3;                                \
+   t1 += p2+p4;                                \
+   t0 += p1+p3;
+
+static void stbi__idct_block(stbi_uc *out, int out_stride, short data[64])
+{
+   int i,val[64],*v=val;
+   stbi_uc *o;
+   short *d = data;
+
+   // columns
+   for (i=0; i < 8; ++i,++d, ++v) {
+      // if all zeroes, shortcut -- this avoids dequantizing 0s and IDCTing
+      if (d[ 8]==0 && d[16]==0 && d[24]==0 && d[32]==0
+           && d[40]==0 && d[48]==0 && d[56]==0) {
+         //    no shortcut                 0     seconds
+         //    (1|2|3|4|5|6|7)==0          0     seconds
+         //    all separate               -0.047 seconds
+         //    1 && 2|3 && 4|5 && 6|7:    -0.047 seconds
+         int dcterm = d[0]*4;
+         v[0] = v[8] = v[16] = v[24] = v[32] = v[40] = v[48] = v[56] = dcterm;
+      } else {
+         STBI__IDCT_1D(d[ 0],d[ 8],d[16],d[24],d[32],d[40],d[48],d[56])
+         // constants scaled things up by 1<<12; let's bring them back
+         // down, but keep 2 extra bits of precision
+         x0 += 512; x1 += 512; x2 += 512; x3 += 512;
+         v[ 0] = (x0+t3) >> 10;
+         v[56] = (x0-t3) >> 10;
+         v[ 8] = (x1+t2) >> 10;
+         v[48] = (x1-t2) >> 10;
+         v[16] = (x2+t1) >> 10;
+         v[40] = (x2-t1) >> 10;
+         v[24] = (x3+t0) >> 10;
+         v[32] = (x3-t0) >> 10;
+      }
+   }
+
+   for (i=0, v=val, o=out; i < 8; ++i,v+=8,o+=out_stride) {
+      // no fast case since the first 1D IDCT spread components out
+      STBI__IDCT_1D(v[0],v[1],v[2],v[3],v[4],v[5],v[6],v[7])
+      // constants scaled things up by 1<<12, plus we had 1<<2 from first
+      // loop, plus horizontal and vertical each scale by sqrt(8) so together
+      // we've got an extra 1<<3, so 1<<17 total we need to remove.
+      // so we want to round that, which means adding 0.5 * 1<<17,
+      // aka 65536. Also, we'll end up with -128 to 127 that we want
+      // to encode as 0..255 by adding 128, so we'll add that before the shift
+      x0 += 65536 + (128<<17);
+      x1 += 65536 + (128<<17);
+      x2 += 65536 + (128<<17);
+      x3 += 65536 + (128<<17);
+      // tried computing the shifts into temps, or'ing the temps to see
+      // if any were out of range, but that was slower
+      o[0] = stbi__clamp((x0+t3) >> 17);
+      o[7] = stbi__clamp((x0-t3) >> 17);
+      o[1] = stbi__clamp((x1+t2) >> 17);
+      o[6] = stbi__clamp((x1-t2) >> 17);
+      o[2] = stbi__clamp((x2+t1) >> 17);
+      o[5] = stbi__clamp((x2-t1) >> 17);
+      o[3] = stbi__clamp((x3+t0) >> 17);
+      o[4] = stbi__clamp((x3-t0) >> 17);
+   }
+}
+
+#ifdef STBI_SSE2
+// sse2 integer IDCT. not the fastest possible implementation but it
+// produces bit-identical results to the generic C version so it's
+// fully "transparent".
+static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64])
+{
+   // This is constructed to match our regular (generic) integer IDCT exactly.
+   __m128i row0, row1, row2, row3, row4, row5, row6, row7;
+   __m128i tmp;
+
+   // dot product constant: even elems=x, odd elems=y
+   #define dct_const(x,y)  _mm_setr_epi16((x),(y),(x),(y),(x),(y),(x),(y))
+
+   // out(0) = c0[even]*x + c0[odd]*y   (c0, x, y 16-bit, out 32-bit)
+   // out(1) = c1[even]*x + c1[odd]*y
+   #define dct_rot(out0,out1, x,y,c0,c1) \
+      __m128i c0##lo = _mm_unpacklo_epi16((x),(y)); \
+      __m128i c0##hi = _mm_unpackhi_epi16((x),(y)); \
+      __m128i out0##_l = _mm_madd_epi16(c0##lo, c0); \
+      __m128i out0##_h = _mm_madd_epi16(c0##hi, c0); \
+      __m128i out1##_l = _mm_madd_epi16(c0##lo, c1); \
+      __m128i out1##_h = _mm_madd_epi16(c0##hi, c1)
+
+   // out = in << 12  (in 16-bit, out 32-bit)
+   #define dct_widen(out, in) \
+      __m128i out##_l = _mm_srai_epi32(_mm_unpacklo_epi16(_mm_setzero_si128(), (in)), 4); \
+      __m128i out##_h = _mm_srai_epi32(_mm_unpackhi_epi16(_mm_setzero_si128(), (in)), 4)
+
+   // wide add
+   #define dct_wadd(out, a, b) \
+      __m128i out##_l = _mm_add_epi32(a##_l, b##_l); \
+      __m128i out##_h = _mm_add_epi32(a##_h, b##_h)
+
+   // wide sub
+   #define dct_wsub(out, a, b) \
+      __m128i out##_l = _mm_sub_epi32(a##_l, b##_l); \
+      __m128i out##_h = _mm_sub_epi32(a##_h, b##_h)
+
+   // butterfly a/b, add bias, then shift by "s" and pack
+   #define dct_bfly32o(out0, out1, a,b,bias,s) \
+      { \
+         __m128i abiased_l = _mm_add_epi32(a##_l, bias); \
+         __m128i abiased_h = _mm_add_epi32(a##_h, bias); \
+         dct_wadd(sum, abiased, b); \
+         dct_wsub(dif, abiased, b); \
+         out0 = _mm_packs_epi32(_mm_srai_epi32(sum_l, s), _mm_srai_epi32(sum_h, s)); \
+         out1 = _mm_packs_epi32(_mm_srai_epi32(dif_l, s), _mm_srai_epi32(dif_h, s)); \
+      }
+
+   // 8-bit interleave step (for transposes)
+   #define dct_interleave8(a, b) \
+      tmp = a; \
+      a = _mm_unpacklo_epi8(a, b); \
+      b = _mm_unpackhi_epi8(tmp, b)
+
+   // 16-bit interleave step (for transposes)
+   #define dct_interleave16(a, b) \
+      tmp = a; \
+      a = _mm_unpacklo_epi16(a, b); \
+      b = _mm_unpackhi_epi16(tmp, b)
+
+   #define dct_pass(bias,shift) \
+      { \
+         /* even part */ \
+         dct_rot(t2e,t3e, row2,row6, rot0_0,rot0_1); \
+         __m128i sum04 = _mm_add_epi16(row0, row4); \
+         __m128i dif04 = _mm_sub_epi16(row0, row4); \
+         dct_widen(t0e, sum04); \
+         dct_widen(t1e, dif04); \
+         dct_wadd(x0, t0e, t3e); \
+         dct_wsub(x3, t0e, t3e); \
+         dct_wadd(x1, t1e, t2e); \
+         dct_wsub(x2, t1e, t2e); \
+         /* odd part */ \
+         dct_rot(y0o,y2o, row7,row3, rot2_0,rot2_1); \
+         dct_rot(y1o,y3o, row5,row1, rot3_0,rot3_1); \
+         __m128i sum17 = _mm_add_epi16(row1, row7); \
+         __m128i sum35 = _mm_add_epi16(row3, row5); \
+         dct_rot(y4o,y5o, sum17,sum35, rot1_0,rot1_1); \
+         dct_wadd(x4, y0o, y4o); \
+         dct_wadd(x5, y1o, y5o); \
+         dct_wadd(x6, y2o, y5o); \
+         dct_wadd(x7, y3o, y4o); \
+         dct_bfly32o(row0,row7, x0,x7,bias,shift); \
+         dct_bfly32o(row1,row6, x1,x6,bias,shift); \
+         dct_bfly32o(row2,row5, x2,x5,bias,shift); \
+         dct_bfly32o(row3,row4, x3,x4,bias,shift); \
+      }
+
+   __m128i rot0_0 = dct_const(stbi__f2f(0.5411961f), stbi__f2f(0.5411961f) + stbi__f2f(-1.847759065f));
+   __m128i rot0_1 = dct_const(stbi__f2f(0.5411961f) + stbi__f2f( 0.765366865f), stbi__f2f(0.5411961f));
+   __m128i rot1_0 = dct_const(stbi__f2f(1.175875602f) + stbi__f2f(-0.899976223f), stbi__f2f(1.175875602f));
+   __m128i rot1_1 = dct_const(stbi__f2f(1.175875602f), stbi__f2f(1.175875602f) + stbi__f2f(-2.562915447f));
+   __m128i rot2_0 = dct_const(stbi__f2f(-1.961570560f) + stbi__f2f( 0.298631336f), stbi__f2f(-1.961570560f));
+   __m128i rot2_1 = dct_const(stbi__f2f(-1.961570560f), stbi__f2f(-1.961570560f) + stbi__f2f( 3.072711026f));
+   __m128i rot3_0 = dct_const(stbi__f2f(-0.390180644f) + stbi__f2f( 2.053119869f), stbi__f2f(-0.390180644f));
+   __m128i rot3_1 = dct_const(stbi__f2f(-0.390180644f), stbi__f2f(-0.390180644f) + stbi__f2f( 1.501321110f));
+
+   // rounding biases in column/row passes, see stbi__idct_block for explanation.
+   __m128i bias_0 = _mm_set1_epi32(512);
+   __m128i bias_1 = _mm_set1_epi32(65536 + (128<<17));
+
+   // load
+   row0 = _mm_load_si128((const __m128i *) (data + 0*8));
+   row1 = _mm_load_si128((const __m128i *) (data + 1*8));
+   row2 = _mm_load_si128((const __m128i *) (data + 2*8));
+   row3 = _mm_load_si128((const __m128i *) (data + 3*8));
+   row4 = _mm_load_si128((const __m128i *) (data + 4*8));
+   row5 = _mm_load_si128((const __m128i *) (data + 5*8));
+   row6 = _mm_load_si128((const __m128i *) (data + 6*8));
+   row7 = _mm_load_si128((const __m128i *) (data + 7*8));
+
+   // column pass
+   dct_pass(bias_0, 10);
+
+   {
+      // 16bit 8x8 transpose pass 1
+      dct_interleave16(row0, row4);
+      dct_interleave16(row1, row5);
+      dct_interleave16(row2, row6);
+      dct_interleave16(row3, row7);
+
+      // transpose pass 2
+      dct_interleave16(row0, row2);
+      dct_interleave16(row1, row3);
+      dct_interleave16(row4, row6);
+      dct_interleave16(row5, row7);
+
+      // transpose pass 3
+      dct_interleave16(row0, row1);
+      dct_interleave16(row2, row3);
+      dct_interleave16(row4, row5);
+      dct_interleave16(row6, row7);
+   }
+
+   // row pass
+   dct_pass(bias_1, 17);
+
+   {
+      // pack
+      __m128i p0 = _mm_packus_epi16(row0, row1); // a0a1a2a3...a7b0b1b2b3...b7
+      __m128i p1 = _mm_packus_epi16(row2, row3);
+      __m128i p2 = _mm_packus_epi16(row4, row5);
+      __m128i p3 = _mm_packus_epi16(row6, row7);
+
+      // 8bit 8x8 transpose pass 1
+      dct_interleave8(p0, p2); // a0e0a1e1...
+      dct_interleave8(p1, p3); // c0g0c1g1...
+
+      // transpose pass 2
+      dct_interleave8(p0, p1); // a0c0e0g0...
+      dct_interleave8(p2, p3); // b0d0f0h0...
+
+      // transpose pass 3
+      dct_interleave8(p0, p2); // a0b0c0d0...
+      dct_interleave8(p1, p3); // a4b4c4d4...
+
+      // store
+      _mm_storel_epi64((__m128i *) out, p0); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p0, 0x4e)); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, p2); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p2, 0x4e)); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, p1); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p1, 0x4e)); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, p3); out += out_stride;
+      _mm_storel_epi64((__m128i *) out, _mm_shuffle_epi32(p3, 0x4e));
+   }
+
+#undef dct_const
+#undef dct_rot
+#undef dct_widen
+#undef dct_wadd
+#undef dct_wsub
+#undef dct_bfly32o
+#undef dct_interleave8
+#undef dct_interleave16
+#undef dct_pass
+}
+
+#endif // STBI_SSE2
+
+#ifdef STBI_NEON
+
+// NEON integer IDCT. should produce bit-identical
+// results to the generic C version.
+static void stbi__idct_simd(stbi_uc *out, int out_stride, short data[64])
+{
+   int16x8_t row0, row1, row2, row3, row4, row5, row6, row7;
+
+   int16x4_t rot0_0 = vdup_n_s16(stbi__f2f(0.5411961f));
+   int16x4_t rot0_1 = vdup_n_s16(stbi__f2f(-1.847759065f));
+   int16x4_t rot0_2 = vdup_n_s16(stbi__f2f( 0.765366865f));
+   int16x4_t rot1_0 = vdup_n_s16(stbi__f2f( 1.175875602f));
+   int16x4_t rot1_1 = vdup_n_s16(stbi__f2f(-0.899976223f));
+   int16x4_t rot1_2 = vdup_n_s16(stbi__f2f(-2.562915447f));
+   int16x4_t rot2_0 = vdup_n_s16(stbi__f2f(-1.961570560f));
+   int16x4_t rot2_1 = vdup_n_s16(stbi__f2f(-0.390180644f));
+   int16x4_t rot3_0 = vdup_n_s16(stbi__f2f( 0.298631336f));
+   int16x4_t rot3_1 = vdup_n_s16(stbi__f2f( 2.053119869f));
+   int16x4_t rot3_2 = vdup_n_s16(stbi__f2f( 3.072711026f));
+   int16x4_t rot3_3 = vdup_n_s16(stbi__f2f( 1.501321110f));
+
+#define dct_long_mul(out, inq, coeff) \
+   int32x4_t out##_l = vmull_s16(vget_low_s16(inq), coeff); \
+   int32x4_t out##_h = vmull_s16(vget_high_s16(inq), coeff)
+
+#define dct_long_mac(out, acc, inq, coeff) \
+   int32x4_t out##_l = vmlal_s16(acc##_l, vget_low_s16(inq), coeff); \
+   int32x4_t out##_h = vmlal_s16(acc##_h, vget_high_s16(inq), coeff)
+
+#define dct_widen(out, inq) \
+   int32x4_t out##_l = vshll_n_s16(vget_low_s16(inq), 12); \
+   int32x4_t out##_h = vshll_n_s16(vget_high_s16(inq), 12)
+
+// wide add
+#define dct_wadd(out, a, b) \
+   int32x4_t out##_l = vaddq_s32(a##_l, b##_l); \
+   int32x4_t out##_h = vaddq_s32(a##_h, b##_h)
+
+// wide sub
+#define dct_wsub(out, a, b) \
+   int32x4_t out##_l = vsubq_s32(a##_l, b##_l); \
+   int32x4_t out##_h = vsubq_s32(a##_h, b##_h)
+
+// butterfly a/b, then shift using "shiftop" by "s" and pack
+#define dct_bfly32o(out0,out1, a,b,shiftop,s) \
+   { \
+      dct_wadd(sum, a, b); \
+      dct_wsub(dif, a, b); \
+      out0 = vcombine_s16(shiftop(sum_l, s), shiftop(sum_h, s)); \
+      out1 = vcombine_s16(shiftop(dif_l, s), shiftop(dif_h, s)); \
+   }
+
+#define dct_pass(shiftop, shift) \
+   { \
+      /* even part */ \
+      int16x8_t sum26 = vaddq_s16(row2, row6); \
+      dct_long_mul(p1e, sum26, rot0_0); \
+      dct_long_mac(t2e, p1e, row6, rot0_1); \
+      dct_long_mac(t3e, p1e, row2, rot0_2); \
+      int16x8_t sum04 = vaddq_s16(row0, row4); \
+      int16x8_t dif04 = vsubq_s16(row0, row4); \
+      dct_widen(t0e, sum04); \
+      dct_widen(t1e, dif04); \
+      dct_wadd(x0, t0e, t3e); \
+      dct_wsub(x3, t0e, t3e); \
+      dct_wadd(x1, t1e, t2e); \
+      dct_wsub(x2, t1e, t2e); \
+      /* odd part */ \
+      int16x8_t sum15 = vaddq_s16(row1, row5); \
+      int16x8_t sum17 = vaddq_s16(row1, row7); \
+      int16x8_t sum35 = vaddq_s16(row3, row5); \
+      int16x8_t sum37 = vaddq_s16(row3, row7); \
+      int16x8_t sumodd = vaddq_s16(sum17, sum35); \
+      dct_long_mul(p5o, sumodd, rot1_0); \
+      dct_long_mac(p1o, p5o, sum17, rot1_1); \
+      dct_long_mac(p2o, p5o, sum35, rot1_2); \
+      dct_long_mul(p3o, sum37, rot2_0); \
+      dct_long_mul(p4o, sum15, rot2_1); \
+      dct_wadd(sump13o, p1o, p3o); \
+      dct_wadd(sump24o, p2o, p4o); \
+      dct_wadd(sump23o, p2o, p3o); \
+      dct_wadd(sump14o, p1o, p4o); \
+      dct_long_mac(x4, sump13o, row7, rot3_0); \
+      dct_long_mac(x5, sump24o, row5, rot3_1); \
+      dct_long_mac(x6, sump23o, row3, rot3_2); \
+      dct_long_mac(x7, sump14o, row1, rot3_3); \
+      dct_bfly32o(row0,row7, x0,x7,shiftop,shift); \
+      dct_bfly32o(row1,row6, x1,x6,shiftop,shift); \
+      dct_bfly32o(row2,row5, x2,x5,shiftop,shift); \
+      dct_bfly32o(row3,row4, x3,x4,shiftop,shift); \
+   }
+
+   // load
+   row0 = vld1q_s16(data + 0*8);
+   row1 = vld1q_s16(data + 1*8);
+   row2 = vld1q_s16(data + 2*8);
+   row3 = vld1q_s16(data + 3*8);
+   row4 = vld1q_s16(data + 4*8);
+   row5 = vld1q_s16(data + 5*8);
+   row6 = vld1q_s16(data + 6*8);
+   row7 = vld1q_s16(data + 7*8);
+
+   // add DC bias
+   row0 = vaddq_s16(row0, vsetq_lane_s16(1024, vdupq_n_s16(0), 0));
+
+   // column pass
+   dct_pass(vrshrn_n_s32, 10);
+
+   // 16bit 8x8 transpose
+   {
+// these three map to a single VTRN.16, VTRN.32, and VSWP, respectively.
+// whether compilers actually get this is another story, sadly.
+#define dct_trn16(x, y) { int16x8x2_t t = vtrnq_s16(x, y); x = t.val[0]; y = t.val[1]; }
+#define dct_trn32(x, y) { int32x4x2_t t = vtrnq_s32(vreinterpretq_s32_s16(x), vreinterpretq_s32_s16(y)); x = vreinterpretq_s16_s32(t.val[0]); y = vreinterpretq_s16_s32(t.val[1]); }
+#define dct_trn64(x, y) { int16x8_t x0 = x; int16x8_t y0 = y; x = vcombine_s16(vget_low_s16(x0), vget_low_s16(y0)); y = vcombine_s16(vget_high_s16(x0), vget_high_s16(y0)); }
+
+      // pass 1
+      dct_trn16(row0, row1); // a0b0a2b2a4b4a6b6
+      dct_trn16(row2, row3);
+      dct_trn16(row4, row5);
+      dct_trn16(row6, row7);
+
+      // pass 2
+      dct_trn32(row0, row2); // a0b0c0d0a4b4c4d4
+      dct_trn32(row1, row3);
+      dct_trn32(row4, row6);
+      dct_trn32(row5, row7);
+
+      // pass 3
+      dct_trn64(row0, row4); // a0b0c0d0e0f0g0h0
+      dct_trn64(row1, row5);
+      dct_trn64(row2, row6);
+      dct_trn64(row3, row7);
+
+#undef dct_trn16
+#undef dct_trn32
+#undef dct_trn64
+   }
+
+   // row pass
+   // vrshrn_n_s32 only supports shifts up to 16, we need
+   // 17. so do a non-rounding shift of 16 first then follow
+   // up with a rounding shift by 1.
+   dct_pass(vshrn_n_s32, 16);
+
+   {
+      // pack and round
+      uint8x8_t p0 = vqrshrun_n_s16(row0, 1);
+      uint8x8_t p1 = vqrshrun_n_s16(row1, 1);
+      uint8x8_t p2 = vqrshrun_n_s16(row2, 1);
+      uint8x8_t p3 = vqrshrun_n_s16(row3, 1);
+      uint8x8_t p4 = vqrshrun_n_s16(row4, 1);
+      uint8x8_t p5 = vqrshrun_n_s16(row5, 1);
+      uint8x8_t p6 = vqrshrun_n_s16(row6, 1);
+      uint8x8_t p7 = vqrshrun_n_s16(row7, 1);
+
+      // again, these can translate into one instruction, but often don't.
+#define dct_trn8_8(x, y) { uint8x8x2_t t = vtrn_u8(x, y); x = t.val[0]; y = t.val[1]; }
+#define dct_trn8_16(x, y) { uint16x4x2_t t = vtrn_u16(vreinterpret_u16_u8(x), vreinterpret_u16_u8(y)); x = vreinterpret_u8_u16(t.val[0]); y = vreinterpret_u8_u16(t.val[1]); }
+#define dct_trn8_32(x, y) { uint32x2x2_t t = vtrn_u32(vreinterpret_u32_u8(x), vreinterpret_u32_u8(y)); x = vreinterpret_u8_u32(t.val[0]); y = vreinterpret_u8_u32(t.val[1]); }
+
+      // sadly can't use interleaved stores here since we only write
+      // 8 bytes to each scan line!
+
+      // 8x8 8-bit transpose pass 1
+      dct_trn8_8(p0, p1);
+      dct_trn8_8(p2, p3);
+      dct_trn8_8(p4, p5);
+      dct_trn8_8(p6, p7);
+
+      // pass 2
+      dct_trn8_16(p0, p2);
+      dct_trn8_16(p1, p3);
+      dct_trn8_16(p4, p6);
+      dct_trn8_16(p5, p7);
+
+      // pass 3
+      dct_trn8_32(p0, p4);
+      dct_trn8_32(p1, p5);
+      dct_trn8_32(p2, p6);
+      dct_trn8_32(p3, p7);
+
+      // store
+      vst1_u8(out, p0); out += out_stride;
+      vst1_u8(out, p1); out += out_stride;
+      vst1_u8(out, p2); out += out_stride;
+      vst1_u8(out, p3); out += out_stride;
+      vst1_u8(out, p4); out += out_stride;
+      vst1_u8(out, p5); out += out_stride;
+      vst1_u8(out, p6); out += out_stride;
+      vst1_u8(out, p7);
+
+#undef dct_trn8_8
+#undef dct_trn8_16
+#undef dct_trn8_32
+   }
+
+#undef dct_long_mul
+#undef dct_long_mac
+#undef dct_widen
+#undef dct_wadd
+#undef dct_wsub
+#undef dct_bfly32o
+#undef dct_pass
+}
+
+#endif // STBI_NEON
+
+#define STBI__MARKER_none  0xff
+// if there's a pending marker from the entropy stream, return that
+// otherwise, fetch from the stream and get a marker. if there's no
+// marker, return 0xff, which is never a valid marker value
+static stbi_uc stbi__get_marker(stbi__jpeg *j)
+{
+   stbi_uc x;
+   if (j->marker != STBI__MARKER_none) { x = j->marker; j->marker = STBI__MARKER_none; return x; }
+   x = stbi__get8(j->s);
+   if (x != 0xff) return STBI__MARKER_none;
+   while (x == 0xff)
+      x = stbi__get8(j->s); // consume repeated 0xff fill bytes
+   return x;
+}
+
+// in each scan, we'll have scan_n components, and the order
+// of the components is specified by order[]
+#define STBI__RESTART(x)     ((x) >= 0xd0 && (x) <= 0xd7)
+
+// after a restart interval, stbi__jpeg_reset the entropy decoder and
+// the dc prediction
+static void stbi__jpeg_reset(stbi__jpeg *j)
+{
+   j->code_bits = 0;
+   j->code_buffer = 0;
+   j->nomore = 0;
+   j->img_comp[0].dc_pred = j->img_comp[1].dc_pred = j->img_comp[2].dc_pred = j->img_comp[3].dc_pred = 0;
+   j->marker = STBI__MARKER_none;
+   j->todo = j->restart_interval ? j->restart_interval : 0x7fffffff;
+   j->eob_run = 0;
+   // no more than 1<<31 MCUs if no restart_interal? that's plenty safe,
+   // since we don't even allow 1<<30 pixels
+}
+
+static int stbi__parse_entropy_coded_data(stbi__jpeg *z)
+{
+   stbi__jpeg_reset(z);
+   if (!z->progressive) {
+      if (z->scan_n == 1) {
+         int i,j;
+         STBI_SIMD_ALIGN(short, data[64]);
+         int n = z->order[0];
+         // non-interleaved data, we just need to process one block at a time,
+         // in trivial scanline order
+         // number of blocks to do just depends on how many actual "pixels" this
+         // component has, independent of interleaved MCU blocking and such
+         int w = (z->img_comp[n].x+7) >> 3;
+         int h = (z->img_comp[n].y+7) >> 3;
+         for (j=0; j < h; ++j) {
+            for (i=0; i < w; ++i) {
+               int ha = z->img_comp[n].ha;
+               if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0;
+               z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data);
+               // every data block is an MCU, so countdown the restart interval
+               if (--z->todo <= 0) {
+                  if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
+                  // if it's NOT a restart, then just bail, so we get corrupt data
+                  // rather than no data
+                  if (!STBI__RESTART(z->marker)) return 1;
+                  stbi__jpeg_reset(z);
+               }
+            }
+         }
+         return 1;
+      } else { // interleaved
+         int i,j,k,x,y;
+         STBI_SIMD_ALIGN(short, data[64]);
+         for (j=0; j < z->img_mcu_y; ++j) {
+            for (i=0; i < z->img_mcu_x; ++i) {
+               // scan an interleaved mcu... process scan_n components in order
+               for (k=0; k < z->scan_n; ++k) {
+                  int n = z->order[k];
+                  // scan out an mcu's worth of this component; that's just determined
+                  // by the basic H and V specified for the component
+                  for (y=0; y < z->img_comp[n].v; ++y) {
+                     for (x=0; x < z->img_comp[n].h; ++x) {
+                        int x2 = (i*z->img_comp[n].h + x)*8;
+                        int y2 = (j*z->img_comp[n].v + y)*8;
+                        int ha = z->img_comp[n].ha;
+                        if (!stbi__jpeg_decode_block(z, data, z->huff_dc+z->img_comp[n].hd, z->huff_ac+ha, z->fast_ac[ha], n, z->dequant[z->img_comp[n].tq])) return 0;
+                        z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*y2+x2, z->img_comp[n].w2, data);
+                     }
+                  }
+               }
+               // after all interleaved components, that's an interleaved MCU,
+               // so now count down the restart interval
+               if (--z->todo <= 0) {
+                  if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
+                  if (!STBI__RESTART(z->marker)) return 1;
+                  stbi__jpeg_reset(z);
+               }
+            }
+         }
+         return 1;
+      }
+   } else {
+      if (z->scan_n == 1) {
+         int i,j;
+         int n = z->order[0];
+         // non-interleaved data, we just need to process one block at a time,
+         // in trivial scanline order
+         // number of blocks to do just depends on how many actual "pixels" this
+         // component has, independent of interleaved MCU blocking and such
+         int w = (z->img_comp[n].x+7) >> 3;
+         int h = (z->img_comp[n].y+7) >> 3;
+         for (j=0; j < h; ++j) {
+            for (i=0; i < w; ++i) {
+               short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w);
+               if (z->spec_start == 0) {
+                  if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n))
+                     return 0;
+               } else {
+                  int ha = z->img_comp[n].ha;
+                  if (!stbi__jpeg_decode_block_prog_ac(z, data, &z->huff_ac[ha], z->fast_ac[ha]))
+                     return 0;
+               }
+               // every data block is an MCU, so countdown the restart interval
+               if (--z->todo <= 0) {
+                  if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
+                  if (!STBI__RESTART(z->marker)) return 1;
+                  stbi__jpeg_reset(z);
+               }
+            }
+         }
+         return 1;
+      } else { // interleaved
+         int i,j,k,x,y;
+         for (j=0; j < z->img_mcu_y; ++j) {
+            for (i=0; i < z->img_mcu_x; ++i) {
+               // scan an interleaved mcu... process scan_n components in order
+               for (k=0; k < z->scan_n; ++k) {
+                  int n = z->order[k];
+                  // scan out an mcu's worth of this component; that's just determined
+                  // by the basic H and V specified for the component
+                  for (y=0; y < z->img_comp[n].v; ++y) {
+                     for (x=0; x < z->img_comp[n].h; ++x) {
+                        int x2 = (i*z->img_comp[n].h + x);
+                        int y2 = (j*z->img_comp[n].v + y);
+                        short *data = z->img_comp[n].coeff + 64 * (x2 + y2 * z->img_comp[n].coeff_w);
+                        if (!stbi__jpeg_decode_block_prog_dc(z, data, &z->huff_dc[z->img_comp[n].hd], n))
+                           return 0;
+                     }
+                  }
+               }
+               // after all interleaved components, that's an interleaved MCU,
+               // so now count down the restart interval
+               if (--z->todo <= 0) {
+                  if (z->code_bits < 24) stbi__grow_buffer_unsafe(z);
+                  if (!STBI__RESTART(z->marker)) return 1;
+                  stbi__jpeg_reset(z);
+               }
+            }
+         }
+         return 1;
+      }
+   }
+}
+
+static void stbi__jpeg_dequantize(short *data, stbi__uint16 *dequant)
+{
+   int i;
+   for (i=0; i < 64; ++i)
+      data[i] *= dequant[i];
+}
+
+static void stbi__jpeg_finish(stbi__jpeg *z)
+{
+   if (z->progressive) {
+      // dequantize and idct the data
+      int i,j,n;
+      for (n=0; n < z->s->img_n; ++n) {
+         int w = (z->img_comp[n].x+7) >> 3;
+         int h = (z->img_comp[n].y+7) >> 3;
+         for (j=0; j < h; ++j) {
+            for (i=0; i < w; ++i) {
+               short *data = z->img_comp[n].coeff + 64 * (i + j * z->img_comp[n].coeff_w);
+               stbi__jpeg_dequantize(data, z->dequant[z->img_comp[n].tq]);
+               z->idct_block_kernel(z->img_comp[n].data+z->img_comp[n].w2*j*8+i*8, z->img_comp[n].w2, data);
+            }
+         }
+      }
+   }
+}
+
+static int stbi__process_marker(stbi__jpeg *z, int m)
+{
+   int L;
+   switch (m) {
+      case STBI__MARKER_none: // no marker found
+         return stbi__err("expected marker","Corrupt JPEG");
+
+      case 0xDD: // DRI - specify restart interval
+         if (stbi__get16be(z->s) != 4) return stbi__err("bad DRI len","Corrupt JPEG");
+         z->restart_interval = stbi__get16be(z->s);
+         return 1;
+
+      case 0xDB: // DQT - define quantization table
+         L = stbi__get16be(z->s)-2;
+         while (L > 0) {
+            int q = stbi__get8(z->s);
+            int p = q >> 4, sixteen = (p != 0);
+            int t = q & 15,i;
+            if (p != 0 && p != 1) return stbi__err("bad DQT type","Corrupt JPEG");
+            if (t > 3) return stbi__err("bad DQT table","Corrupt JPEG");
+
+            for (i=0; i < 64; ++i)
+               z->dequant[t][stbi__jpeg_dezigzag[i]] = (stbi__uint16)(sixteen ? stbi__get16be(z->s) : stbi__get8(z->s));
+            L -= (sixteen ? 129 : 65);
+         }
+         return L==0;
+
+      case 0xC4: // DHT - define huffman table
+         L = stbi__get16be(z->s)-2;
+         while (L > 0) {
+            stbi_uc *v;
+            int sizes[16],i,n=0;
+            int q = stbi__get8(z->s);
+            int tc = q >> 4;
+            int th = q & 15;
+            if (tc > 1 || th > 3) return stbi__err("bad DHT header","Corrupt JPEG");
+            for (i=0; i < 16; ++i) {
+               sizes[i] = stbi__get8(z->s);
+               n += sizes[i];
+            }
+            L -= 17;
+            if (tc == 0) {
+               if (!stbi__build_huffman(z->huff_dc+th, sizes)) return 0;
+               v = z->huff_dc[th].values;
+            } else {
+               if (!stbi__build_huffman(z->huff_ac+th, sizes)) return 0;
+               v = z->huff_ac[th].values;
+            }
+            for (i=0; i < n; ++i)
+               v[i] = stbi__get8(z->s);
+            if (tc != 0)
+               stbi__build_fast_ac(z->fast_ac[th], z->huff_ac + th);
+            L -= n;
+         }
+         return L==0;
+   }
+
+   // check for comment block or APP blocks
+   if ((m >= 0xE0 && m <= 0xEF) || m == 0xFE) {
+      L = stbi__get16be(z->s);
+      if (L < 2) {
+         if (m == 0xFE)
+            return stbi__err("bad COM len","Corrupt JPEG");
+         else
+            return stbi__err("bad APP len","Corrupt JPEG");
+      }
+      L -= 2;
+
+      if (m == 0xE0 && L >= 5) { // JFIF APP0 segment
+         static const unsigned char tag[5] = {'J','F','I','F','\0'};
+         int ok = 1;
+         int i;
+         for (i=0; i < 5; ++i)
+            if (stbi__get8(z->s) != tag[i])
+               ok = 0;
+         L -= 5;
+         if (ok)
+            z->jfif = 1;
+      } else if (m == 0xEE && L >= 12) { // Adobe APP14 segment
+         static const unsigned char tag[6] = {'A','d','o','b','e','\0'};
+         int ok = 1;
+         int i;
+         for (i=0; i < 6; ++i)
+            if (stbi__get8(z->s) != tag[i])
+               ok = 0;
+         L -= 6;
+         if (ok) {
+            stbi__get8(z->s); // version
+            stbi__get16be(z->s); // flags0
+            stbi__get16be(z->s); // flags1
+            z->app14_color_transform = stbi__get8(z->s); // color transform
+            L -= 6;
+         }
+      }
+
+      stbi__skip(z->s, L);
+      return 1;
+   }
+
+   return stbi__err("unknown marker","Corrupt JPEG");
+}
+
+// after we see SOS
+static int stbi__process_scan_header(stbi__jpeg *z)
+{
+   int i;
+   int Ls = stbi__get16be(z->s);
+   z->scan_n = stbi__get8(z->s);
+   if (z->scan_n < 1 || z->scan_n > 4 || z->scan_n > (int) z->s->img_n) return stbi__err("bad SOS component count","Corrupt JPEG");
+   if (Ls != 6+2*z->scan_n) return stbi__err("bad SOS len","Corrupt JPEG");
+   for (i=0; i < z->scan_n; ++i) {
+      int id = stbi__get8(z->s), which;
+      int q = stbi__get8(z->s);
+      for (which = 0; which < z->s->img_n; ++which)
+         if (z->img_comp[which].id == id)
+            break;
+      if (which == z->s->img_n) return 0; // no match
+      z->img_comp[which].hd = q >> 4;   if (z->img_comp[which].hd > 3) return stbi__err("bad DC huff","Corrupt JPEG");
+      z->img_comp[which].ha = q & 15;   if (z->img_comp[which].ha > 3) return stbi__err("bad AC huff","Corrupt JPEG");
+      z->order[i] = which;
+   }
+
+   {
+      int aa;
+      z->spec_start = stbi__get8(z->s);
+      z->spec_end   = stbi__get8(z->s); // should be 63, but might be 0
+      aa = stbi__get8(z->s);
+      z->succ_high = (aa >> 4);
+      z->succ_low  = (aa & 15);
+      if (z->progressive) {
+         if (z->spec_start > 63 || z->spec_end > 63  || z->spec_start > z->spec_end || z->succ_high > 13 || z->succ_low > 13)
+            return stbi__err("bad SOS", "Corrupt JPEG");
+      } else {
+         if (z->spec_start != 0) return stbi__err("bad SOS","Corrupt JPEG");
+         if (z->succ_high != 0 || z->succ_low != 0) return stbi__err("bad SOS","Corrupt JPEG");
+         z->spec_end = 63;
+      }
+   }
+
+   return 1;
+}
+
+static int stbi__free_jpeg_components(stbi__jpeg *z, int ncomp, int why)
+{
+   int i;
+   for (i=0; i < ncomp; ++i) {
+      if (z->img_comp[i].raw_data) {
+         STBI_FREE(z->img_comp[i].raw_data);
+         z->img_comp[i].raw_data = NULL;
+         z->img_comp[i].data = NULL;
+      }
+      if (z->img_comp[i].raw_coeff) {
+         STBI_FREE(z->img_comp[i].raw_coeff);
+         z->img_comp[i].raw_coeff = 0;
+         z->img_comp[i].coeff = 0;
+      }
+      if (z->img_comp[i].linebuf) {
+         STBI_FREE(z->img_comp[i].linebuf);
+         z->img_comp[i].linebuf = NULL;
+      }
+   }
+   return why;
+}
+
+static int stbi__process_frame_header(stbi__jpeg *z, int scan)
+{
+   stbi__context *s = z->s;
+   int Lf,p,i,q, h_max=1,v_max=1,c;
+   Lf = stbi__get16be(s);         if (Lf < 11) return stbi__err("bad SOF len","Corrupt JPEG"); // JPEG
+   p  = stbi__get8(s);            if (p != 8) return stbi__err("only 8-bit","JPEG format not supported: 8-bit only"); // JPEG baseline
+   s->img_y = stbi__get16be(s);   if (s->img_y == 0) return stbi__err("no header height", "JPEG format not supported: delayed height"); // Legal, but we don't handle it--but neither does IJG
+   s->img_x = stbi__get16be(s);   if (s->img_x == 0) return stbi__err("0 width","Corrupt JPEG"); // JPEG requires
+   c = stbi__get8(s);
+   if (c != 3 && c != 1 && c != 4) return stbi__err("bad component count","Corrupt JPEG");
+   s->img_n = c;
+   for (i=0; i < c; ++i) {
+      z->img_comp[i].data = NULL;
+      z->img_comp[i].linebuf = NULL;
+   }
+
+   if (Lf != 8+3*s->img_n) return stbi__err("bad SOF len","Corrupt JPEG");
+
+   z->rgb = 0;
+   for (i=0; i < s->img_n; ++i) {
+      static const unsigned char rgb[3] = { 'R', 'G', 'B' };
+      z->img_comp[i].id = stbi__get8(s);
+      if (s->img_n == 3 && z->img_comp[i].id == rgb[i])
+         ++z->rgb;
+      q = stbi__get8(s);
+      z->img_comp[i].h = (q >> 4);  if (!z->img_comp[i].h || z->img_comp[i].h > 4) return stbi__err("bad H","Corrupt JPEG");
+      z->img_comp[i].v = q & 15;    if (!z->img_comp[i].v || z->img_comp[i].v > 4) return stbi__err("bad V","Corrupt JPEG");
+      z->img_comp[i].tq = stbi__get8(s);  if (z->img_comp[i].tq > 3) return stbi__err("bad TQ","Corrupt JPEG");
+   }
+
+   if (scan != STBI__SCAN_load) return 1;
+
+   if (!stbi__mad3sizes_valid(s->img_x, s->img_y, s->img_n, 0)) return stbi__err("too large", "Image too large to decode");
+
+   for (i=0; i < s->img_n; ++i) {
+      if (z->img_comp[i].h > h_max) h_max = z->img_comp[i].h;
+      if (z->img_comp[i].v > v_max) v_max = z->img_comp[i].v;
+   }
+
+   // compute interleaved mcu info
+   z->img_h_max = h_max;
+   z->img_v_max = v_max;
+   z->img_mcu_w = h_max * 8;
+   z->img_mcu_h = v_max * 8;
+   // these sizes can't be more than 17 bits
+   z->img_mcu_x = (s->img_x + z->img_mcu_w-1) / z->img_mcu_w;
+   z->img_mcu_y = (s->img_y + z->img_mcu_h-1) / z->img_mcu_h;
+
+   for (i=0; i < s->img_n; ++i) {
+      // number of effective pixels (e.g. for non-interleaved MCU)
+      z->img_comp[i].x = (s->img_x * z->img_comp[i].h + h_max-1) / h_max;
+      z->img_comp[i].y = (s->img_y * z->img_comp[i].v + v_max-1) / v_max;
+      // to simplify generation, we'll allocate enough memory to decode
+      // the bogus oversized data from using interleaved MCUs and their
+      // big blocks (e.g. a 16x16 iMCU on an image of width 33); we won't
+      // discard the extra data until colorspace conversion
+      //
+      // img_mcu_x, img_mcu_y: <=17 bits; comp[i].h and .v are <=4 (checked earlier)
+      // so these muls can't overflow with 32-bit ints (which we require)
+      z->img_comp[i].w2 = z->img_mcu_x * z->img_comp[i].h * 8;
+      z->img_comp[i].h2 = z->img_mcu_y * z->img_comp[i].v * 8;
+      z->img_comp[i].coeff = 0;
+      z->img_comp[i].raw_coeff = 0;
+      z->img_comp[i].linebuf = NULL;
+      z->img_comp[i].raw_data = stbi__malloc_mad2(z->img_comp[i].w2, z->img_comp[i].h2, 15);
+      if (z->img_comp[i].raw_data == NULL)
+         return stbi__free_jpeg_components(z, i+1, stbi__err("outofmem", "Out of memory"));
+      // align blocks for idct using mmx/sse
+      z->img_comp[i].data = (stbi_uc*) (((size_t) z->img_comp[i].raw_data + 15) & ~15);
+      if (z->progressive) {
+         // w2, h2 are multiples of 8 (see above)
+         z->img_comp[i].coeff_w = z->img_comp[i].w2 / 8;
+         z->img_comp[i].coeff_h = z->img_comp[i].h2 / 8;
+         z->img_comp[i].raw_coeff = stbi__malloc_mad3(z->img_comp[i].w2, z->img_comp[i].h2, sizeof(short), 15);
+         if (z->img_comp[i].raw_coeff == NULL)
+            return stbi__free_jpeg_components(z, i+1, stbi__err("outofmem", "Out of memory"));
+         z->img_comp[i].coeff = (short*) (((size_t) z->img_comp[i].raw_coeff + 15) & ~15);
+      }
+   }
+
+   return 1;
+}
+
+// use comparisons since in some cases we handle more than one case (e.g. SOF)
+#define stbi__DNL(x)         ((x) == 0xdc)
+#define stbi__SOI(x)         ((x) == 0xd8)
+#define stbi__EOI(x)         ((x) == 0xd9)
+#define stbi__SOF(x)         ((x) == 0xc0 || (x) == 0xc1 || (x) == 0xc2)
+#define stbi__SOS(x)         ((x) == 0xda)
+
+#define stbi__SOF_progressive(x)   ((x) == 0xc2)
+
+static int stbi__decode_jpeg_header(stbi__jpeg *z, int scan)
+{
+   int m;
+   z->jfif = 0;
+   z->app14_color_transform = -1; // valid values are 0,1,2
+   z->marker = STBI__MARKER_none; // initialize cached marker to empty
+   m = stbi__get_marker(z);
+   if (!stbi__SOI(m)) return stbi__err("no SOI","Corrupt JPEG");
+   if (scan == STBI__SCAN_type) return 1;
+   m = stbi__get_marker(z);
+   while (!stbi__SOF(m)) {
+      if (!stbi__process_marker(z,m)) return 0;
+      m = stbi__get_marker(z);
+      while (m == STBI__MARKER_none) {
+         // some files have extra padding after their blocks, so ok, we'll scan
+         if (stbi__at_eof(z->s)) return stbi__err("no SOF", "Corrupt JPEG");
+         m = stbi__get_marker(z);
+      }
+   }
+   z->progressive = stbi__SOF_progressive(m);
+   if (!stbi__process_frame_header(z, scan)) return 0;
+   return 1;
+}
+
+// decode image to YCbCr format
+static int stbi__decode_jpeg_image(stbi__jpeg *j)
+{
+   int m;
+   for (m = 0; m < 4; m++) {
+      j->img_comp[m].raw_data = NULL;
+      j->img_comp[m].raw_coeff = NULL;
+   }
+   j->restart_interval = 0;
+   if (!stbi__decode_jpeg_header(j, STBI__SCAN_load)) return 0;
+   m = stbi__get_marker(j);
+   while (!stbi__EOI(m)) {
+      if (stbi__SOS(m)) {
+         if (!stbi__process_scan_header(j)) return 0;
+         if (!stbi__parse_entropy_coded_data(j)) return 0;
+         if (j->marker == STBI__MARKER_none ) {
+            // handle 0s at the end of image data from IP Kamera 9060
+            while (!stbi__at_eof(j->s)) {
+               int x = stbi__get8(j->s);
+               if (x == 255) {
+                  j->marker = stbi__get8(j->s);
+                  break;
+               }
+            }
+            // if we reach eof without hitting a marker, stbi__get_marker() below will fail and we'll eventually return 0
+         }
+      } else if (stbi__DNL(m)) {
+         int Ld = stbi__get16be(j->s);
+         stbi__uint32 NL = stbi__get16be(j->s);
+         if (Ld != 4) return stbi__err("bad DNL len", "Corrupt JPEG");
+         if (NL != j->s->img_y) return stbi__err("bad DNL height", "Corrupt JPEG");
+      } else {
+         if (!stbi__process_marker(j, m)) return 0;
+      }
+      m = stbi__get_marker(j);
+   }
+   if (j->progressive)
+      stbi__jpeg_finish(j);
+   return 1;
+}
+
+// static jfif-centered resampling (across block boundaries)
+
+typedef stbi_uc *(*resample_row_func)(stbi_uc *out, stbi_uc *in0, stbi_uc *in1,
+                                    int w, int hs);
+
+#define stbi__div4(x) ((stbi_uc) ((x) >> 2))
+
+static stbi_uc *resample_row_1(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
+{
+   STBI_NOTUSED(out);
+   STBI_NOTUSED(in_far);
+   STBI_NOTUSED(w);
+   STBI_NOTUSED(hs);
+   return in_near;
+}
+
+static stbi_uc* stbi__resample_row_v_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
+{
+   // need to generate two samples vertically for every one in input
+   int i;
+   STBI_NOTUSED(hs);
+   for (i=0; i < w; ++i)
+      out[i] = stbi__div4(3*in_near[i] + in_far[i] + 2);
+   return out;
+}
+
+static stbi_uc*  stbi__resample_row_h_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
+{
+   // need to generate two samples horizontally for every one in input
+   int i;
+   stbi_uc *input = in_near;
+
+   if (w == 1) {
+      // if only one sample, can't do any interpolation
+      out[0] = out[1] = input[0];
+      return out;
+   }
+
+   out[0] = input[0];
+   out[1] = stbi__div4(input[0]*3 + input[1] + 2);
+   for (i=1; i < w-1; ++i) {
+      int n = 3*input[i]+2;
+      out[i*2+0] = stbi__div4(n+input[i-1]);
+      out[i*2+1] = stbi__div4(n+input[i+1]);
+   }
+   out[i*2+0] = stbi__div4(input[w-2]*3 + input[w-1] + 2);
+   out[i*2+1] = input[w-1];
+
+   STBI_NOTUSED(in_far);
+   STBI_NOTUSED(hs);
+
+   return out;
+}
+
+#define stbi__div16(x) ((stbi_uc) ((x) >> 4))
+
+static stbi_uc *stbi__resample_row_hv_2(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
+{
+   // need to generate 2x2 samples for every one in input
+   int i,t0,t1;
+   if (w == 1) {
+      out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2);
+      return out;
+   }
+
+   t1 = 3*in_near[0] + in_far[0];
+   out[0] = stbi__div4(t1+2);
+   for (i=1; i < w; ++i) {
+      t0 = t1;
+      t1 = 3*in_near[i]+in_far[i];
+      out[i*2-1] = stbi__div16(3*t0 + t1 + 8);
+      out[i*2  ] = stbi__div16(3*t1 + t0 + 8);
+   }
+   out[w*2-1] = stbi__div4(t1+2);
+
+   STBI_NOTUSED(hs);
+
+   return out;
+}
+
+#if defined(STBI_SSE2) || defined(STBI_NEON)
+static stbi_uc *stbi__resample_row_hv_2_simd(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
+{
+   // need to generate 2x2 samples for every one in input
+   int i=0,t0,t1;
+
+   if (w == 1) {
+      out[0] = out[1] = stbi__div4(3*in_near[0] + in_far[0] + 2);
+      return out;
+   }
+
+   t1 = 3*in_near[0] + in_far[0];
+   // process groups of 8 pixels for as long as we can.
+   // note we can't handle the last pixel in a row in this loop
+   // because we need to handle the filter boundary conditions.
+   for (; i < ((w-1) & ~7); i += 8) {
+#if defined(STBI_SSE2)
+      // load and perform the vertical filtering pass
+      // this uses 3*x + y = 4*x + (y - x)
+      __m128i zero  = _mm_setzero_si128();
+      __m128i farb  = _mm_loadl_epi64((__m128i *) (in_far + i));
+      __m128i nearb = _mm_loadl_epi64((__m128i *) (in_near + i));
+      __m128i farw  = _mm_unpacklo_epi8(farb, zero);
+      __m128i nearw = _mm_unpacklo_epi8(nearb, zero);
+      __m128i diff  = _mm_sub_epi16(farw, nearw);
+      __m128i nears = _mm_slli_epi16(nearw, 2);
+      __m128i curr  = _mm_add_epi16(nears, diff); // current row
+
+      // horizontal filter works the same based on shifted vers of current
+      // row. "prev" is current row shifted right by 1 pixel; we need to
+      // insert the previous pixel value (from t1).
+      // "next" is current row shifted left by 1 pixel, with first pixel
+      // of next block of 8 pixels added in.
+      __m128i prv0 = _mm_slli_si128(curr, 2);
+      __m128i nxt0 = _mm_srli_si128(curr, 2);
+      __m128i prev = _mm_insert_epi16(prv0, t1, 0);
+      __m128i next = _mm_insert_epi16(nxt0, 3*in_near[i+8] + in_far[i+8], 7);
+
+      // horizontal filter, polyphase implementation since it's convenient:
+      // even pixels = 3*cur + prev = cur*4 + (prev - cur)
+      // odd  pixels = 3*cur + next = cur*4 + (next - cur)
+      // note the shared term.
+      __m128i bias  = _mm_set1_epi16(8);
+      __m128i curs = _mm_slli_epi16(curr, 2);
+      __m128i prvd = _mm_sub_epi16(prev, curr);
+      __m128i nxtd = _mm_sub_epi16(next, curr);
+      __m128i curb = _mm_add_epi16(curs, bias);
+      __m128i even = _mm_add_epi16(prvd, curb);
+      __m128i odd  = _mm_add_epi16(nxtd, curb);
+
+      // interleave even and odd pixels, then undo scaling.
+      __m128i int0 = _mm_unpacklo_epi16(even, odd);
+      __m128i int1 = _mm_unpackhi_epi16(even, odd);
+      __m128i de0  = _mm_srli_epi16(int0, 4);
+      __m128i de1  = _mm_srli_epi16(int1, 4);
+
+      // pack and write output
+      __m128i outv = _mm_packus_epi16(de0, de1);
+      _mm_storeu_si128((__m128i *) (out + i*2), outv);
+#elif defined(STBI_NEON)
+      // load and perform the vertical filtering pass
+      // this uses 3*x + y = 4*x + (y - x)
+      uint8x8_t farb  = vld1_u8(in_far + i);
+      uint8x8_t nearb = vld1_u8(in_near + i);
+      int16x8_t diff  = vreinterpretq_s16_u16(vsubl_u8(farb, nearb));
+      int16x8_t nears = vreinterpretq_s16_u16(vshll_n_u8(nearb, 2));
+      int16x8_t curr  = vaddq_s16(nears, diff); // current row
+
+      // horizontal filter works the same based on shifted vers of current
+      // row. "prev" is current row shifted right by 1 pixel; we need to
+      // insert the previous pixel value (from t1).
+      // "next" is current row shifted left by 1 pixel, with first pixel
+      // of next block of 8 pixels added in.
+      int16x8_t prv0 = vextq_s16(curr, curr, 7);
+      int16x8_t nxt0 = vextq_s16(curr, curr, 1);
+      int16x8_t prev = vsetq_lane_s16(t1, prv0, 0);
+      int16x8_t next = vsetq_lane_s16(3*in_near[i+8] + in_far[i+8], nxt0, 7);
+
+      // horizontal filter, polyphase implementation since it's convenient:
+      // even pixels = 3*cur + prev = cur*4 + (prev - cur)
+      // odd  pixels = 3*cur + next = cur*4 + (next - cur)
+      // note the shared term.
+      int16x8_t curs = vshlq_n_s16(curr, 2);
+      int16x8_t prvd = vsubq_s16(prev, curr);
+      int16x8_t nxtd = vsubq_s16(next, curr);
+      int16x8_t even = vaddq_s16(curs, prvd);
+      int16x8_t odd  = vaddq_s16(curs, nxtd);
+
+      // undo scaling and round, then store with even/odd phases interleaved
+      uint8x8x2_t o;
+      o.val[0] = vqrshrun_n_s16(even, 4);
+      o.val[1] = vqrshrun_n_s16(odd,  4);
+      vst2_u8(out + i*2, o);
+#endif
+
+      // "previous" value for next iter
+      t1 = 3*in_near[i+7] + in_far[i+7];
+   }
+
+   t0 = t1;
+   t1 = 3*in_near[i] + in_far[i];
+   out[i*2] = stbi__div16(3*t1 + t0 + 8);
+
+   for (++i; i < w; ++i) {
+      t0 = t1;
+      t1 = 3*in_near[i]+in_far[i];
+      out[i*2-1] = stbi__div16(3*t0 + t1 + 8);
+      out[i*2  ] = stbi__div16(3*t1 + t0 + 8);
+   }
+   out[w*2-1] = stbi__div4(t1+2);
+
+   STBI_NOTUSED(hs);
+
+   return out;
+}
+#endif
+
+static stbi_uc *stbi__resample_row_generic(stbi_uc *out, stbi_uc *in_near, stbi_uc *in_far, int w, int hs)
+{
+   // resample with nearest-neighbor
+   int i,j;
+   STBI_NOTUSED(in_far);
+   for (i=0; i < w; ++i)
+      for (j=0; j < hs; ++j)
+         out[i*hs+j] = in_near[i];
+   return out;
+}
+
+// this is a reduced-precision calculation of YCbCr-to-RGB introduced
+// to make sure the code produces the same results in both SIMD and scalar
+#define stbi__float2fixed(x)  (((int) ((x) * 4096.0f + 0.5f)) << 8)
+static void stbi__YCbCr_to_RGB_row(stbi_uc *out, const stbi_uc *y, const stbi_uc *pcb, const stbi_uc *pcr, int count, int step)
+{
+   int i;
+   for (i=0; i < count; ++i) {
+      int y_fixed = (y[i] << 20) + (1<<19); // rounding
+      int r,g,b;
+      int cr = pcr[i] - 128;
+      int cb = pcb[i] - 128;
+      r = y_fixed +  cr* stbi__float2fixed(1.40200f);
+      g = y_fixed + (cr*-stbi__float2fixed(0.71414f)) + ((cb*-stbi__float2fixed(0.34414f)) & 0xffff0000);
+      b = y_fixed                                     +   cb* stbi__float2fixed(1.77200f);
+      r >>= 20;
+      g >>= 20;
+      b >>= 20;
+      if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
+      if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
+      if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
+      out[0] = (stbi_uc)r;
+      out[1] = (stbi_uc)g;
+      out[2] = (stbi_uc)b;
+      out[3] = 255;
+      out += step;
+   }
+}
+
+#if defined(STBI_SSE2) || defined(STBI_NEON)
+static void stbi__YCbCr_to_RGB_simd(stbi_uc *out, stbi_uc const *y, stbi_uc const *pcb, stbi_uc const *pcr, int count, int step)
+{
+   int i = 0;
+
+#ifdef STBI_SSE2
+   // step == 3 is pretty ugly on the final interleave, and i'm not convinced
+   // it's useful in practice (you wouldn't use it for textures, for example).
+   // so just accelerate step == 4 case.
+   if (step == 4) {
+      // this is a fairly straightforward implementation and not super-optimized.
+      __m128i signflip  = _mm_set1_epi8(-0x80);
+      __m128i cr_const0 = _mm_set1_epi16(   (short) ( 1.40200f*4096.0f+0.5f));
+      __m128i cr_const1 = _mm_set1_epi16( - (short) ( 0.71414f*4096.0f+0.5f));
+      __m128i cb_const0 = _mm_set1_epi16( - (short) ( 0.34414f*4096.0f+0.5f));
+      __m128i cb_const1 = _mm_set1_epi16(   (short) ( 1.77200f*4096.0f+0.5f));
+      __m128i y_bias = _mm_set1_epi8((char) (unsigned char) 128);
+      __m128i xw = _mm_set1_epi16(255); // alpha channel
+
+      for (; i+7 < count; i += 8) {
+         // load
+         __m128i y_bytes = _mm_loadl_epi64((__m128i *) (y+i));
+         __m128i cr_bytes = _mm_loadl_epi64((__m128i *) (pcr+i));
+         __m128i cb_bytes = _mm_loadl_epi64((__m128i *) (pcb+i));
+         __m128i cr_biased = _mm_xor_si128(cr_bytes, signflip); // -128
+         __m128i cb_biased = _mm_xor_si128(cb_bytes, signflip); // -128
+
+         // unpack to short (and left-shift cr, cb by 8)
+         __m128i yw  = _mm_unpacklo_epi8(y_bias, y_bytes);
+         __m128i crw = _mm_unpacklo_epi8(_mm_setzero_si128(), cr_biased);
+         __m128i cbw = _mm_unpacklo_epi8(_mm_setzero_si128(), cb_biased);
+
+         // color transform
+         __m128i yws = _mm_srli_epi16(yw, 4);
+         __m128i cr0 = _mm_mulhi_epi16(cr_const0, crw);
+         __m128i cb0 = _mm_mulhi_epi16(cb_const0, cbw);
+         __m128i cb1 = _mm_mulhi_epi16(cbw, cb_const1);
+         __m128i cr1 = _mm_mulhi_epi16(crw, cr_const1);
+         __m128i rws = _mm_add_epi16(cr0, yws);
+         __m128i gwt = _mm_add_epi16(cb0, yws);
+         __m128i bws = _mm_add_epi16(yws, cb1);
+         __m128i gws = _mm_add_epi16(gwt, cr1);
+
+         // descale
+         __m128i rw = _mm_srai_epi16(rws, 4);
+         __m128i bw = _mm_srai_epi16(bws, 4);
+         __m128i gw = _mm_srai_epi16(gws, 4);
+
+         // back to byte, set up for transpose
+         __m128i brb = _mm_packus_epi16(rw, bw);
+         __m128i gxb = _mm_packus_epi16(gw, xw);
+
+         // transpose to interleave channels
+         __m128i t0 = _mm_unpacklo_epi8(brb, gxb);
+         __m128i t1 = _mm_unpackhi_epi8(brb, gxb);
+         __m128i o0 = _mm_unpacklo_epi16(t0, t1);
+         __m128i o1 = _mm_unpackhi_epi16(t0, t1);
+
+         // store
+         _mm_storeu_si128((__m128i *) (out + 0), o0);
+         _mm_storeu_si128((__m128i *) (out + 16), o1);
+         out += 32;
+      }
+   }
+#endif
+
+#ifdef STBI_NEON
+   // in this version, step=3 support would be easy to add. but is there demand?
+   if (step == 4) {
+      // this is a fairly straightforward implementation and not super-optimized.
+      uint8x8_t signflip = vdup_n_u8(0x80);
+      int16x8_t cr_const0 = vdupq_n_s16(   (short) ( 1.40200f*4096.0f+0.5f));
+      int16x8_t cr_const1 = vdupq_n_s16( - (short) ( 0.71414f*4096.0f+0.5f));
+      int16x8_t cb_const0 = vdupq_n_s16( - (short) ( 0.34414f*4096.0f+0.5f));
+      int16x8_t cb_const1 = vdupq_n_s16(   (short) ( 1.77200f*4096.0f+0.5f));
+
+      for (; i+7 < count; i += 8) {
+         // load
+         uint8x8_t y_bytes  = vld1_u8(y + i);
+         uint8x8_t cr_bytes = vld1_u8(pcr + i);
+         uint8x8_t cb_bytes = vld1_u8(pcb + i);
+         int8x8_t cr_biased = vreinterpret_s8_u8(vsub_u8(cr_bytes, signflip));
+         int8x8_t cb_biased = vreinterpret_s8_u8(vsub_u8(cb_bytes, signflip));
+
+         // expand to s16
+         int16x8_t yws = vreinterpretq_s16_u16(vshll_n_u8(y_bytes, 4));
+         int16x8_t crw = vshll_n_s8(cr_biased, 7);
+         int16x8_t cbw = vshll_n_s8(cb_biased, 7);
+
+         // color transform
+         int16x8_t cr0 = vqdmulhq_s16(crw, cr_const0);
+         int16x8_t cb0 = vqdmulhq_s16(cbw, cb_const0);
+         int16x8_t cr1 = vqdmulhq_s16(crw, cr_const1);
+         int16x8_t cb1 = vqdmulhq_s16(cbw, cb_const1);
+         int16x8_t rws = vaddq_s16(yws, cr0);
+         int16x8_t gws = vaddq_s16(vaddq_s16(yws, cb0), cr1);
+         int16x8_t bws = vaddq_s16(yws, cb1);
+
+         // undo scaling, round, convert to byte
+         uint8x8x4_t o;
+         o.val[0] = vqrshrun_n_s16(rws, 4);
+         o.val[1] = vqrshrun_n_s16(gws, 4);
+         o.val[2] = vqrshrun_n_s16(bws, 4);
+         o.val[3] = vdup_n_u8(255);
+
+         // store, interleaving r/g/b/a
+         vst4_u8(out, o);
+         out += 8*4;
+      }
+   }
+#endif
+
+   for (; i < count; ++i) {
+      int y_fixed = (y[i] << 20) + (1<<19); // rounding
+      int r,g,b;
+      int cr = pcr[i] - 128;
+      int cb = pcb[i] - 128;
+      r = y_fixed + cr* stbi__float2fixed(1.40200f);
+      g = y_fixed + cr*-stbi__float2fixed(0.71414f) + ((cb*-stbi__float2fixed(0.34414f)) & 0xffff0000);
+      b = y_fixed                                   +   cb* stbi__float2fixed(1.77200f);
+      r >>= 20;
+      g >>= 20;
+      b >>= 20;
+      if ((unsigned) r > 255) { if (r < 0) r = 0; else r = 255; }
+      if ((unsigned) g > 255) { if (g < 0) g = 0; else g = 255; }
+      if ((unsigned) b > 255) { if (b < 0) b = 0; else b = 255; }
+      out[0] = (stbi_uc)r;
+      out[1] = (stbi_uc)g;
+      out[2] = (stbi_uc)b;
+      out[3] = 255;
+      out += step;
+   }
+}
+#endif
+
+// set up the kernels
+static void stbi__setup_jpeg(stbi__jpeg *j)
+{
+   j->idct_block_kernel = stbi__idct_block;
+   j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_row;
+   j->resample_row_hv_2_kernel = stbi__resample_row_hv_2;
+
+#ifdef STBI_SSE2
+   if (stbi__sse2_available()) {
+      j->idct_block_kernel = stbi__idct_simd;
+      j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd;
+      j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd;
+   }
+#endif
+
+#ifdef STBI_NEON
+   j->idct_block_kernel = stbi__idct_simd;
+   j->YCbCr_to_RGB_kernel = stbi__YCbCr_to_RGB_simd;
+   j->resample_row_hv_2_kernel = stbi__resample_row_hv_2_simd;
+#endif
+}
+
+// clean up the temporary component buffers
+static void stbi__cleanup_jpeg(stbi__jpeg *j)
+{
+   stbi__free_jpeg_components(j, j->s->img_n, 0);
+}
+
+typedef struct
+{
+   resample_row_func resample;
+   stbi_uc *line0,*line1;
+   int hs,vs;   // expansion factor in each axis
+   int w_lores; // horizontal pixels pre-expansion
+   int ystep;   // how far through vertical expansion we are
+   int ypos;    // which pre-expansion row we're on
+} stbi__resample;
+
+// fast 0..255 * 0..255 => 0..255 rounded multiplication
+static stbi_uc stbi__blinn_8x8(stbi_uc x, stbi_uc y)
+{
+   unsigned int t = x*y + 128;
+   return (stbi_uc) ((t + (t >>8)) >> 8);
+}
+
+static stbi_uc *load_jpeg_image(stbi__jpeg *z, int *out_x, int *out_y, int *comp, int req_comp)
+{
+   int n, decode_n, is_rgb;
+   z->s->img_n = 0; // make stbi__cleanup_jpeg safe
+
+   // validate req_comp
+   if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
+
+   // load a jpeg image from whichever source, but leave in YCbCr format
+   if (!stbi__decode_jpeg_image(z)) { stbi__cleanup_jpeg(z); return NULL; }
+
+   // determine actual number of components to generate
+   n = req_comp ? req_comp : z->s->img_n >= 3 ? 3 : 1;
+
+   is_rgb = z->s->img_n == 3 && (z->rgb == 3 || (z->app14_color_transform == 0 && !z->jfif));
+
+   if (z->s->img_n == 3 && n < 3 && !is_rgb)
+      decode_n = 1;
+   else
+      decode_n = z->s->img_n;
+
+   // resample and color-convert
+   {
+      int k;
+      unsigned int i,j;
+      stbi_uc *output;
+      stbi_uc *coutput[4];
+
+      stbi__resample res_comp[4];
+
+      for (k=0; k < decode_n; ++k) {
+         stbi__resample *r = &res_comp[k];
+
+         // allocate line buffer big enough for upsampling off the edges
+         // with upsample factor of 4
+         z->img_comp[k].linebuf = (stbi_uc *) stbi__malloc(z->s->img_x + 3);
+         if (!z->img_comp[k].linebuf) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); }
+
+         r->hs      = z->img_h_max / z->img_comp[k].h;
+         r->vs      = z->img_v_max / z->img_comp[k].v;
+         r->ystep   = r->vs >> 1;
+         r->w_lores = (z->s->img_x + r->hs-1) / r->hs;
+         r->ypos    = 0;
+         r->line0   = r->line1 = z->img_comp[k].data;
+
+         if      (r->hs == 1 && r->vs == 1) r->resample = resample_row_1;
+         else if (r->hs == 1 && r->vs == 2) r->resample = stbi__resample_row_v_2;
+         else if (r->hs == 2 && r->vs == 1) r->resample = stbi__resample_row_h_2;
+         else if (r->hs == 2 && r->vs == 2) r->resample = z->resample_row_hv_2_kernel;
+         else                               r->resample = stbi__resample_row_generic;
+      }
+
+      // can't error after this so, this is safe
+      output = (stbi_uc *) stbi__malloc_mad3(n, z->s->img_x, z->s->img_y, 1);
+      if (!output) { stbi__cleanup_jpeg(z); return stbi__errpuc("outofmem", "Out of memory"); }
+
+      // now go ahead and resample
+      for (j=0; j < z->s->img_y; ++j) {
+         stbi_uc *out = output + n * z->s->img_x * j;
+         for (k=0; k < decode_n; ++k) {
+            stbi__resample *r = &res_comp[k];
+            int y_bot = r->ystep >= (r->vs >> 1);
+            coutput[k] = r->resample(z->img_comp[k].linebuf,
+                                     y_bot ? r->line1 : r->line0,
+                                     y_bot ? r->line0 : r->line1,
+                                     r->w_lores, r->hs);
+            if (++r->ystep >= r->vs) {
+               r->ystep = 0;
+               r->line0 = r->line1;
+               if (++r->ypos < z->img_comp[k].y)
+                  r->line1 += z->img_comp[k].w2;
+            }
+         }
+         if (n >= 3) {
+            stbi_uc *y = coutput[0];
+            if (z->s->img_n == 3) {
+               if (is_rgb) {
+                  for (i=0; i < z->s->img_x; ++i) {
+                     out[0] = y[i];
+                     out[1] = coutput[1][i];
+                     out[2] = coutput[2][i];
+                     out[3] = 255;
+                     out += n;
+                  }
+               } else {
+                  z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
+               }
+            } else if (z->s->img_n == 4) {
+               if (z->app14_color_transform == 0) { // CMYK
+                  for (i=0; i < z->s->img_x; ++i) {
+                     stbi_uc m = coutput[3][i];
+                     out[0] = stbi__blinn_8x8(coutput[0][i], m);
+                     out[1] = stbi__blinn_8x8(coutput[1][i], m);
+                     out[2] = stbi__blinn_8x8(coutput[2][i], m);
+                     out[3] = 255;
+                     out += n;
+                  }
+               } else if (z->app14_color_transform == 2) { // YCCK
+                  z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
+                  for (i=0; i < z->s->img_x; ++i) {
+                     stbi_uc m = coutput[3][i];
+                     out[0] = stbi__blinn_8x8(255 - out[0], m);
+                     out[1] = stbi__blinn_8x8(255 - out[1], m);
+                     out[2] = stbi__blinn_8x8(255 - out[2], m);
+                     out += n;
+                  }
+               } else { // YCbCr + alpha?  Ignore the fourth channel for now
+                  z->YCbCr_to_RGB_kernel(out, y, coutput[1], coutput[2], z->s->img_x, n);
+               }
+            } else
+               for (i=0; i < z->s->img_x; ++i) {
+                  out[0] = out[1] = out[2] = y[i];
+                  out[3] = 255; // not used if n==3
+                  out += n;
+               }
+         } else {
+            if (is_rgb) {
+               if (n == 1)
+                  for (i=0; i < z->s->img_x; ++i)
+                     *out++ = stbi__compute_y(coutput[0][i], coutput[1][i], coutput[2][i]);
+               else {
+                  for (i=0; i < z->s->img_x; ++i, out += 2) {
+                     out[0] = stbi__compute_y(coutput[0][i], coutput[1][i], coutput[2][i]);
+                     out[1] = 255;
+                  }
+               }
+            } else if (z->s->img_n == 4 && z->app14_color_transform == 0) {
+               for (i=0; i < z->s->img_x; ++i) {
+                  stbi_uc m = coutput[3][i];
+                  stbi_uc r = stbi__blinn_8x8(coutput[0][i], m);
+                  stbi_uc g = stbi__blinn_8x8(coutput[1][i], m);
+                  stbi_uc b = stbi__blinn_8x8(coutput[2][i], m);
+                  out[0] = stbi__compute_y(r, g, b);
+                  out[1] = 255;
+                  out += n;
+               }
+            } else if (z->s->img_n == 4 && z->app14_color_transform == 2) {
+               for (i=0; i < z->s->img_x; ++i) {
+                  out[0] = stbi__blinn_8x8(255 - coutput[0][i], coutput[3][i]);
+                  out[1] = 255;
+                  out += n;
+               }
+            } else {
+               stbi_uc *y = coutput[0];
+               if (n == 1)
+                  for (i=0; i < z->s->img_x; ++i) out[i] = y[i];
+               else
+                  for (i=0; i < z->s->img_x; ++i) { *out++ = y[i]; *out++ = 255; }
+            }
+         }
+      }
+      stbi__cleanup_jpeg(z);
+      *out_x = z->s->img_x;
+      *out_y = z->s->img_y;
+      if (comp) *comp = z->s->img_n >= 3 ? 3 : 1; // report original components, not output
+      return output;
+   }
+}
+
+static void *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   unsigned char* result;
+   stbi__jpeg* j = (stbi__jpeg*) stbi__malloc(sizeof(stbi__jpeg));
+   STBI_NOTUSED(ri);
+   j->s = s;
+   stbi__setup_jpeg(j);
+   result = load_jpeg_image(j, x,y,comp,req_comp);
+   STBI_FREE(j);
+   return result;
+}
+
+static int stbi__jpeg_test(stbi__context *s)
+{
+   int r;
+   stbi__jpeg* j = (stbi__jpeg*)stbi__malloc(sizeof(stbi__jpeg));
+   j->s = s;
+   stbi__setup_jpeg(j);
+   r = stbi__decode_jpeg_header(j, STBI__SCAN_type);
+   stbi__rewind(s);
+   STBI_FREE(j);
+   return r;
+}
+
+static int stbi__jpeg_info_raw(stbi__jpeg *j, int *x, int *y, int *comp)
+{
+   if (!stbi__decode_jpeg_header(j, STBI__SCAN_header)) {
+      stbi__rewind( j->s );
+      return 0;
+   }
+   if (x) *x = j->s->img_x;
+   if (y) *y = j->s->img_y;
+   if (comp) *comp = j->s->img_n >= 3 ? 3 : 1;
+   return 1;
+}
+
+static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   int result;
+   stbi__jpeg* j = (stbi__jpeg*) (stbi__malloc(sizeof(stbi__jpeg)));
+   j->s = s;
+   result = stbi__jpeg_info_raw(j, x, y, comp);
+   STBI_FREE(j);
+   return result;
+}
+#endif
+
+// public domain zlib decode    v0.2  Sean Barrett 2006-11-18
+//    simple implementation
+//      - all input must be provided in an upfront buffer
+//      - all output is written to a single output buffer (can malloc/realloc)
+//    performance
+//      - fast huffman
+
+#ifndef STBI_NO_ZLIB
+
+// fast-way is faster to check than jpeg huffman, but slow way is slower
+#define STBI__ZFAST_BITS  9 // accelerate all cases in default tables
+#define STBI__ZFAST_MASK  ((1 << STBI__ZFAST_BITS) - 1)
+
+// zlib-style huffman encoding
+// (jpegs packs from left, zlib from right, so can't share code)
+typedef struct
+{
+   stbi__uint16 fast[1 << STBI__ZFAST_BITS];
+   stbi__uint16 firstcode[16];
+   int maxcode[17];
+   stbi__uint16 firstsymbol[16];
+   stbi_uc  size[288];
+   stbi__uint16 value[288];
+} stbi__zhuffman;
+
+stbi_inline static int stbi__bitreverse16(int n)
+{
+  n = ((n & 0xAAAA) >>  1) | ((n & 0x5555) << 1);
+  n = ((n & 0xCCCC) >>  2) | ((n & 0x3333) << 2);
+  n = ((n & 0xF0F0) >>  4) | ((n & 0x0F0F) << 4);
+  n = ((n & 0xFF00) >>  8) | ((n & 0x00FF) << 8);
+  return n;
+}
+
+stbi_inline static int stbi__bit_reverse(int v, int bits)
+{
+   STBI_ASSERT(bits <= 16);
+   // to bit reverse n bits, reverse 16 and shift
+   // e.g. 11 bits, bit reverse and shift away 5
+   return stbi__bitreverse16(v) >> (16-bits);
+}
+
+static int stbi__zbuild_huffman(stbi__zhuffman *z, const stbi_uc *sizelist, int num)
+{
+   int i,k=0;
+   int code, next_code[16], sizes[17];
+
+   // DEFLATE spec for generating codes
+   memset(sizes, 0, sizeof(sizes));
+   memset(z->fast, 0, sizeof(z->fast));
+   for (i=0; i < num; ++i)
+      ++sizes[sizelist[i]];
+   sizes[0] = 0;
+   for (i=1; i < 16; ++i)
+      if (sizes[i] > (1 << i))
+         return stbi__err("bad sizes", "Corrupt PNG");
+   code = 0;
+   for (i=1; i < 16; ++i) {
+      next_code[i] = code;
+      z->firstcode[i] = (stbi__uint16) code;
+      z->firstsymbol[i] = (stbi__uint16) k;
+      code = (code + sizes[i]);
+      if (sizes[i])
+         if (code-1 >= (1 << i)) return stbi__err("bad codelengths","Corrupt PNG");
+      z->maxcode[i] = code << (16-i); // preshift for inner loop
+      code <<= 1;
+      k += sizes[i];
+   }
+   z->maxcode[16] = 0x10000; // sentinel
+   for (i=0; i < num; ++i) {
+      int s = sizelist[i];
+      if (s) {
+         int c = next_code[s] - z->firstcode[s] + z->firstsymbol[s];
+         stbi__uint16 fastv = (stbi__uint16) ((s << 9) | i);
+         z->size [c] = (stbi_uc     ) s;
+         z->value[c] = (stbi__uint16) i;
+         if (s <= STBI__ZFAST_BITS) {
+            int j = stbi__bit_reverse(next_code[s],s);
+            while (j < (1 << STBI__ZFAST_BITS)) {
+               z->fast[j] = fastv;
+               j += (1 << s);
+            }
+         }
+         ++next_code[s];
+      }
+   }
+   return 1;
+}
+
+// zlib-from-memory implementation for PNG reading
+//    because PNG allows splitting the zlib stream arbitrarily,
+//    and it's annoying structurally to have PNG call ZLIB call PNG,
+//    we require PNG read all the IDATs and combine them into a single
+//    memory buffer
+
+typedef struct
+{
+   stbi_uc *zbuffer, *zbuffer_end;
+   int num_bits;
+   stbi__uint32 code_buffer;
+
+   char *zout;
+   char *zout_start;
+   char *zout_end;
+   int   z_expandable;
+
+   stbi__zhuffman z_length, z_distance;
+} stbi__zbuf;
+
+stbi_inline static stbi_uc stbi__zget8(stbi__zbuf *z)
+{
+   if (z->zbuffer >= z->zbuffer_end) return 0;
+   return *z->zbuffer++;
+}
+
+static void stbi__fill_bits(stbi__zbuf *z)
+{
+   do {
+      STBI_ASSERT(z->code_buffer < (1U << z->num_bits));
+      z->code_buffer |= (unsigned int) stbi__zget8(z) << z->num_bits;
+      z->num_bits += 8;
+   } while (z->num_bits <= 24);
+}
+
+stbi_inline static unsigned int stbi__zreceive(stbi__zbuf *z, int n)
+{
+   unsigned int k;
+   if (z->num_bits < n) stbi__fill_bits(z);
+   k = z->code_buffer & ((1 << n) - 1);
+   z->code_buffer >>= n;
+   z->num_bits -= n;
+   return k;
+}
+
+static int stbi__zhuffman_decode_slowpath(stbi__zbuf *a, stbi__zhuffman *z)
+{
+   int b,s,k;
+   // not resolved by fast table, so compute it the slow way
+   // use jpeg approach, which requires MSbits at top
+   k = stbi__bit_reverse(a->code_buffer, 16);
+   for (s=STBI__ZFAST_BITS+1; ; ++s)
+      if (k < z->maxcode[s])
+         break;
+   if (s == 16) return -1; // invalid code!
+   // code size is s, so:
+   b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s];
+   STBI_ASSERT(z->size[b] == s);
+   a->code_buffer >>= s;
+   a->num_bits -= s;
+   return z->value[b];
+}
+
+stbi_inline static int stbi__zhuffman_decode(stbi__zbuf *a, stbi__zhuffman *z)
+{
+   int b,s;
+   if (a->num_bits < 16) stbi__fill_bits(a);
+   b = z->fast[a->code_buffer & STBI__ZFAST_MASK];
+   if (b) {
+      s = b >> 9;
+      a->code_buffer >>= s;
+      a->num_bits -= s;
+      return b & 511;
+   }
+   return stbi__zhuffman_decode_slowpath(a, z);
+}
+
+static int stbi__zexpand(stbi__zbuf *z, char *zout, int n)  // need to make room for n bytes
+{
+   char *q;
+   int cur, limit, old_limit;
+   z->zout = zout;
+   if (!z->z_expandable) return stbi__err("output buffer limit","Corrupt PNG");
+   cur   = (int) (z->zout     - z->zout_start);
+   limit = old_limit = (int) (z->zout_end - z->zout_start);
+   while (cur + n > limit)
+      limit *= 2;
+   q = (char *) STBI_REALLOC_SIZED(z->zout_start, old_limit, limit);
+   STBI_NOTUSED(old_limit);
+   if (q == NULL) return stbi__err("outofmem", "Out of memory");
+   z->zout_start = q;
+   z->zout       = q + cur;
+   z->zout_end   = q + limit;
+   return 1;
+}
+
+static const int stbi__zlength_base[31] = {
+   3,4,5,6,7,8,9,10,11,13,
+   15,17,19,23,27,31,35,43,51,59,
+   67,83,99,115,131,163,195,227,258,0,0 };
+
+static const int stbi__zlength_extra[31]=
+{ 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 };
+
+static const int stbi__zdist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,
+257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
+
+static const int stbi__zdist_extra[32] =
+{ 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
+
+static int stbi__parse_huffman_block(stbi__zbuf *a)
+{
+   char *zout = a->zout;
+   for(;;) {
+      int z = stbi__zhuffman_decode(a, &a->z_length);
+      if (z < 256) {
+         if (z < 0) return stbi__err("bad huffman code","Corrupt PNG"); // error in huffman codes
+         if (zout >= a->zout_end) {
+            if (!stbi__zexpand(a, zout, 1)) return 0;
+            zout = a->zout;
+         }
+         *zout++ = (char) z;
+      } else {
+         stbi_uc *p;
+         int len,dist;
+         if (z == 256) {
+            a->zout = zout;
+            return 1;
+         }
+         z -= 257;
+         len = stbi__zlength_base[z];
+         if (stbi__zlength_extra[z]) len += stbi__zreceive(a, stbi__zlength_extra[z]);
+         z = stbi__zhuffman_decode(a, &a->z_distance);
+         if (z < 0) return stbi__err("bad huffman code","Corrupt PNG");
+         dist = stbi__zdist_base[z];
+         if (stbi__zdist_extra[z]) dist += stbi__zreceive(a, stbi__zdist_extra[z]);
+         if (zout - a->zout_start < dist) return stbi__err("bad dist","Corrupt PNG");
+         if (zout + len > a->zout_end) {
+            if (!stbi__zexpand(a, zout, len)) return 0;
+            zout = a->zout;
+         }
+         p = (stbi_uc *) (zout - dist);
+         if (dist == 1) { // run of one byte; common in images.
+            stbi_uc v = *p;
+            if (len) { do *zout++ = v; while (--len); }
+         } else {
+            if (len) { do *zout++ = *p++; while (--len); }
+         }
+      }
+   }
+}
+
+static int stbi__compute_huffman_codes(stbi__zbuf *a)
+{
+   static const stbi_uc length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 };
+   stbi__zhuffman z_codelength;
+   stbi_uc lencodes[286+32+137];//padding for maximum single op
+   stbi_uc codelength_sizes[19];
+   int i,n;
+
+   int hlit  = stbi__zreceive(a,5) + 257;
+   int hdist = stbi__zreceive(a,5) + 1;
+   int hclen = stbi__zreceive(a,4) + 4;
+   int ntot  = hlit + hdist;
+
+   memset(codelength_sizes, 0, sizeof(codelength_sizes));
+   for (i=0; i < hclen; ++i) {
+      int s = stbi__zreceive(a,3);
+      codelength_sizes[length_dezigzag[i]] = (stbi_uc) s;
+   }
+   if (!stbi__zbuild_huffman(&z_codelength, codelength_sizes, 19)) return 0;
+
+   n = 0;
+   while (n < ntot) {
+      int c = stbi__zhuffman_decode(a, &z_codelength);
+      if (c < 0 || c >= 19) return stbi__err("bad codelengths", "Corrupt PNG");
+      if (c < 16)
+         lencodes[n++] = (stbi_uc) c;
+      else {
+         stbi_uc fill = 0;
+         if (c == 16) {
+            c = stbi__zreceive(a,2)+3;
+            if (n == 0) return stbi__err("bad codelengths", "Corrupt PNG");
+            fill = lencodes[n-1];
+         } else if (c == 17)
+            c = stbi__zreceive(a,3)+3;
+         else {
+            STBI_ASSERT(c == 18);
+            c = stbi__zreceive(a,7)+11;
+         }
+         if (ntot - n < c) return stbi__err("bad codelengths", "Corrupt PNG");
+         memset(lencodes+n, fill, c);
+         n += c;
+      }
+   }
+   if (n != ntot) return stbi__err("bad codelengths","Corrupt PNG");
+   if (!stbi__zbuild_huffman(&a->z_length, lencodes, hlit)) return 0;
+   if (!stbi__zbuild_huffman(&a->z_distance, lencodes+hlit, hdist)) return 0;
+   return 1;
+}
+
+static int stbi__parse_uncompressed_block(stbi__zbuf *a)
+{
+   stbi_uc header[4];
+   int len,nlen,k;
+   if (a->num_bits & 7)
+      stbi__zreceive(a, a->num_bits & 7); // discard
+   // drain the bit-packed data into header
+   k = 0;
+   while (a->num_bits > 0) {
+      header[k++] = (stbi_uc) (a->code_buffer & 255); // suppress MSVC run-time check
+      a->code_buffer >>= 8;
+      a->num_bits -= 8;
+   }
+   STBI_ASSERT(a->num_bits == 0);
+   // now fill header the normal way
+   while (k < 4)
+      header[k++] = stbi__zget8(a);
+   len  = header[1] * 256 + header[0];
+   nlen = header[3] * 256 + header[2];
+   if (nlen != (len ^ 0xffff)) return stbi__err("zlib corrupt","Corrupt PNG");
+   if (a->zbuffer + len > a->zbuffer_end) return stbi__err("read past buffer","Corrupt PNG");
+   if (a->zout + len > a->zout_end)
+      if (!stbi__zexpand(a, a->zout, len)) return 0;
+   memcpy(a->zout, a->zbuffer, len);
+   a->zbuffer += len;
+   a->zout += len;
+   return 1;
+}
+
+static int stbi__parse_zlib_header(stbi__zbuf *a)
+{
+   int cmf   = stbi__zget8(a);
+   int cm    = cmf & 15;
+   /* int cinfo = cmf >> 4; */
+   int flg   = stbi__zget8(a);
+   if ((cmf*256+flg) % 31 != 0) return stbi__err("bad zlib header","Corrupt PNG"); // zlib spec
+   if (flg & 32) return stbi__err("no preset dict","Corrupt PNG"); // preset dictionary not allowed in png
+   if (cm != 8) return stbi__err("bad compression","Corrupt PNG"); // DEFLATE required for png
+   // window = 1 << (8 + cinfo)... but who cares, we fully buffer output
+   return 1;
+}
+
+static const stbi_uc stbi__zdefault_length[288] =
+{
+   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
+   8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+   9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+   9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+   9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
+   7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8
+};
+static const stbi_uc stbi__zdefault_distance[32] =
+{
+   5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5
+};
+/*
+Init algorithm:
+{
+   int i;   // use <= to match clearly with spec
+   for (i=0; i <= 143; ++i)     stbi__zdefault_length[i]   = 8;
+   for (   ; i <= 255; ++i)     stbi__zdefault_length[i]   = 9;
+   for (   ; i <= 279; ++i)     stbi__zdefault_length[i]   = 7;
+   for (   ; i <= 287; ++i)     stbi__zdefault_length[i]   = 8;
+
+   for (i=0; i <=  31; ++i)     stbi__zdefault_distance[i] = 5;
+}
+*/
+
+static int stbi__parse_zlib(stbi__zbuf *a, int parse_header)
+{
+   int final, type;
+   if (parse_header)
+      if (!stbi__parse_zlib_header(a)) return 0;
+   a->num_bits = 0;
+   a->code_buffer = 0;
+   do {
+      final = stbi__zreceive(a,1);
+      type = stbi__zreceive(a,2);
+      if (type == 0) {
+         if (!stbi__parse_uncompressed_block(a)) return 0;
+      } else if (type == 3) {
+         return 0;
+      } else {
+         if (type == 1) {
+            // use fixed code lengths
+            if (!stbi__zbuild_huffman(&a->z_length  , stbi__zdefault_length  , 288)) return 0;
+            if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance,  32)) return 0;
+         } else {
+            if (!stbi__compute_huffman_codes(a)) return 0;
+         }
+         if (!stbi__parse_huffman_block(a)) return 0;
+      }
+   } while (!final);
+   return 1;
+}
+
+static int stbi__do_zlib(stbi__zbuf *a, char *obuf, int olen, int exp, int parse_header)
+{
+   a->zout_start = obuf;
+   a->zout       = obuf;
+   a->zout_end   = obuf + olen;
+   a->z_expandable = exp;
+
+   return stbi__parse_zlib(a, parse_header);
+}
+
+STBIDEF char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen)
+{
+   stbi__zbuf a;
+   char *p = (char *) stbi__malloc(initial_size);
+   if (p == NULL) return NULL;
+   a.zbuffer = (stbi_uc *) buffer;
+   a.zbuffer_end = (stbi_uc *) buffer + len;
+   if (stbi__do_zlib(&a, p, initial_size, 1, 1)) {
+      if (outlen) *outlen = (int) (a.zout - a.zout_start);
+      return a.zout_start;
+   } else {
+      STBI_FREE(a.zout_start);
+      return NULL;
+   }
+}
+
+STBIDEF char *stbi_zlib_decode_malloc(char const *buffer, int len, int *outlen)
+{
+   return stbi_zlib_decode_malloc_guesssize(buffer, len, 16384, outlen);
+}
+
+STBIDEF char *stbi_zlib_decode_malloc_guesssize_headerflag(const char *buffer, int len, int initial_size, int *outlen, int parse_header)
+{
+   stbi__zbuf a;
+   char *p = (char *) stbi__malloc(initial_size);
+   if (p == NULL) return NULL;
+   a.zbuffer = (stbi_uc *) buffer;
+   a.zbuffer_end = (stbi_uc *) buffer + len;
+   if (stbi__do_zlib(&a, p, initial_size, 1, parse_header)) {
+      if (outlen) *outlen = (int) (a.zout - a.zout_start);
+      return a.zout_start;
+   } else {
+      STBI_FREE(a.zout_start);
+      return NULL;
+   }
+}
+
+STBIDEF int stbi_zlib_decode_buffer(char *obuffer, int olen, char const *ibuffer, int ilen)
+{
+   stbi__zbuf a;
+   a.zbuffer = (stbi_uc *) ibuffer;
+   a.zbuffer_end = (stbi_uc *) ibuffer + ilen;
+   if (stbi__do_zlib(&a, obuffer, olen, 0, 1))
+      return (int) (a.zout - a.zout_start);
+   else
+      return -1;
+}
+
+STBIDEF char *stbi_zlib_decode_noheader_malloc(char const *buffer, int len, int *outlen)
+{
+   stbi__zbuf a;
+   char *p = (char *) stbi__malloc(16384);
+   if (p == NULL) return NULL;
+   a.zbuffer = (stbi_uc *) buffer;
+   a.zbuffer_end = (stbi_uc *) buffer+len;
+   if (stbi__do_zlib(&a, p, 16384, 1, 0)) {
+      if (outlen) *outlen = (int) (a.zout - a.zout_start);
+      return a.zout_start;
+   } else {
+      STBI_FREE(a.zout_start);
+      return NULL;
+   }
+}
+
+STBIDEF int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen)
+{
+   stbi__zbuf a;
+   a.zbuffer = (stbi_uc *) ibuffer;
+   a.zbuffer_end = (stbi_uc *) ibuffer + ilen;
+   if (stbi__do_zlib(&a, obuffer, olen, 0, 0))
+      return (int) (a.zout - a.zout_start);
+   else
+      return -1;
+}
+#endif
+
+// public domain "baseline" PNG decoder   v0.10  Sean Barrett 2006-11-18
+//    simple implementation
+//      - only 8-bit samples
+//      - no CRC checking
+//      - allocates lots of intermediate memory
+//        - avoids problem of streaming data between subsystems
+//        - avoids explicit window management
+//    performance
+//      - uses stb_zlib, a PD zlib implementation with fast huffman decoding
+
+#ifndef STBI_NO_PNG
+typedef struct
+{
+   stbi__uint32 length;
+   stbi__uint32 type;
+} stbi__pngchunk;
+
+static stbi__pngchunk stbi__get_chunk_header(stbi__context *s)
+{
+   stbi__pngchunk c;
+   c.length = stbi__get32be(s);
+   c.type   = stbi__get32be(s);
+   return c;
+}
+
+static int stbi__check_png_header(stbi__context *s)
+{
+   static const stbi_uc png_sig[8] = { 137,80,78,71,13,10,26,10 };
+   int i;
+   for (i=0; i < 8; ++i)
+      if (stbi__get8(s) != png_sig[i]) return stbi__err("bad png sig","Not a PNG");
+   return 1;
+}
+
+typedef struct
+{
+   stbi__context *s;
+   stbi_uc *idata, *expanded, *out;
+   int depth;
+} stbi__png;
+
+
+enum {
+   STBI__F_none=0,
+   STBI__F_sub=1,
+   STBI__F_up=2,
+   STBI__F_avg=3,
+   STBI__F_paeth=4,
+   // synthetic filters used for first scanline to avoid needing a dummy row of 0s
+   STBI__F_avg_first,
+   STBI__F_paeth_first
+};
+
+static stbi_uc first_row_filter[5] =
+{
+   STBI__F_none,
+   STBI__F_sub,
+   STBI__F_none,
+   STBI__F_avg_first,
+   STBI__F_paeth_first
+};
+
+static int stbi__paeth(int a, int b, int c)
+{
+   int p = a + b - c;
+   int pa = abs(p-a);
+   int pb = abs(p-b);
+   int pc = abs(p-c);
+   if (pa <= pb && pa <= pc) return a;
+   if (pb <= pc) return b;
+   return c;
+}
+
+static const stbi_uc stbi__depth_scale_table[9] = { 0, 0xff, 0x55, 0, 0x11, 0,0,0, 0x01 };
+
+// create the png data from post-deflated data
+static int stbi__create_png_image_raw(stbi__png *a, stbi_uc *raw, stbi__uint32 raw_len, int out_n, stbi__uint32 x, stbi__uint32 y, int depth, int color)
+{
+   int bytes = (depth == 16? 2 : 1);
+   stbi__context *s = a->s;
+   stbi__uint32 i,j,stride = x*out_n*bytes;
+   stbi__uint32 img_len, img_width_bytes;
+   int k;
+   int img_n = s->img_n; // copy it into a local for later
+
+   int output_bytes = out_n*bytes;
+   int filter_bytes = img_n*bytes;
+   int width = x;
+
+   STBI_ASSERT(out_n == s->img_n || out_n == s->img_n+1);
+   a->out = (stbi_uc *) stbi__malloc_mad3(x, y, output_bytes, 0); // extra bytes to write off the end into
+   if (!a->out) return stbi__err("outofmem", "Out of memory");
+
+   if (!stbi__mad3sizes_valid(img_n, x, depth, 7)) return stbi__err("too large", "Corrupt PNG");
+   img_width_bytes = (((img_n * x * depth) + 7) >> 3);
+   img_len = (img_width_bytes + 1) * y;
+
+   // we used to check for exact match between raw_len and img_len on non-interlaced PNGs,
+   // but issue #276 reported a PNG in the wild that had extra data at the end (all zeros),
+   // so just check for raw_len < img_len always.
+   if (raw_len < img_len) return stbi__err("not enough pixels","Corrupt PNG");
+
+   for (j=0; j < y; ++j) {
+      stbi_uc *cur = a->out + stride*j;
+      stbi_uc *prior;
+      int filter = *raw++;
+
+      if (filter > 4)
+         return stbi__err("invalid filter","Corrupt PNG");
+
+      if (depth < 8) {
+         STBI_ASSERT(img_width_bytes <= x);
+         cur += x*out_n - img_width_bytes; // store output to the rightmost img_len bytes, so we can decode in place
+         filter_bytes = 1;
+         width = img_width_bytes;
+      }
+      prior = cur - stride; // bugfix: need to compute this after 'cur +=' computation above
+
+      // if first row, use special filter that doesn't sample previous row
+      if (j == 0) filter = first_row_filter[filter];
+
+      // handle first byte explicitly
+      for (k=0; k < filter_bytes; ++k) {
+         switch (filter) {
+            case STBI__F_none       : cur[k] = raw[k]; break;
+            case STBI__F_sub        : cur[k] = raw[k]; break;
+            case STBI__F_up         : cur[k] = STBI__BYTECAST(raw[k] + prior[k]); break;
+            case STBI__F_avg        : cur[k] = STBI__BYTECAST(raw[k] + (prior[k]>>1)); break;
+            case STBI__F_paeth      : cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(0,prior[k],0)); break;
+            case STBI__F_avg_first  : cur[k] = raw[k]; break;
+            case STBI__F_paeth_first: cur[k] = raw[k]; break;
+         }
+      }
+
+      if (depth == 8) {
+         if (img_n != out_n)
+            cur[img_n] = 255; // first pixel
+         raw += img_n;
+         cur += out_n;
+         prior += out_n;
+      } else if (depth == 16) {
+         if (img_n != out_n) {
+            cur[filter_bytes]   = 255; // first pixel top byte
+            cur[filter_bytes+1] = 255; // first pixel bottom byte
+         }
+         raw += filter_bytes;
+         cur += output_bytes;
+         prior += output_bytes;
+      } else {
+         raw += 1;
+         cur += 1;
+         prior += 1;
+      }
+
+      // this is a little gross, so that we don't switch per-pixel or per-component
+      if (depth < 8 || img_n == out_n) {
+         int nk = (width - 1)*filter_bytes;
+         #define STBI__CASE(f) \
+             case f:     \
+                for (k=0; k < nk; ++k)
+         switch (filter) {
+            // "none" filter turns into a memcpy here; make that explicit.
+            case STBI__F_none:         memcpy(cur, raw, nk); break;
+            STBI__CASE(STBI__F_sub)          { cur[k] = STBI__BYTECAST(raw[k] + cur[k-filter_bytes]); } break;
+            STBI__CASE(STBI__F_up)           { cur[k] = STBI__BYTECAST(raw[k] + prior[k]); } break;
+            STBI__CASE(STBI__F_avg)          { cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k-filter_bytes])>>1)); } break;
+            STBI__CASE(STBI__F_paeth)        { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],prior[k],prior[k-filter_bytes])); } break;
+            STBI__CASE(STBI__F_avg_first)    { cur[k] = STBI__BYTECAST(raw[k] + (cur[k-filter_bytes] >> 1)); } break;
+            STBI__CASE(STBI__F_paeth_first)  { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k-filter_bytes],0,0)); } break;
+         }
+         #undef STBI__CASE
+         raw += nk;
+      } else {
+         STBI_ASSERT(img_n+1 == out_n);
+         #define STBI__CASE(f) \
+             case f:     \
+                for (i=x-1; i >= 1; --i, cur[filter_bytes]=255,raw+=filter_bytes,cur+=output_bytes,prior+=output_bytes) \
+                   for (k=0; k < filter_bytes; ++k)
+         switch (filter) {
+            STBI__CASE(STBI__F_none)         { cur[k] = raw[k]; } break;
+            STBI__CASE(STBI__F_sub)          { cur[k] = STBI__BYTECAST(raw[k] + cur[k- output_bytes]); } break;
+            STBI__CASE(STBI__F_up)           { cur[k] = STBI__BYTECAST(raw[k] + prior[k]); } break;
+            STBI__CASE(STBI__F_avg)          { cur[k] = STBI__BYTECAST(raw[k] + ((prior[k] + cur[k- output_bytes])>>1)); } break;
+            STBI__CASE(STBI__F_paeth)        { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],prior[k],prior[k- output_bytes])); } break;
+            STBI__CASE(STBI__F_avg_first)    { cur[k] = STBI__BYTECAST(raw[k] + (cur[k- output_bytes] >> 1)); } break;
+            STBI__CASE(STBI__F_paeth_first)  { cur[k] = STBI__BYTECAST(raw[k] + stbi__paeth(cur[k- output_bytes],0,0)); } break;
+         }
+         #undef STBI__CASE
+
+         // the loop above sets the high byte of the pixels' alpha, but for
+         // 16 bit png files we also need the low byte set. we'll do that here.
+         if (depth == 16) {
+            cur = a->out + stride*j; // start at the beginning of the row again
+            for (i=0; i < x; ++i,cur+=output_bytes) {
+               cur[filter_bytes+1] = 255;
+            }
+         }
+      }
+   }
+
+   // we make a separate pass to expand bits to pixels; for performance,
+   // this could run two scanlines behind the above code, so it won't
+   // intefere with filtering but will still be in the cache.
+   if (depth < 8) {
+      for (j=0; j < y; ++j) {
+         stbi_uc *cur = a->out + stride*j;
+         stbi_uc *in  = a->out + stride*j + x*out_n - img_width_bytes;
+         // unpack 1/2/4-bit into a 8-bit buffer. allows us to keep the common 8-bit path optimal at minimal cost for 1/2/4-bit
+         // png guarante byte alignment, if width is not multiple of 8/4/2 we'll decode dummy trailing data that will be skipped in the later loop
+         stbi_uc scale = (color == 0) ? stbi__depth_scale_table[depth] : 1; // scale grayscale values to 0..255 range
+
+         // note that the final byte might overshoot and write more data than desired.
+         // we can allocate enough data that this never writes out of memory, but it
+         // could also overwrite the next scanline. can it overwrite non-empty data
+         // on the next scanline? yes, consider 1-pixel-wide scanlines with 1-bit-per-pixel.
+         // so we need to explicitly clamp the final ones
+
+         if (depth == 4) {
+            for (k=x*img_n; k >= 2; k-=2, ++in) {
+               *cur++ = scale * ((*in >> 4)       );
+               *cur++ = scale * ((*in     ) & 0x0f);
+            }
+            if (k > 0) *cur++ = scale * ((*in >> 4)       );
+         } else if (depth == 2) {
+            for (k=x*img_n; k >= 4; k-=4, ++in) {
+               *cur++ = scale * ((*in >> 6)       );
+               *cur++ = scale * ((*in >> 4) & 0x03);
+               *cur++ = scale * ((*in >> 2) & 0x03);
+               *cur++ = scale * ((*in     ) & 0x03);
+            }
+            if (k > 0) *cur++ = scale * ((*in >> 6)       );
+            if (k > 1) *cur++ = scale * ((*in >> 4) & 0x03);
+            if (k > 2) *cur++ = scale * ((*in >> 2) & 0x03);
+         } else if (depth == 1) {
+            for (k=x*img_n; k >= 8; k-=8, ++in) {
+               *cur++ = scale * ((*in >> 7)       );
+               *cur++ = scale * ((*in >> 6) & 0x01);
+               *cur++ = scale * ((*in >> 5) & 0x01);
+               *cur++ = scale * ((*in >> 4) & 0x01);
+               *cur++ = scale * ((*in >> 3) & 0x01);
+               *cur++ = scale * ((*in >> 2) & 0x01);
+               *cur++ = scale * ((*in >> 1) & 0x01);
+               *cur++ = scale * ((*in     ) & 0x01);
+            }
+            if (k > 0) *cur++ = scale * ((*in >> 7)       );
+            if (k > 1) *cur++ = scale * ((*in >> 6) & 0x01);
+            if (k > 2) *cur++ = scale * ((*in >> 5) & 0x01);
+            if (k > 3) *cur++ = scale * ((*in >> 4) & 0x01);
+            if (k > 4) *cur++ = scale * ((*in >> 3) & 0x01);
+            if (k > 5) *cur++ = scale * ((*in >> 2) & 0x01);
+            if (k > 6) *cur++ = scale * ((*in >> 1) & 0x01);
+         }
+         if (img_n != out_n) {
+            int q;
+            // insert alpha = 255
+            cur = a->out + stride*j;
+            if (img_n == 1) {
+               for (q=x-1; q >= 0; --q) {
+                  cur[q*2+1] = 255;
+                  cur[q*2+0] = cur[q];
+               }
+            } else {
+               STBI_ASSERT(img_n == 3);
+               for (q=x-1; q >= 0; --q) {
+                  cur[q*4+3] = 255;
+                  cur[q*4+2] = cur[q*3+2];
+                  cur[q*4+1] = cur[q*3+1];
+                  cur[q*4+0] = cur[q*3+0];
+               }
+            }
+         }
+      }
+   } else if (depth == 16) {
+      // force the image data from big-endian to platform-native.
+      // this is done in a separate pass due to the decoding relying
+      // on the data being untouched, but could probably be done
+      // per-line during decode if care is taken.
+      stbi_uc *cur = a->out;
+      stbi__uint16 *cur16 = (stbi__uint16*)cur;
+
+      for(i=0; i < x*y*out_n; ++i,cur16++,cur+=2) {
+         *cur16 = (cur[0] << 8) | cur[1];
+      }
+   }
+
+   return 1;
+}
+
+static int stbi__create_png_image(stbi__png *a, stbi_uc *image_data, stbi__uint32 image_data_len, int out_n, int depth, int color, int interlaced)
+{
+   int bytes = (depth == 16 ? 2 : 1);
+   int out_bytes = out_n * bytes;
+   stbi_uc *final;
+   int p;
+   if (!interlaced)
+      return stbi__create_png_image_raw(a, image_data, image_data_len, out_n, a->s->img_x, a->s->img_y, depth, color);
+
+   // de-interlacing
+   final = (stbi_uc *) stbi__malloc_mad3(a->s->img_x, a->s->img_y, out_bytes, 0);
+   for (p=0; p < 7; ++p) {
+      int xorig[] = { 0,4,0,2,0,1,0 };
+      int yorig[] = { 0,0,4,0,2,0,1 };
+      int xspc[]  = { 8,8,4,4,2,2,1 };
+      int yspc[]  = { 8,8,8,4,4,2,2 };
+      int i,j,x,y;
+      // pass1_x[4] = 0, pass1_x[5] = 1, pass1_x[12] = 1
+      x = (a->s->img_x - xorig[p] + xspc[p]-1) / xspc[p];
+      y = (a->s->img_y - yorig[p] + yspc[p]-1) / yspc[p];
+      if (x && y) {
+         stbi__uint32 img_len = ((((a->s->img_n * x * depth) + 7) >> 3) + 1) * y;
+         if (!stbi__create_png_image_raw(a, image_data, image_data_len, out_n, x, y, depth, color)) {
+            STBI_FREE(final);
+            return 0;
+         }
+         for (j=0; j < y; ++j) {
+            for (i=0; i < x; ++i) {
+               int out_y = j*yspc[p]+yorig[p];
+               int out_x = i*xspc[p]+xorig[p];
+               memcpy(final + out_y*a->s->img_x*out_bytes + out_x*out_bytes,
+                      a->out + (j*x+i)*out_bytes, out_bytes);
+            }
+         }
+         STBI_FREE(a->out);
+         image_data += img_len;
+         image_data_len -= img_len;
+      }
+   }
+   a->out = final;
+
+   return 1;
+}
+
+static int stbi__compute_transparency(stbi__png *z, stbi_uc tc[3], int out_n)
+{
+   stbi__context *s = z->s;
+   stbi__uint32 i, pixel_count = s->img_x * s->img_y;
+   stbi_uc *p = z->out;
+
+   // compute color-based transparency, assuming we've
+   // already got 255 as the alpha value in the output
+   STBI_ASSERT(out_n == 2 || out_n == 4);
+
+   if (out_n == 2) {
+      for (i=0; i < pixel_count; ++i) {
+         p[1] = (p[0] == tc[0] ? 0 : 255);
+         p += 2;
+      }
+   } else {
+      for (i=0; i < pixel_count; ++i) {
+         if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2])
+            p[3] = 0;
+         p += 4;
+      }
+   }
+   return 1;
+}
+
+static int stbi__compute_transparency16(stbi__png *z, stbi__uint16 tc[3], int out_n)
+{
+   stbi__context *s = z->s;
+   stbi__uint32 i, pixel_count = s->img_x * s->img_y;
+   stbi__uint16 *p = (stbi__uint16*) z->out;
+
+   // compute color-based transparency, assuming we've
+   // already got 65535 as the alpha value in the output
+   STBI_ASSERT(out_n == 2 || out_n == 4);
+
+   if (out_n == 2) {
+      for (i = 0; i < pixel_count; ++i) {
+         p[1] = (p[0] == tc[0] ? 0 : 65535);
+         p += 2;
+      }
+   } else {
+      for (i = 0; i < pixel_count; ++i) {
+         if (p[0] == tc[0] && p[1] == tc[1] && p[2] == tc[2])
+            p[3] = 0;
+         p += 4;
+      }
+   }
+   return 1;
+}
+
+static int stbi__expand_png_palette(stbi__png *a, stbi_uc *palette, int len, int pal_img_n)
+{
+   stbi__uint32 i, pixel_count = a->s->img_x * a->s->img_y;
+   stbi_uc *p, *temp_out, *orig = a->out;
+
+   p = (stbi_uc *) stbi__malloc_mad2(pixel_count, pal_img_n, 0);
+   if (p == NULL) return stbi__err("outofmem", "Out of memory");
+
+   // between here and free(out) below, exitting would leak
+   temp_out = p;
+
+   if (pal_img_n == 3) {
+      for (i=0; i < pixel_count; ++i) {
+         int n = orig[i]*4;
+         p[0] = palette[n  ];
+         p[1] = palette[n+1];
+         p[2] = palette[n+2];
+         p += 3;
+      }
+   } else {
+      for (i=0; i < pixel_count; ++i) {
+         int n = orig[i]*4;
+         p[0] = palette[n  ];
+         p[1] = palette[n+1];
+         p[2] = palette[n+2];
+         p[3] = palette[n+3];
+         p += 4;
+      }
+   }
+   STBI_FREE(a->out);
+   a->out = temp_out;
+
+   STBI_NOTUSED(len);
+
+   return 1;
+}
+
+static int stbi__unpremultiply_on_load = 0;
+static int stbi__de_iphone_flag = 0;
+
+STBIDEF void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply)
+{
+   stbi__unpremultiply_on_load = flag_true_if_should_unpremultiply;
+}
+
+STBIDEF void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert)
+{
+   stbi__de_iphone_flag = flag_true_if_should_convert;
+}
+
+static void stbi__de_iphone(stbi__png *z)
+{
+   stbi__context *s = z->s;
+   stbi__uint32 i, pixel_count = s->img_x * s->img_y;
+   stbi_uc *p = z->out;
+
+   if (s->img_out_n == 3) {  // convert bgr to rgb
+      for (i=0; i < pixel_count; ++i) {
+         stbi_uc t = p[0];
+         p[0] = p[2];
+         p[2] = t;
+         p += 3;
+      }
+   } else {
+      STBI_ASSERT(s->img_out_n == 4);
+      if (stbi__unpremultiply_on_load) {
+         // convert bgr to rgb and unpremultiply
+         for (i=0; i < pixel_count; ++i) {
+            stbi_uc a = p[3];
+            stbi_uc t = p[0];
+            if (a) {
+               stbi_uc half = a / 2;
+               p[0] = (p[2] * 255 + half) / a;
+               p[1] = (p[1] * 255 + half) / a;
+               p[2] = ( t   * 255 + half) / a;
+            } else {
+               p[0] = p[2];
+               p[2] = t;
+            }
+            p += 4;
+         }
+      } else {
+         // convert bgr to rgb
+         for (i=0; i < pixel_count; ++i) {
+            stbi_uc t = p[0];
+            p[0] = p[2];
+            p[2] = t;
+            p += 4;
+         }
+      }
+   }
+}
+
+#define STBI__PNG_TYPE(a,b,c,d)  (((unsigned) (a) << 24) + ((unsigned) (b) << 16) + ((unsigned) (c) << 8) + (unsigned) (d))
+
+static int stbi__parse_png_file(stbi__png *z, int scan, int req_comp)
+{
+   stbi_uc palette[1024], pal_img_n=0;
+   stbi_uc has_trans=0, tc[3]={0};
+   stbi__uint16 tc16[3];
+   stbi__uint32 ioff=0, idata_limit=0, i, pal_len=0;
+   int first=1,k,interlace=0, color=0, is_iphone=0;
+   stbi__context *s = z->s;
+
+   z->expanded = NULL;
+   z->idata = NULL;
+   z->out = NULL;
+
+   if (!stbi__check_png_header(s)) return 0;
+
+   if (scan == STBI__SCAN_type) return 1;
+
+   for (;;) {
+      stbi__pngchunk c = stbi__get_chunk_header(s);
+      switch (c.type) {
+         case STBI__PNG_TYPE('C','g','B','I'):
+            is_iphone = 1;
+            stbi__skip(s, c.length);
+            break;
+         case STBI__PNG_TYPE('I','H','D','R'): {
+            int comp,filter;
+            if (!first) return stbi__err("multiple IHDR","Corrupt PNG");
+            first = 0;
+            if (c.length != 13) return stbi__err("bad IHDR len","Corrupt PNG");
+            s->img_x = stbi__get32be(s); if (s->img_x > (1 << 24)) return stbi__err("too large","Very large image (corrupt?)");
+            s->img_y = stbi__get32be(s); if (s->img_y > (1 << 24)) return stbi__err("too large","Very large image (corrupt?)");
+            z->depth = stbi__get8(s);  if (z->depth != 1 && z->depth != 2 && z->depth != 4 && z->depth != 8 && z->depth != 16)  return stbi__err("1/2/4/8/16-bit only","PNG not supported: 1/2/4/8/16-bit only");
+            color = stbi__get8(s);  if (color > 6)         return stbi__err("bad ctype","Corrupt PNG");
+            if (color == 3 && z->depth == 16)                  return stbi__err("bad ctype","Corrupt PNG");
+            if (color == 3) pal_img_n = 3; else if (color & 1) return stbi__err("bad ctype","Corrupt PNG");
+            comp  = stbi__get8(s);  if (comp) return stbi__err("bad comp method","Corrupt PNG");
+            filter= stbi__get8(s);  if (filter) return stbi__err("bad filter method","Corrupt PNG");
+            interlace = stbi__get8(s); if (interlace>1) return stbi__err("bad interlace method","Corrupt PNG");
+            if (!s->img_x || !s->img_y) return stbi__err("0-pixel image","Corrupt PNG");
+            if (!pal_img_n) {
+               s->img_n = (color & 2 ? 3 : 1) + (color & 4 ? 1 : 0);
+               if ((1 << 30) / s->img_x / s->img_n < s->img_y) return stbi__err("too large", "Image too large to decode");
+               if (scan == STBI__SCAN_header) return 1;
+            } else {
+               // if paletted, then pal_n is our final components, and
+               // img_n is # components to decompress/filter.
+               s->img_n = 1;
+               if ((1 << 30) / s->img_x / 4 < s->img_y) return stbi__err("too large","Corrupt PNG");
+               // if SCAN_header, have to scan to see if we have a tRNS
+            }
+            break;
+         }
+
+         case STBI__PNG_TYPE('P','L','T','E'):  {
+            if (first) return stbi__err("first not IHDR", "Corrupt PNG");
+            if (c.length > 256*3) return stbi__err("invalid PLTE","Corrupt PNG");
+            pal_len = c.length / 3;
+            if (pal_len * 3 != c.length) return stbi__err("invalid PLTE","Corrupt PNG");
+            for (i=0; i < pal_len; ++i) {
+               palette[i*4+0] = stbi__get8(s);
+               palette[i*4+1] = stbi__get8(s);
+               palette[i*4+2] = stbi__get8(s);
+               palette[i*4+3] = 255;
+            }
+            break;
+         }
+
+         case STBI__PNG_TYPE('t','R','N','S'): {
+            if (first) return stbi__err("first not IHDR", "Corrupt PNG");
+            if (z->idata) return stbi__err("tRNS after IDAT","Corrupt PNG");
+            if (pal_img_n) {
+               if (scan == STBI__SCAN_header) { s->img_n = 4; return 1; }
+               if (pal_len == 0) return stbi__err("tRNS before PLTE","Corrupt PNG");
+               if (c.length > pal_len) return stbi__err("bad tRNS len","Corrupt PNG");
+               pal_img_n = 4;
+               for (i=0; i < c.length; ++i)
+                  palette[i*4+3] = stbi__get8(s);
+            } else {
+               if (!(s->img_n & 1)) return stbi__err("tRNS with alpha","Corrupt PNG");
+               if (c.length != (stbi__uint32) s->img_n*2) return stbi__err("bad tRNS len","Corrupt PNG");
+               has_trans = 1;
+               if (z->depth == 16) {
+                  for (k = 0; k < s->img_n; ++k) tc16[k] = (stbi__uint16)stbi__get16be(s); // copy the values as-is
+               } else {
+                  for (k = 0; k < s->img_n; ++k) tc[k] = (stbi_uc)(stbi__get16be(s) & 255) * stbi__depth_scale_table[z->depth]; // non 8-bit images will be larger
+               }
+            }
+            break;
+         }
+
+         case STBI__PNG_TYPE('I','D','A','T'): {
+            if (first) return stbi__err("first not IHDR", "Corrupt PNG");
+            if (pal_img_n && !pal_len) return stbi__err("no PLTE","Corrupt PNG");
+            if (scan == STBI__SCAN_header) { s->img_n = pal_img_n; return 1; }
+            if ((int)(ioff + c.length) < (int)ioff) return 0;
+            if (ioff + c.length > idata_limit) {
+               stbi__uint32 idata_limit_old = idata_limit;
+               stbi_uc *p;
+               if (idata_limit == 0) idata_limit = c.length > 4096 ? c.length : 4096;
+               while (ioff + c.length > idata_limit)
+                  idata_limit *= 2;
+               STBI_NOTUSED(idata_limit_old);
+               p = (stbi_uc *) STBI_REALLOC_SIZED(z->idata, idata_limit_old, idata_limit); if (p == NULL) return stbi__err("outofmem", "Out of memory");
+               z->idata = p;
+            }
+            if (!stbi__getn(s, z->idata+ioff,c.length)) return stbi__err("outofdata","Corrupt PNG");
+            ioff += c.length;
+            break;
+         }
+
+         case STBI__PNG_TYPE('I','E','N','D'): {
+            stbi__uint32 raw_len, bpl;
+            if (first) return stbi__err("first not IHDR", "Corrupt PNG");
+            if (scan != STBI__SCAN_load) return 1;
+            if (z->idata == NULL) return stbi__err("no IDAT","Corrupt PNG");
+            // initial guess for decoded data size to avoid unnecessary reallocs
+            bpl = (s->img_x * z->depth + 7) / 8; // bytes per line, per component
+            raw_len = bpl * s->img_y * s->img_n /* pixels */ + s->img_y /* filter mode per row */;
+            z->expanded = (stbi_uc *) stbi_zlib_decode_malloc_guesssize_headerflag((char *) z->idata, ioff, raw_len, (int *) &raw_len, !is_iphone);
+            if (z->expanded == NULL) return 0; // zlib should set error
+            STBI_FREE(z->idata); z->idata = NULL;
+            if ((req_comp == s->img_n+1 && req_comp != 3 && !pal_img_n) || has_trans)
+               s->img_out_n = s->img_n+1;
+            else
+               s->img_out_n = s->img_n;
+            if (!stbi__create_png_image(z, z->expanded, raw_len, s->img_out_n, z->depth, color, interlace)) return 0;
+            if (has_trans) {
+               if (z->depth == 16) {
+                  if (!stbi__compute_transparency16(z, tc16, s->img_out_n)) return 0;
+               } else {
+                  if (!stbi__compute_transparency(z, tc, s->img_out_n)) return 0;
+               }
+            }
+            if (is_iphone && stbi__de_iphone_flag && s->img_out_n > 2)
+               stbi__de_iphone(z);
+            if (pal_img_n) {
+               // pal_img_n == 3 or 4
+               s->img_n = pal_img_n; // record the actual colors we had
+               s->img_out_n = pal_img_n;
+               if (req_comp >= 3) s->img_out_n = req_comp;
+               if (!stbi__expand_png_palette(z, palette, pal_len, s->img_out_n))
+                  return 0;
+            } else if (has_trans) {
+               // non-paletted image with tRNS -> source image has (constant) alpha
+               ++s->img_n;
+            }
+            STBI_FREE(z->expanded); z->expanded = NULL;
+            return 1;
+         }
+
+         default:
+            // if critical, fail
+            if (first) return stbi__err("first not IHDR", "Corrupt PNG");
+            if ((c.type & (1 << 29)) == 0) {
+               #ifndef STBI_NO_FAILURE_STRINGS
+               // not threadsafe
+               static char invalid_chunk[] = "XXXX PNG chunk not known";
+               invalid_chunk[0] = STBI__BYTECAST(c.type >> 24);
+               invalid_chunk[1] = STBI__BYTECAST(c.type >> 16);
+               invalid_chunk[2] = STBI__BYTECAST(c.type >>  8);
+               invalid_chunk[3] = STBI__BYTECAST(c.type >>  0);
+               #endif
+               return stbi__err(invalid_chunk, "PNG not supported: unknown PNG chunk type");
+            }
+            stbi__skip(s, c.length);
+            break;
+      }
+      // end of PNG chunk, read and skip CRC
+      stbi__get32be(s);
+   }
+}
+
+static void *stbi__do_png(stbi__png *p, int *x, int *y, int *n, int req_comp, stbi__result_info *ri)
+{
+   void *result=NULL;
+   if (req_comp < 0 || req_comp > 4) return stbi__errpuc("bad req_comp", "Internal error");
+   if (stbi__parse_png_file(p, STBI__SCAN_load, req_comp)) {
+      if (p->depth < 8)
+         ri->bits_per_channel = 8;
+      else
+         ri->bits_per_channel = p->depth;
+      result = p->out;
+      p->out = NULL;
+      if (req_comp && req_comp != p->s->img_out_n) {
+         if (ri->bits_per_channel == 8)
+            result = stbi__convert_format((unsigned char *) result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y);
+         else
+            result = stbi__convert_format16((stbi__uint16 *) result, p->s->img_out_n, req_comp, p->s->img_x, p->s->img_y);
+         p->s->img_out_n = req_comp;
+         if (result == NULL) return result;
+      }
+      *x = p->s->img_x;
+      *y = p->s->img_y;
+      if (n) *n = p->s->img_n;
+   }
+   STBI_FREE(p->out);      p->out      = NULL;
+   STBI_FREE(p->expanded); p->expanded = NULL;
+   STBI_FREE(p->idata);    p->idata    = NULL;
+
+   return result;
+}
+
+static void *stbi__png_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   stbi__png p;
+   p.s = s;
+   return stbi__do_png(&p, x,y,comp,req_comp, ri);
+}
+
+static int stbi__png_test(stbi__context *s)
+{
+   int r;
+   r = stbi__check_png_header(s);
+   stbi__rewind(s);
+   return r;
+}
+
+static int stbi__png_info_raw(stbi__png *p, int *x, int *y, int *comp)
+{
+   if (!stbi__parse_png_file(p, STBI__SCAN_header, 0)) {
+      stbi__rewind( p->s );
+      return 0;
+   }
+   if (x) *x = p->s->img_x;
+   if (y) *y = p->s->img_y;
+   if (comp) *comp = p->s->img_n;
+   return 1;
+}
+
+static int stbi__png_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   stbi__png p;
+   p.s = s;
+   return stbi__png_info_raw(&p, x, y, comp);
+}
+
+static int stbi__png_is16(stbi__context *s)
+{
+   stbi__png p;
+   p.s = s;
+   if (!stbi__png_info_raw(&p, NULL, NULL, NULL))
+	   return 0;
+   if (p.depth != 16) {
+      stbi__rewind(p.s);
+      return 0;
+   }
+   return 1;
+}
+#endif
+
+// Microsoft/Windows BMP image
+
+#ifndef STBI_NO_BMP
+static int stbi__bmp_test_raw(stbi__context *s)
+{
+   int r;
+   int sz;
+   if (stbi__get8(s) != 'B') return 0;
+   if (stbi__get8(s) != 'M') return 0;
+   stbi__get32le(s); // discard filesize
+   stbi__get16le(s); // discard reserved
+   stbi__get16le(s); // discard reserved
+   stbi__get32le(s); // discard data offset
+   sz = stbi__get32le(s);
+   r = (sz == 12 || sz == 40 || sz == 56 || sz == 108 || sz == 124);
+   return r;
+}
+
+static int stbi__bmp_test(stbi__context *s)
+{
+   int r = stbi__bmp_test_raw(s);
+   stbi__rewind(s);
+   return r;
+}
+
+
+// returns 0..31 for the highest set bit
+static int stbi__high_bit(unsigned int z)
+{
+   int n=0;
+   if (z == 0) return -1;
+   if (z >= 0x10000) { n += 16; z >>= 16; }
+   if (z >= 0x00100) { n +=  8; z >>=  8; }
+   if (z >= 0x00010) { n +=  4; z >>=  4; }
+   if (z >= 0x00004) { n +=  2; z >>=  2; }
+   if (z >= 0x00002) { n +=  1; z >>=  1; }
+   return n;
+}
+
+static int stbi__bitcount(unsigned int a)
+{
+   a = (a & 0x55555555) + ((a >>  1) & 0x55555555); // max 2
+   a = (a & 0x33333333) + ((a >>  2) & 0x33333333); // max 4
+   a = (a + (a >> 4)) & 0x0f0f0f0f; // max 8 per 4, now 8 bits
+   a = (a + (a >> 8)); // max 16 per 8 bits
+   a = (a + (a >> 16)); // max 32 per 8 bits
+   return a & 0xff;
+}
+
+// extract an arbitrarily-aligned N-bit value (N=bits)
+// from v, and then make it 8-bits long and fractionally
+// extend it to full full range.
+static int stbi__shiftsigned(unsigned int v, int shift, int bits)
+{
+   static unsigned int mul_table[9] = {
+      0,
+      0xff/*0b11111111*/, 0x55/*0b01010101*/, 0x49/*0b01001001*/, 0x11/*0b00010001*/,
+      0x21/*0b00100001*/, 0x41/*0b01000001*/, 0x81/*0b10000001*/, 0x01/*0b00000001*/,
+   };
+   static unsigned int shift_table[9] = {
+      0, 0,0,1,0,2,4,6,0,
+   };
+   if (shift < 0)
+      v <<= -shift;
+   else
+      v >>= shift;
+   STBI_ASSERT(v >= 0 && v < 256);
+   v >>= (8-bits);
+   STBI_ASSERT(bits >= 0 && bits <= 8);
+   return (int) ((unsigned) v * mul_table[bits]) >> shift_table[bits];
+}
+
+typedef struct
+{
+   int bpp, offset, hsz;
+   unsigned int mr,mg,mb,ma, all_a;
+} stbi__bmp_data;
+
+static void *stbi__bmp_parse_header(stbi__context *s, stbi__bmp_data *info)
+{
+   int hsz;
+   if (stbi__get8(s) != 'B' || stbi__get8(s) != 'M') return stbi__errpuc("not BMP", "Corrupt BMP");
+   stbi__get32le(s); // discard filesize
+   stbi__get16le(s); // discard reserved
+   stbi__get16le(s); // discard reserved
+   info->offset = stbi__get32le(s);
+   info->hsz = hsz = stbi__get32le(s);
+   info->mr = info->mg = info->mb = info->ma = 0;
+
+   if (hsz != 12 && hsz != 40 && hsz != 56 && hsz != 108 && hsz != 124) return stbi__errpuc("unknown BMP", "BMP type not supported: unknown");
+   if (hsz == 12) {
+      s->img_x = stbi__get16le(s);
+      s->img_y = stbi__get16le(s);
+   } else {
+      s->img_x = stbi__get32le(s);
+      s->img_y = stbi__get32le(s);
+   }
+   if (stbi__get16le(s) != 1) return stbi__errpuc("bad BMP", "bad BMP");
+   info->bpp = stbi__get16le(s);
+   if (hsz != 12) {
+      int compress = stbi__get32le(s);
+      if (compress == 1 || compress == 2) return stbi__errpuc("BMP RLE", "BMP type not supported: RLE");
+      stbi__get32le(s); // discard sizeof
+      stbi__get32le(s); // discard hres
+      stbi__get32le(s); // discard vres
+      stbi__get32le(s); // discard colorsused
+      stbi__get32le(s); // discard max important
+      if (hsz == 40 || hsz == 56) {
+         if (hsz == 56) {
+            stbi__get32le(s);
+            stbi__get32le(s);
+            stbi__get32le(s);
+            stbi__get32le(s);
+         }
+         if (info->bpp == 16 || info->bpp == 32) {
+            if (compress == 0) {
+               if (info->bpp == 32) {
+                  info->mr = 0xffu << 16;
+                  info->mg = 0xffu <<  8;
+                  info->mb = 0xffu <<  0;
+                  info->ma = 0xffu << 24;
+                  info->all_a = 0; // if all_a is 0 at end, then we loaded alpha channel but it was all 0
+               } else {
+                  info->mr = 31u << 10;
+                  info->mg = 31u <<  5;
+                  info->mb = 31u <<  0;
+               }
+            } else if (compress == 3) {
+               info->mr = stbi__get32le(s);
+               info->mg = stbi__get32le(s);
+               info->mb = stbi__get32le(s);
+               // not documented, but generated by photoshop and handled by mspaint
+               if (info->mr == info->mg && info->mg == info->mb) {
+                  // ?!?!?
+                  return stbi__errpuc("bad BMP", "bad BMP");
+               }
+            } else
+               return stbi__errpuc("bad BMP", "bad BMP");
+         }
+      } else {
+         int i;
+         if (hsz != 108 && hsz != 124)
+            return stbi__errpuc("bad BMP", "bad BMP");
+         info->mr = stbi__get32le(s);
+         info->mg = stbi__get32le(s);
+         info->mb = stbi__get32le(s);
+         info->ma = stbi__get32le(s);
+         stbi__get32le(s); // discard color space
+         for (i=0; i < 12; ++i)
+            stbi__get32le(s); // discard color space parameters
+         if (hsz == 124) {
+            stbi__get32le(s); // discard rendering intent
+            stbi__get32le(s); // discard offset of profile data
+            stbi__get32le(s); // discard size of profile data
+            stbi__get32le(s); // discard reserved
+         }
+      }
+   }
+   return (void *) 1;
+}
+
+
+static void *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   stbi_uc *out;
+   unsigned int mr=0,mg=0,mb=0,ma=0, all_a;
+   stbi_uc pal[256][4];
+   int psize=0,i,j,width;
+   int flip_vertically, pad, target;
+   stbi__bmp_data info;
+   STBI_NOTUSED(ri);
+
+   info.all_a = 255;
+   if (stbi__bmp_parse_header(s, &info) == NULL)
+      return NULL; // error code already set
+
+   flip_vertically = ((int) s->img_y) > 0;
+   s->img_y = abs((int) s->img_y);
+
+   mr = info.mr;
+   mg = info.mg;
+   mb = info.mb;
+   ma = info.ma;
+   all_a = info.all_a;
+
+   if (info.hsz == 12) {
+      if (info.bpp < 24)
+         psize = (info.offset - 14 - 24) / 3;
+   } else {
+      if (info.bpp < 16)
+         psize = (info.offset - 14 - info.hsz) >> 2;
+   }
+
+   s->img_n = ma ? 4 : 3;
+   if (req_comp && req_comp >= 3) // we can directly decode 3 or 4
+      target = req_comp;
+   else
+      target = s->img_n; // if they want monochrome, we'll post-convert
+
+   // sanity-check size
+   if (!stbi__mad3sizes_valid(target, s->img_x, s->img_y, 0))
+      return stbi__errpuc("too large", "Corrupt BMP");
+
+   out = (stbi_uc *) stbi__malloc_mad3(target, s->img_x, s->img_y, 0);
+   if (!out) return stbi__errpuc("outofmem", "Out of memory");
+   if (info.bpp < 16) {
+      int z=0;
+      if (psize == 0 || psize > 256) { STBI_FREE(out); return stbi__errpuc("invalid", "Corrupt BMP"); }
+      for (i=0; i < psize; ++i) {
+         pal[i][2] = stbi__get8(s);
+         pal[i][1] = stbi__get8(s);
+         pal[i][0] = stbi__get8(s);
+         if (info.hsz != 12) stbi__get8(s);
+         pal[i][3] = 255;
+      }
+      stbi__skip(s, info.offset - 14 - info.hsz - psize * (info.hsz == 12 ? 3 : 4));
+      if (info.bpp == 1) width = (s->img_x + 7) >> 3;
+      else if (info.bpp == 4) width = (s->img_x + 1) >> 1;
+      else if (info.bpp == 8) width = s->img_x;
+      else { STBI_FREE(out); return stbi__errpuc("bad bpp", "Corrupt BMP"); }
+      pad = (-width)&3;
+      if (info.bpp == 1) {
+         for (j=0; j < (int) s->img_y; ++j) {
+            int bit_offset = 7, v = stbi__get8(s);
+            for (i=0; i < (int) s->img_x; ++i) {
+               int color = (v>>bit_offset)&0x1;
+               out[z++] = pal[color][0];
+               out[z++] = pal[color][1];
+               out[z++] = pal[color][2];
+               if (target == 4) out[z++] = 255;
+               if (i+1 == (int) s->img_x) break;
+               if((--bit_offset) < 0) {
+                  bit_offset = 7;
+                  v = stbi__get8(s);
+               }
+            }
+            stbi__skip(s, pad);
+         }
+      } else {
+         for (j=0; j < (int) s->img_y; ++j) {
+            for (i=0; i < (int) s->img_x; i += 2) {
+               int v=stbi__get8(s),v2=0;
+               if (info.bpp == 4) {
+                  v2 = v & 15;
+                  v >>= 4;
+               }
+               out[z++] = pal[v][0];
+               out[z++] = pal[v][1];
+               out[z++] = pal[v][2];
+               if (target == 4) out[z++] = 255;
+               if (i+1 == (int) s->img_x) break;
+               v = (info.bpp == 8) ? stbi__get8(s) : v2;
+               out[z++] = pal[v][0];
+               out[z++] = pal[v][1];
+               out[z++] = pal[v][2];
+               if (target == 4) out[z++] = 255;
+            }
+            stbi__skip(s, pad);
+         }
+      }
+   } else {
+      int rshift=0,gshift=0,bshift=0,ashift=0,rcount=0,gcount=0,bcount=0,acount=0;
+      int z = 0;
+      int easy=0;
+      stbi__skip(s, info.offset - 14 - info.hsz);
+      if (info.bpp == 24) width = 3 * s->img_x;
+      else if (info.bpp == 16) width = 2*s->img_x;
+      else /* bpp = 32 and pad = 0 */ width=0;
+      pad = (-width) & 3;
+      if (info.bpp == 24) {
+         easy = 1;
+      } else if (info.bpp == 32) {
+         if (mb == 0xff && mg == 0xff00 && mr == 0x00ff0000 && ma == 0xff000000)
+            easy = 2;
+      }
+      if (!easy) {
+         if (!mr || !mg || !mb) { STBI_FREE(out); return stbi__errpuc("bad masks", "Corrupt BMP"); }
+         // right shift amt to put high bit in position #7
+         rshift = stbi__high_bit(mr)-7; rcount = stbi__bitcount(mr);
+         gshift = stbi__high_bit(mg)-7; gcount = stbi__bitcount(mg);
+         bshift = stbi__high_bit(mb)-7; bcount = stbi__bitcount(mb);
+         ashift = stbi__high_bit(ma)-7; acount = stbi__bitcount(ma);
+      }
+      for (j=0; j < (int) s->img_y; ++j) {
+         if (easy) {
+            for (i=0; i < (int) s->img_x; ++i) {
+               unsigned char a;
+               out[z+2] = stbi__get8(s);
+               out[z+1] = stbi__get8(s);
+               out[z+0] = stbi__get8(s);
+               z += 3;
+               a = (easy == 2 ? stbi__get8(s) : 255);
+               all_a |= a;
+               if (target == 4) out[z++] = a;
+            }
+         } else {
+            int bpp = info.bpp;
+            for (i=0; i < (int) s->img_x; ++i) {
+               stbi__uint32 v = (bpp == 16 ? (stbi__uint32) stbi__get16le(s) : stbi__get32le(s));
+               unsigned int a;
+               out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mr, rshift, rcount));
+               out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mg, gshift, gcount));
+               out[z++] = STBI__BYTECAST(stbi__shiftsigned(v & mb, bshift, bcount));
+               a = (ma ? stbi__shiftsigned(v & ma, ashift, acount) : 255);
+               all_a |= a;
+               if (target == 4) out[z++] = STBI__BYTECAST(a);
+            }
+         }
+         stbi__skip(s, pad);
+      }
+   }
+
+   // if alpha channel is all 0s, replace with all 255s
+   if (target == 4 && all_a == 0)
+      for (i=4*s->img_x*s->img_y-1; i >= 0; i -= 4)
+         out[i] = 255;
+
+   if (flip_vertically) {
+      stbi_uc t;
+      for (j=0; j < (int) s->img_y>>1; ++j) {
+         stbi_uc *p1 = out +      j     *s->img_x*target;
+         stbi_uc *p2 = out + (s->img_y-1-j)*s->img_x*target;
+         for (i=0; i < (int) s->img_x*target; ++i) {
+            t = p1[i]; p1[i] = p2[i]; p2[i] = t;
+         }
+      }
+   }
+
+   if (req_comp && req_comp != target) {
+      out = stbi__convert_format(out, target, req_comp, s->img_x, s->img_y);
+      if (out == NULL) return out; // stbi__convert_format frees input on failure
+   }
+
+   *x = s->img_x;
+   *y = s->img_y;
+   if (comp) *comp = s->img_n;
+   return out;
+}
+#endif
+
+// Targa Truevision - TGA
+// by Jonathan Dummer
+#ifndef STBI_NO_TGA
+// returns STBI_rgb or whatever, 0 on error
+static int stbi__tga_get_comp(int bits_per_pixel, int is_grey, int* is_rgb16)
+{
+   // only RGB or RGBA (incl. 16bit) or grey allowed
+   if (is_rgb16) *is_rgb16 = 0;
+   switch(bits_per_pixel) {
+      case 8:  return STBI_grey;
+      case 16: if(is_grey) return STBI_grey_alpha;
+               // fallthrough
+      case 15: if(is_rgb16) *is_rgb16 = 1;
+               return STBI_rgb;
+      case 24: // fallthrough
+      case 32: return bits_per_pixel/8;
+      default: return 0;
+   }
+}
+
+static int stbi__tga_info(stbi__context *s, int *x, int *y, int *comp)
+{
+    int tga_w, tga_h, tga_comp, tga_image_type, tga_bits_per_pixel, tga_colormap_bpp;
+    int sz, tga_colormap_type;
+    stbi__get8(s);                   // discard Offset
+    tga_colormap_type = stbi__get8(s); // colormap type
+    if( tga_colormap_type > 1 ) {
+        stbi__rewind(s);
+        return 0;      // only RGB or indexed allowed
+    }
+    tga_image_type = stbi__get8(s); // image type
+    if ( tga_colormap_type == 1 ) { // colormapped (paletted) image
+        if (tga_image_type != 1 && tga_image_type != 9) {
+            stbi__rewind(s);
+            return 0;
+        }
+        stbi__skip(s,4);       // skip index of first colormap entry and number of entries
+        sz = stbi__get8(s);    //   check bits per palette color entry
+        if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) {
+            stbi__rewind(s);
+            return 0;
+        }
+        stbi__skip(s,4);       // skip image x and y origin
+        tga_colormap_bpp = sz;
+    } else { // "normal" image w/o colormap - only RGB or grey allowed, +/- RLE
+        if ( (tga_image_type != 2) && (tga_image_type != 3) && (tga_image_type != 10) && (tga_image_type != 11) ) {
+            stbi__rewind(s);
+            return 0; // only RGB or grey allowed, +/- RLE
+        }
+        stbi__skip(s,9); // skip colormap specification and image x/y origin
+        tga_colormap_bpp = 0;
+    }
+    tga_w = stbi__get16le(s);
+    if( tga_w < 1 ) {
+        stbi__rewind(s);
+        return 0;   // test width
+    }
+    tga_h = stbi__get16le(s);
+    if( tga_h < 1 ) {
+        stbi__rewind(s);
+        return 0;   // test height
+    }
+    tga_bits_per_pixel = stbi__get8(s); // bits per pixel
+    stbi__get8(s); // ignore alpha bits
+    if (tga_colormap_bpp != 0) {
+        if((tga_bits_per_pixel != 8) && (tga_bits_per_pixel != 16)) {
+            // when using a colormap, tga_bits_per_pixel is the size of the indexes
+            // I don't think anything but 8 or 16bit indexes makes sense
+            stbi__rewind(s);
+            return 0;
+        }
+        tga_comp = stbi__tga_get_comp(tga_colormap_bpp, 0, NULL);
+    } else {
+        tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3) || (tga_image_type == 11), NULL);
+    }
+    if(!tga_comp) {
+      stbi__rewind(s);
+      return 0;
+    }
+    if (x) *x = tga_w;
+    if (y) *y = tga_h;
+    if (comp) *comp = tga_comp;
+    return 1;                   // seems to have passed everything
+}
+
+static int stbi__tga_test(stbi__context *s)
+{
+   int res = 0;
+   int sz, tga_color_type;
+   stbi__get8(s);      //   discard Offset
+   tga_color_type = stbi__get8(s);   //   color type
+   if ( tga_color_type > 1 ) goto errorEnd;   //   only RGB or indexed allowed
+   sz = stbi__get8(s);   //   image type
+   if ( tga_color_type == 1 ) { // colormapped (paletted) image
+      if (sz != 1 && sz != 9) goto errorEnd; // colortype 1 demands image type 1 or 9
+      stbi__skip(s,4);       // skip index of first colormap entry and number of entries
+      sz = stbi__get8(s);    //   check bits per palette color entry
+      if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd;
+      stbi__skip(s,4);       // skip image x and y origin
+   } else { // "normal" image w/o colormap
+      if ( (sz != 2) && (sz != 3) && (sz != 10) && (sz != 11) ) goto errorEnd; // only RGB or grey allowed, +/- RLE
+      stbi__skip(s,9); // skip colormap specification and image x/y origin
+   }
+   if ( stbi__get16le(s) < 1 ) goto errorEnd;      //   test width
+   if ( stbi__get16le(s) < 1 ) goto errorEnd;      //   test height
+   sz = stbi__get8(s);   //   bits per pixel
+   if ( (tga_color_type == 1) && (sz != 8) && (sz != 16) ) goto errorEnd; // for colormapped images, bpp is size of an index
+   if ( (sz != 8) && (sz != 15) && (sz != 16) && (sz != 24) && (sz != 32) ) goto errorEnd;
+
+   res = 1; // if we got this far, everything's good and we can return 1 instead of 0
+
+errorEnd:
+   stbi__rewind(s);
+   return res;
+}
+
+// read 16bit value and convert to 24bit RGB
+static void stbi__tga_read_rgb16(stbi__context *s, stbi_uc* out)
+{
+   stbi__uint16 px = (stbi__uint16)stbi__get16le(s);
+   stbi__uint16 fiveBitMask = 31;
+   // we have 3 channels with 5bits each
+   int r = (px >> 10) & fiveBitMask;
+   int g = (px >> 5) & fiveBitMask;
+   int b = px & fiveBitMask;
+   // Note that this saves the data in RGB(A) order, so it doesn't need to be swapped later
+   out[0] = (stbi_uc)((r * 255)/31);
+   out[1] = (stbi_uc)((g * 255)/31);
+   out[2] = (stbi_uc)((b * 255)/31);
+
+   // some people claim that the most significant bit might be used for alpha
+   // (possibly if an alpha-bit is set in the "image descriptor byte")
+   // but that only made 16bit test images completely translucent..
+   // so let's treat all 15 and 16bit TGAs as RGB with no alpha.
+}
+
+static void *stbi__tga_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   //   read in the TGA header stuff
+   int tga_offset = stbi__get8(s);
+   int tga_indexed = stbi__get8(s);
+   int tga_image_type = stbi__get8(s);
+   int tga_is_RLE = 0;
+   int tga_palette_start = stbi__get16le(s);
+   int tga_palette_len = stbi__get16le(s);
+   int tga_palette_bits = stbi__get8(s);
+   int tga_x_origin = stbi__get16le(s);
+   int tga_y_origin = stbi__get16le(s);
+   int tga_width = stbi__get16le(s);
+   int tga_height = stbi__get16le(s);
+   int tga_bits_per_pixel = stbi__get8(s);
+   int tga_comp, tga_rgb16=0;
+   int tga_inverted = stbi__get8(s);
+   // int tga_alpha_bits = tga_inverted & 15; // the 4 lowest bits - unused (useless?)
+   //   image data
+   unsigned char *tga_data;
+   unsigned char *tga_palette = NULL;
+   int i, j;
+   unsigned char raw_data[4] = {0};
+   int RLE_count = 0;
+   int RLE_repeating = 0;
+   int read_next_pixel = 1;
+   STBI_NOTUSED(ri);
+
+   //   do a tiny bit of precessing
+   if ( tga_image_type >= 8 )
+   {
+      tga_image_type -= 8;
+      tga_is_RLE = 1;
+   }
+   tga_inverted = 1 - ((tga_inverted >> 5) & 1);
+
+   //   If I'm paletted, then I'll use the number of bits from the palette
+   if ( tga_indexed ) tga_comp = stbi__tga_get_comp(tga_palette_bits, 0, &tga_rgb16);
+   else tga_comp = stbi__tga_get_comp(tga_bits_per_pixel, (tga_image_type == 3), &tga_rgb16);
+
+   if(!tga_comp) // shouldn't really happen, stbi__tga_test() should have ensured basic consistency
+      return stbi__errpuc("bad format", "Can't find out TGA pixelformat");
+
+   //   tga info
+   *x = tga_width;
+   *y = tga_height;
+   if (comp) *comp = tga_comp;
+
+   if (!stbi__mad3sizes_valid(tga_width, tga_height, tga_comp, 0))
+      return stbi__errpuc("too large", "Corrupt TGA");
+
+   tga_data = (unsigned char*)stbi__malloc_mad3(tga_width, tga_height, tga_comp, 0);
+   if (!tga_data) return stbi__errpuc("outofmem", "Out of memory");
+
+   // skip to the data's starting position (offset usually = 0)
+   stbi__skip(s, tga_offset );
+
+   if ( !tga_indexed && !tga_is_RLE && !tga_rgb16 ) {
+      for (i=0; i < tga_height; ++i) {
+         int row = tga_inverted ? tga_height -i - 1 : i;
+         stbi_uc *tga_row = tga_data + row*tga_width*tga_comp;
+         stbi__getn(s, tga_row, tga_width * tga_comp);
+      }
+   } else  {
+      //   do I need to load a palette?
+      if ( tga_indexed)
+      {
+         //   any data to skip? (offset usually = 0)
+         stbi__skip(s, tga_palette_start );
+         //   load the palette
+         tga_palette = (unsigned char*)stbi__malloc_mad2(tga_palette_len, tga_comp, 0);
+         if (!tga_palette) {
+            STBI_FREE(tga_data);
+            return stbi__errpuc("outofmem", "Out of memory");
+         }
+         if (tga_rgb16) {
+            stbi_uc *pal_entry = tga_palette;
+            STBI_ASSERT(tga_comp == STBI_rgb);
+            for (i=0; i < tga_palette_len; ++i) {
+               stbi__tga_read_rgb16(s, pal_entry);
+               pal_entry += tga_comp;
+            }
+         } else if (!stbi__getn(s, tga_palette, tga_palette_len * tga_comp)) {
+               STBI_FREE(tga_data);
+               STBI_FREE(tga_palette);
+               return stbi__errpuc("bad palette", "Corrupt TGA");
+         }
+      }
+      //   load the data
+      for (i=0; i < tga_width * tga_height; ++i)
+      {
+         //   if I'm in RLE mode, do I need to get a RLE stbi__pngchunk?
+         if ( tga_is_RLE )
+         {
+            if ( RLE_count == 0 )
+            {
+               //   yep, get the next byte as a RLE command
+               int RLE_cmd = stbi__get8(s);
+               RLE_count = 1 + (RLE_cmd & 127);
+               RLE_repeating = RLE_cmd >> 7;
+               read_next_pixel = 1;
+            } else if ( !RLE_repeating )
+            {
+               read_next_pixel = 1;
+            }
+         } else
+         {
+            read_next_pixel = 1;
+         }
+         //   OK, if I need to read a pixel, do it now
+         if ( read_next_pixel )
+         {
+            //   load however much data we did have
+            if ( tga_indexed )
+            {
+               // read in index, then perform the lookup
+               int pal_idx = (tga_bits_per_pixel == 8) ? stbi__get8(s) : stbi__get16le(s);
+               if ( pal_idx >= tga_palette_len ) {
+                  // invalid index
+                  pal_idx = 0;
+               }
+               pal_idx *= tga_comp;
+               for (j = 0; j < tga_comp; ++j) {
+                  raw_data[j] = tga_palette[pal_idx+j];
+               }
+            } else if(tga_rgb16) {
+               STBI_ASSERT(tga_comp == STBI_rgb);
+               stbi__tga_read_rgb16(s, raw_data);
+            } else {
+               //   read in the data raw
+               for (j = 0; j < tga_comp; ++j) {
+                  raw_data[j] = stbi__get8(s);
+               }
+            }
+            //   clear the reading flag for the next pixel
+            read_next_pixel = 0;
+         } // end of reading a pixel
+
+         // copy data
+         for (j = 0; j < tga_comp; ++j)
+           tga_data[i*tga_comp+j] = raw_data[j];
+
+         //   in case we're in RLE mode, keep counting down
+         --RLE_count;
+      }
+      //   do I need to invert the image?
+      if ( tga_inverted )
+      {
+         for (j = 0; j*2 < tga_height; ++j)
+         {
+            int index1 = j * tga_width * tga_comp;
+            int index2 = (tga_height - 1 - j) * tga_width * tga_comp;
+            for (i = tga_width * tga_comp; i > 0; --i)
+            {
+               unsigned char temp = tga_data[index1];
+               tga_data[index1] = tga_data[index2];
+               tga_data[index2] = temp;
+               ++index1;
+               ++index2;
+            }
+         }
+      }
+      //   clear my palette, if I had one
+      if ( tga_palette != NULL )
+      {
+         STBI_FREE( tga_palette );
+      }
+   }
+
+   // swap RGB - if the source data was RGB16, it already is in the right order
+   if (tga_comp >= 3 && !tga_rgb16)
+   {
+      unsigned char* tga_pixel = tga_data;
+      for (i=0; i < tga_width * tga_height; ++i)
+      {
+         unsigned char temp = tga_pixel[0];
+         tga_pixel[0] = tga_pixel[2];
+         tga_pixel[2] = temp;
+         tga_pixel += tga_comp;
+      }
+   }
+
+   // convert to target component count
+   if (req_comp && req_comp != tga_comp)
+      tga_data = stbi__convert_format(tga_data, tga_comp, req_comp, tga_width, tga_height);
+
+   //   the things I do to get rid of an error message, and yet keep
+   //   Microsoft's C compilers happy... [8^(
+   tga_palette_start = tga_palette_len = tga_palette_bits =
+         tga_x_origin = tga_y_origin = 0;
+   //   OK, done
+   return tga_data;
+}
+#endif
+
+// *************************************************************************************************
+// Photoshop PSD loader -- PD by Thatcher Ulrich, integration by Nicolas Schulz, tweaked by STB
+
+#ifndef STBI_NO_PSD
+static int stbi__psd_test(stbi__context *s)
+{
+   int r = (stbi__get32be(s) == 0x38425053);
+   stbi__rewind(s);
+   return r;
+}
+
+static int stbi__psd_decode_rle(stbi__context *s, stbi_uc *p, int pixelCount)
+{
+   int count, nleft, len;
+
+   count = 0;
+   while ((nleft = pixelCount - count) > 0) {
+      len = stbi__get8(s);
+      if (len == 128) {
+         // No-op.
+      } else if (len < 128) {
+         // Copy next len+1 bytes literally.
+         len++;
+         if (len > nleft) return 0; // corrupt data
+         count += len;
+         while (len) {
+            *p = stbi__get8(s);
+            p += 4;
+            len--;
+         }
+      } else if (len > 128) {
+         stbi_uc   val;
+         // Next -len+1 bytes in the dest are replicated from next source byte.
+         // (Interpret len as a negative 8-bit int.)
+         len = 257 - len;
+         if (len > nleft) return 0; // corrupt data
+         val = stbi__get8(s);
+         count += len;
+         while (len) {
+            *p = val;
+            p += 4;
+            len--;
+         }
+      }
+   }
+
+   return 1;
+}
+
+static void *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri, int bpc)
+{
+   int pixelCount;
+   int channelCount, compression;
+   int channel, i;
+   int bitdepth;
+   int w,h;
+   stbi_uc *out;
+   STBI_NOTUSED(ri);
+
+   // Check identifier
+   if (stbi__get32be(s) != 0x38425053)   // "8BPS"
+      return stbi__errpuc("not PSD", "Corrupt PSD image");
+
+   // Check file type version.
+   if (stbi__get16be(s) != 1)
+      return stbi__errpuc("wrong version", "Unsupported version of PSD image");
+
+   // Skip 6 reserved bytes.
+   stbi__skip(s, 6 );
+
+   // Read the number of channels (R, G, B, A, etc).
+   channelCount = stbi__get16be(s);
+   if (channelCount < 0 || channelCount > 16)
+      return stbi__errpuc("wrong channel count", "Unsupported number of channels in PSD image");
+
+   // Read the rows and columns of the image.
+   h = stbi__get32be(s);
+   w = stbi__get32be(s);
+
+   // Make sure the depth is 8 bits.
+   bitdepth = stbi__get16be(s);
+   if (bitdepth != 8 && bitdepth != 16)
+      return stbi__errpuc("unsupported bit depth", "PSD bit depth is not 8 or 16 bit");
+
+   // Make sure the color mode is RGB.
+   // Valid options are:
+   //   0: Bitmap
+   //   1: Grayscale
+   //   2: Indexed color
+   //   3: RGB color
+   //   4: CMYK color
+   //   7: Multichannel
+   //   8: Duotone
+   //   9: Lab color
+   if (stbi__get16be(s) != 3)
+      return stbi__errpuc("wrong color format", "PSD is not in RGB color format");
+
+   // Skip the Mode Data.  (It's the palette for indexed color; other info for other modes.)
+   stbi__skip(s,stbi__get32be(s) );
+
+   // Skip the image resources.  (resolution, pen tool paths, etc)
+   stbi__skip(s, stbi__get32be(s) );
+
+   // Skip the reserved data.
+   stbi__skip(s, stbi__get32be(s) );
+
+   // Find out if the data is compressed.
+   // Known values:
+   //   0: no compression
+   //   1: RLE compressed
+   compression = stbi__get16be(s);
+   if (compression > 1)
+      return stbi__errpuc("bad compression", "PSD has an unknown compression format");
+
+   // Check size
+   if (!stbi__mad3sizes_valid(4, w, h, 0))
+      return stbi__errpuc("too large", "Corrupt PSD");
+
+   // Create the destination image.
+
+   if (!compression && bitdepth == 16 && bpc == 16) {
+      out = (stbi_uc *) stbi__malloc_mad3(8, w, h, 0);
+      ri->bits_per_channel = 16;
+   } else
+      out = (stbi_uc *) stbi__malloc(4 * w*h);
+
+   if (!out) return stbi__errpuc("outofmem", "Out of memory");
+   pixelCount = w*h;
+
+   // Initialize the data to zero.
+   //memset( out, 0, pixelCount * 4 );
+
+   // Finally, the image data.
+   if (compression) {
+      // RLE as used by .PSD and .TIFF
+      // Loop until you get the number of unpacked bytes you are expecting:
+      //     Read the next source byte into n.
+      //     If n is between 0 and 127 inclusive, copy the next n+1 bytes literally.
+      //     Else if n is between -127 and -1 inclusive, copy the next byte -n+1 times.
+      //     Else if n is 128, noop.
+      // Endloop
+
+      // The RLE-compressed data is preceded by a 2-byte data count for each row in the data,
+      // which we're going to just skip.
+      stbi__skip(s, h * channelCount * 2 );
+
+      // Read the RLE data by channel.
+      for (channel = 0; channel < 4; channel++) {
+         stbi_uc *p;
+
+         p = out+channel;
+         if (channel >= channelCount) {
+            // Fill this channel with default data.
+            for (i = 0; i < pixelCount; i++, p += 4)
+               *p = (channel == 3 ? 255 : 0);
+         } else {
+            // Read the RLE data.
+            if (!stbi__psd_decode_rle(s, p, pixelCount)) {
+               STBI_FREE(out);
+               return stbi__errpuc("corrupt", "bad RLE data");
+            }
+         }
+      }
+
+   } else {
+      // We're at the raw image data.  It's each channel in order (Red, Green, Blue, Alpha, ...)
+      // where each channel consists of an 8-bit (or 16-bit) value for each pixel in the image.
+
+      // Read the data by channel.
+      for (channel = 0; channel < 4; channel++) {
+         if (channel >= channelCount) {
+            // Fill this channel with default data.
+            if (bitdepth == 16 && bpc == 16) {
+               stbi__uint16 *q = ((stbi__uint16 *) out) + channel;
+               stbi__uint16 val = channel == 3 ? 65535 : 0;
+               for (i = 0; i < pixelCount; i++, q += 4)
+                  *q = val;
+            } else {
+               stbi_uc *p = out+channel;
+               stbi_uc val = channel == 3 ? 255 : 0;
+               for (i = 0; i < pixelCount; i++, p += 4)
+                  *p = val;
+            }
+         } else {
+            if (ri->bits_per_channel == 16) {    // output bpc
+               stbi__uint16 *q = ((stbi__uint16 *) out) + channel;
+               for (i = 0; i < pixelCount; i++, q += 4)
+                  *q = (stbi__uint16) stbi__get16be(s);
+            } else {
+               stbi_uc *p = out+channel;
+               if (bitdepth == 16) {  // input bpc
+                  for (i = 0; i < pixelCount; i++, p += 4)
+                     *p = (stbi_uc) (stbi__get16be(s) >> 8);
+               } else {
+                  for (i = 0; i < pixelCount; i++, p += 4)
+                     *p = stbi__get8(s);
+               }
+            }
+         }
+      }
+   }
+
+   // remove weird white matte from PSD
+   if (channelCount >= 4) {
+      if (ri->bits_per_channel == 16) {
+         for (i=0; i < w*h; ++i) {
+            stbi__uint16 *pixel = (stbi__uint16 *) out + 4*i;
+            if (pixel[3] != 0 && pixel[3] != 65535) {
+               float a = pixel[3] / 65535.0f;
+               float ra = 1.0f / a;
+               float inv_a = 65535.0f * (1 - ra);
+               pixel[0] = (stbi__uint16) (pixel[0]*ra + inv_a);
+               pixel[1] = (stbi__uint16) (pixel[1]*ra + inv_a);
+               pixel[2] = (stbi__uint16) (pixel[2]*ra + inv_a);
+            }
+         }
+      } else {
+         for (i=0; i < w*h; ++i) {
+            unsigned char *pixel = out + 4*i;
+            if (pixel[3] != 0 && pixel[3] != 255) {
+               float a = pixel[3] / 255.0f;
+               float ra = 1.0f / a;
+               float inv_a = 255.0f * (1 - ra);
+               pixel[0] = (unsigned char) (pixel[0]*ra + inv_a);
+               pixel[1] = (unsigned char) (pixel[1]*ra + inv_a);
+               pixel[2] = (unsigned char) (pixel[2]*ra + inv_a);
+            }
+         }
+      }
+   }
+
+   // convert to desired output format
+   if (req_comp && req_comp != 4) {
+      if (ri->bits_per_channel == 16)
+         out = (stbi_uc *) stbi__convert_format16((stbi__uint16 *) out, 4, req_comp, w, h);
+      else
+         out = stbi__convert_format(out, 4, req_comp, w, h);
+      if (out == NULL) return out; // stbi__convert_format frees input on failure
+   }
+
+   if (comp) *comp = 4;
+   *y = h;
+   *x = w;
+
+   return out;
+}
+#endif
+
+// *************************************************************************************************
+// Softimage PIC loader
+// by Tom Seddon
+//
+// See http://softimage.wiki.softimage.com/index.php/INFO:_PIC_file_format
+// See http://ozviz.wasp.uwa.edu.au/~pbourke/dataformats/softimagepic/
+
+#ifndef STBI_NO_PIC
+static int stbi__pic_is4(stbi__context *s,const char *str)
+{
+   int i;
+   for (i=0; i<4; ++i)
+      if (stbi__get8(s) != (stbi_uc)str[i])
+         return 0;
+
+   return 1;
+}
+
+static int stbi__pic_test_core(stbi__context *s)
+{
+   int i;
+
+   if (!stbi__pic_is4(s,"\x53\x80\xF6\x34"))
+      return 0;
+
+   for(i=0;i<84;++i)
+      stbi__get8(s);
+
+   if (!stbi__pic_is4(s,"PICT"))
+      return 0;
+
+   return 1;
+}
+
+typedef struct
+{
+   stbi_uc size,type,channel;
+} stbi__pic_packet;
+
+static stbi_uc *stbi__readval(stbi__context *s, int channel, stbi_uc *dest)
+{
+   int mask=0x80, i;
+
+   for (i=0; i<4; ++i, mask>>=1) {
+      if (channel & mask) {
+         if (stbi__at_eof(s)) return stbi__errpuc("bad file","PIC file too short");
+         dest[i]=stbi__get8(s);
+      }
+   }
+
+   return dest;
+}
+
+static void stbi__copyval(int channel,stbi_uc *dest,const stbi_uc *src)
+{
+   int mask=0x80,i;
+
+   for (i=0;i<4; ++i, mask>>=1)
+      if (channel&mask)
+         dest[i]=src[i];
+}
+
+static stbi_uc *stbi__pic_load_core(stbi__context *s,int width,int height,int *comp, stbi_uc *result)
+{
+   int act_comp=0,num_packets=0,y,chained;
+   stbi__pic_packet packets[10];
+
+   // this will (should...) cater for even some bizarre stuff like having data
+    // for the same channel in multiple packets.
+   do {
+      stbi__pic_packet *packet;
+
+      if (num_packets==sizeof(packets)/sizeof(packets[0]))
+         return stbi__errpuc("bad format","too many packets");
+
+      packet = &packets[num_packets++];
+
+      chained = stbi__get8(s);
+      packet->size    = stbi__get8(s);
+      packet->type    = stbi__get8(s);
+      packet->channel = stbi__get8(s);
+
+      act_comp |= packet->channel;
+
+      if (stbi__at_eof(s))          return stbi__errpuc("bad file","file too short (reading packets)");
+      if (packet->size != 8)  return stbi__errpuc("bad format","packet isn't 8bpp");
+   } while (chained);
+
+   *comp = (act_comp & 0x10 ? 4 : 3); // has alpha channel?
+
+   for(y=0; y<height; ++y) {
+      int packet_idx;
+
+      for(packet_idx=0; packet_idx < num_packets; ++packet_idx) {
+         stbi__pic_packet *packet = &packets[packet_idx];
+         stbi_uc *dest = result+y*width*4;
+
+         switch (packet->type) {
+            default:
+               return stbi__errpuc("bad format","packet has bad compression type");
+
+            case 0: {//uncompressed
+               int x;
+
+               for(x=0;x<width;++x, dest+=4)
+                  if (!stbi__readval(s,packet->channel,dest))
+                     return 0;
+               break;
+            }
+
+            case 1://Pure RLE
+               {
+                  int left=width, i;
+
+                  while (left>0) {
+                     stbi_uc count,value[4];
+
+                     count=stbi__get8(s);
+                     if (stbi__at_eof(s))   return stbi__errpuc("bad file","file too short (pure read count)");
+
+                     if (count > left)
+                        count = (stbi_uc) left;
+
+                     if (!stbi__readval(s,packet->channel,value))  return 0;
+
+                     for(i=0; i<count; ++i,dest+=4)
+                        stbi__copyval(packet->channel,dest,value);
+                     left -= count;
+                  }
+               }
+               break;
+
+            case 2: {//Mixed RLE
+               int left=width;
+               while (left>0) {
+                  int count = stbi__get8(s), i;
+                  if (stbi__at_eof(s))  return stbi__errpuc("bad file","file too short (mixed read count)");
+
+                  if (count >= 128) { // Repeated
+                     stbi_uc value[4];
+
+                     if (count==128)
+                        count = stbi__get16be(s);
+                     else
+                        count -= 127;
+                     if (count > left)
+                        return stbi__errpuc("bad file","scanline overrun");
+
+                     if (!stbi__readval(s,packet->channel,value))
+                        return 0;
+
+                     for(i=0;i<count;++i, dest += 4)
+                        stbi__copyval(packet->channel,dest,value);
+                  } else { // Raw
+                     ++count;
+                     if (count>left) return stbi__errpuc("bad file","scanline overrun");
+
+                     for(i=0;i<count;++i, dest+=4)
+                        if (!stbi__readval(s,packet->channel,dest))
+                           return 0;
+                  }
+                  left-=count;
+               }
+               break;
+            }
+         }
+      }
+   }
+
+   return result;
+}
+
+static void *stbi__pic_load(stbi__context *s,int *px,int *py,int *comp,int req_comp, stbi__result_info *ri)
+{
+   stbi_uc *result;
+   int i, x,y, internal_comp;
+   STBI_NOTUSED(ri);
+
+   if (!comp) comp = &internal_comp;
+
+   for (i=0; i<92; ++i)
+      stbi__get8(s);
+
+   x = stbi__get16be(s);
+   y = stbi__get16be(s);
+   if (stbi__at_eof(s))  return stbi__errpuc("bad file","file too short (pic header)");
+   if (!stbi__mad3sizes_valid(x, y, 4, 0)) return stbi__errpuc("too large", "PIC image too large to decode");
+
+   stbi__get32be(s); //skip `ratio'
+   stbi__get16be(s); //skip `fields'
+   stbi__get16be(s); //skip `pad'
+
+   // intermediate buffer is RGBA
+   result = (stbi_uc *) stbi__malloc_mad3(x, y, 4, 0);
+   memset(result, 0xff, x*y*4);
+
+   if (!stbi__pic_load_core(s,x,y,comp, result)) {
+      STBI_FREE(result);
+      result=0;
+   }
+   *px = x;
+   *py = y;
+   if (req_comp == 0) req_comp = *comp;
+   result=stbi__convert_format(result,4,req_comp,x,y);
+
+   return result;
+}
+
+static int stbi__pic_test(stbi__context *s)
+{
+   int r = stbi__pic_test_core(s);
+   stbi__rewind(s);
+   return r;
+}
+#endif
+
+// *************************************************************************************************
+// GIF loader -- public domain by Jean-Marc Lienher -- simplified/shrunk by stb
+
+#ifndef STBI_NO_GIF
+typedef struct
+{
+   stbi__int16 prefix;
+   stbi_uc first;
+   stbi_uc suffix;
+} stbi__gif_lzw;
+
+typedef struct
+{
+   int w,h;
+   stbi_uc *out;                 // output buffer (always 4 components)
+   stbi_uc *background;          // The current "background" as far as a gif is concerned
+   stbi_uc *history; 
+   int flags, bgindex, ratio, transparent, eflags;
+   stbi_uc  pal[256][4];
+   stbi_uc lpal[256][4];
+   stbi__gif_lzw codes[8192];
+   stbi_uc *color_table;
+   int parse, step;
+   int lflags;
+   int start_x, start_y;
+   int max_x, max_y;
+   int cur_x, cur_y;
+   int line_size;
+   int delay;
+} stbi__gif;
+
+static int stbi__gif_test_raw(stbi__context *s)
+{
+   int sz;
+   if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8') return 0;
+   sz = stbi__get8(s);
+   if (sz != '9' && sz != '7') return 0;
+   if (stbi__get8(s) != 'a') return 0;
+   return 1;
+}
+
+static int stbi__gif_test(stbi__context *s)
+{
+   int r = stbi__gif_test_raw(s);
+   stbi__rewind(s);
+   return r;
+}
+
+static void stbi__gif_parse_colortable(stbi__context *s, stbi_uc pal[256][4], int num_entries, int transp)
+{
+   int i;
+   for (i=0; i < num_entries; ++i) {
+      pal[i][2] = stbi__get8(s);
+      pal[i][1] = stbi__get8(s);
+      pal[i][0] = stbi__get8(s);
+      pal[i][3] = transp == i ? 0 : 255;
+   }
+}
+
+static int stbi__gif_header(stbi__context *s, stbi__gif *g, int *comp, int is_info)
+{
+   stbi_uc version;
+   if (stbi__get8(s) != 'G' || stbi__get8(s) != 'I' || stbi__get8(s) != 'F' || stbi__get8(s) != '8')
+      return stbi__err("not GIF", "Corrupt GIF");
+
+   version = stbi__get8(s);
+   if (version != '7' && version != '9')    return stbi__err("not GIF", "Corrupt GIF");
+   if (stbi__get8(s) != 'a')                return stbi__err("not GIF", "Corrupt GIF");
+
+   stbi__g_failure_reason = "";
+   g->w = stbi__get16le(s);
+   g->h = stbi__get16le(s);
+   g->flags = stbi__get8(s);
+   g->bgindex = stbi__get8(s);
+   g->ratio = stbi__get8(s);
+   g->transparent = -1;
+
+   if (comp != 0) *comp = 4;  // can't actually tell whether it's 3 or 4 until we parse the comments
+
+   if (is_info) return 1;
+
+   if (g->flags & 0x80)
+      stbi__gif_parse_colortable(s,g->pal, 2 << (g->flags & 7), -1);
+
+   return 1;
+}
+
+static int stbi__gif_info_raw(stbi__context *s, int *x, int *y, int *comp)
+{
+   stbi__gif* g = (stbi__gif*) stbi__malloc(sizeof(stbi__gif));
+   if (!stbi__gif_header(s, g, comp, 1)) {
+      STBI_FREE(g);
+      stbi__rewind( s );
+      return 0;
+   }
+   if (x) *x = g->w;
+   if (y) *y = g->h;
+   STBI_FREE(g);
+   return 1;
+}
+
+static void stbi__out_gif_code(stbi__gif *g, stbi__uint16 code)
+{
+   stbi_uc *p, *c;
+   int idx; 
+
+   // recurse to decode the prefixes, since the linked-list is backwards,
+   // and working backwards through an interleaved image would be nasty
+   if (g->codes[code].prefix >= 0)
+      stbi__out_gif_code(g, g->codes[code].prefix);
+
+   if (g->cur_y >= g->max_y) return;
+
+   idx = g->cur_x + g->cur_y; 
+   p = &g->out[idx];
+   g->history[idx / 4] = 1;  
+
+   c = &g->color_table[g->codes[code].suffix * 4];
+   if (c[3] > 128) { // don't render transparent pixels; 
+      p[0] = c[2];
+      p[1] = c[1];
+      p[2] = c[0];
+      p[3] = c[3];
+   }
+   g->cur_x += 4;
+
+   if (g->cur_x >= g->max_x) {
+      g->cur_x = g->start_x;
+      g->cur_y += g->step;
+
+      while (g->cur_y >= g->max_y && g->parse > 0) {
+         g->step = (1 << g->parse) * g->line_size;
+         g->cur_y = g->start_y + (g->step >> 1);
+         --g->parse;
+      }
+   }
+}
+
+static stbi_uc *stbi__process_gif_raster(stbi__context *s, stbi__gif *g)
+{
+   stbi_uc lzw_cs;
+   stbi__int32 len, init_code;
+   stbi__uint32 first;
+   stbi__int32 codesize, codemask, avail, oldcode, bits, valid_bits, clear;
+   stbi__gif_lzw *p;
+
+   lzw_cs = stbi__get8(s);
+   if (lzw_cs > 12) return NULL;
+   clear = 1 << lzw_cs;
+   first = 1;
+   codesize = lzw_cs + 1;
+   codemask = (1 << codesize) - 1;
+   bits = 0;
+   valid_bits = 0;
+   for (init_code = 0; init_code < clear; init_code++) {
+      g->codes[init_code].prefix = -1;
+      g->codes[init_code].first = (stbi_uc) init_code;
+      g->codes[init_code].suffix = (stbi_uc) init_code;
+   }
+
+   // support no starting clear code
+   avail = clear+2;
+   oldcode = -1;
+
+   len = 0;
+   for(;;) {
+      if (valid_bits < codesize) {
+         if (len == 0) {
+            len = stbi__get8(s); // start new block
+            if (len == 0)
+               return g->out;
+         }
+         --len;
+         bits |= (stbi__int32) stbi__get8(s) << valid_bits;
+         valid_bits += 8;
+      } else {
+         stbi__int32 code = bits & codemask;
+         bits >>= codesize;
+         valid_bits -= codesize;
+         // @OPTIMIZE: is there some way we can accelerate the non-clear path?
+         if (code == clear) {  // clear code
+            codesize = lzw_cs + 1;
+            codemask = (1 << codesize) - 1;
+            avail = clear + 2;
+            oldcode = -1;
+            first = 0;
+         } else if (code == clear + 1) { // end of stream code
+            stbi__skip(s, len);
+            while ((len = stbi__get8(s)) > 0)
+               stbi__skip(s,len);
+            return g->out;
+         } else if (code <= avail) {
+            if (first) {
+               return stbi__errpuc("no clear code", "Corrupt GIF");
+            }
+
+            if (oldcode >= 0) {
+               p = &g->codes[avail++];
+               if (avail > 8192) {
+                  return stbi__errpuc("too many codes", "Corrupt GIF");
+               }
+
+               p->prefix = (stbi__int16) oldcode;
+               p->first = g->codes[oldcode].first;
+               p->suffix = (code == avail) ? p->first : g->codes[code].first;
+            } else if (code == avail)
+               return stbi__errpuc("illegal code in raster", "Corrupt GIF");
+
+            stbi__out_gif_code(g, (stbi__uint16) code);
+
+            if ((avail & codemask) == 0 && avail <= 0x0FFF) {
+               codesize++;
+               codemask = (1 << codesize) - 1;
+            }
+
+            oldcode = code;
+         } else {
+            return stbi__errpuc("illegal code in raster", "Corrupt GIF");
+         }
+      }
+   }
+}
+
+// this function is designed to support animated gifs, although stb_image doesn't support it
+// two back is the image from two frames ago, used for a very specific disposal format
+static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, int req_comp, stbi_uc *two_back)
+{
+   int dispose; 
+   int first_frame; 
+   int pi; 
+   int pcount; 
+   STBI_NOTUSED(req_comp);
+
+   // on first frame, any non-written pixels get the background colour (non-transparent)
+   first_frame = 0; 
+   if (g->out == 0) {
+      if (!stbi__gif_header(s, g, comp,0))     return 0; // stbi__g_failure_reason set by stbi__gif_header
+      g->out = (stbi_uc *) stbi__malloc(4 * g->w * g->h);
+      g->background = (stbi_uc *) stbi__malloc(4 * g->w * g->h); 
+      g->history = (stbi_uc *) stbi__malloc(g->w * g->h); 
+      if (g->out == 0)                      return stbi__errpuc("outofmem", "Out of memory");
+
+      // image is treated as "transparent" at the start - ie, nothing overwrites the current background; 
+      // background colour is only used for pixels that are not rendered first frame, after that "background"
+      // color refers to the color that was there the previous frame. 
+      memset( g->out, 0x00, 4 * g->w * g->h ); 
+      memset( g->background, 0x00, 4 * g->w * g->h ); // state of the background (starts transparent)
+      memset( g->history, 0x00, g->w * g->h );        // pixels that were affected previous frame
+      first_frame = 1; 
+   } else {
+      // second frame - how do we dispoase of the previous one?
+      dispose = (g->eflags & 0x1C) >> 2; 
+      pcount = g->w * g->h; 
+
+      if ((dispose == 3) && (two_back == 0)) {
+         dispose = 2; // if I don't have an image to revert back to, default to the old background
+      }
+
+      if (dispose == 3) { // use previous graphic
+         for (pi = 0; pi < pcount; ++pi) {
+            if (g->history[pi]) {
+               memcpy( &g->out[pi * 4], &two_back[pi * 4], 4 ); 
+            }
+         }
+      } else if (dispose == 2) { 
+         // restore what was changed last frame to background before that frame; 
+         for (pi = 0; pi < pcount; ++pi) {
+            if (g->history[pi]) {
+               memcpy( &g->out[pi * 4], &g->background[pi * 4], 4 ); 
+            }
+         }
+      } else {
+         // This is a non-disposal case eithe way, so just 
+         // leave the pixels as is, and they will become the new background
+         // 1: do not dispose
+         // 0:  not specified.
+      }
+
+      // background is what out is after the undoing of the previou frame; 
+      memcpy( g->background, g->out, 4 * g->w * g->h ); 
+   }
+
+   // clear my history; 
+   memset( g->history, 0x00, g->w * g->h );        // pixels that were affected previous frame
+
+   for (;;) {
+      int tag = stbi__get8(s); 
+      switch (tag) {
+         case 0x2C: /* Image Descriptor */
+         {
+            stbi__int32 x, y, w, h;
+            stbi_uc *o;
+
+            x = stbi__get16le(s);
+            y = stbi__get16le(s);
+            w = stbi__get16le(s);
+            h = stbi__get16le(s);
+            if (((x + w) > (g->w)) || ((y + h) > (g->h)))
+               return stbi__errpuc("bad Image Descriptor", "Corrupt GIF");
+
+            g->line_size = g->w * 4;
+            g->start_x = x * 4;
+            g->start_y = y * g->line_size;
+            g->max_x   = g->start_x + w * 4;
+            g->max_y   = g->start_y + h * g->line_size;
+            g->cur_x   = g->start_x;
+            g->cur_y   = g->start_y;
+
+            g->lflags = stbi__get8(s);
+
+            if (g->lflags & 0x40) {
+               g->step = 8 * g->line_size; // first interlaced spacing
+               g->parse = 3;
+            } else {
+               g->step = g->line_size;
+               g->parse = 0;
+            }
+
+            if (g->lflags & 0x80) {
+               stbi__gif_parse_colortable(s,g->lpal, 2 << (g->lflags & 7), g->eflags & 0x01 ? g->transparent : -1);
+               g->color_table = (stbi_uc *) g->lpal;
+            } else if (g->flags & 0x80) {
+               g->color_table = (stbi_uc *) g->pal;
+            } else
+               return stbi__errpuc("missing color table", "Corrupt GIF");            
+            
+            o = stbi__process_gif_raster(s, g);
+            if (o == NULL) return NULL;
+
+            // if this was the first frame, 
+            pcount = g->w * g->h; 
+            if (first_frame && (g->bgindex > 0)) {
+               // if first frame, any pixel not drawn to gets the background color
+               for (pi = 0; pi < pcount; ++pi) {
+                  if (g->history[pi] == 0) {
+                     g->pal[g->bgindex][3] = 255; // just in case it was made transparent, undo that; It will be reset next frame if need be; 
+                     memcpy( &g->out[pi * 4], &g->pal[g->bgindex], 4 ); 
+                  }
+               }
+            }
+
+            return o;
+         }
+
+         case 0x21: // Comment Extension.
+         {
+            int len;
+            int ext = stbi__get8(s); 
+            if (ext == 0xF9) { // Graphic Control Extension.
+               len = stbi__get8(s);
+               if (len == 4) {
+                  g->eflags = stbi__get8(s);
+                  g->delay = 10 * stbi__get16le(s); // delay - 1/100th of a second, saving as 1/1000ths.
+
+                  // unset old transparent
+                  if (g->transparent >= 0) {
+                     g->pal[g->transparent][3] = 255; 
+                  } 
+                  if (g->eflags & 0x01) {
+                     g->transparent = stbi__get8(s);
+                     if (g->transparent >= 0) {
+                        g->pal[g->transparent][3] = 0; 
+                     }
+                  } else {
+                     // don't need transparent
+                     stbi__skip(s, 1); 
+                     g->transparent = -1; 
+                  }
+               } else {
+                  stbi__skip(s, len);
+                  break;
+               }
+            } 
+            while ((len = stbi__get8(s)) != 0) {
+               stbi__skip(s, len);
+            }
+            break;
+         }
+
+         case 0x3B: // gif stream termination code
+            return (stbi_uc *) s; // using '1' causes warning on some compilers
+
+         default:
+            return stbi__errpuc("unknown code", "Corrupt GIF");
+      }
+   }
+}
+
+static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp)
+{
+   if (stbi__gif_test(s)) {
+      int layers = 0; 
+      stbi_uc *u = 0;
+      stbi_uc *out = 0;
+      stbi_uc *two_back = 0; 
+      stbi__gif g;
+      int stride; 
+      memset(&g, 0, sizeof(g));
+      if (delays) {
+         *delays = 0; 
+      }
+
+      do {
+         u = stbi__gif_load_next(s, &g, comp, req_comp, two_back);
+         if (u == (stbi_uc *) s) u = 0;  // end of animated gif marker
+
+         if (u) {
+            *x = g.w;
+            *y = g.h;
+            ++layers; 
+            stride = g.w * g.h * 4; 
+         
+            if (out) {
+               out = (stbi_uc*) STBI_REALLOC( out, layers * stride ); 
+               if (delays) {
+                  *delays = (int*) STBI_REALLOC( *delays, sizeof(int) * layers ); 
+               }
+            } else {
+               out = (stbi_uc*)stbi__malloc( layers * stride ); 
+               if (delays) {
+                  *delays = (int*) stbi__malloc( layers * sizeof(int) ); 
+               }
+            }
+            memcpy( out + ((layers - 1) * stride), u, stride ); 
+            if (layers >= 2) {
+               two_back = out - 2 * stride; 
+            }
+
+            if (delays) {
+               (*delays)[layers - 1U] = g.delay; 
+            }
+         }
+      } while (u != 0); 
+
+      // free temp buffer; 
+      STBI_FREE(g.out); 
+      STBI_FREE(g.history); 
+      STBI_FREE(g.background); 
+
+      // do the final conversion after loading everything; 
+      if (req_comp && req_comp != 4)
+         out = stbi__convert_format(out, 4, req_comp, layers * g.w, g.h);
+
+      *z = layers; 
+      return out;
+   } else {
+      return stbi__errpuc("not GIF", "Image was not as a gif type."); 
+   }
+}
+
+static void *stbi__gif_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   stbi_uc *u = 0;
+   stbi__gif g;
+   memset(&g, 0, sizeof(g));
+   STBI_NOTUSED(ri);
+
+   u = stbi__gif_load_next(s, &g, comp, req_comp, 0);
+   if (u == (stbi_uc *) s) u = 0;  // end of animated gif marker
+   if (u) {
+      *x = g.w;
+      *y = g.h;
+
+      // moved conversion to after successful load so that the same
+      // can be done for multiple frames. 
+      if (req_comp && req_comp != 4)
+         u = stbi__convert_format(u, 4, req_comp, g.w, g.h);
+   }
+
+   // free buffers needed for multiple frame loading; 
+   STBI_FREE(g.history);
+   STBI_FREE(g.background); 
+
+   return u;
+}
+
+static int stbi__gif_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   return stbi__gif_info_raw(s,x,y,comp);
+}
+#endif
+
+// *************************************************************************************************
+// Radiance RGBE HDR loader
+// originally by Nicolas Schulz
+#ifndef STBI_NO_HDR
+static int stbi__hdr_test_core(stbi__context *s, const char *signature)
+{
+   int i;
+   for (i=0; signature[i]; ++i)
+      if (stbi__get8(s) != signature[i])
+          return 0;
+   stbi__rewind(s);
+   return 1;
+}
+
+static int stbi__hdr_test(stbi__context* s)
+{
+   int r = stbi__hdr_test_core(s, "#?RADIANCE\n");
+   stbi__rewind(s);
+   if(!r) {
+       r = stbi__hdr_test_core(s, "#?RGBE\n");
+       stbi__rewind(s);
+   }
+   return r;
+}
+
+#define STBI__HDR_BUFLEN  1024
+static char *stbi__hdr_gettoken(stbi__context *z, char *buffer)
+{
+   int len=0;
+   char c = '\0';
+
+   c = (char) stbi__get8(z);
+
+   while (!stbi__at_eof(z) && c != '\n') {
+      buffer[len++] = c;
+      if (len == STBI__HDR_BUFLEN-1) {
+         // flush to end of line
+         while (!stbi__at_eof(z) && stbi__get8(z) != '\n')
+            ;
+         break;
+      }
+      c = (char) stbi__get8(z);
+   }
+
+   buffer[len] = 0;
+   return buffer;
+}
+
+static void stbi__hdr_convert(float *output, stbi_uc *input, int req_comp)
+{
+   if ( input[3] != 0 ) {
+      float f1;
+      // Exponent
+      f1 = (float) ldexp(1.0f, input[3] - (int)(128 + 8));
+      if (req_comp <= 2)
+         output[0] = (input[0] + input[1] + input[2]) * f1 / 3;
+      else {
+         output[0] = input[0] * f1;
+         output[1] = input[1] * f1;
+         output[2] = input[2] * f1;
+      }
+      if (req_comp == 2) output[1] = 1;
+      if (req_comp == 4) output[3] = 1;
+   } else {
+      switch (req_comp) {
+         case 4: output[3] = 1; /* fallthrough */
+         case 3: output[0] = output[1] = output[2] = 0;
+                 break;
+         case 2: output[1] = 1; /* fallthrough */
+         case 1: output[0] = 0;
+                 break;
+      }
+   }
+}
+
+static float *stbi__hdr_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   char buffer[STBI__HDR_BUFLEN];
+   char *token;
+   int valid = 0;
+   int width, height;
+   stbi_uc *scanline;
+   float *hdr_data;
+   int len;
+   unsigned char count, value;
+   int i, j, k, c1,c2, z;
+   const char *headerToken;
+   STBI_NOTUSED(ri);
+
+   // Check identifier
+   headerToken = stbi__hdr_gettoken(s,buffer);
+   if (strcmp(headerToken, "#?RADIANCE") != 0 && strcmp(headerToken, "#?RGBE") != 0)
+      return stbi__errpf("not HDR", "Corrupt HDR image");
+
+   // Parse header
+   for(;;) {
+      token = stbi__hdr_gettoken(s,buffer);
+      if (token[0] == 0) break;
+      if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
+   }
+
+   if (!valid)    return stbi__errpf("unsupported format", "Unsupported HDR format");
+
+   // Parse width and height
+   // can't use sscanf() if we're not using stdio!
+   token = stbi__hdr_gettoken(s,buffer);
+   if (strncmp(token, "-Y ", 3))  return stbi__errpf("unsupported data layout", "Unsupported HDR format");
+   token += 3;
+   height = (int) strtol(token, &token, 10);
+   while (*token == ' ') ++token;
+   if (strncmp(token, "+X ", 3))  return stbi__errpf("unsupported data layout", "Unsupported HDR format");
+   token += 3;
+   width = (int) strtol(token, NULL, 10);
+
+   *x = width;
+   *y = height;
+
+   if (comp) *comp = 3;
+   if (req_comp == 0) req_comp = 3;
+
+   if (!stbi__mad4sizes_valid(width, height, req_comp, sizeof(float), 0))
+      return stbi__errpf("too large", "HDR image is too large");
+
+   // Read data
+   hdr_data = (float *) stbi__malloc_mad4(width, height, req_comp, sizeof(float), 0);
+   if (!hdr_data)
+      return stbi__errpf("outofmem", "Out of memory");
+
+   // Load image data
+   // image data is stored as some number of sca
+   if ( width < 8 || width >= 32768) {
+      // Read flat data
+      for (j=0; j < height; ++j) {
+         for (i=0; i < width; ++i) {
+            stbi_uc rgbe[4];
+           main_decode_loop:
+            stbi__getn(s, rgbe, 4);
+            stbi__hdr_convert(hdr_data + j * width * req_comp + i * req_comp, rgbe, req_comp);
+         }
+      }
+   } else {
+      // Read RLE-encoded data
+      scanline = NULL;
+
+      for (j = 0; j < height; ++j) {
+         c1 = stbi__get8(s);
+         c2 = stbi__get8(s);
+         len = stbi__get8(s);
+         if (c1 != 2 || c2 != 2 || (len & 0x80)) {
+            // not run-length encoded, so we have to actually use THIS data as a decoded
+            // pixel (note this can't be a valid pixel--one of RGB must be >= 128)
+            stbi_uc rgbe[4];
+            rgbe[0] = (stbi_uc) c1;
+            rgbe[1] = (stbi_uc) c2;
+            rgbe[2] = (stbi_uc) len;
+            rgbe[3] = (stbi_uc) stbi__get8(s);
+            stbi__hdr_convert(hdr_data, rgbe, req_comp);
+            i = 1;
+            j = 0;
+            STBI_FREE(scanline);
+            goto main_decode_loop; // yes, this makes no sense
+         }
+         len <<= 8;
+         len |= stbi__get8(s);
+         if (len != width) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("invalid decoded scanline length", "corrupt HDR"); }
+         if (scanline == NULL) {
+            scanline = (stbi_uc *) stbi__malloc_mad2(width, 4, 0);
+            if (!scanline) {
+               STBI_FREE(hdr_data);
+               return stbi__errpf("outofmem", "Out of memory");
+            }
+         }
+
+         for (k = 0; k < 4; ++k) {
+            int nleft;
+            i = 0;
+            while ((nleft = width - i) > 0) {
+               count = stbi__get8(s);
+               if (count > 128) {
+                  // Run
+                  value = stbi__get8(s);
+                  count -= 128;
+                  if (count > nleft) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("corrupt", "bad RLE data in HDR"); }
+                  for (z = 0; z < count; ++z)
+                     scanline[i++ * 4 + k] = value;
+               } else {
+                  // Dump
+                  if (count > nleft) { STBI_FREE(hdr_data); STBI_FREE(scanline); return stbi__errpf("corrupt", "bad RLE data in HDR"); }
+                  for (z = 0; z < count; ++z)
+                     scanline[i++ * 4 + k] = stbi__get8(s);
+               }
+            }
+         }
+         for (i=0; i < width; ++i)
+            stbi__hdr_convert(hdr_data+(j*width + i)*req_comp, scanline + i*4, req_comp);
+      }
+      if (scanline)
+         STBI_FREE(scanline);
+   }
+
+   return hdr_data;
+}
+
+static int stbi__hdr_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   char buffer[STBI__HDR_BUFLEN];
+   char *token;
+   int valid = 0;
+   int dummy;
+
+   if (!x) x = &dummy;
+   if (!y) y = &dummy;
+   if (!comp) comp = &dummy;
+
+   if (stbi__hdr_test(s) == 0) {
+       stbi__rewind( s );
+       return 0;
+   }
+
+   for(;;) {
+      token = stbi__hdr_gettoken(s,buffer);
+      if (token[0] == 0) break;
+      if (strcmp(token, "FORMAT=32-bit_rle_rgbe") == 0) valid = 1;
+   }
+
+   if (!valid) {
+       stbi__rewind( s );
+       return 0;
+   }
+   token = stbi__hdr_gettoken(s,buffer);
+   if (strncmp(token, "-Y ", 3)) {
+       stbi__rewind( s );
+       return 0;
+   }
+   token += 3;
+   *y = (int) strtol(token, &token, 10);
+   while (*token == ' ') ++token;
+   if (strncmp(token, "+X ", 3)) {
+       stbi__rewind( s );
+       return 0;
+   }
+   token += 3;
+   *x = (int) strtol(token, NULL, 10);
+   *comp = 3;
+   return 1;
+}
+#endif // STBI_NO_HDR
+
+#ifndef STBI_NO_BMP
+static int stbi__bmp_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   void *p;
+   stbi__bmp_data info;
+
+   info.all_a = 255;
+   p = stbi__bmp_parse_header(s, &info);
+   stbi__rewind( s );
+   if (p == NULL)
+      return 0;
+   if (x) *x = s->img_x;
+   if (y) *y = s->img_y;
+   if (comp) *comp = info.ma ? 4 : 3;
+   return 1;
+}
+#endif
+
+#ifndef STBI_NO_PSD
+static int stbi__psd_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   int channelCount, dummy, depth;
+   if (!x) x = &dummy;
+   if (!y) y = &dummy;
+   if (!comp) comp = &dummy;
+   if (stbi__get32be(s) != 0x38425053) {
+       stbi__rewind( s );
+       return 0;
+   }
+   if (stbi__get16be(s) != 1) {
+       stbi__rewind( s );
+       return 0;
+   }
+   stbi__skip(s, 6);
+   channelCount = stbi__get16be(s);
+   if (channelCount < 0 || channelCount > 16) {
+       stbi__rewind( s );
+       return 0;
+   }
+   *y = stbi__get32be(s);
+   *x = stbi__get32be(s);
+   depth = stbi__get16be(s);
+   if (depth != 8 && depth != 16) {
+       stbi__rewind( s );
+       return 0;
+   }
+   if (stbi__get16be(s) != 3) {
+       stbi__rewind( s );
+       return 0;
+   }
+   *comp = 4;
+   return 1;
+}
+
+static int stbi__psd_is16(stbi__context *s)
+{
+   int channelCount, depth;
+   if (stbi__get32be(s) != 0x38425053) {
+       stbi__rewind( s );
+       return 0;
+   }
+   if (stbi__get16be(s) != 1) {
+       stbi__rewind( s );
+       return 0;
+   }
+   stbi__skip(s, 6);
+   channelCount = stbi__get16be(s);
+   if (channelCount < 0 || channelCount > 16) {
+       stbi__rewind( s );
+       return 0;
+   }
+   (void) stbi__get32be(s);
+   (void) stbi__get32be(s);
+   depth = stbi__get16be(s);
+   if (depth != 16) {
+       stbi__rewind( s );
+       return 0;
+   }
+   return 1;
+}
+#endif
+
+#ifndef STBI_NO_PIC
+static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   int act_comp=0,num_packets=0,chained,dummy;
+   stbi__pic_packet packets[10];
+
+   if (!x) x = &dummy;
+   if (!y) y = &dummy;
+   if (!comp) comp = &dummy;
+
+   if (!stbi__pic_is4(s,"\x53\x80\xF6\x34")) {
+      stbi__rewind(s);
+      return 0;
+   }
+
+   stbi__skip(s, 88);
+
+   *x = stbi__get16be(s);
+   *y = stbi__get16be(s);
+   if (stbi__at_eof(s)) {
+      stbi__rewind( s);
+      return 0;
+   }
+   if ( (*x) != 0 && (1 << 28) / (*x) < (*y)) {
+      stbi__rewind( s );
+      return 0;
+   }
+
+   stbi__skip(s, 8);
+
+   do {
+      stbi__pic_packet *packet;
+
+      if (num_packets==sizeof(packets)/sizeof(packets[0]))
+         return 0;
+
+      packet = &packets[num_packets++];
+      chained = stbi__get8(s);
+      packet->size    = stbi__get8(s);
+      packet->type    = stbi__get8(s);
+      packet->channel = stbi__get8(s);
+      act_comp |= packet->channel;
+
+      if (stbi__at_eof(s)) {
+          stbi__rewind( s );
+          return 0;
+      }
+      if (packet->size != 8) {
+          stbi__rewind( s );
+          return 0;
+      }
+   } while (chained);
+
+   *comp = (act_comp & 0x10 ? 4 : 3);
+
+   return 1;
+}
+#endif
+
+// *************************************************************************************************
+// Portable Gray Map and Portable Pixel Map loader
+// by Ken Miller
+//
+// PGM: http://netpbm.sourceforge.net/doc/pgm.html
+// PPM: http://netpbm.sourceforge.net/doc/ppm.html
+//
+// Known limitations:
+//    Does not support comments in the header section
+//    Does not support ASCII image data (formats P2 and P3)
+//    Does not support 16-bit-per-channel
+
+#ifndef STBI_NO_PNM
+
+static int      stbi__pnm_test(stbi__context *s)
+{
+   char p, t;
+   p = (char) stbi__get8(s);
+   t = (char) stbi__get8(s);
+   if (p != 'P' || (t != '5' && t != '6')) {
+       stbi__rewind( s );
+       return 0;
+   }
+   return 1;
+}
+
+static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri)
+{
+   stbi_uc *out;
+   STBI_NOTUSED(ri);
+
+   if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n))
+      return 0;
+
+   *x = s->img_x;
+   *y = s->img_y;
+   if (comp) *comp = s->img_n;
+
+   if (!stbi__mad3sizes_valid(s->img_n, s->img_x, s->img_y, 0))
+      return stbi__errpuc("too large", "PNM too large");
+
+   out = (stbi_uc *) stbi__malloc_mad3(s->img_n, s->img_x, s->img_y, 0);
+   if (!out) return stbi__errpuc("outofmem", "Out of memory");
+   stbi__getn(s, out, s->img_n * s->img_x * s->img_y);
+
+   if (req_comp && req_comp != s->img_n) {
+      out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y);
+      if (out == NULL) return out; // stbi__convert_format frees input on failure
+   }
+   return out;
+}
+
+static int      stbi__pnm_isspace(char c)
+{
+   return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r';
+}
+
+static void     stbi__pnm_skip_whitespace(stbi__context *s, char *c)
+{
+   for (;;) {
+      while (!stbi__at_eof(s) && stbi__pnm_isspace(*c))
+         *c = (char) stbi__get8(s);
+
+      if (stbi__at_eof(s) || *c != '#')
+         break;
+
+      while (!stbi__at_eof(s) && *c != '\n' && *c != '\r' )
+         *c = (char) stbi__get8(s);
+   }
+}
+
+static int      stbi__pnm_isdigit(char c)
+{
+   return c >= '0' && c <= '9';
+}
+
+static int      stbi__pnm_getinteger(stbi__context *s, char *c)
+{
+   int value = 0;
+
+   while (!stbi__at_eof(s) && stbi__pnm_isdigit(*c)) {
+      value = value*10 + (*c - '0');
+      *c = (char) stbi__get8(s);
+   }
+
+   return value;
+}
+
+static int      stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp)
+{
+   int maxv, dummy;
+   char c, p, t;
+
+   if (!x) x = &dummy;
+   if (!y) y = &dummy;
+   if (!comp) comp = &dummy;
+
+   stbi__rewind(s);
+
+   // Get identifier
+   p = (char) stbi__get8(s);
+   t = (char) stbi__get8(s);
+   if (p != 'P' || (t != '5' && t != '6')) {
+       stbi__rewind(s);
+       return 0;
+   }
+
+   *comp = (t == '6') ? 3 : 1;  // '5' is 1-component .pgm; '6' is 3-component .ppm
+
+   c = (char) stbi__get8(s);
+   stbi__pnm_skip_whitespace(s, &c);
+
+   *x = stbi__pnm_getinteger(s, &c); // read width
+   stbi__pnm_skip_whitespace(s, &c);
+
+   *y = stbi__pnm_getinteger(s, &c); // read height
+   stbi__pnm_skip_whitespace(s, &c);
+
+   maxv = stbi__pnm_getinteger(s, &c);  // read max value
+
+   if (maxv > 255)
+      return stbi__err("max value > 255", "PPM image not 8-bit");
+   else
+      return 1;
+}
+#endif
+
+static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp)
+{
+   #ifndef STBI_NO_JPEG
+   if (stbi__jpeg_info(s, x, y, comp)) return 1;
+   #endif
+
+   #ifndef STBI_NO_PNG
+   if (stbi__png_info(s, x, y, comp))  return 1;
+   #endif
+
+   #ifndef STBI_NO_GIF
+   if (stbi__gif_info(s, x, y, comp))  return 1;
+   #endif
+
+   #ifndef STBI_NO_BMP
+   if (stbi__bmp_info(s, x, y, comp))  return 1;
+   #endif
+
+   #ifndef STBI_NO_PSD
+   if (stbi__psd_info(s, x, y, comp))  return 1;
+   #endif
+
+   #ifndef STBI_NO_PIC
+   if (stbi__pic_info(s, x, y, comp))  return 1;
+   #endif
+
+   #ifndef STBI_NO_PNM
+   if (stbi__pnm_info(s, x, y, comp))  return 1;
+   #endif
+
+   #ifndef STBI_NO_HDR
+   if (stbi__hdr_info(s, x, y, comp))  return 1;
+   #endif
+
+   // test tga last because it's a crappy test!
+   #ifndef STBI_NO_TGA
+   if (stbi__tga_info(s, x, y, comp))
+       return 1;
+   #endif
+   return stbi__err("unknown image type", "Image not of any known type, or corrupt");
+}
+
+static int stbi__is_16_main(stbi__context *s)
+{
+   #ifndef STBI_NO_PNG
+   if (stbi__png_is16(s))  return 1;
+   #endif
+
+   #ifndef STBI_NO_PSD
+   if (stbi__psd_is16(s))  return 1;
+   #endif
+
+   return 0;
+}
+
+#ifndef STBI_NO_STDIO
+STBIDEF int stbi_info(char const *filename, int *x, int *y, int *comp)
+{
+    FILE *f = stbi__fopen(filename, "rb");
+    int result;
+    if (!f) return stbi__err("can't fopen", "Unable to open file");
+    result = stbi_info_from_file(f, x, y, comp);
+    fclose(f);
+    return result;
+}
+
+STBIDEF int stbi_info_from_file(FILE *f, int *x, int *y, int *comp)
+{
+   int r;
+   stbi__context s;
+   long pos = ftell(f);
+   stbi__start_file(&s, f);
+   r = stbi__info_main(&s,x,y,comp);
+   fseek(f,pos,SEEK_SET);
+   return r;
+}
+
+STBIDEF int stbi_is_16_bit(char const *filename)
+{
+    FILE *f = stbi__fopen(filename, "rb");
+    int result;
+    if (!f) return stbi__err("can't fopen", "Unable to open file");
+    result = stbi_is_16_bit_from_file(f);
+    fclose(f);
+    return result;
+}
+
+STBIDEF int stbi_is_16_bit_from_file(FILE *f)
+{
+   int r;
+   stbi__context s;
+   long pos = ftell(f);
+   stbi__start_file(&s, f);
+   r = stbi__is_16_main(&s);
+   fseek(f,pos,SEEK_SET);
+   return r;
+}
+#endif // !STBI_NO_STDIO
+
+STBIDEF int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp)
+{
+   stbi__context s;
+   stbi__start_mem(&s,buffer,len);
+   return stbi__info_main(&s,x,y,comp);
+}
+
+STBIDEF int stbi_info_from_callbacks(stbi_io_callbacks const *c, void *user, int *x, int *y, int *comp)
+{
+   stbi__context s;
+   stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user);
+   return stbi__info_main(&s,x,y,comp);
+}
+
+STBIDEF int stbi_is_16_bit_from_memory(stbi_uc const *buffer, int len)
+{
+   stbi__context s;
+   stbi__start_mem(&s,buffer,len);
+   return stbi__is_16_main(&s);
+}
+
+STBIDEF int stbi_is_16_bit_from_callbacks(stbi_io_callbacks const *c, void *user)
+{
+   stbi__context s;
+   stbi__start_callbacks(&s, (stbi_io_callbacks *) c, user);
+   return stbi__is_16_main(&s);
+}
+
+#endif // STB_IMAGE_IMPLEMENTATION
+
+/*
+   revision history:
+      2.20  (2019-02-07) support utf8 filenames in Windows; fix warnings and platform ifdefs 
+      2.19  (2018-02-11) fix warning
+      2.18  (2018-01-30) fix warnings
+      2.17  (2018-01-29) change sbti__shiftsigned to avoid clang -O2 bug
+                         1-bit BMP
+                         *_is_16_bit api
+                         avoid warnings
+      2.16  (2017-07-23) all functions have 16-bit variants;
+                         STBI_NO_STDIO works again;
+                         compilation fixes;
+                         fix rounding in unpremultiply;
+                         optimize vertical flip;
+                         disable raw_len validation;
+                         documentation fixes
+      2.15  (2017-03-18) fix png-1,2,4 bug; now all Imagenet JPGs decode;
+                         warning fixes; disable run-time SSE detection on gcc;
+                         uniform handling of optional "return" values;
+                         thread-safe initialization of zlib tables
+      2.14  (2017-03-03) remove deprecated STBI_JPEG_OLD; fixes for Imagenet JPGs
+      2.13  (2016-11-29) add 16-bit API, only supported for PNG right now
+      2.12  (2016-04-02) fix typo in 2.11 PSD fix that caused crashes
+      2.11  (2016-04-02) allocate large structures on the stack
+                         remove white matting for transparent PSD
+                         fix reported channel count for PNG & BMP
+                         re-enable SSE2 in non-gcc 64-bit
+                         support RGB-formatted JPEG
+                         read 16-bit PNGs (only as 8-bit)
+      2.10  (2016-01-22) avoid warning introduced in 2.09 by STBI_REALLOC_SIZED
+      2.09  (2016-01-16) allow comments in PNM files
+                         16-bit-per-pixel TGA (not bit-per-component)
+                         info() for TGA could break due to .hdr handling
+                         info() for BMP to shares code instead of sloppy parse
+                         can use STBI_REALLOC_SIZED if allocator doesn't support realloc
+                         code cleanup
+      2.08  (2015-09-13) fix to 2.07 cleanup, reading RGB PSD as RGBA
+      2.07  (2015-09-13) fix compiler warnings
+                         partial animated GIF support
+                         limited 16-bpc PSD support
+                         #ifdef unused functions
+                         bug with < 92 byte PIC,PNM,HDR,TGA
+      2.06  (2015-04-19) fix bug where PSD returns wrong '*comp' value
+      2.05  (2015-04-19) fix bug in progressive JPEG handling, fix warning
+      2.04  (2015-04-15) try to re-enable SIMD on MinGW 64-bit
+      2.03  (2015-04-12) extra corruption checking (mmozeiko)
+                         stbi_set_flip_vertically_on_load (nguillemot)
+                         fix NEON support; fix mingw support
+      2.02  (2015-01-19) fix incorrect assert, fix warning
+      2.01  (2015-01-17) fix various warnings; suppress SIMD on gcc 32-bit without -msse2
+      2.00b (2014-12-25) fix STBI_MALLOC in progressive JPEG
+      2.00  (2014-12-25) optimize JPG, including x86 SSE2 & NEON SIMD (ryg)
+                         progressive JPEG (stb)
+                         PGM/PPM support (Ken Miller)
+                         STBI_MALLOC,STBI_REALLOC,STBI_FREE
+                         GIF bugfix -- seemingly never worked
+                         STBI_NO_*, STBI_ONLY_*
+      1.48  (2014-12-14) fix incorrectly-named assert()
+      1.47  (2014-12-14) 1/2/4-bit PNG support, both direct and paletted (Omar Cornut & stb)
+                         optimize PNG (ryg)
+                         fix bug in interlaced PNG with user-specified channel count (stb)
+      1.46  (2014-08-26)
+              fix broken tRNS chunk (colorkey-style transparency) in non-paletted PNG
+      1.45  (2014-08-16)
+              fix MSVC-ARM internal compiler error by wrapping malloc
+      1.44  (2014-08-07)
+              various warning fixes from Ronny Chevalier
+      1.43  (2014-07-15)
+              fix MSVC-only compiler problem in code changed in 1.42
+      1.42  (2014-07-09)
+              don't define _CRT_SECURE_NO_WARNINGS (affects user code)
+              fixes to stbi__cleanup_jpeg path
+              added STBI_ASSERT to avoid requiring assert.h
+      1.41  (2014-06-25)
+              fix search&replace from 1.36 that messed up comments/error messages
+      1.40  (2014-06-22)
+              fix gcc struct-initialization warning
+      1.39  (2014-06-15)
+              fix to TGA optimization when req_comp != number of components in TGA;
+              fix to GIF loading because BMP wasn't rewinding (whoops, no GIFs in my test suite)
+              add support for BMP version 5 (more ignored fields)
+      1.38  (2014-06-06)
+              suppress MSVC warnings on integer casts truncating values
+              fix accidental rename of 'skip' field of I/O
+      1.37  (2014-06-04)
+              remove duplicate typedef
+      1.36  (2014-06-03)
+              convert to header file single-file library
+              if de-iphone isn't set, load iphone images color-swapped instead of returning NULL
+      1.35  (2014-05-27)
+              various warnings
+              fix broken STBI_SIMD path
+              fix bug where stbi_load_from_file no longer left file pointer in correct place
+              fix broken non-easy path for 32-bit BMP (possibly never used)
+              TGA optimization by Arseny Kapoulkine
+      1.34  (unknown)
+              use STBI_NOTUSED in stbi__resample_row_generic(), fix one more leak in tga failure case
+      1.33  (2011-07-14)
+              make stbi_is_hdr work in STBI_NO_HDR (as specified), minor compiler-friendly improvements
+      1.32  (2011-07-13)
+              support for "info" function for all supported filetypes (SpartanJ)
+      1.31  (2011-06-20)
+              a few more leak fixes, bug in PNG handling (SpartanJ)
+      1.30  (2011-06-11)
+              added ability to load files via callbacks to accomidate custom input streams (Ben Wenger)
+              removed deprecated format-specific test/load functions
+              removed support for installable file formats (stbi_loader) -- would have been broken for IO callbacks anyway
+              error cases in bmp and tga give messages and don't leak (Raymond Barbiero, grisha)
+              fix inefficiency in decoding 32-bit BMP (David Woo)
+      1.29  (2010-08-16)
+              various warning fixes from Aurelien Pocheville
+      1.28  (2010-08-01)
+              fix bug in GIF palette transparency (SpartanJ)
+      1.27  (2010-08-01)
+              cast-to-stbi_uc to fix warnings
+      1.26  (2010-07-24)
+              fix bug in file buffering for PNG reported by SpartanJ
+      1.25  (2010-07-17)
+              refix trans_data warning (Won Chun)
+      1.24  (2010-07-12)
+              perf improvements reading from files on platforms with lock-heavy fgetc()
+              minor perf improvements for jpeg
+              deprecated type-specific functions so we'll get feedback if they're needed
+              attempt to fix trans_data warning (Won Chun)
+      1.23    fixed bug in iPhone support
+      1.22  (2010-07-10)
+              removed image *writing* support
+              stbi_info support from Jetro Lauha
+              GIF support from Jean-Marc Lienher
+              iPhone PNG-extensions from James Brown
+              warning-fixes from Nicolas Schulz and Janez Zemva (i.stbi__err. Janez (U+017D)emva)
+      1.21    fix use of 'stbi_uc' in header (reported by jon blow)
+      1.20    added support for Softimage PIC, by Tom Seddon
+      1.19    bug in interlaced PNG corruption check (found by ryg)
+      1.18  (2008-08-02)
+              fix a threading bug (local mutable static)
+      1.17    support interlaced PNG
+      1.16    major bugfix - stbi__convert_format converted one too many pixels
+      1.15    initialize some fields for thread safety
+      1.14    fix threadsafe conversion bug
+              header-file-only version (#define STBI_HEADER_FILE_ONLY before including)
+      1.13    threadsafe
+      1.12    const qualifiers in the API
+      1.11    Support installable IDCT, colorspace conversion routines
+      1.10    Fixes for 64-bit (don't use "unsigned long")
+              optimized upsampling by Fabian "ryg" Giesen
+      1.09    Fix format-conversion for PSD code (bad global variables!)
+      1.08    Thatcher Ulrich's PSD code integrated by Nicolas Schulz
+      1.07    attempt to fix C++ warning/errors again
+      1.06    attempt to fix C++ warning/errors again
+      1.05    fix TGA loading to return correct *comp and use good luminance calc
+      1.04    default float alpha is 1, not 255; use 'void *' for stbi_image_free
+      1.03    bugfixes to STBI_NO_STDIO, STBI_NO_HDR
+      1.02    support for (subset of) HDR files, float interface for preferred access to them
+      1.01    fix bug: possible bug in handling right-side up bmps... not sure
+              fix bug: the stbi__bmp_load() and stbi__tga_load() functions didn't work at all
+      1.00    interface to zlib that skips zlib header
+      0.99    correct handling of alpha in palette
+      0.98    TGA loader by lonesock; dynamically add loaders (untested)
+      0.97    jpeg errors on too large a file; also catch another malloc failure
+      0.96    fix detection of invalid v value - particleman@mollyrocket forum
+      0.95    during header scan, seek to markers in case of padding
+      0.94    STBI_NO_STDIO to disable stdio usage; rename all #defines the same
+      0.93    handle jpegtran output; verbose errors
+      0.92    read 4,8,16,24,32-bit BMP files of several formats
+      0.91    output 24-bit Windows 3.0 BMP files
+      0.90    fix a few more warnings; bump version number to approach 1.0
+      0.61    bugfixes due to Marc LeBlanc, Christopher Lloyd
+      0.60    fix compiling as c++
+      0.59    fix warnings: merge Dave Moore's -Wall fixes
+      0.58    fix bug: zlib uncompressed mode len/nlen was wrong endian
+      0.57    fix bug: jpg last huffman symbol before marker was >9 bits but less than 16 available
+      0.56    fix bug: zlib uncompressed mode len vs. nlen
+      0.55    fix bug: restart_interval not initialized to 0
+      0.54    allow NULL for 'int *comp'
+      0.53    fix bug in png 3->4; speedup png decoding
+      0.52    png handles req_comp=3,4 directly; minor cleanup; jpeg comments
+      0.51    obey req_comp requests, 1-component jpegs return as 1-component,
+              on 'test' only check type, not whether we support this variant
+      0.50  (2006-11-19)
+              first released version
+*/
+
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
+software, either in source code form or as a compiled binary, for any purpose,
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this
+software dedicate any and all copyright interest in the software to the public
+domain. We make this dedication for the benefit of the public at large and to
+the detriment of our heirs and successors. We intend this dedication to be an
+overt act of relinquishment in perpetuity of all present and future rights to
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/
diff --git a/engine/inc/gltf/stb_image_write.h b/engine/inc/gltf/stb_image_write.h
new file mode 100644
index 00000000..ebaa0c55
--- /dev/null
+++ b/engine/inc/gltf/stb_image_write.h
@@ -0,0 +1,1621 @@
+/* stb_image_write - v1.11 - public domain - http://nothings.org/stb/stb_image_write.h
+   writes out PNG/BMP/TGA/JPEG/HDR images to C stdio - Sean Barrett 2010-2015
+                                     no warranty implied; use at your own risk
+
+   Before #including,
+
+       #define STB_IMAGE_WRITE_IMPLEMENTATION
+
+   in the file that you want to have the implementation.
+
+   Will probably not work correctly with strict-aliasing optimizations.
+
+   If using a modern Microsoft Compiler, non-safe versions of CRT calls may cause 
+   compilation warnings or even errors. To avoid this, also before #including,
+
+       #define STBI_MSC_SECURE_CRT
+
+ABOUT:
+
+   This header file is a library for writing images to C stdio or a callback.
+
+   The PNG output is not optimal; it is 20-50% larger than the file
+   written by a decent optimizing implementation; though providing a custom
+   zlib compress function (see STBIW_ZLIB_COMPRESS) can mitigate that.
+   This library is designed for source code compactness and simplicity,
+   not optimal image file size or run-time performance.
+
+BUILDING:
+
+   You can #define STBIW_ASSERT(x) before the #include to avoid using assert.h.
+   You can #define STBIW_MALLOC(), STBIW_REALLOC(), and STBIW_FREE() to replace
+   malloc,realloc,free.
+   You can #define STBIW_MEMMOVE() to replace memmove()
+   You can #define STBIW_ZLIB_COMPRESS to use a custom zlib-style compress function
+   for PNG compression (instead of the builtin one), it must have the following signature:
+   unsigned char * my_compress(unsigned char *data, int data_len, int *out_len, int quality);
+   The returned data will be freed with STBIW_FREE() (free() by default),
+   so it must be heap allocated with STBIW_MALLOC() (malloc() by default),
+
+UNICODE:
+
+   If compiling for Windows and you wish to use Unicode filenames, compile
+   with
+       #define STBIW_WINDOWS_UTF8
+   and pass utf8-encoded filenames. Call stbiw_convert_wchar_to_utf8 to convert
+   Windows wchar_t filenames to utf8.
+
+USAGE:
+
+   There are five functions, one for each image file format:
+
+     int stbi_write_png(char const *filename, int w, int h, int comp, const void *data, int stride_in_bytes);
+     int stbi_write_bmp(char const *filename, int w, int h, int comp, const void *data);
+     int stbi_write_tga(char const *filename, int w, int h, int comp, const void *data);
+     int stbi_write_jpg(char const *filename, int w, int h, int comp, const void *data, int quality);
+     int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data);
+
+     void stbi_flip_vertically_on_write(int flag); // flag is non-zero to flip data vertically
+
+   There are also five equivalent functions that use an arbitrary write function. You are
+   expected to open/close your file-equivalent before and after calling these:
+
+     int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void  *data, int stride_in_bytes);
+     int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void  *data);
+     int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void  *data);
+     int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data);
+     int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality);
+
+   where the callback is:
+      void stbi_write_func(void *context, void *data, int size);
+
+   You can configure it with these global variables:
+      int stbi_write_tga_with_rle;             // defaults to true; set to 0 to disable RLE
+      int stbi_write_png_compression_level;    // defaults to 8; set to higher for more compression
+      int stbi_write_force_png_filter;         // defaults to -1; set to 0..5 to force a filter mode
+
+
+   You can define STBI_WRITE_NO_STDIO to disable the file variant of these
+   functions, so the library will not use stdio.h at all. However, this will
+   also disable HDR writing, because it requires stdio for formatted output.
+
+   Each function returns 0 on failure and non-0 on success.
+
+   The functions create an image file defined by the parameters. The image
+   is a rectangle of pixels stored from left-to-right, top-to-bottom.
+   Each pixel contains 'comp' channels of data stored interleaved with 8-bits
+   per channel, in the following order: 1=Y, 2=YA, 3=RGB, 4=RGBA. (Y is
+   monochrome color.) The rectangle is 'w' pixels wide and 'h' pixels tall.
+   The *data pointer points to the first byte of the top-left-most pixel.
+   For PNG, "stride_in_bytes" is the distance in bytes from the first byte of
+   a row of pixels to the first byte of the next row of pixels.
+
+   PNG creates output files with the same number of components as the input.
+   The BMP format expands Y to RGB in the file format and does not
+   output alpha.
+
+   PNG supports writing rectangles of data even when the bytes storing rows of
+   data are not consecutive in memory (e.g. sub-rectangles of a larger image),
+   by supplying the stride between the beginning of adjacent rows. The other
+   formats do not. (Thus you cannot write a native-format BMP through the BMP
+   writer, both because it is in BGR order and because it may have padding
+   at the end of the line.)
+
+   PNG allows you to set the deflate compression level by setting the global
+   variable 'stbi_write_png_compression_level' (it defaults to 8).
+
+   HDR expects linear float data. Since the format is always 32-bit rgb(e)
+   data, alpha (if provided) is discarded, and for monochrome data it is
+   replicated across all three channels.
+
+   TGA supports RLE or non-RLE compressed data. To use non-RLE-compressed
+   data, set the global variable 'stbi_write_tga_with_rle' to 0.
+   
+   JPEG does ignore alpha channels in input data; quality is between 1 and 100.
+   Higher quality looks better but results in a bigger image.
+   JPEG baseline (no JPEG progressive).
+
+CREDITS:
+
+
+   Sean Barrett           -    PNG/BMP/TGA 
+   Baldur Karlsson        -    HDR
+   Jean-Sebastien Guay    -    TGA monochrome
+   Tim Kelsey             -    misc enhancements
+   Alan Hickman           -    TGA RLE
+   Emmanuel Julien        -    initial file IO callback implementation
+   Jon Olick              -    original jo_jpeg.cpp code
+   Daniel Gibson          -    integrate JPEG, allow external zlib
+   Aarni Koskela          -    allow choosing PNG filter
+
+   bugfixes:
+      github:Chribba
+      Guillaume Chereau
+      github:jry2
+      github:romigrou
+      Sergio Gonzalez
+      Jonas Karlsson
+      Filip Wasil
+      Thatcher Ulrich
+      github:poppolopoppo
+      Patrick Boettcher
+      github:xeekworx
+      Cap Petschulat
+      Simon Rodriguez
+      Ivan Tikhonov
+      github:ignotion
+      Adam Schackart
+
+LICENSE
+
+  See end of file for license information.
+
+*/
+
+#ifndef INCLUDE_STB_IMAGE_WRITE_H
+#define INCLUDE_STB_IMAGE_WRITE_H
+
+#include <stdlib.h>
+
+// if STB_IMAGE_WRITE_STATIC causes problems, try defining STBIWDEF to 'inline' or 'static inline'
+#ifndef STBIWDEF
+#ifdef STB_IMAGE_WRITE_STATIC
+#define STBIWDEF  static
+#else
+#ifdef __cplusplus
+#define STBIWDEF  extern "C"
+#else
+#define STBIWDEF  extern
+#endif
+#endif
+#endif
+
+#ifndef STB_IMAGE_WRITE_STATIC  // C++ forbids static forward declarations
+extern int stbi_write_tga_with_rle;
+extern int stbi_write_png_compression_level;
+extern int stbi_write_force_png_filter;
+#endif
+
+#ifndef STBI_WRITE_NO_STDIO
+STBIWDEF int stbi_write_png(char const *filename, int w, int h, int comp, const void  *data, int stride_in_bytes);
+STBIWDEF int stbi_write_bmp(char const *filename, int w, int h, int comp, const void  *data);
+STBIWDEF int stbi_write_tga(char const *filename, int w, int h, int comp, const void  *data);
+STBIWDEF int stbi_write_hdr(char const *filename, int w, int h, int comp, const float *data);
+STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void  *data, int quality);
+
+#ifdef STBI_WINDOWS_UTF8
+STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input);
+#endif
+#endif
+
+typedef void stbi_write_func(void *context, void *data, int size);
+
+STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void  *data, int stride_in_bytes);
+STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void  *data);
+STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const void  *data);
+STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int w, int h, int comp, const float *data);
+STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void  *data, int quality);
+
+STBIWDEF void stbi_flip_vertically_on_write(int flip_boolean);
+
+#endif//INCLUDE_STB_IMAGE_WRITE_H
+
+#ifdef STB_IMAGE_WRITE_IMPLEMENTATION
+
+#ifdef _WIN32
+   #ifndef _CRT_SECURE_NO_WARNINGS
+   #define _CRT_SECURE_NO_WARNINGS
+   #endif
+   #ifndef _CRT_NONSTDC_NO_DEPRECATE
+   #define _CRT_NONSTDC_NO_DEPRECATE
+   #endif
+#endif
+
+#ifndef STBI_WRITE_NO_STDIO
+#include <stdio.h>
+#endif // STBI_WRITE_NO_STDIO
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#if defined(STBIW_MALLOC) && defined(STBIW_FREE) && (defined(STBIW_REALLOC) || defined(STBIW_REALLOC_SIZED))
+// ok
+#elif !defined(STBIW_MALLOC) && !defined(STBIW_FREE) && !defined(STBIW_REALLOC) && !defined(STBIW_REALLOC_SIZED)
+// ok
+#else
+#error "Must define all or none of STBIW_MALLOC, STBIW_FREE, and STBIW_REALLOC (or STBIW_REALLOC_SIZED)."
+#endif
+
+#ifndef STBIW_MALLOC
+#define STBIW_MALLOC(sz)        malloc(sz)
+#define STBIW_REALLOC(p,newsz)  realloc(p,newsz)
+#define STBIW_FREE(p)           free(p)
+#endif
+
+#ifndef STBIW_REALLOC_SIZED
+#define STBIW_REALLOC_SIZED(p,oldsz,newsz) STBIW_REALLOC(p,newsz)
+#endif
+
+
+#ifndef STBIW_MEMMOVE
+#define STBIW_MEMMOVE(a,b,sz) memmove(a,b,sz)
+#endif
+
+
+#ifndef STBIW_ASSERT
+#include <assert.h>
+#define STBIW_ASSERT(x) assert(x)
+#endif
+
+#define STBIW_UCHAR(x) (unsigned char) ((x) & 0xff)
+
+#ifdef STB_IMAGE_WRITE_STATIC
+static int stbi__flip_vertically_on_write=0;
+static int stbi_write_png_compression_level = 8;
+static int stbi_write_tga_with_rle = 1;
+static int stbi_write_force_png_filter = -1;
+#else
+int stbi_write_png_compression_level = 8;
+int stbi__flip_vertically_on_write=0;
+int stbi_write_tga_with_rle = 1;
+int stbi_write_force_png_filter = -1;
+#endif
+
+STBIWDEF void stbi_flip_vertically_on_write(int flag)
+{
+   stbi__flip_vertically_on_write = flag;
+}
+
+typedef struct
+{
+   stbi_write_func *func;
+   void *context;
+} stbi__write_context;
+
+// initialize a callback-based context
+static void stbi__start_write_callbacks(stbi__write_context *s, stbi_write_func *c, void *context)
+{
+   s->func    = c;
+   s->context = context;
+}
+
+#ifndef STBI_WRITE_NO_STDIO
+
+static void stbi__stdio_write(void *context, void *data, int size)
+{
+   fwrite(data,1,size,(FILE*) context);
+}
+
+#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+#ifdef __cplusplus
+#define STBIW_EXTERN extern "C"
+#else
+#define STBIW_EXTERN extern
+#endif
+STBIW_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide);
+STBIW_EXTERN __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int cp, unsigned long flags, const wchar_t *widestr, int cchwide, char *str, int cbmb, const char *defchar, int *used_default);
+
+STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input)
+{
+	return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, bufferlen, NULL, NULL);
+}
+#endif
+
+static FILE *stbiw__fopen(char const *filename, char const *mode)
+{
+   FILE *f;
+#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+   wchar_t wMode[64];
+   wchar_t wFilename[1024];
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)))
+      return 0;
+	
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)))
+      return 0;
+
+#if _MSC_VER >= 1400
+	if (0 != _wfopen_s(&f, wFilename, wMode))
+		f = 0;
+#else
+   f = _wfopen(wFilename, wMode);
+#endif
+
+#elif defined(_MSC_VER) && _MSC_VER >= 1400
+   if (0 != fopen_s(&f, filename, mode))
+      f=0;
+#else
+   f = fopen(filename, mode);
+#endif
+   return f;
+}
+
+static int stbi__start_write_file(stbi__write_context *s, const char *filename)
+{
+   FILE *f = stbiw__fopen(filename, "wb");
+   stbi__start_write_callbacks(s, stbi__stdio_write, (void *) f);
+   return f != NULL;
+}
+
+static void stbi__end_write_file(stbi__write_context *s)
+{
+   fclose((FILE *)s->context);
+}
+
+#endif // !STBI_WRITE_NO_STDIO
+
+typedef unsigned int stbiw_uint32;
+typedef int stb_image_write_test[sizeof(stbiw_uint32)==4 ? 1 : -1];
+
+static void stbiw__writefv(stbi__write_context *s, const char *fmt, va_list v)
+{
+   while (*fmt) {
+      switch (*fmt++) {
+         case ' ': break;
+         case '1': { unsigned char x = STBIW_UCHAR(va_arg(v, int));
+                     s->func(s->context,&x,1);
+                     break; }
+         case '2': { int x = va_arg(v,int);
+                     unsigned char b[2];
+                     b[0] = STBIW_UCHAR(x);
+                     b[1] = STBIW_UCHAR(x>>8);
+                     s->func(s->context,b,2);
+                     break; }
+         case '4': { stbiw_uint32 x = va_arg(v,int);
+                     unsigned char b[4];
+                     b[0]=STBIW_UCHAR(x);
+                     b[1]=STBIW_UCHAR(x>>8);
+                     b[2]=STBIW_UCHAR(x>>16);
+                     b[3]=STBIW_UCHAR(x>>24);
+                     s->func(s->context,b,4);
+                     break; }
+         default:
+            STBIW_ASSERT(0);
+            return;
+      }
+   }
+}
+
+static void stbiw__writef(stbi__write_context *s, const char *fmt, ...)
+{
+   va_list v;
+   va_start(v, fmt);
+   stbiw__writefv(s, fmt, v);
+   va_end(v);
+}
+
+static void stbiw__putc(stbi__write_context *s, unsigned char c)
+{
+   s->func(s->context, &c, 1);
+}
+
+static void stbiw__write3(stbi__write_context *s, unsigned char a, unsigned char b, unsigned char c)
+{
+   unsigned char arr[3];
+   arr[0] = a, arr[1] = b, arr[2] = c;
+   s->func(s->context, arr, 3);
+}
+
+static void stbiw__write_pixel(stbi__write_context *s, int rgb_dir, int comp, int write_alpha, int expand_mono, unsigned char *d)
+{
+   unsigned char bg[3] = { 255, 0, 255}, px[3];
+   int k;
+
+   if (write_alpha < 0)
+      s->func(s->context, &d[comp - 1], 1);
+
+   switch (comp) {
+      case 2: // 2 pixels = mono + alpha, alpha is written separately, so same as 1-channel case
+      case 1:
+         if (expand_mono)
+            stbiw__write3(s, d[0], d[0], d[0]); // monochrome bmp
+         else
+            s->func(s->context, d, 1);  // monochrome TGA
+         break;
+      case 4:
+         if (!write_alpha) {
+            // composite against pink background
+            for (k = 0; k < 3; ++k)
+               px[k] = bg[k] + ((d[k] - bg[k]) * d[3]) / 255;
+            stbiw__write3(s, px[1 - rgb_dir], px[1], px[1 + rgb_dir]);
+            break;
+         }
+         /* FALLTHROUGH */
+      case 3:
+         stbiw__write3(s, d[1 - rgb_dir], d[1], d[1 + rgb_dir]);
+         break;
+   }
+   if (write_alpha > 0)
+      s->func(s->context, &d[comp - 1], 1);
+}
+
+static void stbiw__write_pixels(stbi__write_context *s, int rgb_dir, int vdir, int x, int y, int comp, void *data, int write_alpha, int scanline_pad, int expand_mono)
+{
+   stbiw_uint32 zero = 0;
+   int i,j, j_end;
+
+   if (y <= 0)
+      return;
+
+   if (stbi__flip_vertically_on_write)
+      vdir *= -1;
+
+   if (vdir < 0)
+      j_end = -1, j = y-1;
+   else
+      j_end =  y, j = 0;
+
+   for (; j != j_end; j += vdir) {
+      for (i=0; i < x; ++i) {
+         unsigned char *d = (unsigned char *) data + (j*x+i)*comp;
+         stbiw__write_pixel(s, rgb_dir, comp, write_alpha, expand_mono, d);
+      }
+      s->func(s->context, &zero, scanline_pad);
+   }
+}
+
+static int stbiw__outfile(stbi__write_context *s, int rgb_dir, int vdir, int x, int y, int comp, int expand_mono, void *data, int alpha, int pad, const char *fmt, ...)
+{
+   if (y < 0 || x < 0) {
+      return 0;
+   } else {
+      va_list v;
+      va_start(v, fmt);
+      stbiw__writefv(s, fmt, v);
+      va_end(v);
+      stbiw__write_pixels(s,rgb_dir,vdir,x,y,comp,data,alpha,pad, expand_mono);
+      return 1;
+   }
+}
+
+static int stbi_write_bmp_core(stbi__write_context *s, int x, int y, int comp, const void *data)
+{
+   int pad = (-x*3) & 3;
+   return stbiw__outfile(s,-1,-1,x,y,comp,1,(void *) data,0,pad,
+           "11 4 22 4" "4 44 22 444444",
+           'B', 'M', 14+40+(x*3+pad)*y, 0,0, 14+40,  // file header
+            40, x,y, 1,24, 0,0,0,0,0,0);             // bitmap header
+}
+
+STBIWDEF int stbi_write_bmp_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data)
+{
+   stbi__write_context s;
+   stbi__start_write_callbacks(&s, func, context);
+   return stbi_write_bmp_core(&s, x, y, comp, data);
+}
+
+#ifndef STBI_WRITE_NO_STDIO
+STBIWDEF int stbi_write_bmp(char const *filename, int x, int y, int comp, const void *data)
+{
+   stbi__write_context s;
+   if (stbi__start_write_file(&s,filename)) {
+      int r = stbi_write_bmp_core(&s, x, y, comp, data);
+      stbi__end_write_file(&s);
+      return r;
+   } else
+      return 0;
+}
+#endif //!STBI_WRITE_NO_STDIO
+
+static int stbi_write_tga_core(stbi__write_context *s, int x, int y, int comp, void *data)
+{
+   int has_alpha = (comp == 2 || comp == 4);
+   int colorbytes = has_alpha ? comp-1 : comp;
+   int format = colorbytes < 2 ? 3 : 2; // 3 color channels (RGB/RGBA) = 2, 1 color channel (Y/YA) = 3
+
+   if (y < 0 || x < 0)
+      return 0;
+
+   if (!stbi_write_tga_with_rle) {
+      return stbiw__outfile(s, -1, -1, x, y, comp, 0, (void *) data, has_alpha, 0,
+         "111 221 2222 11", 0, 0, format, 0, 0, 0, 0, 0, x, y, (colorbytes + has_alpha) * 8, has_alpha * 8);
+   } else {
+      int i,j,k;
+      int jend, jdir;
+
+      stbiw__writef(s, "111 221 2222 11", 0,0,format+8, 0,0,0, 0,0,x,y, (colorbytes + has_alpha) * 8, has_alpha * 8);
+
+      if (stbi__flip_vertically_on_write) {
+         j = 0;
+         jend = y;
+         jdir = 1;
+      } else {
+         j = y-1;
+         jend = -1;
+         jdir = -1;
+      }
+      for (; j != jend; j += jdir) {
+         unsigned char *row = (unsigned char *) data + j * x * comp;
+         int len;
+
+         for (i = 0; i < x; i += len) {
+            unsigned char *begin = row + i * comp;
+            int diff = 1;
+            len = 1;
+
+            if (i < x - 1) {
+               ++len;
+               diff = memcmp(begin, row + (i + 1) * comp, comp);
+               if (diff) {
+                  const unsigned char *prev = begin;
+                  for (k = i + 2; k < x && len < 128; ++k) {
+                     if (memcmp(prev, row + k * comp, comp)) {
+                        prev += comp;
+                        ++len;
+                     } else {
+                        --len;
+                        break;
+                     }
+                  }
+               } else {
+                  for (k = i + 2; k < x && len < 128; ++k) {
+                     if (!memcmp(begin, row + k * comp, comp)) {
+                        ++len;
+                     } else {
+                        break;
+                     }
+                  }
+               }
+            }
+
+            if (diff) {
+               unsigned char header = STBIW_UCHAR(len - 1);
+               s->func(s->context, &header, 1);
+               for (k = 0; k < len; ++k) {
+                  stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin + k * comp);
+               }
+            } else {
+               unsigned char header = STBIW_UCHAR(len - 129);
+               s->func(s->context, &header, 1);
+               stbiw__write_pixel(s, -1, comp, has_alpha, 0, begin);
+            }
+         }
+      }
+   }
+   return 1;
+}
+
+STBIWDEF int stbi_write_tga_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data)
+{
+   stbi__write_context s;
+   stbi__start_write_callbacks(&s, func, context);
+   return stbi_write_tga_core(&s, x, y, comp, (void *) data);
+}
+
+#ifndef STBI_WRITE_NO_STDIO
+STBIWDEF int stbi_write_tga(char const *filename, int x, int y, int comp, const void *data)
+{
+   stbi__write_context s;
+   if (stbi__start_write_file(&s,filename)) {
+      int r = stbi_write_tga_core(&s, x, y, comp, (void *) data);
+      stbi__end_write_file(&s);
+      return r;
+   } else
+      return 0;
+}
+#endif
+
+// *************************************************************************************************
+// Radiance RGBE HDR writer
+// by Baldur Karlsson
+
+#define stbiw__max(a, b)  ((a) > (b) ? (a) : (b))
+
+static void stbiw__linear_to_rgbe(unsigned char *rgbe, float *linear)
+{
+   int exponent;
+   float maxcomp = stbiw__max(linear[0], stbiw__max(linear[1], linear[2]));
+
+   if (maxcomp < 1e-32f) {
+      rgbe[0] = rgbe[1] = rgbe[2] = rgbe[3] = 0;
+   } else {
+      float normalize = (float) frexp(maxcomp, &exponent) * 256.0f/maxcomp;
+
+      rgbe[0] = (unsigned char)(linear[0] * normalize);
+      rgbe[1] = (unsigned char)(linear[1] * normalize);
+      rgbe[2] = (unsigned char)(linear[2] * normalize);
+      rgbe[3] = (unsigned char)(exponent + 128);
+   }
+}
+
+static void stbiw__write_run_data(stbi__write_context *s, int length, unsigned char databyte)
+{
+   unsigned char lengthbyte = STBIW_UCHAR(length+128);
+   STBIW_ASSERT(length+128 <= 255);
+   s->func(s->context, &lengthbyte, 1);
+   s->func(s->context, &databyte, 1);
+}
+
+static void stbiw__write_dump_data(stbi__write_context *s, int length, unsigned char *data)
+{
+   unsigned char lengthbyte = STBIW_UCHAR(length);
+   STBIW_ASSERT(length <= 128); // inconsistent with spec but consistent with official code
+   s->func(s->context, &lengthbyte, 1);
+   s->func(s->context, data, length);
+}
+
+static void stbiw__write_hdr_scanline(stbi__write_context *s, int width, int ncomp, unsigned char *scratch, float *scanline)
+{
+   unsigned char scanlineheader[4] = { 2, 2, 0, 0 };
+   unsigned char rgbe[4];
+   float linear[3];
+   int x;
+
+   scanlineheader[2] = (width&0xff00)>>8;
+   scanlineheader[3] = (width&0x00ff);
+
+   /* skip RLE for images too small or large */
+   if (width < 8 || width >= 32768) {
+      for (x=0; x < width; x++) {
+         switch (ncomp) {
+            case 4: /* fallthrough */
+            case 3: linear[2] = scanline[x*ncomp + 2];
+                    linear[1] = scanline[x*ncomp + 1];
+                    linear[0] = scanline[x*ncomp + 0];
+                    break;
+            default:
+                    linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0];
+                    break;
+         }
+         stbiw__linear_to_rgbe(rgbe, linear);
+         s->func(s->context, rgbe, 4);
+      }
+   } else {
+      int c,r;
+      /* encode into scratch buffer */
+      for (x=0; x < width; x++) {
+         switch(ncomp) {
+            case 4: /* fallthrough */
+            case 3: linear[2] = scanline[x*ncomp + 2];
+                    linear[1] = scanline[x*ncomp + 1];
+                    linear[0] = scanline[x*ncomp + 0];
+                    break;
+            default:
+                    linear[0] = linear[1] = linear[2] = scanline[x*ncomp + 0];
+                    break;
+         }
+         stbiw__linear_to_rgbe(rgbe, linear);
+         scratch[x + width*0] = rgbe[0];
+         scratch[x + width*1] = rgbe[1];
+         scratch[x + width*2] = rgbe[2];
+         scratch[x + width*3] = rgbe[3];
+      }
+
+      s->func(s->context, scanlineheader, 4);
+
+      /* RLE each component separately */
+      for (c=0; c < 4; c++) {
+         unsigned char *comp = &scratch[width*c];
+
+         x = 0;
+         while (x < width) {
+            // find first run
+            r = x;
+            while (r+2 < width) {
+               if (comp[r] == comp[r+1] && comp[r] == comp[r+2])
+                  break;
+               ++r;
+            }
+            if (r+2 >= width)
+               r = width;
+            // dump up to first run
+            while (x < r) {
+               int len = r-x;
+               if (len > 128) len = 128;
+               stbiw__write_dump_data(s, len, &comp[x]);
+               x += len;
+            }
+            // if there's a run, output it
+            if (r+2 < width) { // same test as what we break out of in search loop, so only true if we break'd
+               // find next byte after run
+               while (r < width && comp[r] == comp[x])
+                  ++r;
+               // output run up to r
+               while (x < r) {
+                  int len = r-x;
+                  if (len > 127) len = 127;
+                  stbiw__write_run_data(s, len, comp[x]);
+                  x += len;
+               }
+            }
+         }
+      }
+   }
+}
+
+static int stbi_write_hdr_core(stbi__write_context *s, int x, int y, int comp, float *data)
+{
+   if (y <= 0 || x <= 0 || data == NULL)
+      return 0;
+   else {
+      // Each component is stored separately. Allocate scratch space for full output scanline.
+      unsigned char *scratch = (unsigned char *) STBIW_MALLOC(x*4);
+      int i, len;
+      char buffer[128];
+      char header[] = "#?RADIANCE\n# Written by stb_image_write.h\nFORMAT=32-bit_rle_rgbe\n";
+      s->func(s->context, header, sizeof(header)-1);
+
+#ifdef STBI_MSC_SECURE_CRT
+      len = sprintf_s(buffer, "EXPOSURE=          1.0000000000000\n\n-Y %d +X %d\n", y, x);
+#else
+      len = sprintf(buffer, "EXPOSURE=          1.0000000000000\n\n-Y %d +X %d\n", y, x);
+#endif
+      s->func(s->context, buffer, len);
+
+      for(i=0; i < y; i++)
+         stbiw__write_hdr_scanline(s, x, comp, scratch, data + comp*x*(stbi__flip_vertically_on_write ? y-1-i : i));
+      STBIW_FREE(scratch);
+      return 1;
+   }
+}
+
+STBIWDEF int stbi_write_hdr_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const float *data)
+{
+   stbi__write_context s;
+   stbi__start_write_callbacks(&s, func, context);
+   return stbi_write_hdr_core(&s, x, y, comp, (float *) data);
+}
+
+#ifndef STBI_WRITE_NO_STDIO
+STBIWDEF int stbi_write_hdr(char const *filename, int x, int y, int comp, const float *data)
+{
+   stbi__write_context s;
+   if (stbi__start_write_file(&s,filename)) {
+      int r = stbi_write_hdr_core(&s, x, y, comp, (float *) data);
+      stbi__end_write_file(&s);
+      return r;
+   } else
+      return 0;
+}
+#endif // STBI_WRITE_NO_STDIO
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// PNG writer
+//
+
+#ifndef STBIW_ZLIB_COMPRESS
+// stretchy buffer; stbiw__sbpush() == vector<>::push_back() -- stbiw__sbcount() == vector<>::size()
+#define stbiw__sbraw(a) ((int *) (a) - 2)
+#define stbiw__sbm(a)   stbiw__sbraw(a)[0]
+#define stbiw__sbn(a)   stbiw__sbraw(a)[1]
+
+#define stbiw__sbneedgrow(a,n)  ((a)==0 || stbiw__sbn(a)+n >= stbiw__sbm(a))
+#define stbiw__sbmaybegrow(a,n) (stbiw__sbneedgrow(a,(n)) ? stbiw__sbgrow(a,n) : 0)
+#define stbiw__sbgrow(a,n)  stbiw__sbgrowf((void **) &(a), (n), sizeof(*(a)))
+
+#define stbiw__sbpush(a, v)      (stbiw__sbmaybegrow(a,1), (a)[stbiw__sbn(a)++] = (v))
+#define stbiw__sbcount(a)        ((a) ? stbiw__sbn(a) : 0)
+#define stbiw__sbfree(a)         ((a) ? STBIW_FREE(stbiw__sbraw(a)),0 : 0)
+
+static void *stbiw__sbgrowf(void **arr, int increment, int itemsize)
+{
+   int m = *arr ? 2*stbiw__sbm(*arr)+increment : increment+1;
+   void *p = STBIW_REALLOC_SIZED(*arr ? stbiw__sbraw(*arr) : 0, *arr ? (stbiw__sbm(*arr)*itemsize + sizeof(int)*2) : 0, itemsize * m + sizeof(int)*2);
+   STBIW_ASSERT(p);
+   if (p) {
+      if (!*arr) ((int *) p)[1] = 0;
+      *arr = (void *) ((int *) p + 2);
+      stbiw__sbm(*arr) = m;
+   }
+   return *arr;
+}
+
+static unsigned char *stbiw__zlib_flushf(unsigned char *data, unsigned int *bitbuffer, int *bitcount)
+{
+   while (*bitcount >= 8) {
+      stbiw__sbpush(data, STBIW_UCHAR(*bitbuffer));
+      *bitbuffer >>= 8;
+      *bitcount -= 8;
+   }
+   return data;
+}
+
+static int stbiw__zlib_bitrev(int code, int codebits)
+{
+   int res=0;
+   while (codebits--) {
+      res = (res << 1) | (code & 1);
+      code >>= 1;
+   }
+   return res;
+}
+
+static unsigned int stbiw__zlib_countm(unsigned char *a, unsigned char *b, int limit)
+{
+   int i;
+   for (i=0; i < limit && i < 258; ++i)
+      if (a[i] != b[i]) break;
+   return i;
+}
+
+static unsigned int stbiw__zhash(unsigned char *data)
+{
+   stbiw_uint32 hash = data[0] + (data[1] << 8) + (data[2] << 16);
+   hash ^= hash << 3;
+   hash += hash >> 5;
+   hash ^= hash << 4;
+   hash += hash >> 17;
+   hash ^= hash << 25;
+   hash += hash >> 6;
+   return hash;
+}
+
+#define stbiw__zlib_flush() (out = stbiw__zlib_flushf(out, &bitbuf, &bitcount))
+#define stbiw__zlib_add(code,codebits) \
+      (bitbuf |= (code) << bitcount, bitcount += (codebits), stbiw__zlib_flush())
+#define stbiw__zlib_huffa(b,c)  stbiw__zlib_add(stbiw__zlib_bitrev(b,c),c)
+// default huffman tables
+#define stbiw__zlib_huff1(n)  stbiw__zlib_huffa(0x30 + (n), 8)
+#define stbiw__zlib_huff2(n)  stbiw__zlib_huffa(0x190 + (n)-144, 9)
+#define stbiw__zlib_huff3(n)  stbiw__zlib_huffa(0 + (n)-256,7)
+#define stbiw__zlib_huff4(n)  stbiw__zlib_huffa(0xc0 + (n)-280,8)
+#define stbiw__zlib_huff(n)  ((n) <= 143 ? stbiw__zlib_huff1(n) : (n) <= 255 ? stbiw__zlib_huff2(n) : (n) <= 279 ? stbiw__zlib_huff3(n) : stbiw__zlib_huff4(n))
+#define stbiw__zlib_huffb(n) ((n) <= 143 ? stbiw__zlib_huff1(n) : stbiw__zlib_huff2(n))
+
+#define stbiw__ZHASH   16384
+
+#endif // STBIW_ZLIB_COMPRESS
+
+STBIWDEF unsigned char * stbi_zlib_compress(unsigned char *data, int data_len, int *out_len, int quality)
+{
+#ifdef STBIW_ZLIB_COMPRESS
+   // user provided a zlib compress implementation, use that
+   return STBIW_ZLIB_COMPRESS(data, data_len, out_len, quality);
+#else // use builtin
+   static unsigned short lengthc[] = { 3,4,5,6,7,8,9,10,11,13,15,17,19,23,27,31,35,43,51,59,67,83,99,115,131,163,195,227,258, 259 };
+   static unsigned char  lengtheb[]= { 0,0,0,0,0,0,0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4,  4,  5,  5,  5,  5,  0 };
+   static unsigned short distc[]   = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193,257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577, 32768 };
+   static unsigned char  disteb[]  = { 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13 };
+   unsigned int bitbuf=0;
+   int i,j, bitcount=0;
+   unsigned char *out = NULL;
+   unsigned char ***hash_table = (unsigned char***) STBIW_MALLOC(stbiw__ZHASH * sizeof(char**));
+   if (hash_table == NULL)
+      return NULL;
+   if (quality < 5) quality = 5;
+
+   stbiw__sbpush(out, 0x78);   // DEFLATE 32K window
+   stbiw__sbpush(out, 0x5e);   // FLEVEL = 1
+   stbiw__zlib_add(1,1);  // BFINAL = 1
+   stbiw__zlib_add(1,2);  // BTYPE = 1 -- fixed huffman
+
+   for (i=0; i < stbiw__ZHASH; ++i)
+      hash_table[i] = NULL;
+
+   i=0;
+   while (i < data_len-3) {
+      // hash next 3 bytes of data to be compressed
+      int h = stbiw__zhash(data+i)&(stbiw__ZHASH-1), best=3;
+      unsigned char *bestloc = 0;
+      unsigned char **hlist = hash_table[h];
+      int n = stbiw__sbcount(hlist);
+      for (j=0; j < n; ++j) {
+         if (hlist[j]-data > i-32768) { // if entry lies within window
+            int d = stbiw__zlib_countm(hlist[j], data+i, data_len-i);
+            if (d >= best) best=d,bestloc=hlist[j];
+         }
+      }
+      // when hash table entry is too long, delete half the entries
+      if (hash_table[h] && stbiw__sbn(hash_table[h]) == 2*quality) {
+         STBIW_MEMMOVE(hash_table[h], hash_table[h]+quality, sizeof(hash_table[h][0])*quality);
+         stbiw__sbn(hash_table[h]) = quality;
+      }
+      stbiw__sbpush(hash_table[h],data+i);
+
+      if (bestloc) {
+         // "lazy matching" - check match at *next* byte, and if it's better, do cur byte as literal
+         h = stbiw__zhash(data+i+1)&(stbiw__ZHASH-1);
+         hlist = hash_table[h];
+         n = stbiw__sbcount(hlist);
+         for (j=0; j < n; ++j) {
+            if (hlist[j]-data > i-32767) {
+               int e = stbiw__zlib_countm(hlist[j], data+i+1, data_len-i-1);
+               if (e > best) { // if next match is better, bail on current match
+                  bestloc = NULL;
+                  break;
+               }
+            }
+         }
+      }
+
+      if (bestloc) {
+         int d = (int) (data+i - bestloc); // distance back
+         STBIW_ASSERT(d <= 32767 && best <= 258);
+         for (j=0; best > lengthc[j+1]-1; ++j);
+         stbiw__zlib_huff(j+257);
+         if (lengtheb[j]) stbiw__zlib_add(best - lengthc[j], lengtheb[j]);
+         for (j=0; d > distc[j+1]-1; ++j);
+         stbiw__zlib_add(stbiw__zlib_bitrev(j,5),5);
+         if (disteb[j]) stbiw__zlib_add(d - distc[j], disteb[j]);
+         i += best;
+      } else {
+         stbiw__zlib_huffb(data[i]);
+         ++i;
+      }
+   }
+   // write out final bytes
+   for (;i < data_len; ++i)
+      stbiw__zlib_huffb(data[i]);
+   stbiw__zlib_huff(256); // end of block
+   // pad with 0 bits to byte boundary
+   while (bitcount)
+      stbiw__zlib_add(0,1);
+
+   for (i=0; i < stbiw__ZHASH; ++i)
+      (void) stbiw__sbfree(hash_table[i]);
+   STBIW_FREE(hash_table);
+
+   {
+      // compute adler32 on input
+      unsigned int s1=1, s2=0;
+      int blocklen = (int) (data_len % 5552);
+      j=0;
+      while (j < data_len) {
+         for (i=0; i < blocklen; ++i) s1 += data[j+i], s2 += s1;
+         s1 %= 65521, s2 %= 65521;
+         j += blocklen;
+         blocklen = 5552;
+      }
+      stbiw__sbpush(out, STBIW_UCHAR(s2 >> 8));
+      stbiw__sbpush(out, STBIW_UCHAR(s2));
+      stbiw__sbpush(out, STBIW_UCHAR(s1 >> 8));
+      stbiw__sbpush(out, STBIW_UCHAR(s1));
+   }
+   *out_len = stbiw__sbn(out);
+   // make returned pointer freeable
+   STBIW_MEMMOVE(stbiw__sbraw(out), out, *out_len);
+   return (unsigned char *) stbiw__sbraw(out);
+#endif // STBIW_ZLIB_COMPRESS
+}
+
+static unsigned int stbiw__crc32(unsigned char *buffer, int len)
+{
+#ifdef STBIW_CRC32
+    return STBIW_CRC32(buffer, len);
+#else
+   static unsigned int crc_table[256] =
+   {
+      0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
+      0x0eDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
+      0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
+      0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
+      0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
+      0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
+      0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
+      0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
+      0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
+      0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
+      0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
+      0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
+      0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
+      0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
+      0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
+      0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
+      0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
+      0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
+      0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
+      0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
+      0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
+      0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
+      0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
+      0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
+      0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
+      0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
+      0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
+      0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
+      0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
+      0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
+      0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
+      0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
+   };
+
+   unsigned int crc = ~0u;
+   int i;
+   for (i=0; i < len; ++i)
+      crc = (crc >> 8) ^ crc_table[buffer[i] ^ (crc & 0xff)];
+   return ~crc;
+#endif
+}
+
+#define stbiw__wpng4(o,a,b,c,d) ((o)[0]=STBIW_UCHAR(a),(o)[1]=STBIW_UCHAR(b),(o)[2]=STBIW_UCHAR(c),(o)[3]=STBIW_UCHAR(d),(o)+=4)
+#define stbiw__wp32(data,v) stbiw__wpng4(data, (v)>>24,(v)>>16,(v)>>8,(v));
+#define stbiw__wptag(data,s) stbiw__wpng4(data, s[0],s[1],s[2],s[3])
+
+static void stbiw__wpcrc(unsigned char **data, int len)
+{
+   unsigned int crc = stbiw__crc32(*data - len - 4, len+4);
+   stbiw__wp32(*data, crc);
+}
+
+static unsigned char stbiw__paeth(int a, int b, int c)
+{
+   int p = a + b - c, pa = abs(p-a), pb = abs(p-b), pc = abs(p-c);
+   if (pa <= pb && pa <= pc) return STBIW_UCHAR(a);
+   if (pb <= pc) return STBIW_UCHAR(b);
+   return STBIW_UCHAR(c);
+}
+
+// @OPTIMIZE: provide an option that always forces left-predict or paeth predict
+static void stbiw__encode_png_line(unsigned char *pixels, int stride_bytes, int width, int height, int y, int n, int filter_type, signed char *line_buffer)
+{
+   static int mapping[] = { 0,1,2,3,4 };
+   static int firstmap[] = { 0,1,0,5,6 };
+   int *mymap = (y != 0) ? mapping : firstmap;
+   int i;
+   int type = mymap[filter_type];
+   unsigned char *z = pixels + stride_bytes * (stbi__flip_vertically_on_write ? height-1-y : y);
+   int signed_stride = stbi__flip_vertically_on_write ? -stride_bytes : stride_bytes;
+    
+   if (type==0) {
+      memcpy(line_buffer, z, width*n);
+      return;
+   }
+
+   // first loop isn't optimized since it's just one pixel    
+   for (i = 0; i < n; ++i) {
+      switch (type) {
+         case 1: line_buffer[i] = z[i]; break;
+         case 2: line_buffer[i] = z[i] - z[i-signed_stride]; break;
+         case 3: line_buffer[i] = z[i] - (z[i-signed_stride]>>1); break;
+         case 4: line_buffer[i] = (signed char) (z[i] - stbiw__paeth(0,z[i-signed_stride],0)); break;
+         case 5: line_buffer[i] = z[i]; break;
+         case 6: line_buffer[i] = z[i]; break;
+      }
+   }
+   switch (type) {
+      case 1: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - z[i-n]; break;
+      case 2: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - z[i-signed_stride]; break;
+      case 3: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - ((z[i-n] + z[i-signed_stride])>>1); break;
+      case 4: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - stbiw__paeth(z[i-n], z[i-signed_stride], z[i-signed_stride-n]); break;
+      case 5: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - (z[i-n]>>1); break;
+      case 6: for (i=n; i < width*n; ++i) line_buffer[i] = z[i] - stbiw__paeth(z[i-n], 0,0); break;
+   }
+}
+
+STBIWDEF unsigned char *stbi_write_png_to_mem(const unsigned char *pixels, int stride_bytes, int x, int y, int n, int *out_len)
+{
+   int force_filter = stbi_write_force_png_filter;
+   int ctype[5] = { -1, 0, 4, 2, 6 };
+   unsigned char sig[8] = { 137,80,78,71,13,10,26,10 };
+   unsigned char *out,*o, *filt, *zlib;
+   signed char *line_buffer;
+   int j,zlen;
+
+   if (stride_bytes == 0)
+      stride_bytes = x * n;
+
+   if (force_filter >= 5) {
+      force_filter = -1;
+   }
+
+   filt = (unsigned char *) STBIW_MALLOC((x*n+1) * y); if (!filt) return 0;
+   line_buffer = (signed char *) STBIW_MALLOC(x * n); if (!line_buffer) { STBIW_FREE(filt); return 0; }
+   for (j=0; j < y; ++j) {
+      int filter_type;
+      if (force_filter > -1) {
+         filter_type = force_filter;
+         stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, force_filter, line_buffer);
+      } else { // Estimate the best filter by running through all of them:
+         int best_filter = 0, best_filter_val = 0x7fffffff, est, i;
+         for (filter_type = 0; filter_type < 5; filter_type++) {
+            stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, filter_type, line_buffer);
+
+            // Estimate the entropy of the line using this filter; the less, the better.
+            est = 0;
+            for (i = 0; i < x*n; ++i) {
+               est += abs((signed char) line_buffer[i]);
+            }
+            if (est < best_filter_val) {
+               best_filter_val = est;
+               best_filter = filter_type;
+            }
+         }
+         if (filter_type != best_filter) {  // If the last iteration already got us the best filter, don't redo it
+            stbiw__encode_png_line((unsigned char*)(pixels), stride_bytes, x, y, j, n, best_filter, line_buffer);
+            filter_type = best_filter;
+         }
+      }
+      // when we get here, filter_type contains the filter type, and line_buffer contains the data
+      filt[j*(x*n+1)] = (unsigned char) filter_type;
+      STBIW_MEMMOVE(filt+j*(x*n+1)+1, line_buffer, x*n);
+   }
+   STBIW_FREE(line_buffer);
+   zlib = stbi_zlib_compress(filt, y*( x*n+1), &zlen, stbi_write_png_compression_level);
+   STBIW_FREE(filt);
+   if (!zlib) return 0;
+
+   // each tag requires 12 bytes of overhead
+   out = (unsigned char *) STBIW_MALLOC(8 + 12+13 + 12+zlen + 12);
+   if (!out) return 0;
+   *out_len = 8 + 12+13 + 12+zlen + 12;
+
+   o=out;
+   STBIW_MEMMOVE(o,sig,8); o+= 8;
+   stbiw__wp32(o, 13); // header length
+   stbiw__wptag(o, "IHDR");
+   stbiw__wp32(o, x);
+   stbiw__wp32(o, y);
+   *o++ = 8;
+   *o++ = STBIW_UCHAR(ctype[n]);
+   *o++ = 0;
+   *o++ = 0;
+   *o++ = 0;
+   stbiw__wpcrc(&o,13);
+
+   stbiw__wp32(o, zlen);
+   stbiw__wptag(o, "IDAT");
+   STBIW_MEMMOVE(o, zlib, zlen);
+   o += zlen;
+   STBIW_FREE(zlib);
+   stbiw__wpcrc(&o, zlen);
+
+   stbiw__wp32(o,0);
+   stbiw__wptag(o, "IEND");
+   stbiw__wpcrc(&o,0);
+
+   STBIW_ASSERT(o == out + *out_len);
+
+   return out;
+}
+
+#ifndef STBI_WRITE_NO_STDIO
+STBIWDEF int stbi_write_png(char const *filename, int x, int y, int comp, const void *data, int stride_bytes)
+{
+   FILE *f;
+   int len;
+   unsigned char *png = stbi_write_png_to_mem((const unsigned char *) data, stride_bytes, x, y, comp, &len);
+   if (png == NULL) return 0;
+
+   f = stbiw__fopen(filename, "wb");
+   if (!f) { STBIW_FREE(png); return 0; }
+   fwrite(png, 1, len, f);
+   fclose(f);
+   STBIW_FREE(png);
+   return 1;
+}
+#endif
+
+STBIWDEF int stbi_write_png_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int stride_bytes)
+{
+   int len;
+   unsigned char *png = stbi_write_png_to_mem((const unsigned char *) data, stride_bytes, x, y, comp, &len);
+   if (png == NULL) return 0;
+   func(context, png, len);
+   STBIW_FREE(png);
+   return 1;
+}
+
+
+/* ***************************************************************************
+ *
+ * JPEG writer
+ *
+ * This is based on Jon Olick's jo_jpeg.cpp:
+ * public domain Simple, Minimalistic JPEG writer - http://www.jonolick.com/code.html
+ */
+
+static const unsigned char stbiw__jpg_ZigZag[] = { 0,1,5,6,14,15,27,28,2,4,7,13,16,26,29,42,3,8,12,17,25,30,41,43,9,11,18,
+      24,31,40,44,53,10,19,23,32,39,45,52,54,20,22,33,38,46,51,55,60,21,34,37,47,50,56,59,61,35,36,48,49,57,58,62,63 };
+
+static void stbiw__jpg_writeBits(stbi__write_context *s, int *bitBufP, int *bitCntP, const unsigned short *bs) {
+   int bitBuf = *bitBufP, bitCnt = *bitCntP;
+   bitCnt += bs[1];
+   bitBuf |= bs[0] << (24 - bitCnt);
+   while(bitCnt >= 8) {
+      unsigned char c = (bitBuf >> 16) & 255;
+      stbiw__putc(s, c);
+      if(c == 255) {
+         stbiw__putc(s, 0);
+      }
+      bitBuf <<= 8;
+      bitCnt -= 8;
+   }
+   *bitBufP = bitBuf;
+   *bitCntP = bitCnt;
+}
+
+static void stbiw__jpg_DCT(float *d0p, float *d1p, float *d2p, float *d3p, float *d4p, float *d5p, float *d6p, float *d7p) {
+   float d0 = *d0p, d1 = *d1p, d2 = *d2p, d3 = *d3p, d4 = *d4p, d5 = *d5p, d6 = *d6p, d7 = *d7p;
+   float z1, z2, z3, z4, z5, z11, z13;
+
+   float tmp0 = d0 + d7;
+   float tmp7 = d0 - d7;
+   float tmp1 = d1 + d6;
+   float tmp6 = d1 - d6;
+   float tmp2 = d2 + d5;
+   float tmp5 = d2 - d5;
+   float tmp3 = d3 + d4;
+   float tmp4 = d3 - d4;
+
+   // Even part
+   float tmp10 = tmp0 + tmp3;   // phase 2
+   float tmp13 = tmp0 - tmp3;
+   float tmp11 = tmp1 + tmp2;
+   float tmp12 = tmp1 - tmp2;
+
+   d0 = tmp10 + tmp11;       // phase 3
+   d4 = tmp10 - tmp11;
+
+   z1 = (tmp12 + tmp13) * 0.707106781f; // c4
+   d2 = tmp13 + z1;       // phase 5
+   d6 = tmp13 - z1;
+
+   // Odd part
+   tmp10 = tmp4 + tmp5;       // phase 2
+   tmp11 = tmp5 + tmp6;
+   tmp12 = tmp6 + tmp7;
+
+   // The rotator is modified from fig 4-8 to avoid extra negations.
+   z5 = (tmp10 - tmp12) * 0.382683433f; // c6
+   z2 = tmp10 * 0.541196100f + z5; // c2-c6
+   z4 = tmp12 * 1.306562965f + z5; // c2+c6
+   z3 = tmp11 * 0.707106781f; // c4
+
+   z11 = tmp7 + z3;      // phase 5
+   z13 = tmp7 - z3;
+
+   *d5p = z13 + z2;         // phase 6
+   *d3p = z13 - z2;
+   *d1p = z11 + z4;
+   *d7p = z11 - z4;
+
+   *d0p = d0;  *d2p = d2;  *d4p = d4;  *d6p = d6;
+}
+
+static void stbiw__jpg_calcBits(int val, unsigned short bits[2]) {
+   int tmp1 = val < 0 ? -val : val;
+   val = val < 0 ? val-1 : val;
+   bits[1] = 1;
+   while(tmp1 >>= 1) {
+      ++bits[1];
+   }
+   bits[0] = val & ((1<<bits[1])-1);
+}
+
+static int stbiw__jpg_processDU(stbi__write_context *s, int *bitBuf, int *bitCnt, float *CDU, float *fdtbl, int DC, const unsigned short HTDC[256][2], const unsigned short HTAC[256][2]) {
+   const unsigned short EOB[2] = { HTAC[0x00][0], HTAC[0x00][1] };
+   const unsigned short M16zeroes[2] = { HTAC[0xF0][0], HTAC[0xF0][1] };
+   int dataOff, i, diff, end0pos;
+   int DU[64];
+
+   // DCT rows
+   for(dataOff=0; dataOff<64; dataOff+=8) {
+      stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff+1], &CDU[dataOff+2], &CDU[dataOff+3], &CDU[dataOff+4], &CDU[dataOff+5], &CDU[dataOff+6], &CDU[dataOff+7]);
+   }
+   // DCT columns
+   for(dataOff=0; dataOff<8; ++dataOff) {
+      stbiw__jpg_DCT(&CDU[dataOff], &CDU[dataOff+8], &CDU[dataOff+16], &CDU[dataOff+24], &CDU[dataOff+32], &CDU[dataOff+40], &CDU[dataOff+48], &CDU[dataOff+56]);
+   }
+   // Quantize/descale/zigzag the coefficients
+   for(i=0; i<64; ++i) {
+      float v = CDU[i]*fdtbl[i];
+      // DU[stbiw__jpg_ZigZag[i]] = (int)(v < 0 ? ceilf(v - 0.5f) : floorf(v + 0.5f));
+      // ceilf() and floorf() are C99, not C89, but I /think/ they're not needed here anyway?
+      DU[stbiw__jpg_ZigZag[i]] = (int)(v < 0 ? v - 0.5f : v + 0.5f);
+   }
+
+   // Encode DC
+   diff = DU[0] - DC;
+   if (diff == 0) {
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[0]);
+   } else {
+      unsigned short bits[2];
+      stbiw__jpg_calcBits(diff, bits);
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTDC[bits[1]]);
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits);
+   }
+   // Encode ACs
+   end0pos = 63;
+   for(; (end0pos>0)&&(DU[end0pos]==0); --end0pos) {
+   }
+   // end0pos = first element in reverse order !=0
+   if(end0pos == 0) {
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB);
+      return DU[0];
+   }
+   for(i = 1; i <= end0pos; ++i) {
+      int startpos = i;
+      int nrzeroes;
+      unsigned short bits[2];
+      for (; DU[i]==0 && i<=end0pos; ++i) {
+      }
+      nrzeroes = i-startpos;
+      if ( nrzeroes >= 16 ) {
+         int lng = nrzeroes>>4;
+         int nrmarker;
+         for (nrmarker=1; nrmarker <= lng; ++nrmarker)
+            stbiw__jpg_writeBits(s, bitBuf, bitCnt, M16zeroes);
+         nrzeroes &= 15;
+      }
+      stbiw__jpg_calcBits(DU[i], bits);
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, HTAC[(nrzeroes<<4)+bits[1]]);
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, bits);
+   }
+   if(end0pos != 63) {
+      stbiw__jpg_writeBits(s, bitBuf, bitCnt, EOB);
+   }
+   return DU[0];
+}
+
+static int stbi_write_jpg_core(stbi__write_context *s, int width, int height, int comp, const void* data, int quality) {
+   // Constants that don't pollute global namespace
+   static const unsigned char std_dc_luminance_nrcodes[] = {0,0,1,5,1,1,1,1,1,1,0,0,0,0,0,0,0};
+   static const unsigned char std_dc_luminance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11};
+   static const unsigned char std_ac_luminance_nrcodes[] = {0,0,2,1,3,3,2,4,3,5,5,4,4,0,0,1,0x7d};
+   static const unsigned char std_ac_luminance_values[] = {
+      0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,0x21,0x31,0x41,0x06,0x13,0x51,0x61,0x07,0x22,0x71,0x14,0x32,0x81,0x91,0xa1,0x08,
+      0x23,0x42,0xb1,0xc1,0x15,0x52,0xd1,0xf0,0x24,0x33,0x62,0x72,0x82,0x09,0x0a,0x16,0x17,0x18,0x19,0x1a,0x25,0x26,0x27,0x28,
+      0x29,0x2a,0x34,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,0x59,
+      0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x83,0x84,0x85,0x86,0x87,0x88,0x89,
+      0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,0xb5,0xb6,
+      0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,0xe1,0xe2,
+      0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa
+   };
+   static const unsigned char std_dc_chrominance_nrcodes[] = {0,0,3,1,1,1,1,1,1,1,1,1,0,0,0,0,0};
+   static const unsigned char std_dc_chrominance_values[] = {0,1,2,3,4,5,6,7,8,9,10,11};
+   static const unsigned char std_ac_chrominance_nrcodes[] = {0,0,2,1,2,4,4,3,4,7,5,4,4,0,1,2,0x77};
+   static const unsigned char std_ac_chrominance_values[] = {
+      0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,0x31,0x06,0x12,0x41,0x51,0x07,0x61,0x71,0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91,
+      0xa1,0xb1,0xc1,0x09,0x23,0x33,0x52,0xf0,0x15,0x62,0x72,0xd1,0x0a,0x16,0x24,0x34,0xe1,0x25,0xf1,0x17,0x18,0x19,0x1a,0x26,
+      0x27,0x28,0x29,0x2a,0x35,0x36,0x37,0x38,0x39,0x3a,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4a,0x53,0x54,0x55,0x56,0x57,0x58,
+      0x59,0x5a,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6a,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7a,0x82,0x83,0x84,0x85,0x86,0x87,
+      0x88,0x89,0x8a,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9a,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7,0xa8,0xa9,0xaa,0xb2,0xb3,0xb4,
+      0xb5,0xb6,0xb7,0xb8,0xb9,0xba,0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,0xc8,0xc9,0xca,0xd2,0xd3,0xd4,0xd5,0xd6,0xd7,0xd8,0xd9,0xda,
+      0xe2,0xe3,0xe4,0xe5,0xe6,0xe7,0xe8,0xe9,0xea,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa
+   };
+   // Huffman tables
+   static const unsigned short YDC_HT[256][2] = { {0,2},{2,3},{3,3},{4,3},{5,3},{6,3},{14,4},{30,5},{62,6},{126,7},{254,8},{510,9}};
+   static const unsigned short UVDC_HT[256][2] = { {0,2},{1,2},{2,2},{6,3},{14,4},{30,5},{62,6},{126,7},{254,8},{510,9},{1022,10},{2046,11}};
+   static const unsigned short YAC_HT[256][2] = {
+      {10,4},{0,2},{1,2},{4,3},{11,4},{26,5},{120,7},{248,8},{1014,10},{65410,16},{65411,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {12,4},{27,5},{121,7},{502,9},{2038,11},{65412,16},{65413,16},{65414,16},{65415,16},{65416,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {28,5},{249,8},{1015,10},{4084,12},{65417,16},{65418,16},{65419,16},{65420,16},{65421,16},{65422,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {58,6},{503,9},{4085,12},{65423,16},{65424,16},{65425,16},{65426,16},{65427,16},{65428,16},{65429,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {59,6},{1016,10},{65430,16},{65431,16},{65432,16},{65433,16},{65434,16},{65435,16},{65436,16},{65437,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {122,7},{2039,11},{65438,16},{65439,16},{65440,16},{65441,16},{65442,16},{65443,16},{65444,16},{65445,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {123,7},{4086,12},{65446,16},{65447,16},{65448,16},{65449,16},{65450,16},{65451,16},{65452,16},{65453,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {250,8},{4087,12},{65454,16},{65455,16},{65456,16},{65457,16},{65458,16},{65459,16},{65460,16},{65461,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {504,9},{32704,15},{65462,16},{65463,16},{65464,16},{65465,16},{65466,16},{65467,16},{65468,16},{65469,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {505,9},{65470,16},{65471,16},{65472,16},{65473,16},{65474,16},{65475,16},{65476,16},{65477,16},{65478,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {506,9},{65479,16},{65480,16},{65481,16},{65482,16},{65483,16},{65484,16},{65485,16},{65486,16},{65487,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {1017,10},{65488,16},{65489,16},{65490,16},{65491,16},{65492,16},{65493,16},{65494,16},{65495,16},{65496,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {1018,10},{65497,16},{65498,16},{65499,16},{65500,16},{65501,16},{65502,16},{65503,16},{65504,16},{65505,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {2040,11},{65506,16},{65507,16},{65508,16},{65509,16},{65510,16},{65511,16},{65512,16},{65513,16},{65514,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {65515,16},{65516,16},{65517,16},{65518,16},{65519,16},{65520,16},{65521,16},{65522,16},{65523,16},{65524,16},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {2041,11},{65525,16},{65526,16},{65527,16},{65528,16},{65529,16},{65530,16},{65531,16},{65532,16},{65533,16},{65534,16},{0,0},{0,0},{0,0},{0,0},{0,0}
+   };
+   static const unsigned short UVAC_HT[256][2] = {
+      {0,2},{1,2},{4,3},{10,4},{24,5},{25,5},{56,6},{120,7},{500,9},{1014,10},{4084,12},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {11,4},{57,6},{246,8},{501,9},{2038,11},{4085,12},{65416,16},{65417,16},{65418,16},{65419,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {26,5},{247,8},{1015,10},{4086,12},{32706,15},{65420,16},{65421,16},{65422,16},{65423,16},{65424,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {27,5},{248,8},{1016,10},{4087,12},{65425,16},{65426,16},{65427,16},{65428,16},{65429,16},{65430,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {58,6},{502,9},{65431,16},{65432,16},{65433,16},{65434,16},{65435,16},{65436,16},{65437,16},{65438,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {59,6},{1017,10},{65439,16},{65440,16},{65441,16},{65442,16},{65443,16},{65444,16},{65445,16},{65446,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {121,7},{2039,11},{65447,16},{65448,16},{65449,16},{65450,16},{65451,16},{65452,16},{65453,16},{65454,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {122,7},{2040,11},{65455,16},{65456,16},{65457,16},{65458,16},{65459,16},{65460,16},{65461,16},{65462,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {249,8},{65463,16},{65464,16},{65465,16},{65466,16},{65467,16},{65468,16},{65469,16},{65470,16},{65471,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {503,9},{65472,16},{65473,16},{65474,16},{65475,16},{65476,16},{65477,16},{65478,16},{65479,16},{65480,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {504,9},{65481,16},{65482,16},{65483,16},{65484,16},{65485,16},{65486,16},{65487,16},{65488,16},{65489,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {505,9},{65490,16},{65491,16},{65492,16},{65493,16},{65494,16},{65495,16},{65496,16},{65497,16},{65498,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {506,9},{65499,16},{65500,16},{65501,16},{65502,16},{65503,16},{65504,16},{65505,16},{65506,16},{65507,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {2041,11},{65508,16},{65509,16},{65510,16},{65511,16},{65512,16},{65513,16},{65514,16},{65515,16},{65516,16},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {16352,14},{65517,16},{65518,16},{65519,16},{65520,16},{65521,16},{65522,16},{65523,16},{65524,16},{65525,16},{0,0},{0,0},{0,0},{0,0},{0,0},
+      {1018,10},{32707,15},{65526,16},{65527,16},{65528,16},{65529,16},{65530,16},{65531,16},{65532,16},{65533,16},{65534,16},{0,0},{0,0},{0,0},{0,0},{0,0}
+   };
+   static const int YQT[] = {16,11,10,16,24,40,51,61,12,12,14,19,26,58,60,55,14,13,16,24,40,57,69,56,14,17,22,29,51,87,80,62,18,22,
+                             37,56,68,109,103,77,24,35,55,64,81,104,113,92,49,64,78,87,103,121,120,101,72,92,95,98,112,100,103,99};
+   static const int UVQT[] = {17,18,24,47,99,99,99,99,18,21,26,66,99,99,99,99,24,26,56,99,99,99,99,99,47,66,99,99,99,99,99,99,
+                              99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99,99};
+   static const float aasf[] = { 1.0f * 2.828427125f, 1.387039845f * 2.828427125f, 1.306562965f * 2.828427125f, 1.175875602f * 2.828427125f, 
+                                 1.0f * 2.828427125f, 0.785694958f * 2.828427125f, 0.541196100f * 2.828427125f, 0.275899379f * 2.828427125f };
+
+   int row, col, i, k;
+   float fdtbl_Y[64], fdtbl_UV[64];
+   unsigned char YTable[64], UVTable[64];
+
+   if(!data || !width || !height || comp > 4 || comp < 1) {
+      return 0;
+   }
+
+   quality = quality ? quality : 90;
+   quality = quality < 1 ? 1 : quality > 100 ? 100 : quality;
+   quality = quality < 50 ? 5000 / quality : 200 - quality * 2;
+
+   for(i = 0; i < 64; ++i) {
+      int uvti, yti = (YQT[i]*quality+50)/100;
+      YTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (yti < 1 ? 1 : yti > 255 ? 255 : yti);
+      uvti = (UVQT[i]*quality+50)/100;
+      UVTable[stbiw__jpg_ZigZag[i]] = (unsigned char) (uvti < 1 ? 1 : uvti > 255 ? 255 : uvti);
+   }
+
+   for(row = 0, k = 0; row < 8; ++row) {
+      for(col = 0; col < 8; ++col, ++k) {
+         fdtbl_Y[k]  = 1 / (YTable [stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]);
+         fdtbl_UV[k] = 1 / (UVTable[stbiw__jpg_ZigZag[k]] * aasf[row] * aasf[col]);
+      }
+   }
+
+   // Write Headers
+   {
+      static const unsigned char head0[] = { 0xFF,0xD8,0xFF,0xE0,0,0x10,'J','F','I','F',0,1,1,0,0,1,0,1,0,0,0xFF,0xDB,0,0x84,0 };
+      static const unsigned char head2[] = { 0xFF,0xDA,0,0xC,3,1,0,2,0x11,3,0x11,0,0x3F,0 };
+      const unsigned char head1[] = { 0xFF,0xC0,0,0x11,8,(unsigned char)(height>>8),STBIW_UCHAR(height),(unsigned char)(width>>8),STBIW_UCHAR(width),
+                                      3,1,0x11,0,2,0x11,1,3,0x11,1,0xFF,0xC4,0x01,0xA2,0 };
+      s->func(s->context, (void*)head0, sizeof(head0));
+      s->func(s->context, (void*)YTable, sizeof(YTable));
+      stbiw__putc(s, 1);
+      s->func(s->context, UVTable, sizeof(UVTable));
+      s->func(s->context, (void*)head1, sizeof(head1));
+      s->func(s->context, (void*)(std_dc_luminance_nrcodes+1), sizeof(std_dc_luminance_nrcodes)-1);
+      s->func(s->context, (void*)std_dc_luminance_values, sizeof(std_dc_luminance_values));
+      stbiw__putc(s, 0x10); // HTYACinfo
+      s->func(s->context, (void*)(std_ac_luminance_nrcodes+1), sizeof(std_ac_luminance_nrcodes)-1);
+      s->func(s->context, (void*)std_ac_luminance_values, sizeof(std_ac_luminance_values));
+      stbiw__putc(s, 1); // HTUDCinfo
+      s->func(s->context, (void*)(std_dc_chrominance_nrcodes+1), sizeof(std_dc_chrominance_nrcodes)-1);
+      s->func(s->context, (void*)std_dc_chrominance_values, sizeof(std_dc_chrominance_values));
+      stbiw__putc(s, 0x11); // HTUACinfo
+      s->func(s->context, (void*)(std_ac_chrominance_nrcodes+1), sizeof(std_ac_chrominance_nrcodes)-1);
+      s->func(s->context, (void*)std_ac_chrominance_values, sizeof(std_ac_chrominance_values));
+      s->func(s->context, (void*)head2, sizeof(head2));
+   }
+
+   // Encode 8x8 macroblocks
+   {
+      static const unsigned short fillBits[] = {0x7F, 7};
+      const unsigned char *imageData = (const unsigned char *)data;
+      int DCY=0, DCU=0, DCV=0;
+      int bitBuf=0, bitCnt=0;
+      // comp == 2 is grey+alpha (alpha is ignored)
+      int ofsG = comp > 2 ? 1 : 0, ofsB = comp > 2 ? 2 : 0;
+      int x, y, pos;
+      for(y = 0; y < height; y += 8) {
+         for(x = 0; x < width; x += 8) {
+            float YDU[64], UDU[64], VDU[64];
+            for(row = y, pos = 0; row < y+8; ++row) {
+               // row >= height => use last input row
+               int clamped_row = (row < height) ? row : height - 1;
+               int base_p = (stbi__flip_vertically_on_write ? (height-1-clamped_row) : clamped_row)*width*comp;
+               for(col = x; col < x+8; ++col, ++pos) {
+                  float r, g, b;
+                  // if col >= width => use pixel from last input column
+                  int p = base_p + ((col < width) ? col : (width-1))*comp;
+
+                  r = imageData[p+0];
+                  g = imageData[p+ofsG];
+                  b = imageData[p+ofsB];
+                  YDU[pos]=+0.29900f*r+0.58700f*g+0.11400f*b-128;
+                  UDU[pos]=-0.16874f*r-0.33126f*g+0.50000f*b;
+                  VDU[pos]=+0.50000f*r-0.41869f*g-0.08131f*b;
+               }
+            }
+
+            DCY = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, YDU, fdtbl_Y, DCY, YDC_HT, YAC_HT);
+            DCU = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, UDU, fdtbl_UV, DCU, UVDC_HT, UVAC_HT);
+            DCV = stbiw__jpg_processDU(s, &bitBuf, &bitCnt, VDU, fdtbl_UV, DCV, UVDC_HT, UVAC_HT);
+         }
+      }
+
+      // Do the bit alignment of the EOI marker
+      stbiw__jpg_writeBits(s, &bitBuf, &bitCnt, fillBits);
+   }
+
+   // EOI
+   stbiw__putc(s, 0xFF);
+   stbiw__putc(s, 0xD9);
+
+   return 1;
+}
+
+STBIWDEF int stbi_write_jpg_to_func(stbi_write_func *func, void *context, int x, int y, int comp, const void *data, int quality)
+{
+   stbi__write_context s;
+   stbi__start_write_callbacks(&s, func, context);
+   return stbi_write_jpg_core(&s, x, y, comp, (void *) data, quality);
+}
+
+
+#ifndef STBI_WRITE_NO_STDIO
+STBIWDEF int stbi_write_jpg(char const *filename, int x, int y, int comp, const void *data, int quality)
+{
+   stbi__write_context s;
+   if (stbi__start_write_file(&s,filename)) {
+      int r = stbi_write_jpg_core(&s, x, y, comp, data, quality);
+      stbi__end_write_file(&s);
+      return r;
+   } else
+      return 0;
+}
+#endif
+
+#endif // STB_IMAGE_WRITE_IMPLEMENTATION
+
+/* Revision history
+      1.10  (2019-02-07)
+             support utf8 filenames in Windows; fix warnings and platform ifdefs 
+      1.09  (2018-02-11)
+             fix typo in zlib quality API, improve STB_I_W_STATIC in C++
+      1.08  (2018-01-29)
+             add stbi__flip_vertically_on_write, external zlib, zlib quality, choose PNG filter
+      1.07  (2017-07-24)
+             doc fix
+      1.06 (2017-07-23)
+             writing JPEG (using Jon Olick's code)
+      1.05   ???
+      1.04 (2017-03-03)
+             monochrome BMP expansion
+      1.03   ???
+      1.02 (2016-04-02)
+             avoid allocating large structures on the stack
+      1.01 (2016-01-16)
+             STBIW_REALLOC_SIZED: support allocators with no realloc support
+             avoid race-condition in crc initialization
+             minor compile issues
+      1.00 (2015-09-14)
+             installable file IO function
+      0.99 (2015-09-13)
+             warning fixes; TGA rle support
+      0.98 (2015-04-08)
+             added STBIW_MALLOC, STBIW_ASSERT etc
+      0.97 (2015-01-18)
+             fixed HDR asserts, rewrote HDR rle logic
+      0.96 (2015-01-17)
+             add HDR output
+             fix monochrome BMP
+      0.95 (2014-08-17)
+		       add monochrome TGA output
+      0.94 (2014-05-31)
+             rename private functions to avoid conflicts with stb_image.h
+      0.93 (2014-05-27)
+             warning fixes
+      0.92 (2010-08-01)
+             casts to unsigned char to fix warnings
+      0.91 (2010-07-17)
+             first public release
+      0.90   first internal release
+*/
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of 
+this software and associated documentation files (the "Software"), to deal in 
+the Software without restriction, including without limitation the rights to 
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
+of the Software, and to permit persons to whom the Software is furnished to do 
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all 
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 
+software, either in source code form or as a compiled binary, for any purpose, 
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this 
+software dedicate any and all copyright interest in the software to the public 
+domain. We make this dedication for the benefit of the public at large and to 
+the detriment of our heirs and successors. We intend this dedication to be an 
+overt act of relinquishment in perpetuity of all present and future rights to 
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/
diff --git a/engine/inc/gltf/tiny_gltf.h b/engine/inc/gltf/tiny_gltf.h
new file mode 100644
index 00000000..88e10931
--- /dev/null
+++ b/engine/inc/gltf/tiny_gltf.h
@@ -0,0 +1,7639 @@
+//
+// Header-only tiny glTF 2.0 loader and serializer.
+//
+//
+// The MIT License (MIT)
+//
+// Copyright (c) 2015 - 2020 Syoyo Fujita, Aurélien Chatelain and many
+// contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+// Version:
+//  - v2.4.2 Decode percent-encoded URI.
+//  - v2.4.1 Fix some glTF object class does not have `extensions` and/or
+//  `extras` property.
+//  - v2.4.0 Experimental RapidJSON and C++14 support(Thanks to @jrkoone).
+//  - v2.3.1 Set default value of minFilter and magFilter in Sampler to -1.
+//  - v2.3.0 Modified Material representation according to glTF 2.0 schema
+//           (and introduced TextureInfo class)
+//           Change the behavior of `Value::IsNumber`. It return true either the
+//           value is int or real.
+//  - v2.2.0 Add loading 16bit PNG support. Add Sparse accessor support(Thanks
+//  to @Ybalrid)
+//  - v2.1.0 Add draco compression.
+//  - v2.0.1 Add comparsion feature(Thanks to @Selmar).
+//  - v2.0.0 glTF 2.0!.
+//
+// Tiny glTF loader is using following third party libraries:
+//
+//  - jsonhpp: C++ JSON library.
+//  - base64: base64 decode/encode library.
+//  - stb_image: Image loading library.
+//
+#ifndef TINY_GLTF_H_
+#define TINY_GLTF_H_
+
+#include <array>
+#include <cassert>
+#include <cmath>  // std::fabs
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <limits>
+#include <map>
+#include <string>
+#include <vector>
+
+#ifndef TINYGLTF_USE_CPP14
+#include <functional>
+#endif
+
+#ifdef __ANDROID__
+#ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
+#include <android/asset_manager.h>
+#endif
+#endif
+
+#ifdef __GNUC__
+#if (__GNUC__ < 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ <= 8))
+#define TINYGLTF_NOEXCEPT
+#else
+#define TINYGLTF_NOEXCEPT noexcept
+#endif
+#else
+#define TINYGLTF_NOEXCEPT noexcept
+#endif
+
+#define DEFAULT_METHODS(x)             \
+  ~x() = default;                      \
+  x(const x &) = default;              \
+  x(x &&) TINYGLTF_NOEXCEPT = default; \
+  x &operator=(const x &) = default;   \
+  x &operator=(x &&) TINYGLTF_NOEXCEPT = default;
+
+namespace tinygltf {
+
+#define TINYGLTF_MODE_POINTS (0)
+#define TINYGLTF_MODE_LINE (1)
+#define TINYGLTF_MODE_LINE_LOOP (2)
+#define TINYGLTF_MODE_LINE_STRIP (3)
+#define TINYGLTF_MODE_TRIANGLES (4)
+#define TINYGLTF_MODE_TRIANGLE_STRIP (5)
+#define TINYGLTF_MODE_TRIANGLE_FAN (6)
+
+#define TINYGLTF_COMPONENT_TYPE_BYTE (5120)
+#define TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE (5121)
+#define TINYGLTF_COMPONENT_TYPE_SHORT (5122)
+#define TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT (5123)
+#define TINYGLTF_COMPONENT_TYPE_INT (5124)
+#define TINYGLTF_COMPONENT_TYPE_UNSIGNED_INT (5125)
+#define TINYGLTF_COMPONENT_TYPE_FLOAT (5126)
+#define TINYGLTF_COMPONENT_TYPE_DOUBLE (5130)
+
+#define TINYGLTF_TEXTURE_FILTER_NEAREST (9728)
+#define TINYGLTF_TEXTURE_FILTER_LINEAR (9729)
+#define TINYGLTF_TEXTURE_FILTER_NEAREST_MIPMAP_NEAREST (9984)
+#define TINYGLTF_TEXTURE_FILTER_LINEAR_MIPMAP_NEAREST (9985)
+#define TINYGLTF_TEXTURE_FILTER_NEAREST_MIPMAP_LINEAR (9986)
+#define TINYGLTF_TEXTURE_FILTER_LINEAR_MIPMAP_LINEAR (9987)
+
+#define TINYGLTF_TEXTURE_WRAP_REPEAT (10497)
+#define TINYGLTF_TEXTURE_WRAP_CLAMP_TO_EDGE (33071)
+#define TINYGLTF_TEXTURE_WRAP_MIRRORED_REPEAT (33648)
+
+// Redeclarations of the above for technique.parameters.
+#define TINYGLTF_PARAMETER_TYPE_BYTE (5120)
+#define TINYGLTF_PARAMETER_TYPE_UNSIGNED_BYTE (5121)
+#define TINYGLTF_PARAMETER_TYPE_SHORT (5122)
+#define TINYGLTF_PARAMETER_TYPE_UNSIGNED_SHORT (5123)
+#define TINYGLTF_PARAMETER_TYPE_INT (5124)
+#define TINYGLTF_PARAMETER_TYPE_UNSIGNED_INT (5125)
+#define TINYGLTF_PARAMETER_TYPE_FLOAT (5126)
+
+#define TINYGLTF_PARAMETER_TYPE_FLOAT_VEC2 (35664)
+#define TINYGLTF_PARAMETER_TYPE_FLOAT_VEC3 (35665)
+#define TINYGLTF_PARAMETER_TYPE_FLOAT_VEC4 (35666)
+
+#define TINYGLTF_PARAMETER_TYPE_INT_VEC2 (35667)
+#define TINYGLTF_PARAMETER_TYPE_INT_VEC3 (35668)
+#define TINYGLTF_PARAMETER_TYPE_INT_VEC4 (35669)
+
+#define TINYGLTF_PARAMETER_TYPE_BOOL (35670)
+#define TINYGLTF_PARAMETER_TYPE_BOOL_VEC2 (35671)
+#define TINYGLTF_PARAMETER_TYPE_BOOL_VEC3 (35672)
+#define TINYGLTF_PARAMETER_TYPE_BOOL_VEC4 (35673)
+
+#define TINYGLTF_PARAMETER_TYPE_FLOAT_MAT2 (35674)
+#define TINYGLTF_PARAMETER_TYPE_FLOAT_MAT3 (35675)
+#define TINYGLTF_PARAMETER_TYPE_FLOAT_MAT4 (35676)
+
+#define TINYGLTF_PARAMETER_TYPE_SAMPLER_2D (35678)
+
+// End parameter types
+
+#define TINYGLTF_TYPE_VEC2 (2)
+#define TINYGLTF_TYPE_VEC3 (3)
+#define TINYGLTF_TYPE_VEC4 (4)
+#define TINYGLTF_TYPE_MAT2 (32 + 2)
+#define TINYGLTF_TYPE_MAT3 (32 + 3)
+#define TINYGLTF_TYPE_MAT4 (32 + 4)
+#define TINYGLTF_TYPE_SCALAR (64 + 1)
+#define TINYGLTF_TYPE_VECTOR (64 + 4)
+#define TINYGLTF_TYPE_MATRIX (64 + 16)
+
+#define TINYGLTF_IMAGE_FORMAT_JPEG (0)
+#define TINYGLTF_IMAGE_FORMAT_PNG (1)
+#define TINYGLTF_IMAGE_FORMAT_BMP (2)
+#define TINYGLTF_IMAGE_FORMAT_GIF (3)
+
+#define TINYGLTF_TEXTURE_FORMAT_ALPHA (6406)
+#define TINYGLTF_TEXTURE_FORMAT_RGB (6407)
+#define TINYGLTF_TEXTURE_FORMAT_RGBA (6408)
+#define TINYGLTF_TEXTURE_FORMAT_LUMINANCE (6409)
+#define TINYGLTF_TEXTURE_FORMAT_LUMINANCE_ALPHA (6410)
+
+#define TINYGLTF_TEXTURE_TARGET_TEXTURE2D (3553)
+#define TINYGLTF_TEXTURE_TYPE_UNSIGNED_BYTE (5121)
+
+#define TINYGLTF_TARGET_ARRAY_BUFFER (34962)
+#define TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER (34963)
+
+#define TINYGLTF_SHADER_TYPE_VERTEX_SHADER (35633)
+#define TINYGLTF_SHADER_TYPE_FRAGMENT_SHADER (35632)
+
+#define TINYGLTF_DOUBLE_EPS (1.e-12)
+#define TINYGLTF_DOUBLE_EQUAL(a, b) (std::fabs((b) - (a)) < TINYGLTF_DOUBLE_EPS)
+
+#ifdef __ANDROID__
+#ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
+AAssetManager *asset_manager = nullptr;
+#endif
+#endif
+
+typedef enum {
+  NULL_TYPE = 0,
+  REAL_TYPE = 1,
+  INT_TYPE = 2,
+  BOOL_TYPE = 3,
+  STRING_TYPE = 4,
+  ARRAY_TYPE = 5,
+  BINARY_TYPE = 6,
+  OBJECT_TYPE = 7
+} Type;
+
+static inline int32_t GetComponentSizeInBytes(uint32_t componentType) {
+  if (componentType == TINYGLTF_COMPONENT_TYPE_BYTE) {
+    return 1;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE) {
+    return 1;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_SHORT) {
+    return 2;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT) {
+    return 2;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_INT) {
+    return 4;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_UNSIGNED_INT) {
+    return 4;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_FLOAT) {
+    return 4;
+  } else if (componentType == TINYGLTF_COMPONENT_TYPE_DOUBLE) {
+    return 8;
+  } else {
+    // Unknown componenty type
+    return -1;
+  }
+}
+
+static inline int32_t GetNumComponentsInType(uint32_t ty) {
+  if (ty == TINYGLTF_TYPE_SCALAR) {
+    return 1;
+  } else if (ty == TINYGLTF_TYPE_VEC2) {
+    return 2;
+  } else if (ty == TINYGLTF_TYPE_VEC3) {
+    return 3;
+  } else if (ty == TINYGLTF_TYPE_VEC4) {
+    return 4;
+  } else if (ty == TINYGLTF_TYPE_MAT2) {
+    return 4;
+  } else if (ty == TINYGLTF_TYPE_MAT3) {
+    return 9;
+  } else if (ty == TINYGLTF_TYPE_MAT4) {
+    return 16;
+  } else {
+    // Unknown componenty type
+    return -1;
+  }
+}
+
+// TODO(syoyo): Move these functions to TinyGLTF class
+bool IsDataURI(const std::string &in);
+bool DecodeDataURI(std::vector<unsigned char> *out, std::string &mime_type,
+                   const std::string &in, size_t reqBytes, bool checkSize);
+
+#ifdef __clang__
+#pragma clang diagnostic push
+// Suppress warning for : static Value null_value
+// https://stackoverflow.com/questions/15708411/how-to-deal-with-global-constructor-warning-in-clang
+#pragma clang diagnostic ignored "-Wexit-time-destructors"
+#pragma clang diagnostic ignored "-Wpadded"
+#endif
+
+// Simple class to represent JSON object
+class Value {
+ public:
+  typedef std::vector<Value> Array;
+  typedef std::map<std::string, Value> Object;
+
+  Value()
+      : type_(NULL_TYPE),
+        int_value_(0),
+        real_value_(0.0),
+        boolean_value_(false) {}
+
+  explicit Value(bool b) : type_(BOOL_TYPE) { boolean_value_ = b; }
+  explicit Value(int i) : type_(INT_TYPE) {
+    int_value_ = i;
+    real_value_ = i;
+  }
+  explicit Value(double n) : type_(REAL_TYPE) { real_value_ = n; }
+  explicit Value(const std::string &s) : type_(STRING_TYPE) {
+    string_value_ = s;
+  }
+  explicit Value(std::string &&s)
+      : type_(STRING_TYPE), string_value_(std::move(s)) {}
+  explicit Value(const unsigned char *p, size_t n) : type_(BINARY_TYPE) {
+    binary_value_.resize(n);
+    memcpy(binary_value_.data(), p, n);
+  }
+  explicit Value(std::vector<unsigned char> &&v) noexcept
+      : type_(BINARY_TYPE),
+        binary_value_(std::move(v)) {}
+  explicit Value(const Array &a) : type_(ARRAY_TYPE) { array_value_ = a; }
+  explicit Value(Array &&a) noexcept : type_(ARRAY_TYPE),
+                                       array_value_(std::move(a)) {}
+
+  explicit Value(const Object &o) : type_(OBJECT_TYPE) { object_value_ = o; }
+  explicit Value(Object &&o) noexcept : type_(OBJECT_TYPE),
+                                        object_value_(std::move(o)) {}
+
+  DEFAULT_METHODS(Value)
+
+  char Type() const { return static_cast<const char>(type_); }
+
+  bool IsBool() const { return (type_ == BOOL_TYPE); }
+
+  bool IsInt() const { return (type_ == INT_TYPE); }
+
+  bool IsNumber() const { return (type_ == REAL_TYPE) || (type_ == INT_TYPE); }
+
+  bool IsReal() const { return (type_ == REAL_TYPE); }
+
+  bool IsString() const { return (type_ == STRING_TYPE); }
+
+  bool IsBinary() const { return (type_ == BINARY_TYPE); }
+
+  bool IsArray() const { return (type_ == ARRAY_TYPE); }
+
+  bool IsObject() const { return (type_ == OBJECT_TYPE); }
+
+  // Use this function if you want to have number value as double.
+  double GetNumberAsDouble() const {
+    if (type_ == INT_TYPE) {
+      return double(int_value_);
+    } else {
+      return real_value_;
+    }
+  }
+
+  // Use this function if you want to have number value as int.
+  // TODO(syoyo): Support int value larger than 32 bits
+  int GetNumberAsInt() const {
+    if (type_ == REAL_TYPE) {
+      return int(real_value_);
+    } else {
+      return int_value_;
+    }
+  }
+
+  // Accessor
+  template <typename T>
+  const T &Get() const;
+  template <typename T>
+  T &Get();
+
+  // Lookup value from an array
+  const Value &Get(int idx) const {
+    static Value null_value;
+    assert(IsArray());
+    assert(idx >= 0);
+    return (static_cast<size_t>(idx) < array_value_.size())
+               ? array_value_[static_cast<size_t>(idx)]
+               : null_value;
+  }
+
+  // Lookup value from a key-value pair
+  const Value &Get(const std::string &key) const {
+    static Value null_value;
+    assert(IsObject());
+    Object::const_iterator it = object_value_.find(key);
+    return (it != object_value_.end()) ? it->second : null_value;
+  }
+
+  size_t ArrayLen() const {
+    if (!IsArray()) return 0;
+    return array_value_.size();
+  }
+
+  // Valid only for object type.
+  bool Has(const std::string &key) const {
+    if (!IsObject()) return false;
+    Object::const_iterator it = object_value_.find(key);
+    return (it != object_value_.end()) ? true : false;
+  }
+
+  // List keys
+  std::vector<std::string> Keys() const {
+    std::vector<std::string> keys;
+    if (!IsObject()) return keys;  // empty
+
+    for (Object::const_iterator it = object_value_.begin();
+         it != object_value_.end(); ++it) {
+      keys.push_back(it->first);
+    }
+
+    return keys;
+  }
+
+  size_t Size() const { return (IsArray() ? ArrayLen() : Keys().size()); }
+
+  bool operator==(const tinygltf::Value &other) const;
+
+ protected:
+  int type_ = NULL_TYPE;
+
+  int int_value_ = 0;
+  double real_value_ = 0.0;
+  std::string string_value_;
+  std::vector<unsigned char> binary_value_;
+  Array array_value_;
+  Object object_value_;
+  bool boolean_value_ = false;
+};
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#define TINYGLTF_VALUE_GET(ctype, var)            \
+  template <>                                     \
+  inline const ctype &Value::Get<ctype>() const { \
+    return var;                                   \
+  }                                               \
+  template <>                                     \
+  inline ctype &Value::Get<ctype>() {             \
+    return var;                                   \
+  }
+TINYGLTF_VALUE_GET(bool, boolean_value_)
+TINYGLTF_VALUE_GET(double, real_value_)
+TINYGLTF_VALUE_GET(int, int_value_)
+TINYGLTF_VALUE_GET(std::string, string_value_)
+TINYGLTF_VALUE_GET(std::vector<unsigned char>, binary_value_)
+TINYGLTF_VALUE_GET(Value::Array, array_value_)
+TINYGLTF_VALUE_GET(Value::Object, object_value_)
+#undef TINYGLTF_VALUE_GET
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc++98-compat"
+#pragma clang diagnostic ignored "-Wpadded"
+#endif
+
+/// Agregate object for representing a color
+using ColorValue = std::array<double, 4>;
+
+// === legacy interface ====
+// TODO(syoyo): Deprecate `Parameter` class.
+struct Parameter {
+  bool bool_value = false;
+  bool has_number_value = false;
+  std::string string_value;
+  std::vector<double> number_array;
+  std::map<std::string, double> json_double_value;
+  double number_value = 0.0;
+
+  // context sensitive methods. depending the type of the Parameter you are
+  // accessing, these are either valid or not
+  // If this parameter represent a texture map in a material, will return the
+  // texture index
+
+  /// Return the index of a texture if this Parameter is a texture map.
+  /// Returned value is only valid if the parameter represent a texture from a
+  /// material
+  int TextureIndex() const {
+    const auto it = json_double_value.find("index");
+    if (it != std::end(json_double_value)) {
+      return int(it->second);
+    }
+    return -1;
+  }
+
+  /// Return the index of a texture coordinate set if this Parameter is a
+  /// texture map. Returned value is only valid if the parameter represent a
+  /// texture from a material
+  int TextureTexCoord() const {
+    const auto it = json_double_value.find("texCoord");
+    if (it != std::end(json_double_value)) {
+      return int(it->second);
+    }
+    // As per the spec, if texCoord is ommited, this parameter is 0
+    return 0;
+  }
+
+  /// Return the scale of a texture if this Parameter is a normal texture map.
+  /// Returned value is only valid if the parameter represent a normal texture
+  /// from a material
+  double TextureScale() const {
+    const auto it = json_double_value.find("scale");
+    if (it != std::end(json_double_value)) {
+      return it->second;
+    }
+    // As per the spec, if scale is ommited, this paramter is 1
+    return 1;
+  }
+
+  /// Return the strength of a texture if this Parameter is a an occlusion map.
+  /// Returned value is only valid if the parameter represent an occlusion map
+  /// from a material
+  double TextureStrength() const {
+    const auto it = json_double_value.find("strength");
+    if (it != std::end(json_double_value)) {
+      return it->second;
+    }
+    // As per the spec, if strenghth is ommited, this parameter is 1
+    return 1;
+  }
+
+  /// Material factor, like the roughness or metalness of a material
+  /// Returned value is only valid if the parameter represent a texture from a
+  /// material
+  double Factor() const { return number_value; }
+
+  /// Return the color of a material
+  /// Returned value is only valid if the parameter represent a texture from a
+  /// material
+  ColorValue ColorFactor() const {
+    return {
+        {// this agregate intialize the std::array object, and uses C++11 RVO.
+         number_array[0], number_array[1], number_array[2],
+         (number_array.size() > 3 ? number_array[3] : 1.0)}};
+  }
+
+  Parameter() = default;
+  DEFAULT_METHODS(Parameter)
+  bool operator==(const Parameter &) const;
+};
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wpadded"
+#endif
+
+typedef std::map<std::string, Parameter> ParameterMap;
+typedef std::map<std::string, Value> ExtensionMap;
+
+struct AnimationChannel {
+  int sampler;              // required
+  int target_node;          // required (index of the node to target)
+  std::string target_path;  // required in ["translation", "rotation", "scale",
+                            // "weights"]
+  Value extras;
+  ExtensionMap extensions;
+  ExtensionMap target_extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+  std::string target_extensions_json_string;
+
+  AnimationChannel() : sampler(-1), target_node(-1) {}
+  DEFAULT_METHODS(AnimationChannel)
+  bool operator==(const AnimationChannel &) const;
+};
+
+struct AnimationSampler {
+  int input;                  // required
+  int output;                 // required
+  std::string interpolation;  // "LINEAR", "STEP","CUBICSPLINE" or user defined
+                              // string. default "LINEAR"
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  AnimationSampler() : input(-1), output(-1), interpolation("LINEAR") {}
+  DEFAULT_METHODS(AnimationSampler)
+  bool operator==(const AnimationSampler &) const;
+};
+
+struct Animation {
+  std::string name;
+  std::vector<AnimationChannel> channels;
+  std::vector<AnimationSampler> samplers;
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Animation() = default;
+  DEFAULT_METHODS(Animation)
+  bool operator==(const Animation &) const;
+};
+
+struct Skin {
+  std::string name;
+  int inverseBindMatrices;  // required here but not in the spec
+  int skeleton;             // The index of the node used as a skeleton root
+  std::vector<int> joints;  // Indices of skeleton nodes
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Skin() {
+    inverseBindMatrices = -1;
+    skeleton = -1;
+  }
+  DEFAULT_METHODS(Skin)
+  bool operator==(const Skin &) const;
+};
+
+struct Sampler {
+  std::string name;
+  // glTF 2.0 spec does not define default value for `minFilter` and
+  // `magFilter`. Set -1 in TinyGLTF(issue #186)
+  int minFilter =
+      -1;  // optional. -1 = no filter defined. ["NEAREST", "LINEAR",
+           // "NEAREST_MIPMAP_LINEAR", "LINEAR_MIPMAP_NEAREST",
+           // "NEAREST_MIPMAP_LINEAR", "LINEAR_MIPMAP_LINEAR"]
+  int magFilter =
+      -1;  // optional. -1 = no filter defined. ["NEAREST", "LINEAR"]
+  int wrapS =
+      TINYGLTF_TEXTURE_WRAP_REPEAT;  // ["CLAMP_TO_EDGE", "MIRRORED_REPEAT",
+                                     // "REPEAT"], default "REPEAT"
+  int wrapT =
+      TINYGLTF_TEXTURE_WRAP_REPEAT;  // ["CLAMP_TO_EDGE", "MIRRORED_REPEAT",
+                                     // "REPEAT"], default "REPEAT"
+  int wrapR = TINYGLTF_TEXTURE_WRAP_REPEAT;  // TinyGLTF extension
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Sampler()
+      : minFilter(-1),
+        magFilter(-1),
+        wrapS(TINYGLTF_TEXTURE_WRAP_REPEAT),
+        wrapT(TINYGLTF_TEXTURE_WRAP_REPEAT),
+        wrapR(TINYGLTF_TEXTURE_WRAP_REPEAT) {}
+  DEFAULT_METHODS(Sampler)
+  bool operator==(const Sampler &) const;
+};
+
+struct Image {
+  std::string name;
+  int width;
+  int height;
+  int component;
+  int bits;        // bit depth per channel. 8(byte), 16 or 32.
+  int pixel_type;  // pixel type(TINYGLTF_COMPONENT_TYPE_***). usually
+                   // UBYTE(bits = 8) or USHORT(bits = 16)
+  std::vector<unsigned char> image;
+  int bufferView;        // (required if no uri)
+  std::string mimeType;  // (required if no uri) ["image/jpeg", "image/png",
+                         // "image/bmp", "image/gif"]
+  std::string uri;       // (required if no mimeType) uri is not decoded(e.g.
+                         // whitespace may be represented as %20)
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  // When this flag is true, data is stored to `image` in as-is format(e.g. jpeg
+  // compressed for "image/jpeg" mime) This feature is good if you use custom
+  // image loader function. (e.g. delayed decoding of images for faster glTF
+  // parsing) Default parser for Image does not provide as-is loading feature at
+  // the moment. (You can manipulate this by providing your own LoadImageData
+  // function)
+  bool as_is;
+
+  Image() : as_is(false) {
+    bufferView = -1;
+    width = -1;
+    height = -1;
+    component = -1;
+    bits = -1;
+    pixel_type = -1;
+  }
+  DEFAULT_METHODS(Image)
+
+  bool operator==(const Image &) const;
+};
+
+struct Texture {
+  std::string name;
+
+  int sampler;
+  int source;
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Texture() : sampler(-1), source(-1) {}
+  DEFAULT_METHODS(Texture)
+
+  bool operator==(const Texture &) const;
+};
+
+struct TextureInfo {
+  int index = -1;  // required.
+  int texCoord;    // The set index of texture's TEXCOORD attribute used for
+                   // texture coordinate mapping.
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  TextureInfo() : index(-1), texCoord(0) {}
+  DEFAULT_METHODS(TextureInfo)
+  bool operator==(const TextureInfo &) const;
+};
+
+struct NormalTextureInfo {
+  int index = -1;  // required
+  int texCoord;    // The set index of texture's TEXCOORD attribute used for
+                   // texture coordinate mapping.
+  double scale;    // scaledNormal = normalize((<sampled normal texture value>
+                   // * 2.0 - 1.0) * vec3(<normal scale>, <normal scale>, 1.0))
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  NormalTextureInfo() : index(-1), texCoord(0), scale(1.0) {}
+  DEFAULT_METHODS(NormalTextureInfo)
+  bool operator==(const NormalTextureInfo &) const;
+};
+
+struct OcclusionTextureInfo {
+  int index = -1;   // required
+  int texCoord;     // The set index of texture's TEXCOORD attribute used for
+                    // texture coordinate mapping.
+  double strength;  // occludedColor = lerp(color, color * <sampled occlusion
+                    // texture value>, <occlusion strength>)
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  OcclusionTextureInfo() : index(-1), texCoord(0), strength(1.0) {}
+  DEFAULT_METHODS(OcclusionTextureInfo)
+  bool operator==(const OcclusionTextureInfo &) const;
+};
+
+// pbrMetallicRoughness class defined in glTF 2.0 spec.
+struct PbrMetallicRoughness {
+  std::vector<double> baseColorFactor;  // len = 4. default [1,1,1,1]
+  TextureInfo baseColorTexture;
+  double metallicFactor;   // default 1
+  double roughnessFactor;  // default 1
+  TextureInfo metallicRoughnessTexture;
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  PbrMetallicRoughness()
+      : baseColorFactor(std::vector<double>{1.0, 1.0, 1.0, 1.0}),
+        metallicFactor(1.0),
+        roughnessFactor(1.0) {}
+  DEFAULT_METHODS(PbrMetallicRoughness)
+  bool operator==(const PbrMetallicRoughness &) const;
+};
+
+// Each extension should be stored in a ParameterMap.
+// members not in the values could be included in the ParameterMap
+// to keep a single material model
+struct Material {
+  std::string name;
+
+  std::vector<double> emissiveFactor;  // length 3. default [0, 0, 0]
+  std::string alphaMode;               // default "OPAQUE"
+  double alphaCutoff;                  // default 0.5
+  bool doubleSided;                    // default false;
+
+  PbrMetallicRoughness pbrMetallicRoughness;
+
+  NormalTextureInfo normalTexture;
+  OcclusionTextureInfo occlusionTexture;
+  TextureInfo emissiveTexture;
+
+  // For backward compatibility
+  // TODO(syoyo): Remove `values` and `additionalValues` in the next release.
+  ParameterMap values;
+  ParameterMap additionalValues;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Material() : alphaMode("OPAQUE"), alphaCutoff(0.5), doubleSided(false) {}
+  DEFAULT_METHODS(Material)
+
+  bool operator==(const Material &) const;
+};
+
+struct BufferView {
+  std::string name;
+  int buffer{-1};        // Required
+  size_t byteOffset{0};  // minimum 0, default 0
+  size_t byteLength{0};  // required, minimum 1. 0 = invalid
+  size_t byteStride{0};  // minimum 4, maximum 252 (multiple of 4), default 0 =
+                         // understood to be tightly packed
+  int target{0};  // ["ARRAY_BUFFER", "ELEMENT_ARRAY_BUFFER"] for vertex indices
+                  // or atttribs. Could be 0 for other data
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  bool dracoDecoded{false};  // Flag indicating this has been draco decoded
+
+  BufferView()
+      : buffer(-1),
+        byteOffset(0),
+        byteLength(0),
+        byteStride(0),
+        target(0),
+        dracoDecoded(false) {}
+  DEFAULT_METHODS(BufferView)
+  bool operator==(const BufferView &) const;
+};
+
+struct Accessor {
+  int bufferView;  // optional in spec but required here since sparse accessor
+                   // are not supported
+  std::string name;
+  size_t byteOffset;
+  bool normalized;    // optional.
+  int componentType;  // (required) One of TINYGLTF_COMPONENT_TYPE_***
+  size_t count;       // required
+  int type;           // (required) One of TINYGLTF_TYPE_***   ..
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  std::vector<double> minValues;  // optional
+  std::vector<double> maxValues;  // optional
+
+  struct {
+    int count;
+    bool isSparse;
+    struct {
+      int byteOffset;
+      int bufferView;
+      int componentType;  // a TINYGLTF_COMPONENT_TYPE_ value
+    } indices;
+    struct {
+      int bufferView;
+      int byteOffset;
+    } values;
+  } sparse;
+
+  ///
+  /// Utility function to compute byteStride for a given bufferView object.
+  /// Returns -1 upon invalid glTF value or parameter configuration.
+  ///
+  int ByteStride(const BufferView &bufferViewObject) const {
+    if (bufferViewObject.byteStride == 0) {
+      // Assume data is tightly packed.
+      int componentSizeInBytes =
+          GetComponentSizeInBytes(static_cast<uint32_t>(componentType));
+      if (componentSizeInBytes <= 0) {
+        return -1;
+      }
+
+      int numComponents = GetNumComponentsInType(static_cast<uint32_t>(type));
+      if (numComponents <= 0) {
+        return -1;
+      }
+
+      return componentSizeInBytes * numComponents;
+    } else {
+      // Check if byteStride is a mulple of the size of the accessor's component
+      // type.
+      int componentSizeInBytes =
+          GetComponentSizeInBytes(static_cast<uint32_t>(componentType));
+      if (componentSizeInBytes <= 0) {
+        return -1;
+      }
+
+      if ((bufferViewObject.byteStride % uint32_t(componentSizeInBytes)) != 0) {
+        return -1;
+      }
+      return static_cast<int>(bufferViewObject.byteStride);
+    }
+
+    // unreachable return 0;
+  }
+
+  Accessor()
+      : bufferView(-1),
+        byteOffset(0),
+        normalized(false),
+        componentType(-1),
+        count(0),
+        type(-1) {
+    sparse.isSparse = false;
+  }
+  DEFAULT_METHODS(Accessor)
+  bool operator==(const tinygltf::Accessor &) const;
+};
+
+struct PerspectiveCamera {
+  double aspectRatio;  // min > 0
+  double yfov;         // required. min > 0
+  double zfar;         // min > 0
+  double znear;        // required. min > 0
+
+  PerspectiveCamera()
+      : aspectRatio(0.0),
+        yfov(0.0),
+        zfar(0.0)  // 0 = use infinite projecton matrix
+        ,
+        znear(0.0) {}
+  DEFAULT_METHODS(PerspectiveCamera)
+  bool operator==(const PerspectiveCamera &) const;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+struct OrthographicCamera {
+  double xmag;   // required. must not be zero.
+  double ymag;   // required. must not be zero.
+  double zfar;   // required. `zfar` must be greater than `znear`.
+  double znear;  // required
+
+  OrthographicCamera() : xmag(0.0), ymag(0.0), zfar(0.0), znear(0.0) {}
+  DEFAULT_METHODS(OrthographicCamera)
+  bool operator==(const OrthographicCamera &) const;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+struct Camera {
+  std::string type;  // required. "perspective" or "orthographic"
+  std::string name;
+
+  PerspectiveCamera perspective;
+  OrthographicCamera orthographic;
+
+  Camera() {}
+  DEFAULT_METHODS(Camera)
+  bool operator==(const Camera &) const;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+struct Primitive {
+  std::map<std::string, int> attributes;  // (required) A dictionary object of
+                                          // integer, where each integer
+                                          // is the index of the accessor
+                                          // containing an attribute.
+  int material;  // The index of the material to apply to this primitive
+                 // when rendering.
+  int indices;   // The index of the accessor that contains the indices.
+  int mode;      // one of TINYGLTF_MODE_***
+  std::vector<std::map<std::string, int> > targets;  // array of morph targets,
+  // where each target is a dict with attribues in ["POSITION, "NORMAL",
+  // "TANGENT"] pointing
+  // to their corresponding accessors
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Primitive() {
+    material = -1;
+    indices = -1;
+    mode = -1;
+  }
+  DEFAULT_METHODS(Primitive)
+  bool operator==(const Primitive &) const;
+};
+
+struct Mesh {
+  std::string name;
+  std::vector<Primitive> primitives;
+  std::vector<double> weights;  // weights to be applied to the Morph Targets
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Mesh() = default;
+  DEFAULT_METHODS(Mesh)
+  bool operator==(const Mesh &) const;
+};
+
+class Node {
+ public:
+  Node() : camera(-1), skin(-1), mesh(-1) {}
+
+  DEFAULT_METHODS(Node)
+
+  bool operator==(const Node &) const;
+
+  int camera;  // the index of the camera referenced by this node
+
+  std::string name;
+  int skin;
+  int mesh;
+  std::vector<int> children;
+  std::vector<double> rotation;     // length must be 0 or 4
+  std::vector<double> scale;        // length must be 0 or 3
+  std::vector<double> translation;  // length must be 0 or 3
+  std::vector<double> matrix;       // length must be 0 or 16
+  std::vector<double> weights;  // The weights of the instantiated Morph Target
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+struct Buffer {
+  std::string name;
+  std::vector<unsigned char> data;
+  std::string
+      uri;  // considered as required here but not in the spec (need to clarify)
+            // uri is not decoded(e.g. whitespace may be represented as %20)
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Buffer() = default;
+  DEFAULT_METHODS(Buffer)
+  bool operator==(const Buffer &) const;
+};
+
+struct Asset {
+  std::string version;  // required
+  std::string generator;
+  std::string minVersion;
+  std::string copyright;
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Asset() = default;
+  DEFAULT_METHODS(Asset)
+  bool operator==(const Asset &) const;
+};
+
+struct Scene {
+  std::string name;
+  std::vector<int> nodes;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+
+  Scene() = default;
+  DEFAULT_METHODS(Scene)
+  bool operator==(const Scene &) const;
+};
+
+struct SpotLight {
+  double innerConeAngle;
+  double outerConeAngle;
+
+  SpotLight() : innerConeAngle(0.0), outerConeAngle(0.7853981634) {}
+  DEFAULT_METHODS(SpotLight)
+  bool operator==(const SpotLight &) const;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+struct Light {
+  std::string name;
+  std::vector<double> color;
+  double intensity{1.0};
+  std::string type;
+  double range{0.0};  // 0.0 = inifinite
+  SpotLight spot;
+
+  Light() : intensity(1.0), range(0.0) {}
+  DEFAULT_METHODS(Light)
+
+  bool operator==(const Light &) const;
+
+  ExtensionMap extensions;
+  Value extras;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+class Model {
+ public:
+  Model() = default;
+  DEFAULT_METHODS(Model)
+
+  bool operator==(const Model &) const;
+
+  std::vector<Accessor> accessors;
+  std::vector<Animation> animations;
+  std::vector<Buffer> buffers;
+  std::vector<BufferView> bufferViews;
+  std::vector<Material> materials;
+  std::vector<Mesh> meshes;
+  std::vector<Node> nodes;
+  std::vector<Texture> textures;
+  std::vector<Image> images;
+  std::vector<Skin> skins;
+  std::vector<Sampler> samplers;
+  std::vector<Camera> cameras;
+  std::vector<Scene> scenes;
+  std::vector<Light> lights;
+
+  int defaultScene = -1;
+  std::vector<std::string> extensionsUsed;
+  std::vector<std::string> extensionsRequired;
+
+  Asset asset;
+
+  Value extras;
+  ExtensionMap extensions;
+
+  // Filled when SetStoreOriginalJSONForExtrasAndExtensions is enabled.
+  std::string extras_json_string;
+  std::string extensions_json_string;
+};
+
+enum SectionCheck {
+  NO_REQUIRE = 0x00,
+  REQUIRE_VERSION = 0x01,
+  REQUIRE_SCENE = 0x02,
+  REQUIRE_SCENES = 0x04,
+  REQUIRE_NODES = 0x08,
+  REQUIRE_ACCESSORS = 0x10,
+  REQUIRE_BUFFERS = 0x20,
+  REQUIRE_BUFFER_VIEWS = 0x40,
+  REQUIRE_ALL = 0x7f
+};
+
+///
+/// LoadImageDataFunction type. Signature for custom image loading callbacks.
+///
+typedef bool (*LoadImageDataFunction)(Image *, const int, std::string *,
+                                      std::string *, int, int,
+                                      const unsigned char *, int, void *);
+
+///
+/// WriteImageDataFunction type. Signature for custom image writing callbacks.
+///
+typedef bool (*WriteImageDataFunction)(const std::string *, const std::string *,
+                                       Image *, bool, void *);
+
+#ifndef TINYGLTF_NO_STB_IMAGE
+// Declaration of default image loader callback
+bool LoadImageData(Image *image, const int image_idx, std::string *err,
+                   std::string *warn, int req_width, int req_height,
+                   const unsigned char *bytes, int size, void *);
+#endif
+
+#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
+// Declaration of default image writer callback
+bool WriteImageData(const std::string *basepath, const std::string *filename,
+                    Image *image, bool embedImages, void *);
+#endif
+
+///
+/// FilExistsFunction type. Signature for custom filesystem callbacks.
+///
+typedef bool (*FileExistsFunction)(const std::string &abs_filename, void *);
+
+///
+/// ExpandFilePathFunction type. Signature for custom filesystem callbacks.
+///
+typedef std::string (*ExpandFilePathFunction)(const std::string &, void *);
+
+///
+/// ReadWholeFileFunction type. Signature for custom filesystem callbacks.
+///
+typedef bool (*ReadWholeFileFunction)(std::vector<unsigned char> *,
+                                      std::string *, const std::string &,
+                                      void *);
+
+///
+/// WriteWholeFileFunction type. Signature for custom filesystem callbacks.
+///
+typedef bool (*WriteWholeFileFunction)(std::string *, const std::string &,
+                                       const std::vector<unsigned char> &,
+                                       void *);
+
+///
+/// A structure containing all required filesystem callbacks and a pointer to
+/// their user data.
+///
+struct FsCallbacks {
+  FileExistsFunction FileExists;
+  ExpandFilePathFunction ExpandFilePath;
+  ReadWholeFileFunction ReadWholeFile;
+  WriteWholeFileFunction WriteWholeFile;
+
+  void *user_data;  // An argument that is passed to all fs callbacks
+};
+
+#ifndef TINYGLTF_NO_FS
+// Declaration of default filesystem callbacks
+
+bool FileExists(const std::string &abs_filename, void *);
+
+///
+/// Expand file path(e.g. `~` to home directory on posix, `%APPDATA%` to
+/// `C:\Users\tinygltf\AppData`)
+///
+/// @param[in] filepath File path string. Assume UTF-8
+/// @param[in] userdata User data. Set to `nullptr` if you don't need it.
+///
+std::string ExpandFilePath(const std::string &filepath, void *userdata);
+
+bool ReadWholeFile(std::vector<unsigned char> *out, std::string *err,
+                   const std::string &filepath, void *);
+
+bool WriteWholeFile(std::string *err, const std::string &filepath,
+                    const std::vector<unsigned char> &contents, void *);
+#endif
+
+///
+/// glTF Parser/Serialier context.
+///
+class TinyGLTF {
+ public:
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc++98-compat"
+#endif
+
+  TinyGLTF() : bin_data_(nullptr), bin_size_(0), is_binary_(false) {}
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+  ~TinyGLTF() {}
+
+  ///
+  /// Loads glTF ASCII asset from a file.
+  /// Set warning message to `warn` for example it fails to load asserts.
+  /// Returns false and set error string to `err` if there's an error.
+  ///
+  bool LoadASCIIFromFile(Model *model, std::string *err, std::string *warn,
+                         const std::string &filename,
+                         unsigned int check_sections = REQUIRE_VERSION);
+
+  ///
+  /// Loads glTF ASCII asset from string(memory).
+  /// `length` = strlen(str);
+  /// Set warning message to `warn` for example it fails to load asserts.
+  /// Returns false and set error string to `err` if there's an error.
+  ///
+  bool LoadASCIIFromString(Model *model, std::string *err, std::string *warn,
+                           const char *str, const unsigned int length,
+                           const std::string &base_dir,
+                           unsigned int check_sections = REQUIRE_VERSION);
+
+  ///
+  /// Loads glTF binary asset from a file.
+  /// Set warning message to `warn` for example it fails to load asserts.
+  /// Returns false and set error string to `err` if there's an error.
+  ///
+  bool LoadBinaryFromFile(Model *model, std::string *err, std::string *warn,
+                          const std::string &filename,
+                          unsigned int check_sections = REQUIRE_VERSION);
+
+  ///
+  /// Loads glTF binary asset from memory.
+  /// `length` = strlen(str);
+  /// Set warning message to `warn` for example it fails to load asserts.
+  /// Returns false and set error string to `err` if there's an error.
+  ///
+  bool LoadBinaryFromMemory(Model *model, std::string *err, std::string *warn,
+                            const unsigned char *bytes,
+                            const unsigned int length,
+                            const std::string &base_dir = "",
+                            unsigned int check_sections = REQUIRE_VERSION);
+
+  ///
+  /// Write glTF to stream, buffers and images will be embeded
+  ///
+  bool WriteGltfSceneToStream(Model *model, std::ostream &stream,
+                              bool prettyPrint, bool writeBinary);
+
+  ///
+  /// Write glTF to file.
+  ///
+  bool WriteGltfSceneToFile(Model *model, const std::string &filename,
+                            bool embedImages, bool embedBuffers,
+                            bool prettyPrint, bool writeBinary);
+
+  ///
+  /// Set callback to use for loading image data
+  ///
+  void SetImageLoader(LoadImageDataFunction LoadImageData, void *user_data);
+
+  ///
+  /// Set callback to use for writing image data
+  ///
+  void SetImageWriter(WriteImageDataFunction WriteImageData, void *user_data);
+
+  ///
+  /// Set callbacks to use for filesystem (fs) access and their user data
+  ///
+  void SetFsCallbacks(FsCallbacks callbacks);
+
+  ///
+  /// Set serializing default values(default = false).
+  /// When true, default values are force serialized to .glTF.
+  /// This may be helpfull if you want to serialize a full description of glTF
+  /// data.
+  ///
+  /// TODO(LTE): Supply parsing option as function arguments to
+  /// `LoadASCIIFromFile()` and others, not by a class method
+  ///
+  void SetSerializeDefaultValues(const bool enabled) {
+    serialize_default_values_ = enabled;
+  }
+
+  bool GetSerializeDefaultValues() const { return serialize_default_values_; }
+
+  ///
+  /// Store original JSON string for `extras` and `extensions`.
+  /// This feature will be useful when the user want to reconstruct custom data
+  /// structure from JSON string.
+  ///
+  void SetStoreOriginalJSONForExtrasAndExtensions(const bool enabled) {
+    store_original_json_for_extras_and_extensions_ = enabled;
+  }
+
+  bool GetStoreOriginalJSONForExtrasAndExtensions() const {
+    return store_original_json_for_extras_and_extensions_;
+  }
+
+ private:
+  ///
+  /// Loads glTF asset from string(memory).
+  /// `length` = strlen(str);
+  /// Set warning message to `warn` for example it fails to load asserts
+  /// Returns false and set error string to `err` if there's an error.
+  ///
+  bool LoadFromString(Model *model, std::string *err, std::string *warn,
+                      const char *str, const unsigned int length,
+                      const std::string &base_dir, unsigned int check_sections);
+
+  const unsigned char *bin_data_ = nullptr;
+  size_t bin_size_ = 0;
+  bool is_binary_ = false;
+
+  bool serialize_default_values_ = false;  ///< Serialize default values?
+
+  bool store_original_json_for_extras_and_extensions_ = false;
+
+  FsCallbacks fs = {
+#ifndef TINYGLTF_NO_FS
+      &tinygltf::FileExists, &tinygltf::ExpandFilePath,
+      &tinygltf::ReadWholeFile, &tinygltf::WriteWholeFile,
+
+      nullptr  // Fs callback user data
+#else
+      nullptr, nullptr, nullptr, nullptr,
+
+      nullptr  // Fs callback user data
+#endif
+  };
+
+  LoadImageDataFunction LoadImageData =
+#ifndef TINYGLTF_NO_STB_IMAGE
+      &tinygltf::LoadImageData;
+#else
+      nullptr;
+#endif
+  void *load_image_user_data_ = reinterpret_cast<void *>(&fs);
+
+  WriteImageDataFunction WriteImageData =
+#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
+      &tinygltf::WriteImageData;
+#else
+      nullptr;
+#endif
+  void *write_image_user_data_ = reinterpret_cast<void *>(&fs);
+};
+
+#ifdef __clang__
+#pragma clang diagnostic pop  // -Wpadded
+#endif
+
+}  // namespace tinygltf
+
+#endif  // TINY_GLTF_H_
+
+#if defined(TINYGLTF_IMPLEMENTATION) || defined(__INTELLISENSE__)
+#include <algorithm>
+//#include <cassert>
+#ifndef TINYGLTF_NO_FS
+#include <cstdio>
+#include <fstream>
+#endif
+#include <sstream>
+
+#ifdef __clang__
+// Disable some warnings for external files.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wfloat-equal"
+#pragma clang diagnostic ignored "-Wexit-time-destructors"
+#pragma clang diagnostic ignored "-Wconversion"
+#pragma clang diagnostic ignored "-Wold-style-cast"
+#pragma clang diagnostic ignored "-Wglobal-constructors"
+#if __has_warning("-Wreserved-id-macro")
+#pragma clang diagnostic ignored "-Wreserved-id-macro"
+#endif
+#pragma clang diagnostic ignored "-Wdisabled-macro-expansion"
+#pragma clang diagnostic ignored "-Wpadded"
+#pragma clang diagnostic ignored "-Wc++98-compat"
+#pragma clang diagnostic ignored "-Wc++98-compat-pedantic"
+#pragma clang diagnostic ignored "-Wdocumentation-unknown-command"
+#pragma clang diagnostic ignored "-Wswitch-enum"
+#pragma clang diagnostic ignored "-Wimplicit-fallthrough"
+#pragma clang diagnostic ignored "-Wweak-vtables"
+#pragma clang diagnostic ignored "-Wcovered-switch-default"
+#if __has_warning("-Wdouble-promotion")
+#pragma clang diagnostic ignored "-Wdouble-promotion"
+#endif
+#if __has_warning("-Wcomma")
+#pragma clang diagnostic ignored "-Wcomma"
+#endif
+#if __has_warning("-Wzero-as-null-pointer-constant")
+#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"
+#endif
+#if __has_warning("-Wcast-qual")
+#pragma clang diagnostic ignored "-Wcast-qual"
+#endif
+#if __has_warning("-Wmissing-variable-declarations")
+#pragma clang diagnostic ignored "-Wmissing-variable-declarations"
+#endif
+#if __has_warning("-Wmissing-prototypes")
+#pragma clang diagnostic ignored "-Wmissing-prototypes"
+#endif
+#if __has_warning("-Wcast-align")
+#pragma clang diagnostic ignored "-Wcast-align"
+#endif
+#if __has_warning("-Wnewline-eof")
+#pragma clang diagnostic ignored "-Wnewline-eof"
+#endif
+#if __has_warning("-Wunused-parameter")
+#pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+#if __has_warning("-Wmismatched-tags")
+#pragma clang diagnostic ignored "-Wmismatched-tags"
+#endif
+#if __has_warning("-Wextra-semi-stmt")
+#pragma clang diagnostic ignored "-Wextra-semi-stmt"
+#endif
+#endif
+
+// Disable GCC warnigs
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wtype-limits"
+#endif  // __GNUC__
+
+#ifndef TINYGLTF_NO_INCLUDE_JSON
+#ifndef TINYGLTF_USE_RAPIDJSON
+#include "json.hpp"
+#else
+#include "document.h"
+#include "prettywriter.h"
+#include "rapidjson.h"
+#include "stringbuffer.h"
+#include "writer.h"
+#endif
+#endif
+
+#ifdef TINYGLTF_ENABLE_DRACO
+#include "draco/compression/decode.h"
+#include "draco/core/decoder_buffer.h"
+#endif
+
+#ifndef TINYGLTF_NO_STB_IMAGE
+#ifndef TINYGLTF_NO_INCLUDE_STB_IMAGE
+#include "stb_image.h"
+#endif
+#endif
+
+#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
+#ifndef TINYGLTF_NO_INCLUDE_STB_IMAGE_WRITE
+#include "stb_image_write.h"
+#endif
+#endif
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif
+
+#ifdef _WIN32
+
+// issue 143.
+// Define NOMINMAX to avoid min/max defines,
+// but undef it after included windows.h
+#ifndef NOMINMAX
+#define TINYGLTF_INTERNAL_NOMINMAX
+#define NOMINMAX
+#endif
+
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#define TINYGLTF_INTERNAL_WIN32_LEAN_AND_MEAN
+#endif
+#include <windows.h>  // include API for expanding a file path
+
+#ifdef TINYGLTF_INTERNAL_WIN32_LEAN_AND_MEAN
+#undef WIN32_LEAN_AND_MEAN
+#endif
+
+#if defined(TINYGLTF_INTERNAL_NOMINMAX)
+#undef NOMINMAX
+#endif
+
+#if defined(__GLIBCXX__)  // mingw
+
+#include <fcntl.h>  // _O_RDONLY
+
+#include <ext/stdio_filebuf.h>  // fstream (all sorts of IO stuff) + stdio_filebuf (=streambuf)
+
+#endif
+
+#elif !defined(__ANDROID__)
+#include <wordexp.h>
+#endif
+
+#if defined(__sparcv9)
+// Big endian
+#else
+#if (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) || MINIZ_X86_OR_X64_CPU
+#define TINYGLTF_LITTLE_ENDIAN 1
+#endif
+#endif
+
+namespace {
+#ifdef TINYGLTF_USE_RAPIDJSON
+
+#ifdef TINYGLTF_USE_RAPIDJSON_CRTALLOCATOR
+// This uses the RapidJSON CRTAllocator.  It is thread safe and multiple
+// documents may be active at once.
+using json =
+    rapidjson::GenericValue<rapidjson::UTF8<>, rapidjson::CrtAllocator>;
+using json_const_iterator = json::ConstMemberIterator;
+using json_const_array_iterator = json const *;
+using JsonDocument =
+    rapidjson::GenericDocument<rapidjson::UTF8<>, rapidjson::CrtAllocator>;
+rapidjson::CrtAllocator s_CrtAllocator;  // stateless and thread safe
+rapidjson::CrtAllocator &GetAllocator() { return s_CrtAllocator; }
+#else
+// This uses the default RapidJSON MemoryPoolAllocator.  It is very fast, but
+// not thread safe. Only a single JsonDocument may be active at any one time,
+// meaning only a single gltf load/save can be active any one time.
+using json = rapidjson::Value;
+using json_const_iterator = json::ConstMemberIterator;
+using json_const_array_iterator = json const *;
+rapidjson::Document *s_pActiveDocument = nullptr;
+rapidjson::Document::AllocatorType &GetAllocator() {
+  assert(s_pActiveDocument);  // Root json node must be JsonDocument type
+  return s_pActiveDocument->GetAllocator();
+}
+
+#ifdef __clang__
+#pragma clang diagnostic push
+// Suppress JsonDocument(JsonDocument &&rhs) noexcept
+#pragma clang diagnostic ignored "-Wunused-member-function"
+#endif
+
+struct JsonDocument : public rapidjson::Document {
+  JsonDocument() {
+    assert(s_pActiveDocument ==
+           nullptr);  // When using default allocator, only one document can be
+                      // active at a time, if you need multiple active at once,
+                      // define TINYGLTF_USE_RAPIDJSON_CRTALLOCATOR
+    s_pActiveDocument = this;
+  }
+  JsonDocument(const JsonDocument &) = delete;
+  JsonDocument(JsonDocument &&rhs) noexcept
+      : rapidjson::Document(std::move(rhs)) {
+    s_pActiveDocument = this;
+    rhs.isNil = true;
+  }
+  ~JsonDocument() {
+    if (!isNil) {
+      s_pActiveDocument = nullptr;
+    }
+  }
+
+ private:
+  bool isNil = false;
+};
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#endif  // TINYGLTF_USE_RAPIDJSON_CRTALLOCATOR
+
+#else
+using nlohmann::json;
+using json_const_iterator = json::const_iterator;
+using json_const_array_iterator = json_const_iterator;
+using JsonDocument = json;
+#endif
+
+void JsonParse(JsonDocument &doc, const char *str, size_t length,
+               bool throwExc = false) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  (void)throwExc;
+  doc.Parse(str, length);
+#else
+  doc = json::parse(str, str + length, nullptr, throwExc);
+#endif
+}
+}  // namespace
+
+#ifdef __APPLE__
+#include "TargetConditionals.h"
+#endif
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc++98-compat"
+#endif
+
+namespace tinygltf {
+
+// Equals function for Value, for recursivity
+static bool Equals(const tinygltf::Value &one, const tinygltf::Value &other) {
+  if (one.Type() != other.Type()) return false;
+
+  switch (one.Type()) {
+    case NULL_TYPE:
+      return true;
+    case BOOL_TYPE:
+      return one.Get<bool>() == other.Get<bool>();
+    case REAL_TYPE:
+      return TINYGLTF_DOUBLE_EQUAL(one.Get<double>(), other.Get<double>());
+    case INT_TYPE:
+      return one.Get<int>() == other.Get<int>();
+    case OBJECT_TYPE: {
+      auto oneObj = one.Get<tinygltf::Value::Object>();
+      auto otherObj = other.Get<tinygltf::Value::Object>();
+      if (oneObj.size() != otherObj.size()) return false;
+      for (auto &it : oneObj) {
+        auto otherIt = otherObj.find(it.first);
+        if (otherIt == otherObj.end()) return false;
+
+        if (!Equals(it.second, otherIt->second)) return false;
+      }
+      return true;
+    }
+    case ARRAY_TYPE: {
+      if (one.Size() != other.Size()) return false;
+      for (int i = 0; i < int(one.Size()); ++i)
+        if (!Equals(one.Get(i), other.Get(i))) return false;
+      return true;
+    }
+    case STRING_TYPE:
+      return one.Get<std::string>() == other.Get<std::string>();
+    case BINARY_TYPE:
+      return one.Get<std::vector<unsigned char> >() ==
+             other.Get<std::vector<unsigned char> >();
+    default: {
+      // unhandled type
+      return false;
+    }
+  }
+}
+
+// Equals function for std::vector<double> using TINYGLTF_DOUBLE_EPSILON
+static bool Equals(const std::vector<double> &one,
+                   const std::vector<double> &other) {
+  if (one.size() != other.size()) return false;
+  for (int i = 0; i < int(one.size()); ++i) {
+    if (!TINYGLTF_DOUBLE_EQUAL(one[size_t(i)], other[size_t(i)])) return false;
+  }
+  return true;
+}
+
+bool Accessor::operator==(const Accessor &other) const {
+  return this->bufferView == other.bufferView &&
+         this->byteOffset == other.byteOffset &&
+         this->componentType == other.componentType &&
+         this->count == other.count && this->extensions == other.extensions &&
+         this->extras == other.extras &&
+         Equals(this->maxValues, other.maxValues) &&
+         Equals(this->minValues, other.minValues) && this->name == other.name &&
+         this->normalized == other.normalized && this->type == other.type;
+}
+bool Animation::operator==(const Animation &other) const {
+  return this->channels == other.channels &&
+         this->extensions == other.extensions && this->extras == other.extras &&
+         this->name == other.name && this->samplers == other.samplers;
+}
+bool AnimationChannel::operator==(const AnimationChannel &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->target_node == other.target_node &&
+         this->target_path == other.target_path &&
+         this->sampler == other.sampler;
+}
+bool AnimationSampler::operator==(const AnimationSampler &other) const {
+  return this->extras == other.extras && this->extensions == other.extensions &&
+         this->input == other.input &&
+         this->interpolation == other.interpolation &&
+         this->output == other.output;
+}
+bool Asset::operator==(const Asset &other) const {
+  return this->copyright == other.copyright &&
+         this->extensions == other.extensions && this->extras == other.extras &&
+         this->generator == other.generator &&
+         this->minVersion == other.minVersion && this->version == other.version;
+}
+bool Buffer::operator==(const Buffer &other) const {
+  return this->data == other.data && this->extensions == other.extensions &&
+         this->extras == other.extras && this->name == other.name &&
+         this->uri == other.uri;
+}
+bool BufferView::operator==(const BufferView &other) const {
+  return this->buffer == other.buffer && this->byteLength == other.byteLength &&
+         this->byteOffset == other.byteOffset &&
+         this->byteStride == other.byteStride && this->name == other.name &&
+         this->target == other.target && this->extensions == other.extensions &&
+         this->extras == other.extras &&
+         this->dracoDecoded == other.dracoDecoded;
+}
+bool Camera::operator==(const Camera &other) const {
+  return this->name == other.name && this->extensions == other.extensions &&
+         this->extras == other.extras &&
+         this->orthographic == other.orthographic &&
+         this->perspective == other.perspective && this->type == other.type;
+}
+bool Image::operator==(const Image &other) const {
+  return this->bufferView == other.bufferView &&
+         this->component == other.component &&
+         this->extensions == other.extensions && this->extras == other.extras &&
+         this->height == other.height && this->image == other.image &&
+         this->mimeType == other.mimeType && this->name == other.name &&
+         this->uri == other.uri && this->width == other.width;
+}
+bool Light::operator==(const Light &other) const {
+  return Equals(this->color, other.color) && this->name == other.name &&
+         this->type == other.type;
+}
+bool Material::operator==(const Material &other) const {
+  return (this->pbrMetallicRoughness == other.pbrMetallicRoughness) &&
+         (this->normalTexture == other.normalTexture) &&
+         (this->occlusionTexture == other.occlusionTexture) &&
+         (this->emissiveTexture == other.emissiveTexture) &&
+         Equals(this->emissiveFactor, other.emissiveFactor) &&
+         (this->alphaMode == other.alphaMode) &&
+         TINYGLTF_DOUBLE_EQUAL(this->alphaCutoff, other.alphaCutoff) &&
+         (this->doubleSided == other.doubleSided) &&
+         (this->extensions == other.extensions) &&
+         (this->extras == other.extras) && (this->values == other.values) &&
+         (this->additionalValues == other.additionalValues) &&
+         (this->name == other.name);
+}
+bool Mesh::operator==(const Mesh &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->name == other.name && Equals(this->weights, other.weights) &&
+         this->primitives == other.primitives;
+}
+bool Model::operator==(const Model &other) const {
+  return this->accessors == other.accessors &&
+         this->animations == other.animations && this->asset == other.asset &&
+         this->buffers == other.buffers &&
+         this->bufferViews == other.bufferViews &&
+         this->cameras == other.cameras &&
+         this->defaultScene == other.defaultScene &&
+         this->extensions == other.extensions &&
+         this->extensionsRequired == other.extensionsRequired &&
+         this->extensionsUsed == other.extensionsUsed &&
+         this->extras == other.extras && this->images == other.images &&
+         this->lights == other.lights && this->materials == other.materials &&
+         this->meshes == other.meshes && this->nodes == other.nodes &&
+         this->samplers == other.samplers && this->scenes == other.scenes &&
+         this->skins == other.skins && this->textures == other.textures;
+}
+bool Node::operator==(const Node &other) const {
+  return this->camera == other.camera && this->children == other.children &&
+         this->extensions == other.extensions && this->extras == other.extras &&
+         Equals(this->matrix, other.matrix) && this->mesh == other.mesh &&
+         this->name == other.name && Equals(this->rotation, other.rotation) &&
+         Equals(this->scale, other.scale) && this->skin == other.skin &&
+         Equals(this->translation, other.translation) &&
+         Equals(this->weights, other.weights);
+}
+bool SpotLight::operator==(const SpotLight &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         TINYGLTF_DOUBLE_EQUAL(this->innerConeAngle, other.innerConeAngle) &&
+         TINYGLTF_DOUBLE_EQUAL(this->outerConeAngle, other.outerConeAngle);
+}
+bool OrthographicCamera::operator==(const OrthographicCamera &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         TINYGLTF_DOUBLE_EQUAL(this->xmag, other.xmag) &&
+         TINYGLTF_DOUBLE_EQUAL(this->ymag, other.ymag) &&
+         TINYGLTF_DOUBLE_EQUAL(this->zfar, other.zfar) &&
+         TINYGLTF_DOUBLE_EQUAL(this->znear, other.znear);
+}
+bool Parameter::operator==(const Parameter &other) const {
+  if (this->bool_value != other.bool_value ||
+      this->has_number_value != other.has_number_value)
+    return false;
+
+  if (!TINYGLTF_DOUBLE_EQUAL(this->number_value, other.number_value))
+    return false;
+
+  if (this->json_double_value.size() != other.json_double_value.size())
+    return false;
+  for (auto &it : this->json_double_value) {
+    auto otherIt = other.json_double_value.find(it.first);
+    if (otherIt == other.json_double_value.end()) return false;
+
+    if (!TINYGLTF_DOUBLE_EQUAL(it.second, otherIt->second)) return false;
+  }
+
+  if (!Equals(this->number_array, other.number_array)) return false;
+
+  if (this->string_value != other.string_value) return false;
+
+  return true;
+}
+bool PerspectiveCamera::operator==(const PerspectiveCamera &other) const {
+  return TINYGLTF_DOUBLE_EQUAL(this->aspectRatio, other.aspectRatio) &&
+         this->extensions == other.extensions && this->extras == other.extras &&
+         TINYGLTF_DOUBLE_EQUAL(this->yfov, other.yfov) &&
+         TINYGLTF_DOUBLE_EQUAL(this->zfar, other.zfar) &&
+         TINYGLTF_DOUBLE_EQUAL(this->znear, other.znear);
+}
+bool Primitive::operator==(const Primitive &other) const {
+  return this->attributes == other.attributes && this->extras == other.extras &&
+         this->indices == other.indices && this->material == other.material &&
+         this->mode == other.mode && this->targets == other.targets;
+}
+bool Sampler::operator==(const Sampler &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->magFilter == other.magFilter &&
+         this->minFilter == other.minFilter && this->name == other.name &&
+         this->wrapR == other.wrapR && this->wrapS == other.wrapS &&
+         this->wrapT == other.wrapT;
+}
+bool Scene::operator==(const Scene &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->name == other.name && this->nodes == other.nodes;
+}
+bool Skin::operator==(const Skin &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->inverseBindMatrices == other.inverseBindMatrices &&
+         this->joints == other.joints && this->name == other.name &&
+         this->skeleton == other.skeleton;
+}
+bool Texture::operator==(const Texture &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->name == other.name && this->sampler == other.sampler &&
+         this->source == other.source;
+}
+bool TextureInfo::operator==(const TextureInfo &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->index == other.index && this->texCoord == other.texCoord;
+}
+bool NormalTextureInfo::operator==(const NormalTextureInfo &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->index == other.index && this->texCoord == other.texCoord &&
+         TINYGLTF_DOUBLE_EQUAL(this->scale, other.scale);
+}
+bool OcclusionTextureInfo::operator==(const OcclusionTextureInfo &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         this->index == other.index && this->texCoord == other.texCoord &&
+         TINYGLTF_DOUBLE_EQUAL(this->strength, other.strength);
+}
+bool PbrMetallicRoughness::operator==(const PbrMetallicRoughness &other) const {
+  return this->extensions == other.extensions && this->extras == other.extras &&
+         (this->baseColorTexture == other.baseColorTexture) &&
+         (this->metallicRoughnessTexture == other.metallicRoughnessTexture) &&
+         Equals(this->baseColorFactor, other.baseColorFactor) &&
+         TINYGLTF_DOUBLE_EQUAL(this->metallicFactor, other.metallicFactor) &&
+         TINYGLTF_DOUBLE_EQUAL(this->roughnessFactor, other.roughnessFactor);
+}
+bool Value::operator==(const Value &other) const {
+  return Equals(*this, other);
+}
+
+static void swap4(unsigned int *val) {
+#ifdef TINYGLTF_LITTLE_ENDIAN
+  (void)val;
+#else
+  unsigned int tmp = *val;
+  unsigned char *dst = reinterpret_cast<unsigned char *>(val);
+  unsigned char *src = reinterpret_cast<unsigned char *>(&tmp);
+
+  dst[0] = src[3];
+  dst[1] = src[2];
+  dst[2] = src[1];
+  dst[3] = src[0];
+#endif
+}
+
+static std::string JoinPath(const std::string &path0,
+                            const std::string &path1) {
+  if (path0.empty()) {
+    return path1;
+  } else {
+    // check '/'
+    char lastChar = *path0.rbegin();
+    if (lastChar != '/') {
+      return path0 + std::string("/") + path1;
+    } else {
+      return path0 + path1;
+    }
+  }
+}
+
+static std::string FindFile(const std::vector<std::string> &paths,
+                            const std::string &filepath, FsCallbacks *fs) {
+  if (fs == nullptr || fs->ExpandFilePath == nullptr ||
+      fs->FileExists == nullptr) {
+    // Error, fs callback[s] missing
+    return std::string();
+  }
+
+  for (size_t i = 0; i < paths.size(); i++) {
+    std::string absPath =
+        fs->ExpandFilePath(JoinPath(paths[i], filepath), fs->user_data);
+    if (fs->FileExists(absPath, fs->user_data)) {
+      return absPath;
+    }
+  }
+
+  return std::string();
+}
+
+static std::string GetFilePathExtension(const std::string &FileName) {
+  if (FileName.find_last_of(".") != std::string::npos)
+    return FileName.substr(FileName.find_last_of(".") + 1);
+  return "";
+}
+
+static std::string GetBaseDir(const std::string &filepath) {
+  if (filepath.find_last_of("/\\") != std::string::npos)
+    return filepath.substr(0, filepath.find_last_of("/\\"));
+  return "";
+}
+
+// https://stackoverflow.com/questions/8520560/get-a-file-name-from-a-path
+static std::string GetBaseFilename(const std::string &filepath) {
+  return filepath.substr(filepath.find_last_of("/\\") + 1);
+}
+
+std::string base64_encode(unsigned char const *, unsigned int len);
+std::string base64_decode(std::string const &s);
+
+/*
+   base64.cpp and base64.h
+
+   Copyright (C) 2004-2008 René Nyffenegger
+
+   This source code is provided 'as-is', without any express or implied
+   warranty. In no event will the author be held liable for any damages
+   arising from the use of this software.
+
+   Permission is granted to anyone to use this software for any purpose,
+   including commercial applications, and to alter it and redistribute it
+   freely, subject to the following restrictions:
+
+   1. The origin of this source code must not be misrepresented; you must not
+      claim that you wrote the original source code. If you use this source code
+      in a product, an acknowledgment in the product documentation would be
+      appreciated but is not required.
+
+   2. Altered source versions must be plainly marked as such, and must not be
+      misrepresented as being the original source code.
+
+   3. This notice may not be removed or altered from any source distribution.
+
+   René Nyffenegger rene.nyffenegger@adp-gmbh.ch
+
+*/
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wsign-conversion"
+#pragma clang diagnostic ignored "-Wconversion"
+#endif
+
+static inline bool is_base64(unsigned char c) {
+  return (isalnum(c) || (c == '+') || (c == '/'));
+}
+
+std::string base64_encode(unsigned char const *bytes_to_encode,
+                          unsigned int in_len) {
+  std::string ret;
+  int i = 0;
+  int j = 0;
+  unsigned char char_array_3[3];
+  unsigned char char_array_4[4];
+
+  const char *base64_chars =
+      "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+      "abcdefghijklmnopqrstuvwxyz"
+      "0123456789+/";
+
+  while (in_len--) {
+    char_array_3[i++] = *(bytes_to_encode++);
+    if (i == 3) {
+      char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
+      char_array_4[1] =
+          ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
+      char_array_4[2] =
+          ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
+      char_array_4[3] = char_array_3[2] & 0x3f;
+
+      for (i = 0; (i < 4); i++) ret += base64_chars[char_array_4[i]];
+      i = 0;
+    }
+  }
+
+  if (i) {
+    for (j = i; j < 3; j++) char_array_3[j] = '\0';
+
+    char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
+    char_array_4[1] =
+        ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
+    char_array_4[2] =
+        ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
+
+    for (j = 0; (j < i + 1); j++) ret += base64_chars[char_array_4[j]];
+
+    while ((i++ < 3)) ret += '=';
+  }
+
+  return ret;
+}
+
+std::string base64_decode(std::string const &encoded_string) {
+  int in_len = static_cast<int>(encoded_string.size());
+  int i = 0;
+  int j = 0;
+  int in_ = 0;
+  unsigned char char_array_4[4], char_array_3[3];
+  std::string ret;
+
+  const std::string base64_chars =
+      "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+      "abcdefghijklmnopqrstuvwxyz"
+      "0123456789+/";
+
+  while (in_len-- && (encoded_string[in_] != '=') &&
+         is_base64(encoded_string[in_])) {
+    char_array_4[i++] = encoded_string[in_];
+    in_++;
+    if (i == 4) {
+      for (i = 0; i < 4; i++)
+        char_array_4[i] =
+            static_cast<unsigned char>(base64_chars.find(char_array_4[i]));
+
+      char_array_3[0] =
+          (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
+      char_array_3[1] =
+          ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
+      char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
+
+      for (i = 0; (i < 3); i++) ret += char_array_3[i];
+      i = 0;
+    }
+  }
+
+  if (i) {
+    for (j = i; j < 4; j++) char_array_4[j] = 0;
+
+    for (j = 0; j < 4; j++)
+      char_array_4[j] =
+          static_cast<unsigned char>(base64_chars.find(char_array_4[j]));
+
+    char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
+    char_array_3[1] =
+        ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
+    char_array_3[2] = ((char_array_4[2] & 0x3) << 6) + char_array_4[3];
+
+    for (j = 0; (j < i - 1); j++) ret += char_array_3[j];
+  }
+
+  return ret;
+}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+// https://github.com/syoyo/tinygltf/issues/228
+// TODO(syoyo): Use uriparser https://uriparser.github.io/ for stricter Uri
+// decoding?
+//
+// https://stackoverflow.com/questions/18307429/encode-decode-url-in-c
+// http://dlib.net/dlib/server/server_http.cpp.html
+
+// --- dlib beign ------------------------------------------------------------
+// Copyright (C) 2003  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+
+namespace dlib {
+
+#if 0
+        inline unsigned char to_hex( unsigned char x )
+        {
+            return x + (x > 9 ? ('A'-10) : '0');
+        }
+
+        const std::string urlencode( const std::string& s )
+        {
+            std::ostringstream os;
+
+            for ( std::string::const_iterator ci = s.begin(); ci != s.end(); ++ci )
+            {
+                if ( (*ci >= 'a' && *ci <= 'z') ||
+                     (*ci >= 'A' && *ci <= 'Z') ||
+                     (*ci >= '0' && *ci <= '9') )
+                { // allowed
+                    os << *ci;
+                }
+                else if ( *ci == ' ')
+                {
+                    os << '+';
+                }
+                else
+                {
+                    os << '%' << to_hex(static_cast<unsigned char>(*ci >> 4)) << to_hex(static_cast<unsigned char>(*ci % 16));
+                }
+            }
+
+            return os.str();
+        }
+#endif
+
+inline unsigned char from_hex(unsigned char ch) {
+  if (ch <= '9' && ch >= '0')
+    ch -= '0';
+  else if (ch <= 'f' && ch >= 'a')
+    ch -= 'a' - 10;
+  else if (ch <= 'F' && ch >= 'A')
+    ch -= 'A' - 10;
+  else
+    ch = 0;
+  return ch;
+}
+
+static const std::string urldecode(const std::string &str) {
+  using namespace std;
+  string result;
+  string::size_type i;
+  for (i = 0; i < str.size(); ++i) {
+    if (str[i] == '+') {
+      result += ' ';
+    } else if (str[i] == '%' && str.size() > i + 2) {
+      const unsigned char ch1 =
+          from_hex(static_cast<unsigned char>(str[i + 1]));
+      const unsigned char ch2 =
+          from_hex(static_cast<unsigned char>(str[i + 2]));
+      const unsigned char ch = static_cast<unsigned char>((ch1 << 4) | ch2);
+      result += static_cast<char>(ch);
+      i += 2;
+    } else {
+      result += str[i];
+    }
+  }
+  return result;
+}
+
+}  // namespace dlib
+// --- dlib end --------------------------------------------------------------
+
+static bool LoadExternalFile(std::vector<unsigned char> *out, std::string *err,
+                             std::string *warn, const std::string &filename,
+                             const std::string &basedir, bool required,
+                             size_t reqBytes, bool checkSize, FsCallbacks *fs) {
+  if (fs == nullptr || fs->FileExists == nullptr ||
+      fs->ExpandFilePath == nullptr || fs->ReadWholeFile == nullptr) {
+    // This is a developer error, assert() ?
+    if (err) {
+      (*err) += "FS callback[s] not set\n";
+    }
+    return false;
+  }
+
+  std::string *failMsgOut = required ? err : warn;
+
+  out->clear();
+
+  std::vector<std::string> paths;
+  paths.push_back(basedir);
+  paths.push_back(".");
+
+  std::string filepath = FindFile(paths, filename, fs);
+  if (filepath.empty() || filename.empty()) {
+    if (failMsgOut) {
+      (*failMsgOut) += "File not found : " + filename + "\n";
+    }
+    return false;
+  }
+
+  std::vector<unsigned char> buf;
+  std::string fileReadErr;
+  bool fileRead =
+      fs->ReadWholeFile(&buf, &fileReadErr, filepath, fs->user_data);
+  if (!fileRead) {
+    if (failMsgOut) {
+      (*failMsgOut) +=
+          "File read error : " + filepath + " : " + fileReadErr + "\n";
+    }
+    return false;
+  }
+
+  size_t sz = buf.size();
+  if (sz == 0) {
+    if (failMsgOut) {
+      (*failMsgOut) += "File is empty : " + filepath + "\n";
+    }
+    return false;
+  }
+
+  if (checkSize) {
+    if (reqBytes == sz) {
+      out->swap(buf);
+      return true;
+    } else {
+      std::stringstream ss;
+      ss << "File size mismatch : " << filepath << ", requestedBytes "
+         << reqBytes << ", but got " << sz << std::endl;
+      if (failMsgOut) {
+        (*failMsgOut) += ss.str();
+      }
+      return false;
+    }
+  }
+
+  out->swap(buf);
+  return true;
+}
+
+void TinyGLTF::SetImageLoader(LoadImageDataFunction func, void *user_data) {
+  LoadImageData = func;
+  load_image_user_data_ = user_data;
+}
+
+#ifndef TINYGLTF_NO_STB_IMAGE
+bool LoadImageData(Image *image, const int image_idx, std::string *err,
+                   std::string *warn, int req_width, int req_height,
+                   const unsigned char *bytes, int size, void *user_data) {
+  (void)user_data;
+  (void)warn;
+
+  int w = 0, h = 0, comp = 0, req_comp = 0;
+
+  unsigned char *data = nullptr;
+
+  // force 32-bit textures for common Vulkan compatibility. It appears that
+  // some GPU drivers do not support 24-bit images for Vulkan
+  req_comp = 4;
+  int bits = 8;
+  int pixel_type = TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE;
+
+  // It is possible that the image we want to load is a 16bit per channel image
+  // We are going to attempt to load it as 16bit per channel, and if it worked,
+  // set the image data accodingly. We are casting the returned pointer into
+  // unsigned char, because we are representing "bytes". But we are updating
+  // the Image metadata to signal that this image uses 2 bytes (16bits) per
+  // channel:
+  if (stbi_is_16_bit_from_memory(bytes, size)) {
+    data = reinterpret_cast<unsigned char *>(
+        stbi_load_16_from_memory(bytes, size, &w, &h, &comp, req_comp));
+    if (data) {
+      bits = 16;
+      pixel_type = TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT;
+    }
+  }
+
+  // at this point, if data is still NULL, it means that the image wasn't
+  // 16bit per channel, we are going to load it as a normal 8bit per channel
+  // mage as we used to do:
+  // if image cannot be decoded, ignore parsing and keep it by its path
+  // don't break in this case
+  // FIXME we should only enter this function if the image is embedded. If
+  // image->uri references
+  // an image file, it should be left as it is. Image loading should not be
+  // mandatory (to support other formats)
+  if (!data) data = stbi_load_from_memory(bytes, size, &w, &h, &comp, req_comp);
+  if (!data) {
+    // NOTE: you can use `warn` instead of `err`
+    if (err) {
+      (*err) +=
+          "Unknown image format. STB cannot decode image data for image[" +
+          std::to_string(image_idx) + "] name = \"" + image->name + "\".\n";
+    }
+    return false;
+  }
+
+  if ((w < 1) || (h < 1)) {
+    stbi_image_free(data);
+    if (err) {
+      (*err) += "Invalid image data for image[" + std::to_string(image_idx) +
+                "] name = \"" + image->name + "\"\n";
+    }
+    return false;
+  }
+
+  if (req_width > 0) {
+    if (req_width != w) {
+      stbi_image_free(data);
+      if (err) {
+        (*err) += "Image width mismatch for image[" +
+                  std::to_string(image_idx) + "] name = \"" + image->name +
+                  "\"\n";
+      }
+      return false;
+    }
+  }
+
+  if (req_height > 0) {
+    if (req_height != h) {
+      stbi_image_free(data);
+      if (err) {
+        (*err) += "Image height mismatch. for image[" +
+                  std::to_string(image_idx) + "] name = \"" + image->name +
+                  "\"\n";
+      }
+      return false;
+    }
+  }
+
+  image->width = w;
+  image->height = h;
+  image->component = req_comp;
+  image->bits = bits;
+  image->pixel_type = pixel_type;
+  image->image.resize(static_cast<size_t>(w * h * req_comp) * size_t(bits / 8));
+  std::copy(data, data + w * h * req_comp * (bits / 8), image->image.begin());
+  stbi_image_free(data);
+
+  return true;
+}
+#endif
+
+void TinyGLTF::SetImageWriter(WriteImageDataFunction func, void *user_data) {
+  WriteImageData = func;
+  write_image_user_data_ = user_data;
+}
+
+#ifndef TINYGLTF_NO_STB_IMAGE_WRITE
+static void WriteToMemory_stbi(void *context, void *data, int size) {
+  std::vector<unsigned char> *buffer =
+      reinterpret_cast<std::vector<unsigned char> *>(context);
+
+  unsigned char *pData = reinterpret_cast<unsigned char *>(data);
+
+  buffer->insert(buffer->end(), pData, pData + size);
+}
+
+bool WriteImageData(const std::string *basepath, const std::string *filename,
+                    Image *image, bool embedImages, void *fsPtr) {
+  const std::string ext = GetFilePathExtension(*filename);
+
+  // Write image to temporary buffer
+  std::string header;
+  std::vector<unsigned char> data;
+
+  if (ext == "png") {
+    if ((image->bits != 8) ||
+        (image->pixel_type != TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE)) {
+      // Unsupported pixel format
+      return false;
+    }
+
+    if (!stbi_write_png_to_func(WriteToMemory_stbi, &data, image->width,
+                                image->height, image->component,
+                                &image->image[0], 0)) {
+      return false;
+    }
+    header = "data:image/png;base64,";
+  } else if (ext == "jpg") {
+    if (!stbi_write_jpg_to_func(WriteToMemory_stbi, &data, image->width,
+                                image->height, image->component,
+                                &image->image[0], 100)) {
+      return false;
+    }
+    header = "data:image/jpeg;base64,";
+  } else if (ext == "bmp") {
+    if (!stbi_write_bmp_to_func(WriteToMemory_stbi, &data, image->width,
+                                image->height, image->component,
+                                &image->image[0])) {
+      return false;
+    }
+    header = "data:image/bmp;base64,";
+  } else if (!embedImages) {
+    // Error: can't output requested format to file
+    return false;
+  }
+
+  if (embedImages) {
+    // Embed base64-encoded image into URI
+    if (data.size()) {
+      image->uri =
+          header +
+          base64_encode(&data[0], static_cast<unsigned int>(data.size()));
+    } else {
+      // Throw error?
+    }
+  } else {
+    // Write image to disc
+    FsCallbacks *fs = reinterpret_cast<FsCallbacks *>(fsPtr);
+    if ((fs != nullptr) && (fs->WriteWholeFile != nullptr)) {
+      const std::string imagefilepath = JoinPath(*basepath, *filename);
+      std::string writeError;
+      if (!fs->WriteWholeFile(&writeError, imagefilepath, data,
+                              fs->user_data)) {
+        // Could not write image file to disc; Throw error ?
+        return false;
+      }
+    } else {
+      // Throw error?
+    }
+    image->uri = *filename;
+  }
+
+  return true;
+}
+#endif
+
+void TinyGLTF::SetFsCallbacks(FsCallbacks callbacks) { fs = callbacks; }
+
+#ifdef _WIN32
+static inline std::wstring UTF8ToWchar(const std::string &str) {
+  int wstr_size =
+      MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), nullptr, 0);
+  std::wstring wstr(wstr_size, 0);
+  MultiByteToWideChar(CP_UTF8, 0, str.data(), (int)str.size(), &wstr[0],
+                      (int)wstr.size());
+  return wstr;
+}
+
+static inline std::string WcharToUTF8(const std::wstring &wstr) {
+  int str_size = WideCharToMultiByte(CP_UTF8, 0, wstr.data(), (int)wstr.size(),
+                                     nullptr, 0, NULL, NULL);
+  std::string str(str_size, 0);
+  WideCharToMultiByte(CP_UTF8, 0, wstr.data(), (int)wstr.size(), &str[0],
+                      (int)str.size(), NULL, NULL);
+  return str;
+}
+#endif
+
+#ifndef TINYGLTF_NO_FS
+// Default implementations of filesystem functions
+
+bool FileExists(const std::string &abs_filename, void *) {
+  bool ret;
+#ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
+  if (asset_manager) {
+    AAsset *asset = AAssetManager_open(asset_manager, abs_filename.c_str(),
+                                       AASSET_MODE_STREAMING);
+    if (!asset) {
+      return false;
+    }
+    AAsset_close(asset);
+    ret = true;
+  } else {
+    return false;
+  }
+#else
+#ifdef _WIN32
+#if defined(_MSC_VER) || defined(__GLIBCXX__)
+  FILE *fp = nullptr;
+  errno_t err = _wfopen_s(&fp, UTF8ToWchar(abs_filename).c_str(), L"rb");
+  if (err != 0) {
+    return false;
+  }
+#else
+  FILE *fp = nullptr;
+  errno_t err = fopen_s(&fp, abs_filename.c_str(), "rb");
+  if (err != 0) {
+    return false;
+  }
+#endif
+
+#else
+  FILE *fp = fopen(abs_filename.c_str(), "rb");
+#endif
+  if (fp) {
+    ret = true;
+    fclose(fp);
+  } else {
+    ret = false;
+  }
+#endif
+
+  return ret;
+}
+
+std::string ExpandFilePath(const std::string &filepath, void *) {
+#ifdef _WIN32
+  // Assume input `filepath` is encoded in UTF-8
+  std::wstring wfilepath = UTF8ToWchar(filepath);
+  DWORD wlen = ExpandEnvironmentStringsW(wfilepath.c_str(), nullptr, 0);
+  wchar_t *wstr = new wchar_t[wlen];
+  ExpandEnvironmentStringsW(wfilepath.c_str(), wstr, wlen);
+
+  std::wstring ws(wstr);
+  delete[] wstr;
+  return WcharToUTF8(ws);
+
+#else
+
+#if defined(TARGET_OS_IPHONE) || defined(TARGET_IPHONE_SIMULATOR) || \
+    defined(__ANDROID__) || defined(__EMSCRIPTEN__)
+  // no expansion
+  std::string s = filepath;
+#else
+  std::string s;
+  wordexp_t p;
+
+  if (filepath.empty()) {
+    return "";
+  }
+
+  // Quote the string to keep any spaces in filepath intact.
+  std::string quoted_path = "\"" + filepath + "\"";
+  // char** w;
+  int ret = wordexp(quoted_path.c_str(), &p, 0);
+  if (ret) {
+    // err
+    s = filepath;
+    return s;
+  }
+
+  // Use first element only.
+  if (p.we_wordv) {
+    s = std::string(p.we_wordv[0]);
+    wordfree(&p);
+  } else {
+    s = filepath;
+  }
+
+#endif
+
+  return s;
+#endif
+}
+
+bool ReadWholeFile(std::vector<unsigned char> *out, std::string *err,
+                   const std::string &filepath, void *) {
+#ifdef TINYGLTF_ANDROID_LOAD_FROM_ASSETS
+  if (asset_manager) {
+    AAsset *asset = AAssetManager_open(asset_manager, filepath.c_str(),
+                                       AASSET_MODE_STREAMING);
+    if (!asset) {
+      if (err) {
+        (*err) += "File open error : " + filepath + "\n";
+      }
+      return false;
+    }
+    size_t size = AAsset_getLength(asset);
+    if (size == 0) {
+      if (err) {
+        (*err) += "Invalid file size : " + filepath +
+                  " (does the path point to a directory?)";
+      }
+      return false;
+    }
+    out->resize(size);
+    AAsset_read(asset, reinterpret_cast<char *>(&out->at(0)), size);
+    AAsset_close(asset);
+    return true;
+  } else {
+    if (err) {
+      (*err) += "No asset manager specified : " + filepath + "\n";
+    }
+    return false;
+  }
+#else
+#ifdef _WIN32
+#if defined(__GLIBCXX__)  // mingw
+  int file_descriptor =
+      _wopen(UTF8ToWchar(filepath).c_str(), _O_RDONLY | _O_BINARY);
+  __gnu_cxx::stdio_filebuf<char> wfile_buf(file_descriptor, std::ios_base::in);
+  std::istream f(&wfile_buf);
+#elif defined(_MSC_VER) || defined(_LIBCPP_VERSION)
+  // For libcxx, assume _LIBCPP_HAS_OPEN_WITH_WCHAR is defined to accept
+  // `wchar_t *`
+  std::ifstream f(UTF8ToWchar(filepath).c_str(), std::ifstream::binary);
+#else
+  // Unknown compiler/runtime
+  std::ifstream f(filepath.c_str(), std::ifstream::binary);
+#endif
+#else
+  std::ifstream f(filepath.c_str(), std::ifstream::binary);
+#endif
+  if (!f) {
+    if (err) {
+      (*err) += "File open error : " + filepath + "\n";
+    }
+    return false;
+  }
+
+  f.seekg(0, f.end);
+  size_t sz = static_cast<size_t>(f.tellg());
+  f.seekg(0, f.beg);
+
+  if (int64_t(sz) < 0) {
+    if (err) {
+      (*err) += "Invalid file size : " + filepath +
+                " (does the path point to a directory?)";
+    }
+    return false;
+  } else if (sz == 0) {
+    if (err) {
+      (*err) += "File is empty : " + filepath + "\n";
+    }
+    return false;
+  }
+
+  out->resize(sz);
+  f.read(reinterpret_cast<char *>(&out->at(0)),
+         static_cast<std::streamsize>(sz));
+
+  return true;
+#endif
+}
+
+bool WriteWholeFile(std::string *err, const std::string &filepath,
+                    const std::vector<unsigned char> &contents, void *) {
+#ifdef _WIN32
+#if defined(__GLIBCXX__)  // mingw
+  int file_descriptor = _wopen(UTF8ToWchar(filepath).c_str(),
+                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
+  __gnu_cxx::stdio_filebuf<char> wfile_buf(
+      file_descriptor, std::ios_base::out | std::ios_base::binary);
+  std::ostream f(&wfile_buf);
+#elif defined(_MSC_VER)
+  std::ofstream f(UTF8ToWchar(filepath).c_str(), std::ofstream::binary);
+#else  // clang?
+  std::ofstream f(filepath.c_str(), std::ofstream::binary);
+#endif
+#else
+  std::ofstream f(filepath.c_str(), std::ofstream::binary);
+#endif
+  if (!f) {
+    if (err) {
+      (*err) += "File open error for writing : " + filepath + "\n";
+    }
+    return false;
+  }
+
+  f.write(reinterpret_cast<const char *>(&contents.at(0)),
+          static_cast<std::streamsize>(contents.size()));
+  if (!f) {
+    if (err) {
+      (*err) += "File write error: " + filepath + "\n";
+    }
+    return false;
+  }
+
+  return true;
+}
+
+#endif  // TINYGLTF_NO_FS
+
+static std::string MimeToExt(const std::string &mimeType) {
+  if (mimeType == "image/jpeg") {
+    return "jpg";
+  } else if (mimeType == "image/png") {
+    return "png";
+  } else if (mimeType == "image/bmp") {
+    return "bmp";
+  } else if (mimeType == "image/gif") {
+    return "gif";
+  }
+
+  return "";
+}
+
+static void UpdateImageObject(Image &image, std::string &baseDir, int index,
+                              bool embedImages,
+                              WriteImageDataFunction *WriteImageData = nullptr,
+                              void *user_data = nullptr) {
+  std::string filename;
+  std::string ext;
+  // If image has uri, use it it as a filename
+  if (image.uri.size()) {
+    filename = GetBaseFilename(image.uri);
+    ext = GetFilePathExtension(filename);
+  } else if (image.bufferView != -1) {
+    // If there's no URI and the data exists in a buffer,
+    // don't change properties or write images
+  } else if (image.name.size()) {
+    ext = MimeToExt(image.mimeType);
+    // Otherwise use name as filename
+    filename = image.name + "." + ext;
+  } else {
+    ext = MimeToExt(image.mimeType);
+    // Fallback to index of image as filename
+    filename = std::to_string(index) + "." + ext;
+  }
+
+  // If callback is set, modify image data object
+  if (*WriteImageData != nullptr && !filename.empty()) {
+    std::string uri;
+    (*WriteImageData)(&baseDir, &filename, &image, embedImages, user_data);
+  }
+}
+
+bool IsDataURI(const std::string &in) {
+  std::string header = "data:application/octet-stream;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  header = "data:image/jpeg;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  header = "data:image/png;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  header = "data:image/bmp;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  header = "data:image/gif;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  header = "data:text/plain;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  header = "data:application/gltf-buffer;base64,";
+  if (in.find(header) == 0) {
+    return true;
+  }
+
+  return false;
+}
+
+bool DecodeDataURI(std::vector<unsigned char> *out, std::string &mime_type,
+                   const std::string &in, size_t reqBytes, bool checkSize) {
+  std::string header = "data:application/octet-stream;base64,";
+  std::string data;
+  if (in.find(header) == 0) {
+    data = base64_decode(in.substr(header.size()));  // cut mime string.
+  }
+
+  if (data.empty()) {
+    header = "data:image/jpeg;base64,";
+    if (in.find(header) == 0) {
+      mime_type = "image/jpeg";
+      data = base64_decode(in.substr(header.size()));  // cut mime string.
+    }
+  }
+
+  if (data.empty()) {
+    header = "data:image/png;base64,";
+    if (in.find(header) == 0) {
+      mime_type = "image/png";
+      data = base64_decode(in.substr(header.size()));  // cut mime string.
+    }
+  }
+
+  if (data.empty()) {
+    header = "data:image/bmp;base64,";
+    if (in.find(header) == 0) {
+      mime_type = "image/bmp";
+      data = base64_decode(in.substr(header.size()));  // cut mime string.
+    }
+  }
+
+  if (data.empty()) {
+    header = "data:image/gif;base64,";
+    if (in.find(header) == 0) {
+      mime_type = "image/gif";
+      data = base64_decode(in.substr(header.size()));  // cut mime string.
+    }
+  }
+
+  if (data.empty()) {
+    header = "data:text/plain;base64,";
+    if (in.find(header) == 0) {
+      mime_type = "text/plain";
+      data = base64_decode(in.substr(header.size()));
+    }
+  }
+
+  if (data.empty()) {
+    header = "data:application/gltf-buffer;base64,";
+    if (in.find(header) == 0) {
+      data = base64_decode(in.substr(header.size()));
+    }
+  }
+
+  // TODO(syoyo): Allow empty buffer? #229
+  if (data.empty()) {
+    return false;
+  }
+
+  if (checkSize) {
+    if (data.size() != reqBytes) {
+      return false;
+    }
+    out->resize(reqBytes);
+  } else {
+    out->resize(data.size());
+  }
+  std::copy(data.begin(), data.end(), out->begin());
+  return true;
+}
+
+namespace {
+bool GetInt(const json &o, int &val) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  if (!o.IsDouble()) {
+    if (o.IsInt()) {
+      val = o.GetInt();
+      return true;
+    } else if (o.IsUint()) {
+      val = static_cast<int>(o.GetUint());
+      return true;
+    } else if (o.IsInt64()) {
+      val = static_cast<int>(o.GetInt64());
+      return true;
+    } else if (o.IsUint64()) {
+      val = static_cast<int>(o.GetUint64());
+      return true;
+    }
+  }
+
+  return false;
+#else
+  auto type = o.type();
+
+  if ((type == json::value_t::number_integer) ||
+      (type == json::value_t::number_unsigned)) {
+    val = static_cast<int>(o.get<int64_t>());
+    return true;
+  }
+
+  return false;
+#endif
+}
+
+#ifdef TINYGLTF_USE_RAPIDJSON
+bool GetDouble(const json &o, double &val) {
+  if (o.IsDouble()) {
+    val = o.GetDouble();
+    return true;
+  }
+
+  return false;
+}
+#endif
+
+bool GetNumber(const json &o, double &val) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  if (o.IsNumber()) {
+    val = o.GetDouble();
+    return true;
+  }
+
+  return false;
+#else
+  if (o.is_number()) {
+    val = o.get<double>();
+    return true;
+  }
+
+  return false;
+#endif
+}
+
+bool GetString(const json &o, std::string &val) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  if (o.IsString()) {
+    val = o.GetString();
+    return true;
+  }
+
+  return false;
+#else
+  if (o.type() == json::value_t::string) {
+    val = o.get<std::string>();
+    return true;
+  }
+
+  return false;
+#endif
+}
+
+bool IsArray(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.IsArray();
+#else
+  return o.is_array();
+#endif
+}
+
+json_const_array_iterator ArrayBegin(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.Begin();
+#else
+  return o.begin();
+#endif
+}
+
+json_const_array_iterator ArrayEnd(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.End();
+#else
+  return o.end();
+#endif
+}
+
+bool IsObject(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.IsObject();
+#else
+  return o.is_object();
+#endif
+}
+
+json_const_iterator ObjectBegin(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.MemberBegin();
+#else
+  return o.begin();
+#endif
+}
+
+json_const_iterator ObjectEnd(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.MemberEnd();
+#else
+  return o.end();
+#endif
+}
+
+// Making this a const char* results in a pointer to a temporary when
+// TINYGLTF_USE_RAPIDJSON is off.
+std::string GetKey(json_const_iterator &it) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return it->name.GetString();
+#else
+  return it.key().c_str();
+#endif
+}
+
+bool FindMember(const json &o, const char *member, json_const_iterator &it) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  if (!o.IsObject()) {
+    return false;
+  }
+  it = o.FindMember(member);
+  return it != o.MemberEnd();
+#else
+  it = o.find(member);
+  return it != o.end();
+#endif
+}
+
+const json &GetValue(json_const_iterator &it) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return it->value;
+#else
+  return it.value();
+#endif
+}
+
+std::string JsonToString(const json &o, int spacing = -1) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  using namespace rapidjson;
+  StringBuffer buffer;
+  if (spacing == -1) {
+    Writer<StringBuffer> writer(buffer);
+    o.Accept(writer);
+  } else {
+    PrettyWriter<StringBuffer> writer(buffer);
+    writer.SetIndent(' ', uint32_t(spacing));
+    o.Accept(writer);
+  }
+  return buffer.GetString();
+#else
+  return o.dump(spacing);
+#endif
+}
+
+}  // namespace
+
+static bool ParseJsonAsValue(Value *ret, const json &o) {
+  Value val{};
+#ifdef TINYGLTF_USE_RAPIDJSON
+  using rapidjson::Type;
+  switch (o.GetType()) {
+    case Type::kObjectType: {
+      Value::Object value_object;
+      for (auto it = o.MemberBegin(); it != o.MemberEnd(); ++it) {
+        Value entry;
+        ParseJsonAsValue(&entry, it->value);
+        if (entry.Type() != NULL_TYPE)
+          value_object.emplace(GetKey(it), std::move(entry));
+      }
+      if (value_object.size() > 0) val = Value(std::move(value_object));
+    } break;
+    case Type::kArrayType: {
+      Value::Array value_array;
+      value_array.reserve(o.Size());
+      for (auto it = o.Begin(); it != o.End(); ++it) {
+        Value entry;
+        ParseJsonAsValue(&entry, *it);
+        if (entry.Type() != NULL_TYPE)
+          value_array.emplace_back(std::move(entry));
+      }
+      if (value_array.size() > 0) val = Value(std::move(value_array));
+    } break;
+    case Type::kStringType:
+      val = Value(std::string(o.GetString()));
+      break;
+    case Type::kFalseType:
+    case Type::kTrueType:
+      val = Value(o.GetBool());
+      break;
+    case Type::kNumberType:
+      if (!o.IsDouble()) {
+        int i = 0;
+        GetInt(o, i);
+        val = Value(i);
+      } else {
+        double d = 0.0;
+        GetDouble(o, d);
+        val = Value(d);
+      }
+      break;
+    case Type::kNullType:
+      break;
+      // all types are covered, so no `case default`
+  }
+#else
+  switch (o.type()) {
+    case json::value_t::object: {
+      Value::Object value_object;
+      for (auto it = o.begin(); it != o.end(); it++) {
+        Value entry;
+        ParseJsonAsValue(&entry, it.value());
+        if (entry.Type() != NULL_TYPE)
+          value_object.emplace(it.key(), std::move(entry));
+      }
+      if (value_object.size() > 0) val = Value(std::move(value_object));
+    } break;
+    case json::value_t::array: {
+      Value::Array value_array;
+      value_array.reserve(o.size());
+      for (auto it = o.begin(); it != o.end(); it++) {
+        Value entry;
+        ParseJsonAsValue(&entry, it.value());
+        if (entry.Type() != NULL_TYPE)
+          value_array.emplace_back(std::move(entry));
+      }
+      if (value_array.size() > 0) val = Value(std::move(value_array));
+    } break;
+    case json::value_t::string:
+      val = Value(o.get<std::string>());
+      break;
+    case json::value_t::boolean:
+      val = Value(o.get<bool>());
+      break;
+    case json::value_t::number_integer:
+    case json::value_t::number_unsigned:
+      val = Value(static_cast<int>(o.get<int64_t>()));
+      break;
+    case json::value_t::number_float:
+      val = Value(o.get<double>());
+      break;
+    case json::value_t::null:
+    case json::value_t::discarded:
+      // default:
+      break;
+  }
+#endif
+  if (ret) *ret = std::move(val);
+
+  return val.Type() != NULL_TYPE;
+}
+
+static bool ParseExtrasProperty(Value *ret, const json &o) {
+  json_const_iterator it;
+  if (!FindMember(o, "extras", it)) {
+    return false;
+  }
+
+  return ParseJsonAsValue(ret, GetValue(it));
+}
+
+static bool ParseBooleanProperty(bool *ret, std::string *err, const json &o,
+                                 const std::string &property,
+                                 const bool required,
+                                 const std::string &parent_node = "") {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  auto &value = GetValue(it);
+
+  bool isBoolean;
+  bool boolValue = false;
+#ifdef TINYGLTF_USE_RAPIDJSON
+  isBoolean = value.IsBool();
+  if (isBoolean) {
+    boolValue = value.GetBool();
+  }
+#else
+  isBoolean = value.is_boolean();
+  if (isBoolean) {
+    boolValue = value.get<bool>();
+  }
+#endif
+  if (!isBoolean) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not a bool type.\n";
+      }
+    }
+    return false;
+  }
+
+  if (ret) {
+    (*ret) = boolValue;
+  }
+
+  return true;
+}
+
+static bool ParseIntegerProperty(int *ret, std::string *err, const json &o,
+                                 const std::string &property,
+                                 const bool required,
+                                 const std::string &parent_node = "") {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  int intValue;
+  bool isInt = GetInt(GetValue(it), intValue);
+  if (!isInt) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not an integer type.\n";
+      }
+    }
+    return false;
+  }
+
+  if (ret) {
+    (*ret) = intValue;
+  }
+
+  return true;
+}
+
+static bool ParseUnsignedProperty(size_t *ret, std::string *err, const json &o,
+                                  const std::string &property,
+                                  const bool required,
+                                  const std::string &parent_node = "") {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  auto &value = GetValue(it);
+
+  size_t uValue = 0;
+  bool isUValue;
+#ifdef TINYGLTF_USE_RAPIDJSON
+  isUValue = false;
+  if (value.IsUint()) {
+    uValue = value.GetUint();
+    isUValue = true;
+  } else if (value.IsUint64()) {
+    uValue = value.GetUint64();
+    isUValue = true;
+  }
+#else
+  isUValue = value.is_number_unsigned();
+  if (isUValue) {
+    uValue = value.get<size_t>();
+  }
+#endif
+  if (!isUValue) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not a positive integer.\n";
+      }
+    }
+    return false;
+  }
+
+  if (ret) {
+    (*ret) = uValue;
+  }
+
+  return true;
+}
+
+static bool ParseNumberProperty(double *ret, std::string *err, const json &o,
+                                const std::string &property,
+                                const bool required,
+                                const std::string &parent_node = "") {
+  json_const_iterator it;
+
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  double numberValue;
+  bool isNumber = GetNumber(GetValue(it), numberValue);
+
+  if (!isNumber) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not a number type.\n";
+      }
+    }
+    return false;
+  }
+
+  if (ret) {
+    (*ret) = numberValue;
+  }
+
+  return true;
+}
+
+static bool ParseNumberArrayProperty(std::vector<double> *ret, std::string *err,
+                                     const json &o, const std::string &property,
+                                     bool required,
+                                     const std::string &parent_node = "") {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  if (!IsArray(GetValue(it))) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not an array";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  ret->clear();
+  auto end = ArrayEnd(GetValue(it));
+  for (auto i = ArrayBegin(GetValue(it)); i != end; ++i) {
+    double numberValue;
+    const bool isNumber = GetNumber(*i, numberValue);
+    if (!isNumber) {
+      if (required) {
+        if (err) {
+          (*err) += "'" + property + "' property is not a number.\n";
+          if (!parent_node.empty()) {
+            (*err) += " in " + parent_node;
+          }
+          (*err) += ".\n";
+        }
+      }
+      return false;
+    }
+    ret->push_back(numberValue);
+  }
+
+  return true;
+}
+
+static bool ParseIntegerArrayProperty(std::vector<int> *ret, std::string *err,
+                                      const json &o,
+                                      const std::string &property,
+                                      bool required,
+                                      const std::string &parent_node = "") {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  if (!IsArray(GetValue(it))) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not an array";
+        if (!parent_node.empty()) {
+          (*err) += " in " + parent_node;
+        }
+        (*err) += ".\n";
+      }
+    }
+    return false;
+  }
+
+  ret->clear();
+  auto end = ArrayEnd(GetValue(it));
+  for (auto i = ArrayBegin(GetValue(it)); i != end; ++i) {
+    int numberValue;
+    bool isNumber = GetInt(*i, numberValue);
+    if (!isNumber) {
+      if (required) {
+        if (err) {
+          (*err) += "'" + property + "' property is not an integer type.\n";
+          if (!parent_node.empty()) {
+            (*err) += " in " + parent_node;
+          }
+          (*err) += ".\n";
+        }
+      }
+      return false;
+    }
+    ret->push_back(numberValue);
+  }
+
+  return true;
+}
+
+static bool ParseStringProperty(
+    std::string *ret, std::string *err, const json &o,
+    const std::string &property, bool required,
+    const std::string &parent_node = std::string()) {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing";
+        if (parent_node.empty()) {
+          (*err) += ".\n";
+        } else {
+          (*err) += " in `" + parent_node + "'.\n";
+        }
+      }
+    }
+    return false;
+  }
+
+  std::string strValue;
+  if (!GetString(GetValue(it), strValue)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not a string type.\n";
+      }
+    }
+    return false;
+  }
+
+  if (ret) {
+    (*ret) = std::move(strValue);
+  }
+
+  return true;
+}
+
+static bool ParseStringIntegerProperty(std::map<std::string, int> *ret,
+                                       std::string *err, const json &o,
+                                       const std::string &property,
+                                       bool required,
+                                       const std::string &parent = "") {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        if (!parent.empty()) {
+          (*err) +=
+              "'" + property + "' property is missing in " + parent + ".\n";
+        } else {
+          (*err) += "'" + property + "' property is missing.\n";
+        }
+      }
+    }
+    return false;
+  }
+
+  const json &dict = GetValue(it);
+
+  // Make sure we are dealing with an object / dictionary.
+  if (!IsObject(dict)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not an object.\n";
+      }
+    }
+    return false;
+  }
+
+  ret->clear();
+
+  json_const_iterator dictIt(ObjectBegin(dict));
+  json_const_iterator dictItEnd(ObjectEnd(dict));
+
+  for (; dictIt != dictItEnd; ++dictIt) {
+    int intVal;
+    if (!GetInt(GetValue(dictIt), intVal)) {
+      if (required) {
+        if (err) {
+          (*err) += "'" + property + "' value is not an integer type.\n";
+        }
+      }
+      return false;
+    }
+
+    // Insert into the list.
+    (*ret)[GetKey(dictIt)] = intVal;
+  }
+  return true;
+}
+
+static bool ParseJSONProperty(std::map<std::string, double> *ret,
+                              std::string *err, const json &o,
+                              const std::string &property, bool required) {
+  json_const_iterator it;
+  if (!FindMember(o, property.c_str(), it)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is missing. \n'";
+      }
+    }
+    return false;
+  }
+
+  const json &obj = GetValue(it);
+
+  if (!IsObject(obj)) {
+    if (required) {
+      if (err) {
+        (*err) += "'" + property + "' property is not a JSON object.\n";
+      }
+    }
+    return false;
+  }
+
+  ret->clear();
+
+  json_const_iterator it2(ObjectBegin(obj));
+  json_const_iterator itEnd(ObjectEnd(obj));
+  for (; it2 != itEnd; ++it2) {
+    double numVal;
+    if (GetNumber(GetValue(it2), numVal))
+      ret->emplace(std::string(GetKey(it2)), numVal);
+  }
+
+  return true;
+}
+
+static bool ParseParameterProperty(Parameter *param, std::string *err,
+                                   const json &o, const std::string &prop,
+                                   bool required) {
+  // A parameter value can either be a string or an array of either a boolean or
+  // a number. Booleans of any kind aren't supported here. Granted, it
+  // complicates the Parameter structure and breaks it semantically in the sense
+  // that the client probably works off the assumption that if the string is
+  // empty the vector is used, etc. Would a tagged union work?
+  if (ParseStringProperty(&param->string_value, err, o, prop, false)) {
+    // Found string property.
+    return true;
+  } else if (ParseNumberArrayProperty(&param->number_array, err, o, prop,
+                                      false)) {
+    // Found a number array.
+    return true;
+  } else if (ParseNumberProperty(&param->number_value, err, o, prop, false)) {
+    return param->has_number_value = true;
+  } else if (ParseJSONProperty(&param->json_double_value, err, o, prop,
+                               false)) {
+    return true;
+  } else if (ParseBooleanProperty(&param->bool_value, err, o, prop, false)) {
+    return true;
+  } else {
+    if (required) {
+      if (err) {
+        (*err) += "parameter must be a string or number / number array.\n";
+      }
+    }
+    return false;
+  }
+}
+
+static bool ParseExtensionsProperty(ExtensionMap *ret, std::string *err,
+                                    const json &o) {
+  (void)err;
+
+  json_const_iterator it;
+  if (!FindMember(o, "extensions", it)) {
+    return false;
+  }
+
+  auto &obj = GetValue(it);
+  if (!IsObject(obj)) {
+    return false;
+  }
+  ExtensionMap extensions;
+  json_const_iterator extIt = ObjectBegin(obj);  // it.value().begin();
+  json_const_iterator extEnd = ObjectEnd(obj);
+  for (; extIt != extEnd; ++extIt) {
+    auto &itObj = GetValue(extIt);
+    if (!IsObject(itObj)) continue;
+    std::string key(GetKey(extIt));
+    if (!ParseJsonAsValue(&extensions[key], itObj)) {
+      if (!key.empty()) {
+        // create empty object so that an extension object is still of type
+        // object
+        extensions[key] = Value{Value::Object{}};
+      }
+    }
+  }
+  if (ret) {
+    (*ret) = std::move(extensions);
+  }
+  return true;
+}
+
+static bool ParseAsset(Asset *asset, std::string *err, const json &o,
+                       bool store_original_json_for_extras_and_extensions) {
+  ParseStringProperty(&asset->version, err, o, "version", true, "Asset");
+  ParseStringProperty(&asset->generator, err, o, "generator", false, "Asset");
+  ParseStringProperty(&asset->minVersion, err, o, "minVersion", false, "Asset");
+  ParseStringProperty(&asset->copyright, err, o, "copyright", false, "Asset");
+
+  ParseExtensionsProperty(&asset->extensions, err, o);
+
+  // Unity exporter version is added as extra here
+  ParseExtrasProperty(&(asset->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        asset->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        asset->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseImage(Image *image, const int image_idx, std::string *err,
+                       std::string *warn, const json &o,
+                       bool store_original_json_for_extras_and_extensions,
+                       const std::string &basedir, FsCallbacks *fs,
+                       LoadImageDataFunction *LoadImageData = nullptr,
+                       void *load_image_user_data = nullptr) {
+  // A glTF image must either reference a bufferView or an image uri
+
+  // schema says oneOf [`bufferView`, `uri`]
+  // TODO(syoyo): Check the type of each parameters.
+  json_const_iterator it;
+  bool hasBufferView = FindMember(o, "bufferView", it);
+  bool hasURI = FindMember(o, "uri", it);
+
+  ParseStringProperty(&image->name, err, o, "name", false);
+
+  if (hasBufferView && hasURI) {
+    // Should not both defined.
+    if (err) {
+      (*err) +=
+          "Only one of `bufferView` or `uri` should be defined, but both are "
+          "defined for image[" +
+          std::to_string(image_idx) + "] name = \"" + image->name + "\"\n";
+    }
+    return false;
+  }
+
+  if (!hasBufferView && !hasURI) {
+    if (err) {
+      (*err) += "Neither required `bufferView` nor `uri` defined for image[" +
+                std::to_string(image_idx) + "] name = \"" + image->name +
+                "\"\n";
+    }
+    return false;
+  }
+
+  ParseExtensionsProperty(&image->extensions, err, o);
+  ParseExtrasProperty(&image->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator eit;
+      if (FindMember(o, "extensions", eit)) {
+        image->extensions_json_string = JsonToString(GetValue(eit));
+      }
+    }
+    {
+      json_const_iterator eit;
+      if (FindMember(o, "extras", eit)) {
+        image->extras_json_string = JsonToString(GetValue(eit));
+      }
+    }
+  }
+
+  if (hasBufferView) {
+    int bufferView = -1;
+    if (!ParseIntegerProperty(&bufferView, err, o, "bufferView", true)) {
+      if (err) {
+        (*err) += "Failed to parse `bufferView` for image[" +
+                  std::to_string(image_idx) + "] name = \"" + image->name +
+                  "\"\n";
+      }
+      return false;
+    }
+
+    std::string mime_type;
+    ParseStringProperty(&mime_type, err, o, "mimeType", false);
+
+    int width = 0;
+    ParseIntegerProperty(&width, err, o, "width", false);
+
+    int height = 0;
+    ParseIntegerProperty(&height, err, o, "height", false);
+
+    // Just only save some information here. Loading actual image data from
+    // bufferView is done after this `ParseImage` function.
+    image->bufferView = bufferView;
+    image->mimeType = mime_type;
+    image->width = width;
+    image->height = height;
+
+    return true;
+  }
+
+  // Parse URI & Load image data.
+
+  std::string uri;
+  std::string tmp_err;
+  if (!ParseStringProperty(&uri, &tmp_err, o, "uri", true)) {
+    if (err) {
+      (*err) += "Failed to parse `uri` for image[" + std::to_string(image_idx) +
+                "] name = \"" + image->name + "\".\n";
+    }
+    return false;
+  }
+
+  std::vector<unsigned char> img;
+
+  if (IsDataURI(uri)) {
+    if (!DecodeDataURI(&img, image->mimeType, uri, 0, false)) {
+      if (err) {
+        (*err) += "Failed to decode 'uri' for image[" +
+                  std::to_string(image_idx) + "] name = [" + image->name +
+                  "]\n";
+      }
+      return false;
+    }
+  } else {
+    // Assume external file
+    // Keep texture path (for textures that cannot be decoded)
+    image->uri = uri;
+#ifdef TINYGLTF_NO_EXTERNAL_IMAGE
+    return true;
+#endif
+    std::string decoded_uri = dlib::urldecode(uri);
+    if (!LoadExternalFile(&img, err, warn, decoded_uri, basedir,
+                          /* required */ false, /* required bytes */ 0,
+                          /* checksize */ false, fs)) {
+      if (warn) {
+        (*warn) += "Failed to load external 'uri' for image[" +
+                   std::to_string(image_idx) + "] name = [" + image->name +
+                   "]\n";
+      }
+      // If the image cannot be loaded, keep uri as image->uri.
+      return true;
+    }
+
+    if (img.empty()) {
+      if (warn) {
+        (*warn) += "Image data is empty for image[" +
+                   std::to_string(image_idx) + "] name = [" + image->name +
+                   "] \n";
+      }
+      return false;
+    }
+  }
+
+  if (*LoadImageData == nullptr) {
+    if (err) {
+      (*err) += "No LoadImageData callback specified.\n";
+    }
+    return false;
+  }
+  return (*LoadImageData)(image, image_idx, err, warn, 0, 0, &img.at(0),
+                          static_cast<int>(img.size()), load_image_user_data);
+}
+
+static bool ParseTexture(Texture *texture, std::string *err, const json &o,
+                         bool store_original_json_for_extras_and_extensions,
+                         const std::string &basedir) {
+  (void)basedir;
+  int sampler = -1;
+  int source = -1;
+  ParseIntegerProperty(&sampler, err, o, "sampler", false);
+
+  ParseIntegerProperty(&source, err, o, "source", false);
+
+  texture->sampler = sampler;
+  texture->source = source;
+
+  ParseExtensionsProperty(&texture->extensions, err, o);
+  ParseExtrasProperty(&texture->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        texture->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        texture->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  ParseStringProperty(&texture->name, err, o, "name", false);
+
+  return true;
+}
+
+static bool ParseTextureInfo(
+    TextureInfo *texinfo, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  if (texinfo == nullptr) {
+    return false;
+  }
+
+  if (!ParseIntegerProperty(&texinfo->index, err, o, "index",
+                            /* required */ true, "TextureInfo")) {
+    return false;
+  }
+
+  ParseIntegerProperty(&texinfo->texCoord, err, o, "texCoord", false);
+
+  ParseExtensionsProperty(&texinfo->extensions, err, o);
+  ParseExtrasProperty(&texinfo->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        texinfo->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        texinfo->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseNormalTextureInfo(
+    NormalTextureInfo *texinfo, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  if (texinfo == nullptr) {
+    return false;
+  }
+
+  if (!ParseIntegerProperty(&texinfo->index, err, o, "index",
+                            /* required */ true, "NormalTextureInfo")) {
+    return false;
+  }
+
+  ParseIntegerProperty(&texinfo->texCoord, err, o, "texCoord", false);
+  ParseNumberProperty(&texinfo->scale, err, o, "scale", false);
+
+  ParseExtensionsProperty(&texinfo->extensions, err, o);
+  ParseExtrasProperty(&texinfo->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        texinfo->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        texinfo->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseOcclusionTextureInfo(
+    OcclusionTextureInfo *texinfo, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  if (texinfo == nullptr) {
+    return false;
+  }
+
+  if (!ParseIntegerProperty(&texinfo->index, err, o, "index",
+                            /* required */ true, "NormalTextureInfo")) {
+    return false;
+  }
+
+  ParseIntegerProperty(&texinfo->texCoord, err, o, "texCoord", false);
+  ParseNumberProperty(&texinfo->strength, err, o, "strength", false);
+
+  ParseExtensionsProperty(&texinfo->extensions, err, o);
+  ParseExtrasProperty(&texinfo->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        texinfo->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        texinfo->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseBuffer(Buffer *buffer, std::string *err, const json &o,
+                        bool store_original_json_for_extras_and_extensions,
+                        FsCallbacks *fs, const std::string &basedir,
+                        bool is_binary = false,
+                        const unsigned char *bin_data = nullptr,
+                        size_t bin_size = 0) {
+  size_t byteLength;
+  if (!ParseUnsignedProperty(&byteLength, err, o, "byteLength", true,
+                             "Buffer")) {
+    return false;
+  }
+
+  // In glTF 2.0, uri is not mandatory anymore
+  buffer->uri.clear();
+  ParseStringProperty(&buffer->uri, err, o, "uri", false, "Buffer");
+
+  // having an empty uri for a non embedded image should not be valid
+  if (!is_binary && buffer->uri.empty()) {
+    if (err) {
+      (*err) += "'uri' is missing from non binary glTF file buffer.\n";
+    }
+  }
+
+  json_const_iterator type;
+  if (FindMember(o, "type", type)) {
+    std::string typeStr;
+    if (GetString(GetValue(type), typeStr)) {
+      if (typeStr.compare("arraybuffer") == 0) {
+        // buffer.type = "arraybuffer";
+      }
+    }
+  }
+
+  if (is_binary) {
+    // Still binary glTF accepts external dataURI.
+    if (!buffer->uri.empty()) {
+      // First try embedded data URI.
+      if (IsDataURI(buffer->uri)) {
+        std::string mime_type;
+        if (!DecodeDataURI(&buffer->data, mime_type, buffer->uri, byteLength,
+                           true)) {
+          if (err) {
+            (*err) +=
+                "Failed to decode 'uri' : " + buffer->uri + " in Buffer\n";
+          }
+          return false;
+        }
+      } else {
+        // External .bin file.
+        std::string decoded_uri = dlib::urldecode(buffer->uri);
+        if (!LoadExternalFile(&buffer->data, err, /* warn */ nullptr,
+                              decoded_uri, basedir, /* required */ true,
+                              byteLength, /* checkSize */ true, fs)) {
+          return false;
+        }
+      }
+    } else {
+      // load data from (embedded) binary data
+
+      if ((bin_size == 0) || (bin_data == nullptr)) {
+        if (err) {
+          (*err) += "Invalid binary data in `Buffer'.\n";
+        }
+        return false;
+      }
+
+      if (byteLength > bin_size) {
+        if (err) {
+          std::stringstream ss;
+          ss << "Invalid `byteLength'. Must be equal or less than binary size: "
+                "`byteLength' = "
+             << byteLength << ", binary size = " << bin_size << std::endl;
+          (*err) += ss.str();
+        }
+        return false;
+      }
+
+      // Read buffer data
+      buffer->data.resize(static_cast<size_t>(byteLength));
+      memcpy(&(buffer->data.at(0)), bin_data, static_cast<size_t>(byteLength));
+    }
+
+  } else {
+    if (IsDataURI(buffer->uri)) {
+      std::string mime_type;
+      if (!DecodeDataURI(&buffer->data, mime_type, buffer->uri, byteLength,
+                         true)) {
+        if (err) {
+          (*err) += "Failed to decode 'uri' : " + buffer->uri + " in Buffer\n";
+        }
+        return false;
+      }
+    } else {
+      // Assume external .bin file.
+      std::string decoded_uri = dlib::urldecode(buffer->uri);
+      if (!LoadExternalFile(&buffer->data, err, /* warn */ nullptr, decoded_uri,
+                            basedir, /* required */ true, byteLength,
+                            /* checkSize */ true, fs)) {
+        return false;
+      }
+    }
+  }
+
+  ParseStringProperty(&buffer->name, err, o, "name", false);
+
+  ParseExtensionsProperty(&buffer->extensions, err, o);
+  ParseExtrasProperty(&buffer->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        buffer->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        buffer->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseBufferView(
+    BufferView *bufferView, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  int buffer = -1;
+  if (!ParseIntegerProperty(&buffer, err, o, "buffer", true, "BufferView")) {
+    return false;
+  }
+
+  size_t byteOffset = 0;
+  ParseUnsignedProperty(&byteOffset, err, o, "byteOffset", false);
+
+  size_t byteLength = 1;
+  if (!ParseUnsignedProperty(&byteLength, err, o, "byteLength", true,
+                             "BufferView")) {
+    return false;
+  }
+
+  size_t byteStride = 0;
+  if (!ParseUnsignedProperty(&byteStride, err, o, "byteStride", false)) {
+    // Spec says: When byteStride of referenced bufferView is not defined, it
+    // means that accessor elements are tightly packed, i.e., effective stride
+    // equals the size of the element.
+    // We cannot determine the actual byteStride until Accessor are parsed, thus
+    // set 0(= tightly packed) here(as done in OpenGL's VertexAttribPoiner)
+    byteStride = 0;
+  }
+
+  if ((byteStride > 252) || ((byteStride % 4) != 0)) {
+    if (err) {
+      std::stringstream ss;
+      ss << "Invalid `byteStride' value. `byteStride' must be the multiple of "
+            "4 : "
+         << byteStride << std::endl;
+
+      (*err) += ss.str();
+    }
+    return false;
+  }
+
+  int target = 0;
+  ParseIntegerProperty(&target, err, o, "target", false);
+  if ((target == TINYGLTF_TARGET_ARRAY_BUFFER) ||
+      (target == TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER)) {
+    // OK
+  } else {
+    target = 0;
+  }
+  bufferView->target = target;
+
+  ParseStringProperty(&bufferView->name, err, o, "name", false);
+
+  ParseExtensionsProperty(&bufferView->extensions, err, o);
+  ParseExtrasProperty(&bufferView->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        bufferView->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        bufferView->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  bufferView->buffer = buffer;
+  bufferView->byteOffset = byteOffset;
+  bufferView->byteLength = byteLength;
+  bufferView->byteStride = byteStride;
+  return true;
+}
+
+static bool ParseSparseAccessor(Accessor *accessor, std::string *err,
+                                const json &o) {
+  accessor->sparse.isSparse = true;
+
+  int count = 0;
+  ParseIntegerProperty(&count, err, o, "count", true);
+
+  json_const_iterator indices_iterator;
+  json_const_iterator values_iterator;
+  if (!FindMember(o, "indices", indices_iterator)) {
+    (*err) = "the sparse object of this accessor doesn't have indices";
+    return false;
+  }
+
+  if (!FindMember(o, "values", values_iterator)) {
+    (*err) = "the sparse object ob ths accessor doesn't have values";
+    return false;
+  }
+
+  const json &indices_obj = GetValue(indices_iterator);
+  const json &values_obj = GetValue(values_iterator);
+
+  int indices_buffer_view = 0, indices_byte_offset = 0, component_type = 0;
+  ParseIntegerProperty(&indices_buffer_view, err, indices_obj, "bufferView",
+                       true);
+  ParseIntegerProperty(&indices_byte_offset, err, indices_obj, "byteOffset",
+                       true);
+  ParseIntegerProperty(&component_type, err, indices_obj, "componentType",
+                       true);
+
+  int values_buffer_view = 0, values_byte_offset = 0;
+  ParseIntegerProperty(&values_buffer_view, err, values_obj, "bufferView",
+                       true);
+  ParseIntegerProperty(&values_byte_offset, err, values_obj, "byteOffset",
+                       true);
+
+  accessor->sparse.count = count;
+  accessor->sparse.indices.bufferView = indices_buffer_view;
+  accessor->sparse.indices.byteOffset = indices_byte_offset;
+  accessor->sparse.indices.componentType = component_type;
+  accessor->sparse.values.bufferView = values_buffer_view;
+  accessor->sparse.values.byteOffset = values_byte_offset;
+
+  // todo check theses values
+
+  return true;
+}
+
+static bool ParseAccessor(Accessor *accessor, std::string *err, const json &o,
+                          bool store_original_json_for_extras_and_extensions) {
+  int bufferView = -1;
+  ParseIntegerProperty(&bufferView, err, o, "bufferView", false, "Accessor");
+
+  size_t byteOffset = 0;
+  ParseUnsignedProperty(&byteOffset, err, o, "byteOffset", false, "Accessor");
+
+  bool normalized = false;
+  ParseBooleanProperty(&normalized, err, o, "normalized", false, "Accessor");
+
+  size_t componentType = 0;
+  if (!ParseUnsignedProperty(&componentType, err, o, "componentType", true,
+                             "Accessor")) {
+    return false;
+  }
+
+  size_t count = 0;
+  if (!ParseUnsignedProperty(&count, err, o, "count", true, "Accessor")) {
+    return false;
+  }
+
+  std::string type;
+  if (!ParseStringProperty(&type, err, o, "type", true, "Accessor")) {
+    return false;
+  }
+
+  if (type.compare("SCALAR") == 0) {
+    accessor->type = TINYGLTF_TYPE_SCALAR;
+  } else if (type.compare("VEC2") == 0) {
+    accessor->type = TINYGLTF_TYPE_VEC2;
+  } else if (type.compare("VEC3") == 0) {
+    accessor->type = TINYGLTF_TYPE_VEC3;
+  } else if (type.compare("VEC4") == 0) {
+    accessor->type = TINYGLTF_TYPE_VEC4;
+  } else if (type.compare("MAT2") == 0) {
+    accessor->type = TINYGLTF_TYPE_MAT2;
+  } else if (type.compare("MAT3") == 0) {
+    accessor->type = TINYGLTF_TYPE_MAT3;
+  } else if (type.compare("MAT4") == 0) {
+    accessor->type = TINYGLTF_TYPE_MAT4;
+  } else {
+    std::stringstream ss;
+    ss << "Unsupported `type` for accessor object. Got \"" << type << "\"\n";
+    if (err) {
+      (*err) += ss.str();
+    }
+    return false;
+  }
+
+  ParseStringProperty(&accessor->name, err, o, "name", false);
+
+  accessor->minValues.clear();
+  accessor->maxValues.clear();
+  ParseNumberArrayProperty(&accessor->minValues, err, o, "min", false,
+                           "Accessor");
+
+  ParseNumberArrayProperty(&accessor->maxValues, err, o, "max", false,
+                           "Accessor");
+
+  accessor->count = count;
+  accessor->bufferView = bufferView;
+  accessor->byteOffset = byteOffset;
+  accessor->normalized = normalized;
+  {
+    if (componentType >= TINYGLTF_COMPONENT_TYPE_BYTE &&
+        componentType <= TINYGLTF_COMPONENT_TYPE_DOUBLE) {
+      // OK
+      accessor->componentType = int(componentType);
+    } else {
+      std::stringstream ss;
+      ss << "Invalid `componentType` in accessor. Got " << componentType
+         << "\n";
+      if (err) {
+        (*err) += ss.str();
+      }
+      return false;
+    }
+  }
+
+  ParseExtensionsProperty(&(accessor->extensions), err, o);
+  ParseExtrasProperty(&(accessor->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        accessor->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        accessor->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  // check if accessor has a "sparse" object:
+  json_const_iterator iterator;
+  if (FindMember(o, "sparse", iterator)) {
+    // here this accessor has a "sparse" subobject
+    return ParseSparseAccessor(accessor, err, GetValue(iterator));
+  }
+
+  return true;
+}
+
+#ifdef TINYGLTF_ENABLE_DRACO
+
+static void DecodeIndexBuffer(draco::Mesh *mesh, size_t componentSize,
+                              std::vector<uint8_t> &outBuffer) {
+  if (componentSize == 4) {
+    assert(sizeof(mesh->face(draco::FaceIndex(0))[0]) == componentSize);
+    memcpy(outBuffer.data(), &mesh->face(draco::FaceIndex(0))[0],
+           outBuffer.size());
+  } else {
+    size_t faceStride = componentSize * 3;
+    for (draco::FaceIndex f(0); f < mesh->num_faces(); ++f) {
+      const draco::Mesh::Face &face = mesh->face(f);
+      if (componentSize == 2) {
+        uint16_t indices[3] = {(uint16_t)face[0].value(),
+                               (uint16_t)face[1].value(),
+                               (uint16_t)face[2].value()};
+        memcpy(outBuffer.data() + f.value() * faceStride, &indices[0],
+               faceStride);
+      } else {
+        uint8_t indices[3] = {(uint8_t)face[0].value(),
+                              (uint8_t)face[1].value(),
+                              (uint8_t)face[2].value()};
+        memcpy(outBuffer.data() + f.value() * faceStride, &indices[0],
+               faceStride);
+      }
+    }
+  }
+}
+
+template <typename T>
+static bool GetAttributeForAllPoints(draco::Mesh *mesh,
+                                     const draco::PointAttribute *pAttribute,
+                                     std::vector<uint8_t> &outBuffer) {
+  size_t byteOffset = 0;
+  T values[4] = {0, 0, 0, 0};
+  for (draco::PointIndex i(0); i < mesh->num_points(); ++i) {
+    const draco::AttributeValueIndex val_index = pAttribute->mapped_index(i);
+    if (!pAttribute->ConvertValue<T>(val_index, pAttribute->num_components(),
+                                     values))
+      return false;
+
+    memcpy(outBuffer.data() + byteOffset, &values[0],
+           sizeof(T) * pAttribute->num_components());
+    byteOffset += sizeof(T) * pAttribute->num_components();
+  }
+
+  return true;
+}
+
+static bool GetAttributeForAllPoints(uint32_t componentType, draco::Mesh *mesh,
+                                     const draco::PointAttribute *pAttribute,
+                                     std::vector<uint8_t> &outBuffer) {
+  bool decodeResult = false;
+  switch (componentType) {
+    case TINYGLTF_COMPONENT_TYPE_UNSIGNED_BYTE:
+      decodeResult =
+          GetAttributeForAllPoints<uint8_t>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_BYTE:
+      decodeResult =
+          GetAttributeForAllPoints<int8_t>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_UNSIGNED_SHORT:
+      decodeResult =
+          GetAttributeForAllPoints<uint16_t>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_SHORT:
+      decodeResult =
+          GetAttributeForAllPoints<int16_t>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_INT:
+      decodeResult =
+          GetAttributeForAllPoints<int32_t>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_UNSIGNED_INT:
+      decodeResult =
+          GetAttributeForAllPoints<uint32_t>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_FLOAT:
+      decodeResult =
+          GetAttributeForAllPoints<float>(mesh, pAttribute, outBuffer);
+      break;
+    case TINYGLTF_COMPONENT_TYPE_DOUBLE:
+      decodeResult =
+          GetAttributeForAllPoints<double>(mesh, pAttribute, outBuffer);
+      break;
+    default:
+      return false;
+  }
+
+  return decodeResult;
+}
+
+static bool ParseDracoExtension(Primitive *primitive, Model *model,
+                                std::string *err,
+                                const Value &dracoExtensionValue) {
+  auto bufferViewValue = dracoExtensionValue.Get("bufferView");
+  if (!bufferViewValue.IsInt()) return false;
+  auto attributesValue = dracoExtensionValue.Get("attributes");
+  if (!attributesValue.IsObject()) return false;
+
+  auto attributesObject = attributesValue.Get<Value::Object>();
+  int bufferView = bufferViewValue.Get<int>();
+
+  BufferView &view = model->bufferViews[bufferView];
+  Buffer &buffer = model->buffers[view.buffer];
+  // BufferView has already been decoded
+  if (view.dracoDecoded) return true;
+  view.dracoDecoded = true;
+
+  const char *bufferViewData =
+      reinterpret_cast<const char *>(buffer.data.data() + view.byteOffset);
+  size_t bufferViewSize = view.byteLength;
+
+  // decode draco
+  draco::DecoderBuffer decoderBuffer;
+  decoderBuffer.Init(bufferViewData, bufferViewSize);
+  draco::Decoder decoder;
+  auto decodeResult = decoder.DecodeMeshFromBuffer(&decoderBuffer);
+  if (!decodeResult.ok()) {
+    return false;
+  }
+  const std::unique_ptr<draco::Mesh> &mesh = decodeResult.value();
+
+  // create new bufferView for indices
+  if (primitive->indices >= 0) {
+    int32_t componentSize = GetComponentSizeInBytes(
+        model->accessors[primitive->indices].componentType);
+    Buffer decodedIndexBuffer;
+    decodedIndexBuffer.data.resize(mesh->num_faces() * 3 * componentSize);
+
+    DecodeIndexBuffer(mesh.get(), componentSize, decodedIndexBuffer.data);
+
+    model->buffers.emplace_back(std::move(decodedIndexBuffer));
+
+    BufferView decodedIndexBufferView;
+    decodedIndexBufferView.buffer = int(model->buffers.size() - 1);
+    decodedIndexBufferView.byteLength =
+        int(mesh->num_faces() * 3 * componentSize);
+    decodedIndexBufferView.byteOffset = 0;
+    decodedIndexBufferView.byteStride = 0;
+    decodedIndexBufferView.target = TINYGLTF_TARGET_ARRAY_BUFFER;
+    model->bufferViews.emplace_back(std::move(decodedIndexBufferView));
+
+    model->accessors[primitive->indices].bufferView =
+        int(model->bufferViews.size() - 1);
+    model->accessors[primitive->indices].count = int(mesh->num_faces() * 3);
+  }
+
+  for (const auto &attribute : attributesObject) {
+    if (!attribute.second.IsInt()) return false;
+    auto primitiveAttribute = primitive->attributes.find(attribute.first);
+    if (primitiveAttribute == primitive->attributes.end()) return false;
+
+    int dracoAttributeIndex = attribute.second.Get<int>();
+    const auto pAttribute = mesh->GetAttributeByUniqueId(dracoAttributeIndex);
+    const auto pBuffer = pAttribute->buffer();
+    const auto componentType =
+        model->accessors[primitiveAttribute->second].componentType;
+
+    // Create a new buffer for this decoded buffer
+    Buffer decodedBuffer;
+    size_t bufferSize = mesh->num_points() * pAttribute->num_components() *
+                        GetComponentSizeInBytes(componentType);
+    decodedBuffer.data.resize(bufferSize);
+
+    if (!GetAttributeForAllPoints(componentType, mesh.get(), pAttribute,
+                                  decodedBuffer.data))
+      return false;
+
+    model->buffers.emplace_back(std::move(decodedBuffer));
+
+    BufferView decodedBufferView;
+    decodedBufferView.buffer = int(model->buffers.size() - 1);
+    decodedBufferView.byteLength = bufferSize;
+    decodedBufferView.byteOffset = pAttribute->byte_offset();
+    decodedBufferView.byteStride = pAttribute->byte_stride();
+    decodedBufferView.target = primitive->indices >= 0
+                                   ? TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER
+                                   : TINYGLTF_TARGET_ARRAY_BUFFER;
+    model->bufferViews.emplace_back(std::move(decodedBufferView));
+
+    model->accessors[primitiveAttribute->second].bufferView =
+        int(model->bufferViews.size() - 1);
+    model->accessors[primitiveAttribute->second].count =
+        int(mesh->num_points());
+  }
+
+  return true;
+}
+#endif
+
+static bool ParsePrimitive(Primitive *primitive, Model *model, std::string *err,
+                           const json &o,
+                           bool store_original_json_for_extras_and_extensions) {
+  int material = -1;
+  ParseIntegerProperty(&material, err, o, "material", false);
+  primitive->material = material;
+
+  int mode = TINYGLTF_MODE_TRIANGLES;
+  ParseIntegerProperty(&mode, err, o, "mode", false);
+  primitive->mode = mode;  // Why only triangled were supported ?
+
+  int indices = -1;
+  ParseIntegerProperty(&indices, err, o, "indices", false);
+  primitive->indices = indices;
+  if (!ParseStringIntegerProperty(&primitive->attributes, err, o, "attributes",
+                                  true, "Primitive")) {
+    return false;
+  }
+
+  // Look for morph targets
+  json_const_iterator targetsObject;
+  if (FindMember(o, "targets", targetsObject) &&
+      IsArray(GetValue(targetsObject))) {
+    auto targetsObjectEnd = ArrayEnd(GetValue(targetsObject));
+    for (json_const_array_iterator i = ArrayBegin(GetValue(targetsObject));
+         i != targetsObjectEnd; ++i) {
+      std::map<std::string, int> targetAttribues;
+
+      const json &dict = *i;
+      if (IsObject(dict)) {
+        json_const_iterator dictIt(ObjectBegin(dict));
+        json_const_iterator dictItEnd(ObjectEnd(dict));
+
+        for (; dictIt != dictItEnd; ++dictIt) {
+          int iVal;
+          if (GetInt(GetValue(dictIt), iVal))
+            targetAttribues[GetKey(dictIt)] = iVal;
+        }
+        primitive->targets.emplace_back(std::move(targetAttribues));
+      }
+    }
+  }
+
+  ParseExtrasProperty(&(primitive->extras), o);
+  ParseExtensionsProperty(&primitive->extensions, err, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        primitive->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        primitive->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+#ifdef TINYGLTF_ENABLE_DRACO
+  auto dracoExtension =
+      primitive->extensions.find("KHR_draco_mesh_compression");
+  if (dracoExtension != primitive->extensions.end()) {
+    ParseDracoExtension(primitive, model, err, dracoExtension->second);
+  }
+#else
+  (void)model;
+#endif
+
+  return true;
+}
+
+static bool ParseMesh(Mesh *mesh, Model *model, std::string *err, const json &o,
+                      bool store_original_json_for_extras_and_extensions) {
+  ParseStringProperty(&mesh->name, err, o, "name", false);
+
+  mesh->primitives.clear();
+  json_const_iterator primObject;
+  if (FindMember(o, "primitives", primObject) &&
+      IsArray(GetValue(primObject))) {
+    json_const_array_iterator primEnd = ArrayEnd(GetValue(primObject));
+    for (json_const_array_iterator i = ArrayBegin(GetValue(primObject));
+         i != primEnd; ++i) {
+      Primitive primitive;
+      if (ParsePrimitive(&primitive, model, err, *i,
+                         store_original_json_for_extras_and_extensions)) {
+        // Only add the primitive if the parsing succeeds.
+        mesh->primitives.emplace_back(std::move(primitive));
+      }
+    }
+  }
+
+  // Should probably check if has targets and if dimensions fit
+  ParseNumberArrayProperty(&mesh->weights, err, o, "weights", false);
+
+  ParseExtensionsProperty(&mesh->extensions, err, o);
+  ParseExtrasProperty(&(mesh->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        mesh->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        mesh->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseNode(Node *node, std::string *err, const json &o,
+                      bool store_original_json_for_extras_and_extensions) {
+  ParseStringProperty(&node->name, err, o, "name", false);
+
+  int skin = -1;
+  ParseIntegerProperty(&skin, err, o, "skin", false);
+  node->skin = skin;
+
+  // Matrix and T/R/S are exclusive
+  if (!ParseNumberArrayProperty(&node->matrix, err, o, "matrix", false)) {
+    ParseNumberArrayProperty(&node->rotation, err, o, "rotation", false);
+    ParseNumberArrayProperty(&node->scale, err, o, "scale", false);
+    ParseNumberArrayProperty(&node->translation, err, o, "translation", false);
+  }
+
+  int camera = -1;
+  ParseIntegerProperty(&camera, err, o, "camera", false);
+  node->camera = camera;
+
+  int mesh = -1;
+  ParseIntegerProperty(&mesh, err, o, "mesh", false);
+  node->mesh = mesh;
+
+  node->children.clear();
+  ParseIntegerArrayProperty(&node->children, err, o, "children", false);
+
+  ParseNumberArrayProperty(&node->weights, err, o, "weights", false);
+
+  ParseExtensionsProperty(&node->extensions, err, o);
+  ParseExtrasProperty(&(node->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        node->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        node->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParsePbrMetallicRoughness(
+    PbrMetallicRoughness *pbr, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  if (pbr == nullptr) {
+    return false;
+  }
+
+  std::vector<double> baseColorFactor;
+  if (ParseNumberArrayProperty(&baseColorFactor, err, o, "baseColorFactor",
+                               /* required */ false)) {
+    if (baseColorFactor.size() != 4) {
+      if (err) {
+        (*err) +=
+            "Array length of `baseColorFactor` parameter in "
+            "pbrMetallicRoughness must be 4, but got " +
+            std::to_string(baseColorFactor.size()) + "\n";
+      }
+      return false;
+    }
+    pbr->baseColorFactor = baseColorFactor;
+  }
+
+  {
+    json_const_iterator it;
+    if (FindMember(o, "baseColorTexture", it)) {
+      ParseTextureInfo(&pbr->baseColorTexture, err, GetValue(it),
+                       store_original_json_for_extras_and_extensions);
+    }
+  }
+
+  {
+    json_const_iterator it;
+    if (FindMember(o, "metallicRoughnessTexture", it)) {
+      ParseTextureInfo(&pbr->metallicRoughnessTexture, err, GetValue(it),
+                       store_original_json_for_extras_and_extensions);
+    }
+  }
+
+  ParseNumberProperty(&pbr->metallicFactor, err, o, "metallicFactor", false);
+  ParseNumberProperty(&pbr->roughnessFactor, err, o, "roughnessFactor", false);
+
+  ParseExtensionsProperty(&pbr->extensions, err, o);
+  ParseExtrasProperty(&pbr->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        pbr->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        pbr->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseMaterial(Material *material, std::string *err, const json &o,
+                          bool store_original_json_for_extras_and_extensions) {
+  ParseStringProperty(&material->name, err, o, "name", /* required */ false);
+
+  if (ParseNumberArrayProperty(&material->emissiveFactor, err, o,
+                               "emissiveFactor",
+                               /* required */ false)) {
+    if (material->emissiveFactor.size() != 3) {
+      if (err) {
+        (*err) +=
+            "Array length of `emissiveFactor` parameter in "
+            "material must be 3, but got " +
+            std::to_string(material->emissiveFactor.size()) + "\n";
+      }
+      return false;
+    }
+  } else {
+    // fill with default values
+    material->emissiveFactor = {0.0, 0.0, 0.0};
+  }
+
+  ParseStringProperty(&material->alphaMode, err, o, "alphaMode",
+                      /* required */ false);
+  ParseNumberProperty(&material->alphaCutoff, err, o, "alphaCutoff",
+                      /* required */ false);
+  ParseBooleanProperty(&material->doubleSided, err, o, "doubleSided",
+                       /* required */ false);
+
+  {
+    json_const_iterator it;
+    if (FindMember(o, "pbrMetallicRoughness", it)) {
+      ParsePbrMetallicRoughness(&material->pbrMetallicRoughness, err,
+                                GetValue(it),
+                                store_original_json_for_extras_and_extensions);
+    }
+  }
+
+  {
+    json_const_iterator it;
+    if (FindMember(o, "normalTexture", it)) {
+      ParseNormalTextureInfo(&material->normalTexture, err, GetValue(it),
+                             store_original_json_for_extras_and_extensions);
+    }
+  }
+
+  {
+    json_const_iterator it;
+    if (FindMember(o, "occlusionTexture", it)) {
+      ParseOcclusionTextureInfo(&material->occlusionTexture, err, GetValue(it),
+                                store_original_json_for_extras_and_extensions);
+    }
+  }
+
+  {
+    json_const_iterator it;
+    if (FindMember(o, "emissiveTexture", it)) {
+      ParseTextureInfo(&material->emissiveTexture, err, GetValue(it),
+                       store_original_json_for_extras_and_extensions);
+    }
+  }
+
+  // Old code path. For backward compatibility, we still store material values
+  // as Parameter. This will create duplicated information for
+  // example(pbrMetallicRoughness), but should be neglible in terms of memory
+  // consumption.
+  // TODO(syoyo): Remove in the next major release.
+  material->values.clear();
+  material->additionalValues.clear();
+
+  json_const_iterator it(ObjectBegin(o));
+  json_const_iterator itEnd(ObjectEnd(o));
+
+  for (; it != itEnd; ++it) {
+    std::string key(GetKey(it));
+    if (key == "pbrMetallicRoughness") {
+      if (IsObject(GetValue(it))) {
+        const json &values_object = GetValue(it);
+
+        json_const_iterator itVal(ObjectBegin(values_object));
+        json_const_iterator itValEnd(ObjectEnd(values_object));
+
+        for (; itVal != itValEnd; ++itVal) {
+          Parameter param;
+          if (ParseParameterProperty(&param, err, values_object, GetKey(itVal),
+                                     false)) {
+            material->values.emplace(GetKey(itVal), std::move(param));
+          }
+        }
+      }
+    } else if (key == "extensions" || key == "extras") {
+      // done later, skip, otherwise poorly parsed contents will be saved in the
+      // parametermap and serialized again later
+    } else {
+      Parameter param;
+      if (ParseParameterProperty(&param, err, o, key, false)) {
+        // names of materials have already been parsed. Putting it in this map
+        // doesn't correctly reflext the glTF specification
+        if (key != "name")
+          material->additionalValues.emplace(std::move(key), std::move(param));
+      }
+    }
+  }
+
+  material->extensions.clear();
+  ParseExtensionsProperty(&material->extensions, err, o);
+  ParseExtrasProperty(&(material->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator eit;
+      if (FindMember(o, "extensions", eit)) {
+        material->extensions_json_string = JsonToString(GetValue(eit));
+      }
+    }
+    {
+      json_const_iterator eit;
+      if (FindMember(o, "extras", eit)) {
+        material->extras_json_string = JsonToString(GetValue(eit));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseAnimationChannel(
+    AnimationChannel *channel, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  int samplerIndex = -1;
+  int targetIndex = -1;
+  if (!ParseIntegerProperty(&samplerIndex, err, o, "sampler", true,
+                            "AnimationChannel")) {
+    if (err) {
+      (*err) += "`sampler` field is missing in animation channels\n";
+    }
+    return false;
+  }
+
+  json_const_iterator targetIt;
+  if (FindMember(o, "target", targetIt) && IsObject(GetValue(targetIt))) {
+    const json &target_object = GetValue(targetIt);
+
+    if (!ParseIntegerProperty(&targetIndex, err, target_object, "node", true)) {
+      if (err) {
+        (*err) += "`node` field is missing in animation.channels.target\n";
+      }
+      return false;
+    }
+
+    if (!ParseStringProperty(&channel->target_path, err, target_object, "path",
+                             true)) {
+      if (err) {
+        (*err) += "`path` field is missing in animation.channels.target\n";
+      }
+      return false;
+    }
+    ParseExtensionsProperty(&channel->target_extensions, err, target_object);
+    if (store_original_json_for_extras_and_extensions) {
+      json_const_iterator it;
+      if (FindMember(target_object, "extensions", it)) {
+        channel->target_extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  channel->sampler = samplerIndex;
+  channel->target_node = targetIndex;
+
+  ParseExtensionsProperty(&channel->extensions, err, o);
+  ParseExtrasProperty(&(channel->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        channel->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        channel->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseAnimation(Animation *animation, std::string *err,
+                           const json &o,
+                           bool store_original_json_for_extras_and_extensions) {
+  {
+    json_const_iterator channelsIt;
+    if (FindMember(o, "channels", channelsIt) &&
+        IsArray(GetValue(channelsIt))) {
+      json_const_array_iterator channelEnd = ArrayEnd(GetValue(channelsIt));
+      for (json_const_array_iterator i = ArrayBegin(GetValue(channelsIt));
+           i != channelEnd; ++i) {
+        AnimationChannel channel;
+        if (ParseAnimationChannel(
+                &channel, err, *i,
+                store_original_json_for_extras_and_extensions)) {
+          // Only add the channel if the parsing succeeds.
+          animation->channels.emplace_back(std::move(channel));
+        }
+      }
+    }
+  }
+
+  {
+    json_const_iterator samplerIt;
+    if (FindMember(o, "samplers", samplerIt) && IsArray(GetValue(samplerIt))) {
+      const json &sampler_array = GetValue(samplerIt);
+
+      json_const_array_iterator it = ArrayBegin(sampler_array);
+      json_const_array_iterator itEnd = ArrayEnd(sampler_array);
+
+      for (; it != itEnd; ++it) {
+        const json &s = *it;
+
+        AnimationSampler sampler;
+        int inputIndex = -1;
+        int outputIndex = -1;
+        if (!ParseIntegerProperty(&inputIndex, err, s, "input", true)) {
+          if (err) {
+            (*err) += "`input` field is missing in animation.sampler\n";
+          }
+          return false;
+        }
+        ParseStringProperty(&sampler.interpolation, err, s, "interpolation",
+                            false);
+        if (!ParseIntegerProperty(&outputIndex, err, s, "output", true)) {
+          if (err) {
+            (*err) += "`output` field is missing in animation.sampler\n";
+          }
+          return false;
+        }
+        sampler.input = inputIndex;
+        sampler.output = outputIndex;
+        ParseExtensionsProperty(&(sampler.extensions), err, o);
+        ParseExtrasProperty(&(sampler.extras), s);
+
+        if (store_original_json_for_extras_and_extensions) {
+          {
+            json_const_iterator eit;
+            if (FindMember(o, "extensions", eit)) {
+              sampler.extensions_json_string = JsonToString(GetValue(eit));
+            }
+          }
+          {
+            json_const_iterator eit;
+            if (FindMember(o, "extras", eit)) {
+              sampler.extras_json_string = JsonToString(GetValue(eit));
+            }
+          }
+        }
+
+        animation->samplers.emplace_back(std::move(sampler));
+      }
+    }
+  }
+
+  ParseStringProperty(&animation->name, err, o, "name", false);
+
+  ParseExtensionsProperty(&animation->extensions, err, o);
+  ParseExtrasProperty(&(animation->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        animation->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        animation->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseSampler(Sampler *sampler, std::string *err, const json &o,
+                         bool store_original_json_for_extras_and_extensions) {
+  ParseStringProperty(&sampler->name, err, o, "name", false);
+
+  int minFilter = -1;
+  int magFilter = -1;
+  int wrapS = TINYGLTF_TEXTURE_WRAP_REPEAT;
+  int wrapT = TINYGLTF_TEXTURE_WRAP_REPEAT;
+  int wrapR = TINYGLTF_TEXTURE_WRAP_REPEAT;
+  ParseIntegerProperty(&minFilter, err, o, "minFilter", false);
+  ParseIntegerProperty(&magFilter, err, o, "magFilter", false);
+  ParseIntegerProperty(&wrapS, err, o, "wrapS", false);
+  ParseIntegerProperty(&wrapT, err, o, "wrapT", false);
+  ParseIntegerProperty(&wrapR, err, o, "wrapR", false);  // tinygltf extension
+
+  // TODO(syoyo): Check the value is alloed one.
+  // (e.g. we allow 9728(NEAREST), but don't allow 9727)
+
+  sampler->minFilter = minFilter;
+  sampler->magFilter = magFilter;
+  sampler->wrapS = wrapS;
+  sampler->wrapT = wrapT;
+  sampler->wrapR = wrapR;
+
+  ParseExtensionsProperty(&(sampler->extensions), err, o);
+  ParseExtrasProperty(&(sampler->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        sampler->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        sampler->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseSkin(Skin *skin, std::string *err, const json &o,
+                      bool store_original_json_for_extras_and_extensions) {
+  ParseStringProperty(&skin->name, err, o, "name", false, "Skin");
+
+  std::vector<int> joints;
+  if (!ParseIntegerArrayProperty(&joints, err, o, "joints", false, "Skin")) {
+    return false;
+  }
+  skin->joints = std::move(joints);
+
+  int skeleton = -1;
+  ParseIntegerProperty(&skeleton, err, o, "skeleton", false, "Skin");
+  skin->skeleton = skeleton;
+
+  int invBind = -1;
+  ParseIntegerProperty(&invBind, err, o, "inverseBindMatrices", true, "Skin");
+  skin->inverseBindMatrices = invBind;
+
+  ParseExtensionsProperty(&(skin->extensions), err, o);
+  ParseExtrasProperty(&(skin->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        skin->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        skin->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParsePerspectiveCamera(
+    PerspectiveCamera *camera, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  double yfov = 0.0;
+  if (!ParseNumberProperty(&yfov, err, o, "yfov", true, "OrthographicCamera")) {
+    return false;
+  }
+
+  double znear = 0.0;
+  if (!ParseNumberProperty(&znear, err, o, "znear", true,
+                           "PerspectiveCamera")) {
+    return false;
+  }
+
+  double aspectRatio = 0.0;  // = invalid
+  ParseNumberProperty(&aspectRatio, err, o, "aspectRatio", false,
+                      "PerspectiveCamera");
+
+  double zfar = 0.0;  // = invalid
+  ParseNumberProperty(&zfar, err, o, "zfar", false, "PerspectiveCamera");
+
+  camera->aspectRatio = aspectRatio;
+  camera->zfar = zfar;
+  camera->yfov = yfov;
+  camera->znear = znear;
+
+  ParseExtensionsProperty(&camera->extensions, err, o);
+  ParseExtrasProperty(&(camera->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        camera->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        camera->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  // TODO(syoyo): Validate parameter values.
+
+  return true;
+}
+
+static bool ParseSpotLight(SpotLight *light, std::string *err, const json &o,
+                           bool store_original_json_for_extras_and_extensions) {
+  ParseNumberProperty(&light->innerConeAngle, err, o, "innerConeAngle", false);
+  ParseNumberProperty(&light->outerConeAngle, err, o, "outerConeAngle", false);
+
+  ParseExtensionsProperty(&light->extensions, err, o);
+  ParseExtrasProperty(&light->extras, o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        light->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        light->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  // TODO(syoyo): Validate parameter values.
+
+  return true;
+}
+
+static bool ParseOrthographicCamera(
+    OrthographicCamera *camera, std::string *err, const json &o,
+    bool store_original_json_for_extras_and_extensions) {
+  double xmag = 0.0;
+  if (!ParseNumberProperty(&xmag, err, o, "xmag", true, "OrthographicCamera")) {
+    return false;
+  }
+
+  double ymag = 0.0;
+  if (!ParseNumberProperty(&ymag, err, o, "ymag", true, "OrthographicCamera")) {
+    return false;
+  }
+
+  double zfar = 0.0;
+  if (!ParseNumberProperty(&zfar, err, o, "zfar", true, "OrthographicCamera")) {
+    return false;
+  }
+
+  double znear = 0.0;
+  if (!ParseNumberProperty(&znear, err, o, "znear", true,
+                           "OrthographicCamera")) {
+    return false;
+  }
+
+  ParseExtensionsProperty(&camera->extensions, err, o);
+  ParseExtrasProperty(&(camera->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        camera->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        camera->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  camera->xmag = xmag;
+  camera->ymag = ymag;
+  camera->zfar = zfar;
+  camera->znear = znear;
+
+  // TODO(syoyo): Validate parameter values.
+
+  return true;
+}
+
+static bool ParseCamera(Camera *camera, std::string *err, const json &o,
+                        bool store_original_json_for_extras_and_extensions) {
+  if (!ParseStringProperty(&camera->type, err, o, "type", true, "Camera")) {
+    return false;
+  }
+
+  if (camera->type.compare("orthographic") == 0) {
+    json_const_iterator orthoIt;
+    if (!FindMember(o, "orthographic", orthoIt)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "Orhographic camera description not found." << std::endl;
+        (*err) += ss.str();
+      }
+      return false;
+    }
+
+    const json &v = GetValue(orthoIt);
+    if (!IsObject(v)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "\"orthographic\" is not a JSON object." << std::endl;
+        (*err) += ss.str();
+      }
+      return false;
+    }
+
+    if (!ParseOrthographicCamera(
+            &camera->orthographic, err, v,
+            store_original_json_for_extras_and_extensions)) {
+      return false;
+    }
+  } else if (camera->type.compare("perspective") == 0) {
+    json_const_iterator perspIt;
+    if (!FindMember(o, "perspective", perspIt)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "Perspective camera description not found." << std::endl;
+        (*err) += ss.str();
+      }
+      return false;
+    }
+
+    const json &v = GetValue(perspIt);
+    if (!IsObject(v)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "\"perspective\" is not a JSON object." << std::endl;
+        (*err) += ss.str();
+      }
+      return false;
+    }
+
+    if (!ParsePerspectiveCamera(
+            &camera->perspective, err, v,
+            store_original_json_for_extras_and_extensions)) {
+      return false;
+    }
+  } else {
+    if (err) {
+      std::stringstream ss;
+      ss << "Invalid camera type: \"" << camera->type
+         << "\". Must be \"perspective\" or \"orthographic\"" << std::endl;
+      (*err) += ss.str();
+    }
+    return false;
+  }
+
+  ParseStringProperty(&camera->name, err, o, "name", false);
+
+  ParseExtensionsProperty(&camera->extensions, err, o);
+  ParseExtrasProperty(&(camera->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        camera->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        camera->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+static bool ParseLight(Light *light, std::string *err, const json &o,
+                       bool store_original_json_for_extras_and_extensions) {
+  if (!ParseStringProperty(&light->type, err, o, "type", true)) {
+    return false;
+  }
+
+  if (light->type == "spot") {
+    json_const_iterator spotIt;
+    if (!FindMember(o, "spot", spotIt)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "Spot light description not found." << std::endl;
+        (*err) += ss.str();
+      }
+      return false;
+    }
+
+    const json &v = GetValue(spotIt);
+    if (!IsObject(v)) {
+      if (err) {
+        std::stringstream ss;
+        ss << "\"spot\" is not a JSON object." << std::endl;
+        (*err) += ss.str();
+      }
+      return false;
+    }
+
+    if (!ParseSpotLight(&light->spot, err, v,
+                        store_original_json_for_extras_and_extensions)) {
+      return false;
+    }
+  }
+
+  ParseStringProperty(&light->name, err, o, "name", false);
+  ParseNumberArrayProperty(&light->color, err, o, "color", false);
+  ParseNumberProperty(&light->range, err, o, "range", false);
+  ParseNumberProperty(&light->intensity, err, o, "intensity", false);
+  ParseExtensionsProperty(&light->extensions, err, o);
+  ParseExtrasProperty(&(light->extras), o);
+
+  if (store_original_json_for_extras_and_extensions) {
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        light->extensions_json_string = JsonToString(GetValue(it));
+      }
+    }
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extras", it)) {
+        light->extras_json_string = JsonToString(GetValue(it));
+      }
+    }
+  }
+
+  return true;
+}
+
+bool TinyGLTF::LoadFromString(Model *model, std::string *err, std::string *warn,
+                              const char *json_str,
+                              unsigned int json_str_length,
+                              const std::string &base_dir,
+                              unsigned int check_sections) {
+  if (json_str_length < 4) {
+    if (err) {
+      (*err) = "JSON string too short.\n";
+    }
+    return false;
+  }
+
+  JsonDocument v;
+
+#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || \
+     defined(_CPPUNWIND)) &&                               \
+    !defined(TINYGLTF_NOEXCEPTION)
+  try {
+    JsonParse(v, json_str, json_str_length, true);
+
+  } catch (const std::exception &e) {
+    if (err) {
+      (*err) = e.what();
+    }
+    return false;
+  }
+#else
+  {
+    JsonParse(v, json_str, json_str_length);
+
+    if (!IsObject(v)) {
+      // Assume parsing was failed.
+      if (err) {
+        (*err) = "Failed to parse JSON object\n";
+      }
+      return false;
+    }
+  }
+#endif
+
+  if (!IsObject(v)) {
+    // root is not an object.
+    if (err) {
+      (*err) = "Root element is not a JSON object\n";
+    }
+    return false;
+  }
+
+  {
+    bool version_found = false;
+    json_const_iterator it;
+    if (FindMember(v, "asset", it) && IsObject(GetValue(it))) {
+      auto &itObj = GetValue(it);
+      json_const_iterator version_it;
+      std::string versionStr;
+      if (FindMember(itObj, "version", version_it) &&
+          GetString(GetValue(version_it), versionStr)) {
+        version_found = true;
+      }
+    }
+    if (version_found) {
+      // OK
+    } else if (check_sections & REQUIRE_VERSION) {
+      if (err) {
+        (*err) += "\"asset\" object not found in .gltf or not an object type\n";
+      }
+      return false;
+    }
+  }
+
+  // scene is not mandatory.
+  // FIXME Maybe a better way to handle it than removing the code
+
+  auto IsArrayMemberPresent = [](const json &_v, const char *name) -> bool {
+    json_const_iterator it;
+    return FindMember(_v, name, it) && IsArray(GetValue(it));
+  };
+
+  {
+    if ((check_sections & REQUIRE_SCENES) &&
+        !IsArrayMemberPresent(v, "scenes")) {
+      if (err) {
+        (*err) += "\"scenes\" object not found in .gltf or not an array type\n";
+      }
+      return false;
+    }
+  }
+
+  {
+    if ((check_sections & REQUIRE_NODES) && !IsArrayMemberPresent(v, "nodes")) {
+      if (err) {
+        (*err) += "\"nodes\" object not found in .gltf\n";
+      }
+      return false;
+    }
+  }
+
+  {
+    if ((check_sections & REQUIRE_ACCESSORS) &&
+        !IsArrayMemberPresent(v, "accessors")) {
+      if (err) {
+        (*err) += "\"accessors\" object not found in .gltf\n";
+      }
+      return false;
+    }
+  }
+
+  {
+    if ((check_sections & REQUIRE_BUFFERS) &&
+        !IsArrayMemberPresent(v, "buffers")) {
+      if (err) {
+        (*err) += "\"buffers\" object not found in .gltf\n";
+      }
+      return false;
+    }
+  }
+
+  {
+    if ((check_sections & REQUIRE_BUFFER_VIEWS) &&
+        !IsArrayMemberPresent(v, "bufferViews")) {
+      if (err) {
+        (*err) += "\"bufferViews\" object not found in .gltf\n";
+      }
+      return false;
+    }
+  }
+
+  model->buffers.clear();
+  model->bufferViews.clear();
+  model->accessors.clear();
+  model->meshes.clear();
+  model->cameras.clear();
+  model->nodes.clear();
+  model->extensionsUsed.clear();
+  model->extensionsRequired.clear();
+  model->extensions.clear();
+  model->defaultScene = -1;
+
+  // 1. Parse Asset
+  {
+    json_const_iterator it;
+    if (FindMember(v, "asset", it) && IsObject(GetValue(it))) {
+      const json &root = GetValue(it);
+
+      ParseAsset(&model->asset, err, root,
+                 store_original_json_for_extras_and_extensions_);
+    }
+  }
+
+#ifdef TINYGLTF_USE_CPP14
+  auto ForEachInArray = [](const json &_v, const char *member,
+                           const auto &cb) -> bool
+#else
+  // The std::function<> implementation can be less efficient because it will
+  // allocate heap when the size of the captured lambda is above 16 bytes with
+  // clang and gcc, but it does not require C++14.
+  auto ForEachInArray = [](const json &_v, const char *member,
+                           const std::function<bool(const json &)> &cb) -> bool
+#endif
+  {
+    json_const_iterator itm;
+    if (FindMember(_v, member, itm) && IsArray(GetValue(itm))) {
+      const json &root = GetValue(itm);
+      auto it = ArrayBegin(root);
+      auto end = ArrayEnd(root);
+      for (; it != end; ++it) {
+        if (!cb(*it)) return false;
+      }
+    }
+    return true;
+  };
+
+  // 2. Parse extensionUsed
+  {
+    ForEachInArray(v, "extensionsUsed", [&](const json &o) {
+      std::string str;
+      GetString(o, str);
+      model->extensionsUsed.emplace_back(std::move(str));
+      return true;
+    });
+  }
+
+  {
+    ForEachInArray(v, "extensionsRequired", [&](const json &o) {
+      std::string str;
+      GetString(o, str);
+      model->extensionsRequired.emplace_back(std::move(str));
+      return true;
+    });
+  }
+
+  // 3. Parse Buffer
+  {
+    bool success = ForEachInArray(v, "buffers", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`buffers' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Buffer buffer;
+      if (!ParseBuffer(&buffer, err, o,
+                       store_original_json_for_extras_and_extensions_, &fs,
+                       base_dir, is_binary_, bin_data_, bin_size_)) {
+        return false;
+      }
+
+      model->buffers.emplace_back(std::move(buffer));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+  // 4. Parse BufferView
+  {
+    bool success = ForEachInArray(v, "bufferViews", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`bufferViews' does not contain an JSON object.";
+        }
+        return false;
+      }
+      BufferView bufferView;
+      if (!ParseBufferView(&bufferView, err, o,
+                           store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->bufferViews.emplace_back(std::move(bufferView));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 5. Parse Accessor
+  {
+    bool success = ForEachInArray(v, "accessors", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`accessors' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Accessor accessor;
+      if (!ParseAccessor(&accessor, err, o,
+                         store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->accessors.emplace_back(std::move(accessor));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 6. Parse Mesh
+  {
+    bool success = ForEachInArray(v, "meshes", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`meshes' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Mesh mesh;
+      if (!ParseMesh(&mesh, model, err, o,
+                     store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->meshes.emplace_back(std::move(mesh));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // Assign missing bufferView target types
+  // - Look for missing Mesh indices
+  // - Look for missing Mesh attributes
+  for (auto &mesh : model->meshes) {
+    for (auto &primitive : mesh.primitives) {
+      if (primitive.indices >
+          -1)  // has indices from parsing step, must be Element Array Buffer
+      {
+        if (size_t(primitive.indices) >= model->accessors.size()) {
+          if (err) {
+            (*err) += "primitive indices accessor out of bounds";
+          }
+          return false;
+        }
+
+        auto bufferView =
+            model->accessors[size_t(primitive.indices)].bufferView;
+        if (bufferView < 0 || size_t(bufferView) >= model->bufferViews.size()) {
+          if (err) {
+            (*err) += "accessor[" + std::to_string(primitive.indices) +
+                      "] invalid bufferView";
+          }
+          return false;
+        }
+
+        model->bufferViews[size_t(bufferView)].target =
+            TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER;
+        // we could optionally check if acessors' bufferView type is Scalar, as
+        // it should be
+      }
+
+      for (auto &attribute : primitive.attributes) {
+        model
+            ->bufferViews[size_t(
+                model->accessors[size_t(attribute.second)].bufferView)]
+            .target = TINYGLTF_TARGET_ARRAY_BUFFER;
+      }
+
+      for (auto &target : primitive.targets) {
+        for (auto &attribute : target) {
+          auto bufferView =
+              model->accessors[size_t(attribute.second)].bufferView;
+          // bufferView could be null(-1) for sparse morph target
+          if (bufferView >= 0) {
+            model->bufferViews[size_t(bufferView)].target =
+                TINYGLTF_TARGET_ARRAY_BUFFER;
+          }
+        }
+      }
+    }
+  }
+
+  // 7. Parse Node
+  {
+    bool success = ForEachInArray(v, "nodes", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`nodes' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Node node;
+      if (!ParseNode(&node, err, o,
+                     store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->nodes.emplace_back(std::move(node));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 8. Parse scenes.
+  {
+    bool success = ForEachInArray(v, "scenes", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`scenes' does not contain an JSON object.";
+        }
+        return false;
+      }
+      std::vector<int> nodes;
+      ParseIntegerArrayProperty(&nodes, err, o, "nodes", false);
+
+      Scene scene;
+      scene.nodes = std::move(nodes);
+
+      ParseStringProperty(&scene.name, err, o, "name", false);
+
+      ParseExtensionsProperty(&scene.extensions, err, o);
+      ParseExtrasProperty(&scene.extras, o);
+
+      if (store_original_json_for_extras_and_extensions_) {
+        {
+          json_const_iterator it;
+          if (FindMember(o, "extensions", it)) {
+            model->extensions_json_string = JsonToString(GetValue(it));
+          }
+        }
+        {
+          json_const_iterator it;
+          if (FindMember(o, "extras", it)) {
+            model->extras_json_string = JsonToString(GetValue(it));
+          }
+        }
+      }
+
+      model->scenes.emplace_back(std::move(scene));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 9. Parse default scenes.
+  {
+    json_const_iterator rootIt;
+    int iVal;
+    if (FindMember(v, "scene", rootIt) && GetInt(GetValue(rootIt), iVal)) {
+      model->defaultScene = iVal;
+    }
+  }
+
+  // 10. Parse Material
+  {
+    bool success = ForEachInArray(v, "materials", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`materials' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Material material;
+      ParseStringProperty(&material.name, err, o, "name", false);
+
+      if (!ParseMaterial(&material, err, o,
+                         store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->materials.emplace_back(std::move(material));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 11. Parse Image
+  {
+    int idx = 0;
+    bool success = ForEachInArray(v, "images", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "image[" + std::to_string(idx) + "] is not a JSON object.";
+        }
+        return false;
+      }
+      Image image;
+      if (!ParseImage(&image, idx, err, warn, o,
+                      store_original_json_for_extras_and_extensions_, base_dir,
+                      &fs, &this->LoadImageData, load_image_user_data_)) {
+        return false;
+      }
+
+      if (image.bufferView != -1) {
+        // Load image from the buffer view.
+        if (size_t(image.bufferView) >= model->bufferViews.size()) {
+          if (err) {
+            std::stringstream ss;
+            ss << "image[" << idx << "] bufferView \"" << image.bufferView
+               << "\" not found in the scene." << std::endl;
+            (*err) += ss.str();
+          }
+          return false;
+        }
+
+        const BufferView &bufferView =
+            model->bufferViews[size_t(image.bufferView)];
+        if (size_t(bufferView.buffer) >= model->buffers.size()) {
+          if (err) {
+            std::stringstream ss;
+            ss << "image[" << idx << "] buffer \"" << bufferView.buffer
+               << "\" not found in the scene." << std::endl;
+            (*err) += ss.str();
+          }
+          return false;
+        }
+        const Buffer &buffer = model->buffers[size_t(bufferView.buffer)];
+
+        if (*LoadImageData == nullptr) {
+          if (err) {
+            (*err) += "No LoadImageData callback specified.\n";
+          }
+          return false;
+        }
+        bool ret = LoadImageData(
+            &image, idx, err, warn, image.width, image.height,
+            &buffer.data[bufferView.byteOffset],
+            static_cast<int>(bufferView.byteLength), load_image_user_data_);
+        if (!ret) {
+          return false;
+        }
+      }
+
+      model->images.emplace_back(std::move(image));
+      ++idx;
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 12. Parse Texture
+  {
+    bool success = ForEachInArray(v, "textures", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`textures' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Texture texture;
+      if (!ParseTexture(&texture, err, o,
+                        store_original_json_for_extras_and_extensions_,
+                        base_dir)) {
+        return false;
+      }
+
+      model->textures.emplace_back(std::move(texture));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 13. Parse Animation
+  {
+    bool success = ForEachInArray(v, "animations", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`animations' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Animation animation;
+      if (!ParseAnimation(&animation, err, o,
+                          store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->animations.emplace_back(std::move(animation));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 14. Parse Skin
+  {
+    bool success = ForEachInArray(v, "skins", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`skins' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Skin skin;
+      if (!ParseSkin(&skin, err, o,
+                     store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->skins.emplace_back(std::move(skin));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 15. Parse Sampler
+  {
+    bool success = ForEachInArray(v, "samplers", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`samplers' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Sampler sampler;
+      if (!ParseSampler(&sampler, err, o,
+                        store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->samplers.emplace_back(std::move(sampler));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 16. Parse Camera
+  {
+    bool success = ForEachInArray(v, "cameras", [&](const json &o) {
+      if (!IsObject(o)) {
+        if (err) {
+          (*err) += "`cameras' does not contain an JSON object.";
+        }
+        return false;
+      }
+      Camera camera;
+      if (!ParseCamera(&camera, err, o,
+                       store_original_json_for_extras_and_extensions_)) {
+        return false;
+      }
+
+      model->cameras.emplace_back(std::move(camera));
+      return true;
+    });
+
+    if (!success) {
+      return false;
+    }
+  }
+
+  // 17. Parse Extensions
+  ParseExtensionsProperty(&model->extensions, err, v);
+
+  // 18. Specific extension implementations
+  {
+    json_const_iterator rootIt;
+    if (FindMember(v, "extensions", rootIt) && IsObject(GetValue(rootIt))) {
+      const json &root = GetValue(rootIt);
+
+      json_const_iterator it(ObjectBegin(root));
+      json_const_iterator itEnd(ObjectEnd(root));
+      for (; it != itEnd; ++it) {
+        // parse KHR_lights_punctual extension
+        std::string key(GetKey(it));
+        if ((key == "KHR_lights_punctual") && IsObject(GetValue(it))) {
+          const json &object = GetValue(it);
+          json_const_iterator itLight;
+          if (FindMember(object, "lights", itLight)) {
+            const json &lights = GetValue(itLight);
+            if (!IsArray(lights)) {
+              continue;
+            }
+
+            auto arrayIt(ArrayBegin(lights));
+            auto arrayItEnd(ArrayEnd(lights));
+            for (; arrayIt != arrayItEnd; ++arrayIt) {
+              Light light;
+              if (!ParseLight(&light, err, *arrayIt,
+                              store_original_json_for_extras_and_extensions_)) {
+                return false;
+              }
+              model->lights.emplace_back(std::move(light));
+            }
+          }
+        }
+      }
+    }
+  }
+
+  // 19. Parse Extras
+  ParseExtrasProperty(&model->extras, v);
+
+  if (store_original_json_for_extras_and_extensions_) {
+    model->extras_json_string = JsonToString(v["extras"]);
+    model->extensions_json_string = JsonToString(v["extensions"]);
+  }
+
+  return true;
+}
+
+bool TinyGLTF::LoadASCIIFromString(Model *model, std::string *err,
+                                   std::string *warn, const char *str,
+                                   unsigned int length,
+                                   const std::string &base_dir,
+                                   unsigned int check_sections) {
+  is_binary_ = false;
+  bin_data_ = nullptr;
+  bin_size_ = 0;
+
+  return LoadFromString(model, err, warn, str, length, base_dir,
+                        check_sections);
+}
+
+bool TinyGLTF::LoadASCIIFromFile(Model *model, std::string *err,
+                                 std::string *warn, const std::string &filename,
+                                 unsigned int check_sections) {
+  std::stringstream ss;
+
+  if (fs.ReadWholeFile == nullptr) {
+    // Programmer error, assert() ?
+    ss << "Failed to read file: " << filename
+       << ": one or more FS callback not set" << std::endl;
+    if (err) {
+      (*err) = ss.str();
+    }
+    return false;
+  }
+
+  std::vector<unsigned char> data;
+  std::string fileerr;
+  bool fileread = fs.ReadWholeFile(&data, &fileerr, filename, fs.user_data);
+  if (!fileread) {
+    ss << "Failed to read file: " << filename << ": " << fileerr << std::endl;
+    if (err) {
+      (*err) = ss.str();
+    }
+    return false;
+  }
+
+  size_t sz = data.size();
+  if (sz == 0) {
+    if (err) {
+      (*err) = "Empty file.";
+    }
+    return false;
+  }
+
+  std::string basedir = GetBaseDir(filename);
+
+  bool ret = LoadASCIIFromString(
+      model, err, warn, reinterpret_cast<const char *>(&data.at(0)),
+      static_cast<unsigned int>(data.size()), basedir, check_sections);
+
+  return ret;
+}
+
+bool TinyGLTF::LoadBinaryFromMemory(Model *model, std::string *err,
+                                    std::string *warn,
+                                    const unsigned char *bytes,
+                                    unsigned int size,
+                                    const std::string &base_dir,
+                                    unsigned int check_sections) {
+  if (size < 20) {
+    if (err) {
+      (*err) = "Too short data size for glTF Binary.";
+    }
+    return false;
+  }
+
+  if (bytes[0] == 'g' && bytes[1] == 'l' && bytes[2] == 'T' &&
+      bytes[3] == 'F') {
+    // ok
+  } else {
+    if (err) {
+      (*err) = "Invalid magic.";
+    }
+    return false;
+  }
+
+  unsigned int version;       // 4 bytes
+  unsigned int length;        // 4 bytes
+  unsigned int model_length;  // 4 bytes
+  unsigned int model_format;  // 4 bytes;
+
+  // @todo { Endian swap for big endian machine. }
+  memcpy(&version, bytes + 4, 4);
+  swap4(&version);
+  memcpy(&length, bytes + 8, 4);
+  swap4(&length);
+  memcpy(&model_length, bytes + 12, 4);
+  swap4(&model_length);
+  memcpy(&model_format, bytes + 16, 4);
+  swap4(&model_format);
+
+  // In case the Bin buffer is not present, the size is exactly 20 + size of
+  // JSON contents,
+  // so use "greater than" operator.
+  if ((20 + model_length > size) || (model_length < 1) || (length > size) ||
+      (20 + model_length > length) ||
+      (model_format != 0x4E4F534A)) {  // 0x4E4F534A = JSON format.
+    if (err) {
+      (*err) = "Invalid glTF binary.";
+    }
+    return false;
+  }
+
+  // Extract JSON string.
+  std::string jsonString(reinterpret_cast<const char *>(&bytes[20]),
+                         model_length);
+
+  is_binary_ = true;
+  bin_data_ = bytes + 20 + model_length +
+              8;  // 4 bytes (buffer_length) + 4 bytes(buffer_format)
+  bin_size_ =
+      length - (20 + model_length);  // extract header + JSON scene data.
+
+  bool ret = LoadFromString(model, err, warn,
+                            reinterpret_cast<const char *>(&bytes[20]),
+                            model_length, base_dir, check_sections);
+  if (!ret) {
+    return ret;
+  }
+
+  return true;
+}
+
+bool TinyGLTF::LoadBinaryFromFile(Model *model, std::string *err,
+                                  std::string *warn,
+                                  const std::string &filename,
+                                  unsigned int check_sections) {
+  std::stringstream ss;
+
+  if (fs.ReadWholeFile == nullptr) {
+    // Programmer error, assert() ?
+    ss << "Failed to read file: " << filename
+       << ": one or more FS callback not set" << std::endl;
+    if (err) {
+      (*err) = ss.str();
+    }
+    return false;
+  }
+
+  std::vector<unsigned char> data;
+  std::string fileerr;
+  bool fileread = fs.ReadWholeFile(&data, &fileerr, filename, fs.user_data);
+  if (!fileread) {
+    ss << "Failed to read file: " << filename << ": " << fileerr << std::endl;
+    if (err) {
+      (*err) = ss.str();
+    }
+    return false;
+  }
+
+  std::string basedir = GetBaseDir(filename);
+
+  bool ret = LoadBinaryFromMemory(model, err, warn, &data.at(0),
+                                  static_cast<unsigned int>(data.size()),
+                                  basedir, check_sections);
+
+  return ret;
+}
+
+///////////////////////
+// GLTF Serialization
+///////////////////////
+namespace {
+json JsonFromString(const char *s) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return json(s, GetAllocator());
+#else
+  return json(s);
+#endif
+}
+
+void JsonAssign(json &dest, const json &src) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  dest.CopyFrom(src, GetAllocator());
+#else
+  dest = src;
+#endif
+}
+
+void JsonAddMember(json &o, const char *key, json &&value) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  if (!o.IsObject()) {
+    o.SetObject();
+  }
+  o.AddMember(json(key, GetAllocator()), std::move(value), GetAllocator());
+#else
+  o[key] = std::move(value);
+#endif
+}
+
+void JsonPushBack(json &o, json &&value) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  o.PushBack(std::move(value), GetAllocator());
+#else
+  o.push_back(std::move(value));
+#endif
+}
+
+bool JsonIsNull(const json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  return o.IsNull();
+#else
+  return o.is_null();
+#endif
+}
+
+void JsonSetObject(json &o) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  o.SetObject();
+#else
+  o = o.object({});
+#endif
+}
+
+void JsonReserveArray(json &o, size_t s) {
+#ifdef TINYGLTF_USE_RAPIDJSON
+  o.SetArray();
+  o.Reserve(static_cast<rapidjson::SizeType>(s), GetAllocator());
+#endif
+  (void)(o);
+  (void)(s);
+}
+}  // namespace
+
+// typedef std::pair<std::string, json> json_object_pair;
+
+template <typename T>
+static void SerializeNumberProperty(const std::string &key, T number,
+                                    json &obj) {
+  // obj.insert(
+  //    json_object_pair(key, json(static_cast<double>(number))));
+  // obj[key] = static_cast<double>(number);
+  JsonAddMember(obj, key.c_str(), json(number));
+}
+
+#ifdef TINYGLTF_USE_RAPIDJSON
+template <>
+void SerializeNumberProperty(const std::string &key, size_t number, json &obj) {
+  JsonAddMember(obj, key.c_str(), json(static_cast<uint64_t>(number)));
+}
+#endif
+
+template <typename T>
+static void SerializeNumberArrayProperty(const std::string &key,
+                                         const std::vector<T> &value,
+                                         json &obj) {
+  if (value.empty()) return;
+
+  json ary;
+  JsonReserveArray(ary, value.size());
+  for (const auto &s : value) {
+    JsonPushBack(ary, json(s));
+  }
+  JsonAddMember(obj, key.c_str(), std::move(ary));
+}
+
+static void SerializeStringProperty(const std::string &key,
+                                    const std::string &value, json &obj) {
+  JsonAddMember(obj, key.c_str(), JsonFromString(value.c_str()));
+}
+
+static void SerializeStringArrayProperty(const std::string &key,
+                                         const std::vector<std::string> &value,
+                                         json &obj) {
+  json ary;
+  JsonReserveArray(ary, value.size());
+  for (auto &s : value) {
+    JsonPushBack(ary, JsonFromString(s.c_str()));
+  }
+  JsonAddMember(obj, key.c_str(), std::move(ary));
+}
+
+static bool ValueToJson(const Value &value, json *ret) {
+  json obj;
+#ifdef TINYGLTF_USE_RAPIDJSON
+  switch (value.Type()) {
+    case REAL_TYPE:
+      obj.SetDouble(value.Get<double>());
+      break;
+    case INT_TYPE:
+      obj.SetInt(value.Get<int>());
+      break;
+    case BOOL_TYPE:
+      obj.SetBool(value.Get<bool>());
+      break;
+    case STRING_TYPE:
+      obj.SetString(value.Get<std::string>().c_str(), GetAllocator());
+      break;
+    case ARRAY_TYPE: {
+      obj.SetArray();
+      obj.Reserve(static_cast<rapidjson::SizeType>(value.ArrayLen()),
+                  GetAllocator());
+      for (unsigned int i = 0; i < value.ArrayLen(); ++i) {
+        Value elementValue = value.Get(int(i));
+        json elementJson;
+        if (ValueToJson(value.Get(int(i)), &elementJson))
+          obj.PushBack(std::move(elementJson), GetAllocator());
+      }
+      break;
+    }
+    case BINARY_TYPE:
+      // TODO
+      // obj = json(value.Get<std::vector<unsigned char>>());
+      return false;
+      break;
+    case OBJECT_TYPE: {
+      obj.SetObject();
+      Value::Object objMap = value.Get<Value::Object>();
+      for (auto &it : objMap) {
+        json elementJson;
+        if (ValueToJson(it.second, &elementJson)) {
+          obj.AddMember(json(it.first.c_str(), GetAllocator()),
+                        std::move(elementJson), GetAllocator());
+        }
+      }
+      break;
+    }
+    case NULL_TYPE:
+    default:
+      return false;
+  }
+#else
+  switch (value.Type()) {
+    case REAL_TYPE:
+      obj = json(value.Get<double>());
+      break;
+    case INT_TYPE:
+      obj = json(value.Get<int>());
+      break;
+    case BOOL_TYPE:
+      obj = json(value.Get<bool>());
+      break;
+    case STRING_TYPE:
+      obj = json(value.Get<std::string>());
+      break;
+    case ARRAY_TYPE: {
+      for (unsigned int i = 0; i < value.ArrayLen(); ++i) {
+        Value elementValue = value.Get(int(i));
+        json elementJson;
+        if (ValueToJson(value.Get(int(i)), &elementJson))
+          obj.push_back(elementJson);
+      }
+      break;
+    }
+    case BINARY_TYPE:
+      // TODO
+      // obj = json(value.Get<std::vector<unsigned char>>());
+      return false;
+      break;
+    case OBJECT_TYPE: {
+      Value::Object objMap = value.Get<Value::Object>();
+      for (auto &it : objMap) {
+        json elementJson;
+        if (ValueToJson(it.second, &elementJson)) obj[it.first] = elementJson;
+      }
+      break;
+    }
+    case NULL_TYPE:
+    default:
+      return false;
+  }
+#endif
+  if (ret) *ret = std::move(obj);
+  return true;
+}
+
+static void SerializeValue(const std::string &key, const Value &value,
+                           json &obj) {
+  json ret;
+  if (ValueToJson(value, &ret)) {
+    JsonAddMember(obj, key.c_str(), std::move(ret));
+  }
+}
+
+static void SerializeGltfBufferData(const std::vector<unsigned char> &data,
+                                    json &o) {
+  std::string header = "data:application/octet-stream;base64,";
+  if (data.size() > 0) {
+    std::string encodedData =
+        base64_encode(&data[0], static_cast<unsigned int>(data.size()));
+    SerializeStringProperty("uri", header + encodedData, o);
+  } else {
+    // Issue #229
+    // size 0 is allowd. Just emit mime header.
+    SerializeStringProperty("uri", header, o);
+  }
+}
+
+static bool SerializeGltfBufferData(const std::vector<unsigned char> &data,
+                                    const std::string &binFilename) {
+#ifdef _WIN32
+#if defined(__GLIBCXX__)  // mingw
+  int file_descriptor = _wopen(UTF8ToWchar(binFilename).c_str(),
+                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
+  __gnu_cxx::stdio_filebuf<char> wfile_buf(
+      file_descriptor, std::ios_base::out | std::ios_base::binary);
+  std::ostream output(&wfile_buf);
+  if (!wfile_buf.is_open()) return false;
+#elif defined(_MSC_VER)
+  std::ofstream output(UTF8ToWchar(binFilename).c_str(), std::ofstream::binary);
+  if (!output.is_open()) return false;
+#else
+  std::ofstream output(binFilename.c_str(), std::ofstream::binary);
+  if (!output.is_open()) return false;
+#endif
+#else
+  std::ofstream output(binFilename.c_str(), std::ofstream::binary);
+  if (!output.is_open()) return false;
+#endif
+  if (data.size() > 0) {
+    output.write(reinterpret_cast<const char *>(&data[0]),
+                 std::streamsize(data.size()));
+  } else {
+    // Issue #229
+    // size 0 will be still valid buffer data.
+    // write empty file.
+  }
+  return true;
+}
+
+#if 0  // FIXME(syoyo): not used. will be removed in the future release.
+static void SerializeParameterMap(ParameterMap &param, json &o) {
+  for (ParameterMap::iterator paramIt = param.begin(); paramIt != param.end();
+       ++paramIt) {
+    if (paramIt->second.number_array.size()) {
+      SerializeNumberArrayProperty<double>(paramIt->first,
+                                           paramIt->second.number_array, o);
+    } else if (paramIt->second.json_double_value.size()) {
+      json json_double_value;
+      for (std::map<std::string, double>::iterator it =
+               paramIt->second.json_double_value.begin();
+           it != paramIt->second.json_double_value.end(); ++it) {
+        if (it->first == "index") {
+          json_double_value[it->first] = paramIt->second.TextureIndex();
+        } else {
+          json_double_value[it->first] = it->second;
+        }
+      }
+
+      o[paramIt->first] = json_double_value;
+    } else if (!paramIt->second.string_value.empty()) {
+      SerializeStringProperty(paramIt->first, paramIt->second.string_value, o);
+    } else if (paramIt->second.has_number_value) {
+      o[paramIt->first] = paramIt->second.number_value;
+    } else {
+      o[paramIt->first] = paramIt->second.bool_value;
+    }
+  }
+}
+#endif
+
+static void SerializeExtensionMap(const ExtensionMap &extensions, json &o) {
+  if (!extensions.size()) return;
+
+  json extMap;
+  for (ExtensionMap::const_iterator extIt = extensions.begin();
+       extIt != extensions.end(); ++extIt) {
+    // Allow an empty object for extension(#97)
+    json ret;
+    bool isNull = true;
+    if (ValueToJson(extIt->second, &ret)) {
+      isNull = JsonIsNull(ret);
+      JsonAddMember(extMap, extIt->first.c_str(), std::move(ret));
+    }
+    if (isNull) {
+      if (!(extIt->first.empty())) {  // name should not be empty, but for sure
+        // create empty object so that an extension name is still included in
+        // json.
+        json empty;
+        JsonSetObject(empty);
+        JsonAddMember(extMap, extIt->first.c_str(), std::move(empty));
+      }
+    }
+  }
+  JsonAddMember(o, "extensions", std::move(extMap));
+}
+
+static void SerializeGltfAccessor(Accessor &accessor, json &o) {
+  if (accessor.bufferView >= 0)
+    SerializeNumberProperty<int>("bufferView", accessor.bufferView, o);
+
+  if (accessor.byteOffset != 0)
+    SerializeNumberProperty<int>("byteOffset", int(accessor.byteOffset), o);
+
+  SerializeNumberProperty<int>("componentType", accessor.componentType, o);
+  SerializeNumberProperty<size_t>("count", accessor.count, o);
+  SerializeNumberArrayProperty<double>("min", accessor.minValues, o);
+  SerializeNumberArrayProperty<double>("max", accessor.maxValues, o);
+  if (accessor.normalized)
+    SerializeValue("normalized", Value(accessor.normalized), o);
+  std::string type;
+  switch (accessor.type) {
+    case TINYGLTF_TYPE_SCALAR:
+      type = "SCALAR";
+      break;
+    case TINYGLTF_TYPE_VEC2:
+      type = "VEC2";
+      break;
+    case TINYGLTF_TYPE_VEC3:
+      type = "VEC3";
+      break;
+    case TINYGLTF_TYPE_VEC4:
+      type = "VEC4";
+      break;
+    case TINYGLTF_TYPE_MAT2:
+      type = "MAT2";
+      break;
+    case TINYGLTF_TYPE_MAT3:
+      type = "MAT3";
+      break;
+    case TINYGLTF_TYPE_MAT4:
+      type = "MAT4";
+      break;
+  }
+
+  SerializeStringProperty("type", type, o);
+  if (!accessor.name.empty()) SerializeStringProperty("name", accessor.name, o);
+
+  if (accessor.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", accessor.extras, o);
+  }
+}
+
+static void SerializeGltfAnimationChannel(AnimationChannel &channel, json &o) {
+  SerializeNumberProperty("sampler", channel.sampler, o);
+  {
+    json target;
+    SerializeNumberProperty("node", channel.target_node, target);
+    SerializeStringProperty("path", channel.target_path, target);
+
+    SerializeExtensionMap(channel.target_extensions, target);
+
+    JsonAddMember(o, "target", std::move(target));
+  }
+
+  if (channel.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", channel.extras, o);
+  }
+
+  SerializeExtensionMap(channel.extensions, o);
+}
+
+static void SerializeGltfAnimationSampler(AnimationSampler &sampler, json &o) {
+  SerializeNumberProperty("input", sampler.input, o);
+  SerializeNumberProperty("output", sampler.output, o);
+  SerializeStringProperty("interpolation", sampler.interpolation, o);
+
+  if (sampler.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", sampler.extras, o);
+  }
+}
+
+static void SerializeGltfAnimation(Animation &animation, json &o) {
+  if (!animation.name.empty())
+    SerializeStringProperty("name", animation.name, o);
+
+  {
+    json channels;
+    JsonReserveArray(channels, animation.channels.size());
+    for (unsigned int i = 0; i < animation.channels.size(); ++i) {
+      json channel;
+      AnimationChannel gltfChannel = animation.channels[i];
+      SerializeGltfAnimationChannel(gltfChannel, channel);
+      JsonPushBack(channels, std::move(channel));
+    }
+
+    JsonAddMember(o, "channels", std::move(channels));
+  }
+
+  {
+    json samplers;
+    JsonReserveArray(samplers, animation.samplers.size());
+    for (unsigned int i = 0; i < animation.samplers.size(); ++i) {
+      json sampler;
+      AnimationSampler gltfSampler = animation.samplers[i];
+      SerializeGltfAnimationSampler(gltfSampler, sampler);
+      JsonPushBack(samplers, std::move(sampler));
+    }
+    JsonAddMember(o, "samplers", std::move(samplers));
+  }
+
+  if (animation.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", animation.extras, o);
+  }
+
+  SerializeExtensionMap(animation.extensions, o);
+}
+
+static void SerializeGltfAsset(Asset &asset, json &o) {
+  if (!asset.generator.empty()) {
+    SerializeStringProperty("generator", asset.generator, o);
+  }
+
+  if (!asset.copyright.empty()) {
+    SerializeStringProperty("copyright", asset.copyright, o);
+  }
+
+  if (!asset.version.empty()) {
+    SerializeStringProperty("version", asset.version, o);
+  }
+
+  if (asset.extras.Keys().size()) {
+    SerializeValue("extras", asset.extras, o);
+  }
+
+  SerializeExtensionMap(asset.extensions, o);
+}
+
+static void SerializeGltfBufferBin(Buffer &buffer, json &o,
+                                   std::vector<unsigned char> &binBuffer) {
+  SerializeNumberProperty("byteLength", buffer.data.size(), o);
+  binBuffer = buffer.data;
+
+  if (buffer.name.size()) SerializeStringProperty("name", buffer.name, o);
+
+  if (buffer.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", buffer.extras, o);
+  }
+}
+
+static void SerializeGltfBuffer(Buffer &buffer, json &o) {
+  SerializeNumberProperty("byteLength", buffer.data.size(), o);
+  SerializeGltfBufferData(buffer.data, o);
+
+  if (buffer.name.size()) SerializeStringProperty("name", buffer.name, o);
+
+  if (buffer.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", buffer.extras, o);
+  }
+}
+
+static bool SerializeGltfBuffer(Buffer &buffer, json &o,
+                                const std::string &binFilename,
+                                const std::string &binBaseFilename) {
+  if (!SerializeGltfBufferData(buffer.data, binFilename)) return false;
+  SerializeNumberProperty("byteLength", buffer.data.size(), o);
+  SerializeStringProperty("uri", binBaseFilename, o);
+
+  if (buffer.name.size()) SerializeStringProperty("name", buffer.name, o);
+
+  if (buffer.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", buffer.extras, o);
+  }
+  return true;
+}
+
+static void SerializeGltfBufferView(BufferView &bufferView, json &o) {
+  SerializeNumberProperty("buffer", bufferView.buffer, o);
+  SerializeNumberProperty<size_t>("byteLength", bufferView.byteLength, o);
+
+  // byteStride is optional, minimum allowed is 4
+  if (bufferView.byteStride >= 4) {
+    SerializeNumberProperty<size_t>("byteStride", bufferView.byteStride, o);
+  }
+  // byteOffset is optional, default is 0
+  if (bufferView.byteOffset > 0) {
+    SerializeNumberProperty<size_t>("byteOffset", bufferView.byteOffset, o);
+  }
+  // Target is optional, check if it contains a valid value
+  if (bufferView.target == TINYGLTF_TARGET_ARRAY_BUFFER ||
+      bufferView.target == TINYGLTF_TARGET_ELEMENT_ARRAY_BUFFER) {
+    SerializeNumberProperty("target", bufferView.target, o);
+  }
+  if (bufferView.name.size()) {
+    SerializeStringProperty("name", bufferView.name, o);
+  }
+
+  if (bufferView.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", bufferView.extras, o);
+  }
+}
+
+static void SerializeGltfImage(Image &image, json &o) {
+  // if uri empty, the mimeType and bufferview should be set
+  if (image.uri.empty()) {
+    SerializeStringProperty("mimeType", image.mimeType, o);
+    SerializeNumberProperty<int>("bufferView", image.bufferView, o);
+  } else {
+    // TODO(syoyo): dlib::urilencode?
+    SerializeStringProperty("uri", image.uri, o);
+  }
+
+  if (image.name.size()) {
+    SerializeStringProperty("name", image.name, o);
+  }
+
+  if (image.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", image.extras, o);
+  }
+
+  SerializeExtensionMap(image.extensions, o);
+}
+
+static void SerializeGltfTextureInfo(TextureInfo &texinfo, json &o) {
+  SerializeNumberProperty("index", texinfo.index, o);
+
+  if (texinfo.texCoord != 0) {
+    SerializeNumberProperty("texCoord", texinfo.texCoord, o);
+  }
+
+  if (texinfo.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", texinfo.extras, o);
+  }
+
+  SerializeExtensionMap(texinfo.extensions, o);
+}
+
+static void SerializeGltfNormalTextureInfo(NormalTextureInfo &texinfo,
+                                           json &o) {
+  SerializeNumberProperty("index", texinfo.index, o);
+
+  if (texinfo.texCoord != 0) {
+    SerializeNumberProperty("texCoord", texinfo.texCoord, o);
+  }
+
+  if (!TINYGLTF_DOUBLE_EQUAL(texinfo.scale, 1.0)) {
+    SerializeNumberProperty("scale", texinfo.scale, o);
+  }
+
+  if (texinfo.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", texinfo.extras, o);
+  }
+
+  SerializeExtensionMap(texinfo.extensions, o);
+}
+
+static void SerializeGltfOcclusionTextureInfo(OcclusionTextureInfo &texinfo,
+                                              json &o) {
+  SerializeNumberProperty("index", texinfo.index, o);
+
+  if (texinfo.texCoord != 0) {
+    SerializeNumberProperty("texCoord", texinfo.texCoord, o);
+  }
+
+  if (!TINYGLTF_DOUBLE_EQUAL(texinfo.strength, 1.0)) {
+    SerializeNumberProperty("strength", texinfo.strength, o);
+  }
+
+  if (texinfo.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", texinfo.extras, o);
+  }
+
+  SerializeExtensionMap(texinfo.extensions, o);
+}
+
+static void SerializeGltfPbrMetallicRoughness(PbrMetallicRoughness &pbr,
+                                              json &o) {
+  std::vector<double> default_baseColorFactor = {1.0, 1.0, 1.0, 1.0};
+  if (!Equals(pbr.baseColorFactor, default_baseColorFactor)) {
+    SerializeNumberArrayProperty<double>("baseColorFactor", pbr.baseColorFactor,
+                                         o);
+  }
+
+  if (!TINYGLTF_DOUBLE_EQUAL(pbr.metallicFactor, 1.0)) {
+    SerializeNumberProperty("metallicFactor", pbr.metallicFactor, o);
+  }
+
+  if (!TINYGLTF_DOUBLE_EQUAL(pbr.roughnessFactor, 1.0)) {
+    SerializeNumberProperty("roughnessFactor", pbr.roughnessFactor, o);
+  }
+
+  if (pbr.baseColorTexture.index > -1) {
+    json texinfo;
+    SerializeGltfTextureInfo(pbr.baseColorTexture, texinfo);
+    JsonAddMember(o, "baseColorTexture", std::move(texinfo));
+  }
+
+  if (pbr.metallicRoughnessTexture.index > -1) {
+    json texinfo;
+    SerializeGltfTextureInfo(pbr.metallicRoughnessTexture, texinfo);
+    JsonAddMember(o, "metallicRoughnessTexture", std::move(texinfo));
+  }
+
+  SerializeExtensionMap(pbr.extensions, o);
+
+  if (pbr.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", pbr.extras, o);
+  }
+}
+
+static void SerializeGltfMaterial(Material &material, json &o) {
+  if (material.name.size()) {
+    SerializeStringProperty("name", material.name, o);
+  }
+
+  // QUESTION(syoyo): Write material parameters regardless of its default value?
+
+  if (!TINYGLTF_DOUBLE_EQUAL(material.alphaCutoff, 0.5)) {
+    SerializeNumberProperty("alphaCutoff", material.alphaCutoff, o);
+  }
+
+  if (material.alphaMode.compare("OPAQUE") != 0) {
+    SerializeStringProperty("alphaMode", material.alphaMode, o);
+  }
+
+  if (material.doubleSided != false)
+    JsonAddMember(o, "doubleSided", json(material.doubleSided));
+
+  if (material.normalTexture.index > -1) {
+    json texinfo;
+    SerializeGltfNormalTextureInfo(material.normalTexture, texinfo);
+    JsonAddMember(o, "normalTexture", std::move(texinfo));
+  }
+
+  if (material.occlusionTexture.index > -1) {
+    json texinfo;
+    SerializeGltfOcclusionTextureInfo(material.occlusionTexture, texinfo);
+    JsonAddMember(o, "occlusionTexture", std::move(texinfo));
+  }
+
+  if (material.emissiveTexture.index > -1) {
+    json texinfo;
+    SerializeGltfTextureInfo(material.emissiveTexture, texinfo);
+    JsonAddMember(o, "emissiveTexture", std::move(texinfo));
+  }
+
+  std::vector<double> default_emissiveFactor = {0.0, 0.0, 0.0};
+  if (!Equals(material.emissiveFactor, default_emissiveFactor)) {
+    SerializeNumberArrayProperty<double>("emissiveFactor",
+                                         material.emissiveFactor, o);
+  }
+
+  {
+    json pbrMetallicRoughness;
+    SerializeGltfPbrMetallicRoughness(material.pbrMetallicRoughness,
+                                      pbrMetallicRoughness);
+    // Issue 204
+    // Do not serialize `pbrMetallicRoughness` if pbrMetallicRoughness has all
+    // default values(json is null). Otherwise it will serialize to
+    // `pbrMetallicRoughness : null`, which cannot be read by other glTF
+    // importers(and validators).
+    //
+    if (!JsonIsNull(pbrMetallicRoughness)) {
+      JsonAddMember(o, "pbrMetallicRoughness", std::move(pbrMetallicRoughness));
+    }
+  }
+
+#if 0  // legacy way. just for the record.
+  if (material.values.size()) {
+    json pbrMetallicRoughness;
+    SerializeParameterMap(material.values, pbrMetallicRoughness);
+    JsonAddMember(o, "pbrMetallicRoughness", std::move(pbrMetallicRoughness));
+  }
+
+  SerializeParameterMap(material.additionalValues, o);
+#else
+
+#endif
+
+  SerializeExtensionMap(material.extensions, o);
+
+  if (material.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", material.extras, o);
+  }
+}
+
+static void SerializeGltfMesh(Mesh &mesh, json &o) {
+  json primitives;
+  JsonReserveArray(primitives, mesh.primitives.size());
+  for (unsigned int i = 0; i < mesh.primitives.size(); ++i) {
+    json primitive;
+    const Primitive &gltfPrimitive = mesh.primitives[i];  // don't make a copy
+    {
+      json attributes;
+      for (auto attrIt = gltfPrimitive.attributes.begin();
+           attrIt != gltfPrimitive.attributes.end(); ++attrIt) {
+        SerializeNumberProperty<int>(attrIt->first, attrIt->second, attributes);
+      }
+
+      JsonAddMember(primitive, "attributes", std::move(attributes));
+    }
+
+    // Indicies is optional
+    if (gltfPrimitive.indices > -1) {
+      SerializeNumberProperty<int>("indices", gltfPrimitive.indices, primitive);
+    }
+    // Material is optional
+    if (gltfPrimitive.material > -1) {
+      SerializeNumberProperty<int>("material", gltfPrimitive.material,
+                                   primitive);
+    }
+    SerializeNumberProperty<int>("mode", gltfPrimitive.mode, primitive);
+
+    // Morph targets
+    if (gltfPrimitive.targets.size()) {
+      json targets;
+      JsonReserveArray(targets, gltfPrimitive.targets.size());
+      for (unsigned int k = 0; k < gltfPrimitive.targets.size(); ++k) {
+        json targetAttributes;
+        std::map<std::string, int> targetData = gltfPrimitive.targets[k];
+        for (std::map<std::string, int>::iterator attrIt = targetData.begin();
+             attrIt != targetData.end(); ++attrIt) {
+          SerializeNumberProperty<int>(attrIt->first, attrIt->second,
+                                       targetAttributes);
+        }
+        JsonPushBack(targets, std::move(targetAttributes));
+      }
+      JsonAddMember(primitive, "targets", std::move(targets));
+    }
+
+    SerializeExtensionMap(gltfPrimitive.extensions, primitive);
+
+    if (gltfPrimitive.extras.Type() != NULL_TYPE) {
+      SerializeValue("extras", gltfPrimitive.extras, primitive);
+    }
+
+    JsonPushBack(primitives, std::move(primitive));
+  }
+
+  JsonAddMember(o, "primitives", std::move(primitives));
+
+  if (mesh.weights.size()) {
+    SerializeNumberArrayProperty<double>("weights", mesh.weights, o);
+  }
+
+  if (mesh.name.size()) {
+    SerializeStringProperty("name", mesh.name, o);
+  }
+
+  SerializeExtensionMap(mesh.extensions, o);
+  if (mesh.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", mesh.extras, o);
+  }
+}
+
+static void SerializeSpotLight(SpotLight &spot, json &o) {
+  SerializeNumberProperty("innerConeAngle", spot.innerConeAngle, o);
+  SerializeNumberProperty("outerConeAngle", spot.outerConeAngle, o);
+  SerializeExtensionMap(spot.extensions, o);
+  if (spot.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", spot.extras, o);
+  }
+}
+
+static void SerializeGltfLight(Light &light, json &o) {
+  if (!light.name.empty()) SerializeStringProperty("name", light.name, o);
+  SerializeNumberProperty("intensity", light.intensity, o);
+  if (light.range > 0.0) {
+    SerializeNumberProperty("range", light.range, o);
+  }
+  SerializeNumberArrayProperty("color", light.color, o);
+  SerializeStringProperty("type", light.type, o);
+  if (light.type == "spot") {
+    json spot;
+    SerializeSpotLight(light.spot, spot);
+    JsonAddMember(o, "spot", std::move(spot));
+  }
+  SerializeExtensionMap(light.extensions, o);
+  if (light.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", light.extras, o);
+  }
+}
+
+static void SerializeGltfNode(Node &node, json &o) {
+  if (node.translation.size() > 0) {
+    SerializeNumberArrayProperty<double>("translation", node.translation, o);
+  }
+  if (node.rotation.size() > 0) {
+    SerializeNumberArrayProperty<double>("rotation", node.rotation, o);
+  }
+  if (node.scale.size() > 0) {
+    SerializeNumberArrayProperty<double>("scale", node.scale, o);
+  }
+  if (node.matrix.size() > 0) {
+    SerializeNumberArrayProperty<double>("matrix", node.matrix, o);
+  }
+  if (node.mesh != -1) {
+    SerializeNumberProperty<int>("mesh", node.mesh, o);
+  }
+
+  if (node.skin != -1) {
+    SerializeNumberProperty<int>("skin", node.skin, o);
+  }
+
+  if (node.camera != -1) {
+    SerializeNumberProperty<int>("camera", node.camera, o);
+  }
+
+  if (node.weights.size() > 0) {
+    SerializeNumberArrayProperty<double>("weights", node.weights, o);
+  }
+
+  if (node.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", node.extras, o);
+  }
+
+  SerializeExtensionMap(node.extensions, o);
+  if (!node.name.empty()) SerializeStringProperty("name", node.name, o);
+  SerializeNumberArrayProperty<int>("children", node.children, o);
+}
+
+static void SerializeGltfSampler(Sampler &sampler, json &o) {
+  if (sampler.magFilter != -1) {
+    SerializeNumberProperty("magFilter", sampler.magFilter, o);
+  }
+  if (sampler.minFilter != -1) {
+    SerializeNumberProperty("minFilter", sampler.minFilter, o);
+  }
+  SerializeNumberProperty("wrapR", sampler.wrapR, o);
+  SerializeNumberProperty("wrapS", sampler.wrapS, o);
+  SerializeNumberProperty("wrapT", sampler.wrapT, o);
+
+  if (sampler.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", sampler.extras, o);
+  }
+}
+
+static void SerializeGltfOrthographicCamera(const OrthographicCamera &camera,
+                                            json &o) {
+  SerializeNumberProperty("zfar", camera.zfar, o);
+  SerializeNumberProperty("znear", camera.znear, o);
+  SerializeNumberProperty("xmag", camera.xmag, o);
+  SerializeNumberProperty("ymag", camera.ymag, o);
+
+  if (camera.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", camera.extras, o);
+  }
+}
+
+static void SerializeGltfPerspectiveCamera(const PerspectiveCamera &camera,
+                                           json &o) {
+  SerializeNumberProperty("zfar", camera.zfar, o);
+  SerializeNumberProperty("znear", camera.znear, o);
+  if (camera.aspectRatio > 0) {
+    SerializeNumberProperty("aspectRatio", camera.aspectRatio, o);
+  }
+
+  if (camera.yfov > 0) {
+    SerializeNumberProperty("yfov", camera.yfov, o);
+  }
+
+  if (camera.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", camera.extras, o);
+  }
+}
+
+static void SerializeGltfCamera(const Camera &camera, json &o) {
+  SerializeStringProperty("type", camera.type, o);
+  if (!camera.name.empty()) {
+    SerializeStringProperty("name", camera.name, o);
+  }
+
+  if (camera.type.compare("orthographic") == 0) {
+    json orthographic;
+    SerializeGltfOrthographicCamera(camera.orthographic, orthographic);
+    JsonAddMember(o, "orthographic", std::move(orthographic));
+  } else if (camera.type.compare("perspective") == 0) {
+    json perspective;
+    SerializeGltfPerspectiveCamera(camera.perspective, perspective);
+    JsonAddMember(o, "perspective", std::move(perspective));
+  } else {
+    // ???
+  }
+
+  if (camera.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", camera.extras, o);
+  }
+  SerializeExtensionMap(camera.extensions, o);
+}
+
+static void SerializeGltfScene(Scene &scene, json &o) {
+  SerializeNumberArrayProperty<int>("nodes", scene.nodes, o);
+
+  if (scene.name.size()) {
+    SerializeStringProperty("name", scene.name, o);
+  }
+  if (scene.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", scene.extras, o);
+  }
+  SerializeExtensionMap(scene.extensions, o);
+}
+
+static void SerializeGltfSkin(Skin &skin, json &o) {
+  if (skin.inverseBindMatrices != -1)
+    SerializeNumberProperty("inverseBindMatrices", skin.inverseBindMatrices, o);
+
+  SerializeNumberArrayProperty<int>("joints", skin.joints, o);
+  SerializeNumberProperty("skeleton", skin.skeleton, o);
+  if (skin.name.size()) {
+    SerializeStringProperty("name", skin.name, o);
+  }
+}
+
+static void SerializeGltfTexture(Texture &texture, json &o) {
+  if (texture.sampler > -1) {
+    SerializeNumberProperty("sampler", texture.sampler, o);
+  }
+  if (texture.source > -1) {
+    SerializeNumberProperty("source", texture.source, o);
+  }
+  if (texture.name.size()) {
+    SerializeStringProperty("name", texture.name, o);
+  }
+  if (texture.extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", texture.extras, o);
+  }
+  SerializeExtensionMap(texture.extensions, o);
+}
+
+///
+/// Serialize all properties except buffers and images.
+///
+static void SerializeGltfModel(Model *model, json &o) {
+  // ACCESSORS
+  if (model->accessors.size()) {
+    json accessors;
+    JsonReserveArray(accessors, model->accessors.size());
+    for (unsigned int i = 0; i < model->accessors.size(); ++i) {
+      json accessor;
+      SerializeGltfAccessor(model->accessors[i], accessor);
+      JsonPushBack(accessors, std::move(accessor));
+    }
+    JsonAddMember(o, "accessors", std::move(accessors));
+  }
+
+  // ANIMATIONS
+  if (model->animations.size()) {
+    json animations;
+    JsonReserveArray(animations, model->animations.size());
+    for (unsigned int i = 0; i < model->animations.size(); ++i) {
+      if (model->animations[i].channels.size()) {
+        json animation;
+        SerializeGltfAnimation(model->animations[i], animation);
+        JsonPushBack(animations, std::move(animation));
+      }
+    }
+
+    JsonAddMember(o, "animations", std::move(animations));
+  }
+
+  // ASSET
+  json asset;
+  SerializeGltfAsset(model->asset, asset);
+  JsonAddMember(o, "asset", std::move(asset));
+
+  // BUFFERVIEWS
+  if (model->bufferViews.size()) {
+    json bufferViews;
+    JsonReserveArray(bufferViews, model->bufferViews.size());
+    for (unsigned int i = 0; i < model->bufferViews.size(); ++i) {
+      json bufferView;
+      SerializeGltfBufferView(model->bufferViews[i], bufferView);
+      JsonPushBack(bufferViews, std::move(bufferView));
+    }
+    JsonAddMember(o, "bufferViews", std::move(bufferViews));
+  }
+
+  // Extensions required
+  if (model->extensionsRequired.size()) {
+    SerializeStringArrayProperty("extensionsRequired",
+                                 model->extensionsRequired, o);
+  }
+
+  // MATERIALS
+  if (model->materials.size()) {
+    json materials;
+    JsonReserveArray(materials, model->materials.size());
+    for (unsigned int i = 0; i < model->materials.size(); ++i) {
+      json material;
+      SerializeGltfMaterial(model->materials[i], material);
+      JsonPushBack(materials, std::move(material));
+    }
+    JsonAddMember(o, "materials", std::move(materials));
+  }
+
+  // MESHES
+  if (model->meshes.size()) {
+    json meshes;
+    JsonReserveArray(meshes, model->meshes.size());
+    for (unsigned int i = 0; i < model->meshes.size(); ++i) {
+      json mesh;
+      SerializeGltfMesh(model->meshes[i], mesh);
+      JsonPushBack(meshes, std::move(mesh));
+    }
+    JsonAddMember(o, "meshes", std::move(meshes));
+  }
+
+  // NODES
+  if (model->nodes.size()) {
+    json nodes;
+    JsonReserveArray(nodes, model->nodes.size());
+    for (unsigned int i = 0; i < model->nodes.size(); ++i) {
+      json node;
+      SerializeGltfNode(model->nodes[i], node);
+      JsonPushBack(nodes, std::move(node));
+    }
+    JsonAddMember(o, "nodes", std::move(nodes));
+  }
+
+  // SCENE
+  if (model->defaultScene > -1) {
+    SerializeNumberProperty<int>("scene", model->defaultScene, o);
+  }
+
+  // SCENES
+  if (model->scenes.size()) {
+    json scenes;
+    JsonReserveArray(scenes, model->scenes.size());
+    for (unsigned int i = 0; i < model->scenes.size(); ++i) {
+      json currentScene;
+      SerializeGltfScene(model->scenes[i], currentScene);
+      JsonPushBack(scenes, std::move(currentScene));
+    }
+    JsonAddMember(o, "scenes", std::move(scenes));
+  }
+
+  // SKINS
+  if (model->skins.size()) {
+    json skins;
+    JsonReserveArray(skins, model->skins.size());
+    for (unsigned int i = 0; i < model->skins.size(); ++i) {
+      json skin;
+      SerializeGltfSkin(model->skins[i], skin);
+      JsonPushBack(skins, std::move(skin));
+    }
+    JsonAddMember(o, "skins", std::move(skins));
+  }
+
+  // TEXTURES
+  if (model->textures.size()) {
+    json textures;
+    JsonReserveArray(textures, model->textures.size());
+    for (unsigned int i = 0; i < model->textures.size(); ++i) {
+      json texture;
+      SerializeGltfTexture(model->textures[i], texture);
+      JsonPushBack(textures, std::move(texture));
+    }
+    JsonAddMember(o, "textures", std::move(textures));
+  }
+
+  // SAMPLERS
+  if (model->samplers.size()) {
+    json samplers;
+    JsonReserveArray(samplers, model->samplers.size());
+    for (unsigned int i = 0; i < model->samplers.size(); ++i) {
+      json sampler;
+      SerializeGltfSampler(model->samplers[i], sampler);
+      JsonPushBack(samplers, std::move(sampler));
+    }
+    JsonAddMember(o, "samplers", std::move(samplers));
+  }
+
+  // CAMERAS
+  if (model->cameras.size()) {
+    json cameras;
+    JsonReserveArray(cameras, model->cameras.size());
+    for (unsigned int i = 0; i < model->cameras.size(); ++i) {
+      json camera;
+      SerializeGltfCamera(model->cameras[i], camera);
+      JsonPushBack(cameras, std::move(camera));
+    }
+    JsonAddMember(o, "cameras", std::move(cameras));
+  }
+
+  // EXTENSIONS
+  SerializeExtensionMap(model->extensions, o);
+
+  auto extensionsUsed = model->extensionsUsed;
+
+  // LIGHTS as KHR_lights_punctual
+  if (model->lights.size()) {
+    json lights;
+    JsonReserveArray(lights, model->lights.size());
+    for (unsigned int i = 0; i < model->lights.size(); ++i) {
+      json light;
+      SerializeGltfLight(model->lights[i], light);
+      JsonPushBack(lights, std::move(light));
+    }
+    json khr_lights_cmn;
+    JsonAddMember(khr_lights_cmn, "lights", std::move(lights));
+    json ext_j;
+
+    {
+      json_const_iterator it;
+      if (FindMember(o, "extensions", it)) {
+        JsonAssign(ext_j, GetValue(it));
+      }
+    }
+
+    JsonAddMember(ext_j, "KHR_lights_punctual", std::move(khr_lights_cmn));
+
+    JsonAddMember(o, "extensions", std::move(ext_j));
+
+    // Also add "KHR_lights_punctual" to `extensionsUsed`
+    {
+      auto has_khr_lights_punctual =
+          std::find_if(extensionsUsed.begin(), extensionsUsed.end(),
+                       [](const std::string &s) {
+                         return (s.compare("KHR_lights_punctual") == 0);
+                       });
+
+      if (has_khr_lights_punctual == extensionsUsed.end()) {
+        extensionsUsed.push_back("KHR_lights_punctual");
+      }
+    }
+  }
+
+  // Extensions used
+  if (model->extensionsUsed.size()) {
+    SerializeStringArrayProperty("extensionsUsed", extensionsUsed, o);
+  }
+
+  // EXTRAS
+  if (model->extras.Type() != NULL_TYPE) {
+    SerializeValue("extras", model->extras, o);
+  }
+}
+
+static bool WriteGltfStream(std::ostream &stream, const std::string &content) {
+  stream << content << std::endl;
+  return true;
+}
+
+static bool WriteGltfFile(const std::string &output,
+                          const std::string &content) {
+#ifdef _WIN32
+#if defined(_MSC_VER)
+  std::ofstream gltfFile(UTF8ToWchar(output).c_str());
+#elif defined(__GLIBCXX__)
+  int file_descriptor = _wopen(UTF8ToWchar(output).c_str(),
+                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
+  __gnu_cxx::stdio_filebuf<char> wfile_buf(
+      file_descriptor, std::ios_base::out | std::ios_base::binary);
+  std::ostream gltfFile(&wfile_buf);
+  if (!wfile_buf.is_open()) return false;
+#else
+  std::ofstream gltfFile(output.c_str());
+  if (!gltfFile.is_open()) return false;
+#endif
+#else
+  std::ofstream gltfFile(output.c_str());
+  if (!gltfFile.is_open()) return false;
+#endif
+  return WriteGltfStream(gltfFile, content);
+}
+
+static void WriteBinaryGltfStream(std::ostream &stream,
+                                  const std::string &content,
+                                  const std::vector<unsigned char> &binBuffer) {
+  const std::string header = "glTF";
+  const int version = 2;
+
+  // https://stackoverflow.com/questions/3407012/c-rounding-up-to-the-nearest-multiple-of-a-number
+  auto roundUp = [](uint32_t numToRound, uint32_t multiple) {
+    if (multiple == 0) return numToRound;
+
+    uint32_t remainder = numToRound % multiple;
+    if (remainder == 0) return numToRound;
+
+    return numToRound + multiple - remainder;
+  };
+
+  const uint32_t padding_size =
+      roundUp(uint32_t(content.size()), 4) - uint32_t(content.size());
+
+  // 12 bytes for header, JSON content length, 8 bytes for JSON chunk info.
+  // Chunk data must be located at 4-byte boundary.
+  const uint32_t length =
+      12 + 8 + roundUp(uint32_t(content.size()), 4) +
+      (binBuffer.size() ? (8 + roundUp(uint32_t(binBuffer.size()), 4)) : 0);
+
+  stream.write(header.c_str(), std::streamsize(header.size()));
+  stream.write(reinterpret_cast<const char *>(&version), sizeof(version));
+  stream.write(reinterpret_cast<const char *>(&length), sizeof(length));
+
+  // JSON chunk info, then JSON data
+  const uint32_t model_length = uint32_t(content.size()) + padding_size;
+  const uint32_t model_format = 0x4E4F534A;
+  stream.write(reinterpret_cast<const char *>(&model_length),
+               sizeof(model_length));
+  stream.write(reinterpret_cast<const char *>(&model_format),
+               sizeof(model_format));
+  stream.write(content.c_str(), std::streamsize(content.size()));
+
+  // Chunk must be multiplies of 4, so pad with spaces
+  if (padding_size > 0) {
+    const std::string padding = std::string(size_t(padding_size), ' ');
+    stream.write(padding.c_str(), std::streamsize(padding.size()));
+  }
+  if (binBuffer.size() > 0) {
+    const uint32_t bin_padding_size =
+        roundUp(uint32_t(binBuffer.size()), 4) - uint32_t(binBuffer.size());
+    // BIN chunk info, then BIN data
+    const uint32_t bin_length = uint32_t(binBuffer.size()) + bin_padding_size;
+    const uint32_t bin_format = 0x004e4942;
+    stream.write(reinterpret_cast<const char *>(&bin_length),
+                 sizeof(bin_length));
+    stream.write(reinterpret_cast<const char *>(&bin_format),
+                 sizeof(bin_format));
+    stream.write(reinterpret_cast<const char *>(binBuffer.data()),
+                 std::streamsize(binBuffer.size()));
+    // Chunksize must be multiplies of 4, so pad with zeroes
+    if (bin_padding_size > 0) {
+      const std::vector<unsigned char> padding =
+          std::vector<unsigned char>(size_t(bin_padding_size), 0);
+      stream.write(reinterpret_cast<const char *>(padding.data()),
+                   std::streamsize(padding.size()));
+    }
+  }
+}
+
+static void WriteBinaryGltfFile(const std::string &output,
+                                const std::string &content,
+                                const std::vector<unsigned char> &binBuffer) {
+#ifdef _WIN32
+#if defined(_MSC_VER)
+  std::ofstream gltfFile(UTF8ToWchar(output).c_str(), std::ios::binary);
+#elif defined(__GLIBCXX__)
+  int file_descriptor = _wopen(UTF8ToWchar(output).c_str(),
+                               _O_CREAT | _O_WRONLY | _O_TRUNC | _O_BINARY);
+  __gnu_cxx::stdio_filebuf<char> wfile_buf(
+      file_descriptor, std::ios_base::out | std::ios_base::binary);
+  std::ostream gltfFile(&wfile_buf);
+#else
+  std::ofstream gltfFile(output.c_str(), std::ios::binary);
+#endif
+#else
+  std::ofstream gltfFile(output.c_str(), std::ios::binary);
+#endif
+  WriteBinaryGltfStream(gltfFile, content, binBuffer);
+}
+
+bool TinyGLTF::WriteGltfSceneToStream(Model *model, std::ostream &stream,
+                                      bool prettyPrint = true,
+                                      bool writeBinary = false) {
+  JsonDocument output;
+
+  /// Serialize all properties except buffers and images.
+  SerializeGltfModel(model, output);
+
+  // BUFFERS
+  std::vector<unsigned char> binBuffer;
+  if (model->buffers.size()) {
+    json buffers;
+    JsonReserveArray(buffers, model->buffers.size());
+    for (unsigned int i = 0; i < model->buffers.size(); ++i) {
+      json buffer;
+      if (writeBinary && i == 0 && model->buffers[i].uri.empty()) {
+        SerializeGltfBufferBin(model->buffers[i], buffer, binBuffer);
+      } else {
+        SerializeGltfBuffer(model->buffers[i], buffer);
+      }
+      JsonPushBack(buffers, std::move(buffer));
+    }
+    JsonAddMember(output, "buffers", std::move(buffers));
+  }
+
+  // IMAGES
+  if (model->images.size()) {
+    json images;
+    JsonReserveArray(images, model->images.size());
+    for (unsigned int i = 0; i < model->images.size(); ++i) {
+      json image;
+
+      std::string dummystring = "";
+      // UpdateImageObject need baseDir but only uses it if embeddedImages is
+      // enabled, since we won't write separate images when writing to a stream
+      // we
+      UpdateImageObject(model->images[i], dummystring, int(i), false,
+                        &this->WriteImageData, this->write_image_user_data_);
+      SerializeGltfImage(model->images[i], image);
+      JsonPushBack(images, std::move(image));
+    }
+    JsonAddMember(output, "images", std::move(images));
+  }
+
+  if (writeBinary) {
+    WriteBinaryGltfStream(stream, JsonToString(output), binBuffer);
+  } else {
+    WriteGltfStream(stream, JsonToString(output, prettyPrint ? 2 : -1));
+  }
+
+  return true;
+}
+
+bool TinyGLTF::WriteGltfSceneToFile(Model *model, const std::string &filename,
+                                    bool embedImages = false,
+                                    bool embedBuffers = false,
+                                    bool prettyPrint = true,
+                                    bool writeBinary = false) {
+  JsonDocument output;
+  std::string defaultBinFilename = GetBaseFilename(filename);
+  std::string defaultBinFileExt = ".bin";
+  std::string::size_type pos =
+      defaultBinFilename.rfind('.', defaultBinFilename.length());
+
+  if (pos != std::string::npos) {
+    defaultBinFilename = defaultBinFilename.substr(0, pos);
+  }
+  std::string baseDir = GetBaseDir(filename);
+  if (baseDir.empty()) {
+    baseDir = "./";
+  }
+  /// Serialize all properties except buffers and images.
+  SerializeGltfModel(model, output);
+
+  // BUFFERS
+  std::vector<std::string> usedUris;
+  std::vector<unsigned char> binBuffer;
+  if (model->buffers.size()) {
+    json buffers;
+    JsonReserveArray(buffers, model->buffers.size());
+    for (unsigned int i = 0; i < model->buffers.size(); ++i) {
+      json buffer;
+      if (writeBinary && i == 0 && model->buffers[i].uri.empty()) {
+        SerializeGltfBufferBin(model->buffers[i], buffer, binBuffer);
+      } else if (embedBuffers) {
+        SerializeGltfBuffer(model->buffers[i], buffer);
+      } else {
+        std::string binSavePath;
+        std::string binUri;
+        if (!model->buffers[i].uri.empty() &&
+            !IsDataURI(model->buffers[i].uri)) {
+          binUri = model->buffers[i].uri;
+        } else {
+          binUri = defaultBinFilename + defaultBinFileExt;
+          bool inUse = true;
+          int numUsed = 0;
+          while (inUse) {
+            inUse = false;
+            for (const std::string &usedName : usedUris) {
+              if (binUri.compare(usedName) != 0) continue;
+              inUse = true;
+              binUri = defaultBinFilename + std::to_string(numUsed++) +
+                       defaultBinFileExt;
+              break;
+            }
+          }
+        }
+        usedUris.push_back(binUri);
+        binSavePath = JoinPath(baseDir, binUri);
+        if (!SerializeGltfBuffer(model->buffers[i], buffer, binSavePath,
+                                 binUri)) {
+          return false;
+        }
+      }
+      JsonPushBack(buffers, std::move(buffer));
+    }
+    JsonAddMember(output, "buffers", std::move(buffers));
+  }
+
+  // IMAGES
+  if (model->images.size()) {
+    json images;
+    JsonReserveArray(images, model->images.size());
+    for (unsigned int i = 0; i < model->images.size(); ++i) {
+      json image;
+
+      UpdateImageObject(model->images[i], baseDir, int(i), embedImages,
+                        &this->WriteImageData, this->write_image_user_data_);
+      SerializeGltfImage(model->images[i], image);
+      JsonPushBack(images, std::move(image));
+    }
+    JsonAddMember(output, "images", std::move(images));
+  }
+
+  if (writeBinary) {
+    WriteBinaryGltfFile(filename, JsonToString(output), binBuffer);
+  } else {
+    WriteGltfFile(filename, JsonToString(output, (prettyPrint ? 2 : -1)));
+  }
+
+  return true;
+}
+
+}  // namespace tinygltf
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+#endif  // TINYGLTF_IMPLEMENTATION
diff --git a/engine/inc/uf/ext/gltf/gltf.h b/engine/inc/uf/ext/gltf/gltf.h
new file mode 100644
index 00000000..21c660d9
--- /dev/null
+++ b/engine/inc/uf/ext/gltf/gltf.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <uf/engine/object/object.h>
+
+namespace ext {
+	namespace gltf {
+		enum LoadMode {
+			GENERATE_NORMALS 		= 0x1 << 0,
+			APPLY_TRANSFORMS 		= 0x1 << 1,
+			SEPARATE_MESHES 		= 0x1 << 2,
+			RENDER 					= 0x1 << 3,
+			COLLISION 				= 0x1 << 4,
+			AABB 					= 0x1 << 5,
+		};
+		bool UF_API load( uf::Object&, const std::string&, uint8_t = LoadMode::GENERATE_NORMALS | LoadMode::RENDER );
+	}
+}
\ No newline at end of file
diff --git a/engine/inc/uf/ext/openvr/openvr.h b/engine/inc/uf/ext/openvr/openvr.h
index 0f059f45..769b3cd5 100644
--- a/engine/inc/uf/ext/openvr/openvr.h
+++ b/engine/inc/uf/ext/openvr/openvr.h
@@ -35,6 +35,7 @@ namespace ext {
 		extern UF_API float width, height;
 		extern UF_API bool enabled;
 		extern UF_API bool swapEyes;
+		extern UF_API uint8_t dominantEye;
 
 		bool UF_API initialize( int stage = 0 );
 		void UF_API tick();
diff --git a/engine/inc/uf/ext/vulkan/rendertarget.h b/engine/inc/uf/ext/vulkan/rendertarget.h
index 87ec8bf1..7f51e1a7 100644
--- a/engine/inc/uf/ext/vulkan/rendertarget.h
+++ b/engine/inc/uf/ext/vulkan/rendertarget.h
@@ -16,6 +16,7 @@ namespace ext {
 				VkImageView view;
 				VmaAllocation allocation;
 				VmaAllocationInfo allocationInfo;
+				VkPipelineColorBlendAttachmentState blendState;
 			} Attachment;
 			std::vector<Attachment> attachments;
 
@@ -38,7 +39,7 @@ namespace ext {
 			void initialize( Device& device );
 			void destroy();
 			void addPass( VkPipelineStageFlags, VkAccessFlags, const std::vector<size_t>&, const std::vector<size_t>&, size_t );
-			size_t attach( VkFormat format, VkImageUsageFlags usage, VkImageLayout layout, Attachment* attachment = NULL );
+			size_t attach( VkFormat format, VkImageUsageFlags usage, VkImageLayout layout, bool blend = false, Attachment* attachment = NULL );
 		};
 	}
 }
\ No newline at end of file
diff --git a/engine/inc/uf/ext/vulkan/texture.h b/engine/inc/uf/ext/vulkan/texture.h
index cb99af6f..3cbc6d5f 100644
--- a/engine/inc/uf/ext/vulkan/texture.h
+++ b/engine/inc/uf/ext/vulkan/texture.h
@@ -11,10 +11,29 @@ namespace ext {
 			Device* device = NULL;
 
 			VkSampler sampler;
-			VkDescriptorImageInfo descriptor;
-			VkFilter filter = VK_FILTER_LINEAR;
+			struct {
+				struct {
+					VkFilter min = VK_FILTER_LINEAR;
+					VkFilter mag = VK_FILTER_LINEAR;
+				} filter;
+				struct {
+					VkSamplerAddressMode u = VK_SAMPLER_ADDRESS_MODE_REPEAT, v = VK_SAMPLER_ADDRESS_MODE_REPEAT, w = VK_SAMPLER_ADDRESS_MODE_REPEAT;
+				} addressMode;
+				struct {
+					VkSamplerMipmapMode mode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
+					float lodBias = 0.0f;
+				} mip;
+				VkCompareOp compareOp = VK_COMPARE_OP_NEVER;
+				struct {
+					float min = 0.0f;
+					float max = 0.0f;
+				} lod;
+				float maxAnisotropy;
 
-			void initialize( Device& device, VkFilter filter = VK_FILTER_LINEAR );
+				VkDescriptorImageInfo info;
+			} descriptor;
+
+			void initialize( Device& device );
 			void destroy();
 		};
 		struct UF_API Texture {
@@ -59,6 +78,7 @@ namespace ext {
 			);
 		};
 		struct UF_API Texture2D : public Texture {
+			static Texture2D empty;
 			void loadFromFile(
 				std::string filename, 
 				VkFormat format = VK_FORMAT_R8G8B8A8_UNORM,
@@ -99,7 +119,6 @@ namespace ext {
 				uint32_t texHeight,
 				Device& device,
 				VkQueue copyQueue,
-				VkFilter filter = VK_FILTER_LINEAR,
 				VkImageUsageFlags imageUsageFlags = VK_IMAGE_USAGE_SAMPLED_BIT,
 				VkImageLayout imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL
 			);
diff --git a/engine/inc/uf/ext/vulkan/vulkan.h b/engine/inc/uf/ext/vulkan/vulkan.h
index d2ecbfd3..06de000f 100644
--- a/engine/inc/uf/ext/vulkan/vulkan.h
+++ b/engine/inc/uf/ext/vulkan/vulkan.h
@@ -43,6 +43,8 @@ namespace ext {
 		extern UF_API uint32_t height;
 
 		extern UF_API bool validation;
+		extern UF_API std::vector<std::string> validationFilters;
+		extern UF_API std::vector<std::string> requestedDeviceFeatures;
 		extern UF_API Device device;
 		typedef VmaAllocator Allocator;
 		extern UF_API Allocator allocator;
diff --git a/engine/inc/uf/utils/camera/camera.h b/engine/inc/uf/utils/camera/camera.h
index 29ec2042..598ecd5e 100644
--- a/engine/inc/uf/utils/camera/camera.h
+++ b/engine/inc/uf/utils/camera/camera.h
@@ -22,6 +22,7 @@ namespace uf {
 			} perspective;
 			int mode;
 			pod::Vector3 offset;
+			bool stereoscopic = false;
 		} m_settings;
 		struct {
 			struct {
@@ -38,6 +39,7 @@ namespace uf {
 		Camera( const Camera& copy );
 */
 		bool modified() const;
+		void setStereoscopic( bool );
 		pod::Transform<>& getTransform();
 		const pod::Transform<>& getTransform() const;
 
diff --git a/engine/inc/uf/utils/image/image.h b/engine/inc/uf/utils/image/image.h
index 49073e29..4a83ca82 100644
--- a/engine/inc/uf/utils/image/image.h
+++ b/engine/inc/uf/utils/image/image.h
@@ -35,7 +35,7 @@ namespace uf {
 		~Image();
 		void clear(); 																			// empties pixel container
 	// 	Getters
-		void loadFromBuffer( const Image::pixel_t::type_t* pointer, const pod::Vector2ui& size, std::size_t bpp, std::size_t channels );
+		void loadFromBuffer( const Image::pixel_t::type_t* pointer, const pod::Vector2ui& size, std::size_t bpp, std::size_t channels, bool flip = false );
 		void loadFromBuffer( const Image::container_t& container, const pod::Vector2ui& size, std::size_t bpp, std::size_t channels, bool flip = false );
 		std::string getFilename() const;
 		Image::container_t& getPixels();
diff --git a/engine/inc/uf/utils/math/collision.h b/engine/inc/uf/utils/math/collision.h
index abd9f319..7db8db80 100644
--- a/engine/inc/uf/utils/math/collision.h
+++ b/engine/inc/uf/utils/math/collision.h
@@ -2,157 +2,29 @@
 
 #include <uf/config.h>
 
-#include <uf/utils/math/vector.h>
-#include <functional>
+#include "./collision/gjk.h"
+#include "./collision/boundingbox.h"
+#include "./collision/sphere.h"
+#include "./collision/mesh.h"
+#include <vector>
 
-// #include <uf/gl/mesh/mesh.h>
-namespace pod {
-	struct UF_API Simplex {
-	public:
-		struct UF_API SupportPoint {
-			pod::Vector3 a, b, v;
-			bool operator==( const pod::Simplex::SupportPoint& r ) const {
-				return v == r.v;
-			}
-			pod::Vector3 operator-( const pod::Simplex::SupportPoint& r ) const {
-				return v - r.v;
-			}
-			pod::Vector3 operator*( float r ) const {
-				return v * r;
-			}
-			pod::Vector3 operator-( const pod::Vector3& r ) const {
-				return v - r;
-			}
-			float dot( const pod::Vector3& r ) const {
-				return uf::vector::dot(v, r);
-			}
-			pod::Vector3 cross( const pod::Simplex::SupportPoint& r ) const {
-				return uf::vector::cross(v, r.v);
-			}
-			pod::Vector3 cross( const pod::Vector3& r ) const {
-				return uf::vector::cross(v, r);
-			}
-		};
-		int size = 0;
-		pod::Simplex::SupportPoint b, c, d;
-	/*	pod::Vector3 b, c, d;
-		Simplex( const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3() );
-		void add( const pod::Vector3& );
-		void set( const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3() );
-	*/
-	};
-}
 namespace uf {
 	class UF_API Collider {
+	public:
+		typedef std::vector<pod::Collider*> container_t;
 	protected:
+		uf::Collider::container_t m_container;
 	public:
-		struct UF_API Manifold {
-			const uf::Collider* a;
-			const uf::Collider* b;
-			pod::Vector3 normal;
-			float depth;
-			bool colliding;
-
-			Manifold() {
-				this->normal = pod::Vector3{0.0f, 0.0f, 0.0f};
-				this->depth = -0.1f;
-				this->colliding = false;
-			}
-			Manifold( const uf::Collider& a, const uf::Collider& b ) {
-				this->a = &a;
-				this->b = &b;
-				this->normal = pod::Vector3{0.0f, 0.0f, 0.0f};
-				this->depth = -0.1f;
-				this->colliding = false;
-			}
-			Manifold( const uf::Collider& a, const uf::Collider& b, const pod::Vector3& normal, float depth, bool colliding ) {
-				this->a = &a;
-				this->b = &b;
-				this->normal = normal;
-				this->depth = depth;
-				this->colliding = colliding;
-			}
-		};
-		virtual ~Collider();
-		virtual std::string type() const;
-		virtual pod::Vector3* expand() const = 0;
-		virtual pod::Vector3 support( const pod::Vector3& ) const = 0;
-		virtual uf::Collider::Manifold intersects( const uf::Collider& ) const;
-	};
-
-	class UF_API AABBox : public uf::Collider {
-	protected:
-		pod::Vector3 m_origin;
-		pod::Vector3 m_corner;
-	public:
-		AABBox( const pod::Vector3&, const pod::Vector3& );
-		virtual std::string type() const;
-		virtual pod::Vector3* expand() const;
-		virtual pod::Vector3 support( const pod::Vector3& ) const;
-		virtual uf::Collider::Manifold intersects( const uf::AABBox& ) const;
-	};
-	class UF_API SphereCollider : public uf::Collider {
-	protected:
-		float m_radius;
-		pod::Vector3 m_origin;
-	public:
-		SphereCollider( float = 1.0f, const pod::Vector3& = pod::Vector3{} );
-
-		float getRadius() const;
-		const pod::Vector3& getOrigin() const;
-		
-		void setRadius( float = 1.0f );
-		void setOrigin( const pod::Vector3& );
-
-		virtual std::string type() const;
-		virtual pod::Vector3* expand() const;
-		virtual pod::Vector3 support( const pod::Vector3& ) const;
-		virtual uf::Collider::Manifold intersects( const uf::SphereCollider& ) const;
-	};
-
-	class UF_API ModularCollider : public uf::Collider {
-	public:
-		typedef std::function<pod::Vector3*()> function_expand_t;
-		typedef std::function<pod::Vector3(const pod::Vector3&)> function_support_t;
-	protected:
-		uint m_len;
-		pod::Vector3* m_container;
-
-		bool m_should_free;
-
-		uf::ModularCollider::function_expand_t m_function_expand;
-		uf::ModularCollider::function_support_t m_function_support;
-	public:
-		ModularCollider( uint len = 0, pod::Vector3* = NULL, bool = false, const uf::ModularCollider::function_expand_t& = NULL, const uf::ModularCollider::function_support_t& = NULL );
-		~ModularCollider();
-		
-		void setExpand( const uf::ModularCollider::function_expand_t& = NULL );
-		void setSupport( const uf::ModularCollider::function_support_t& = NULL );
-		
-		pod::Vector3* getContainer();
-		uint getSize() const;
-		void setContainer( pod::Vector3*, uint );
-
-		virtual std::string type() const;
-		virtual pod::Vector3* expand() const;
-		virtual pod::Vector3 support( const pod::Vector3& ) const;
-	};
-	class UF_API CollisionBody {
-	public:
-		typedef std::vector<uf::Collider*> container_t;
-	protected:
-		uf::CollisionBody::container_t m_container;
-	public:
-		~CollisionBody();
+		~Collider();
 		void clear();
 
-		void add( uf::Collider* );
-		uf::CollisionBody::container_t& getContainer();
-		const uf::CollisionBody::container_t& getContainer() const;
+		void add( pod::Collider* );
+		uf::Collider::container_t& getContainer();
+		const uf::Collider::container_t& getContainer() const;
 		
 		std::size_t getSize() const;
 
-		std::vector<uf::Collider::Manifold> intersects( const uf::CollisionBody& ) const;
-		std::vector<uf::Collider::Manifold> intersects( const uf::Collider& ) const;
+		std::vector<pod::Collider::Manifold> intersects( const uf::Collider&, bool = false ) const;
+		std::vector<pod::Collider::Manifold> intersects( const pod::Collider&, bool = false ) const;
 	};
 }
\ No newline at end of file
diff --git a/engine/inc/uf/utils/math/collision/boundingbox.h b/engine/inc/uf/utils/math/collision/boundingbox.h
new file mode 100644
index 00000000..097495e8
--- /dev/null
+++ b/engine/inc/uf/utils/math/collision/boundingbox.h
@@ -0,0 +1,27 @@
+#pragma once
+
+#include "gjk.h"
+
+namespace uf {
+	class UF_API BoundingBox : public pod::Collider {
+	protected:
+		pod::Vector3 m_origin;
+		pod::Vector3 m_corner;
+	public:
+		BoundingBox( const pod::Vector3& = {}, const pod::Vector3& = {} );
+		
+		const pod::Vector3& getOrigin() const;
+		const pod::Vector3& getCorner() const;
+		void setOrigin( const pod::Vector3& );
+		void setCorner( const pod::Vector3& );
+		
+		pod::Vector3 min() const;
+		pod::Vector3 max() const;
+		pod::Vector3 closest( const pod::Vector3f& ) const;
+
+		virtual std::string type() const;
+		virtual pod::Vector3* expand() const;
+		virtual pod::Vector3 support( const pod::Vector3& ) const;
+		virtual pod::Collider::Manifold intersects( const uf::BoundingBox& ) const;
+	};
+}
\ No newline at end of file
diff --git a/engine/inc/uf/utils/math/collision/gjk.h b/engine/inc/uf/utils/math/collision/gjk.h
new file mode 100644
index 00000000..aeaebdf5
--- /dev/null
+++ b/engine/inc/uf/utils/math/collision/gjk.h
@@ -0,0 +1,88 @@
+#pragma once
+
+#include <uf/config.h>
+
+#include <uf/utils/math/vector.h>
+#include <uf/utils/math/transform.h>
+
+namespace pod {
+	struct UF_API Simplex {
+	public:
+		struct UF_API SupportPoint {
+			pod::Vector3 a, b, v;
+			bool operator==( const pod::Simplex::SupportPoint& r ) const {
+				return v == r.v;
+			}
+			pod::Vector3 operator-( const pod::Simplex::SupportPoint& r ) const {
+				return v - r.v;
+			}
+			pod::Vector3 operator*( float r ) const {
+				return v * r;
+			}
+			pod::Vector3 operator-( const pod::Vector3& r ) const {
+				return v - r;
+			}
+			float dot( const pod::Vector3& r ) const {
+				return uf::vector::dot(v, r);
+			}
+			pod::Vector3 cross( const pod::Simplex::SupportPoint& r ) const {
+				return uf::vector::cross(v, r.v);
+			}
+			pod::Vector3 cross( const pod::Vector3& r ) const {
+				return uf::vector::cross(v, r);
+			}
+		};
+		int size = 0;
+		pod::Simplex::SupportPoint b, c, d;
+	/*	
+		pod::Vector3 b, c, d;
+		Simplex( const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3() );
+		void add( const pod::Vector3& );
+		void set( const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3(), const pod::Vector3& = pod::Vector3() );
+	*/
+	};
+}
+namespace pod {
+	class UF_API Collider {
+	protected:
+		pod::Transform<> m_transform;
+	public:
+		struct UF_API Manifold {
+			const pod::Collider* a;
+			const pod::Collider* b;
+			pod::Vector3 normal;
+			float depth;
+			bool colliding;
+
+			Manifold() {
+				this->normal = pod::Vector3{0.0f, 0.0f, 0.0f};
+				this->depth = -0.1f;
+				this->colliding = false;
+			}
+			Manifold( const pod::Collider& a, const pod::Collider& b ) {
+				this->a = &a;
+				this->b = &b;
+				this->normal = pod::Vector3{0.0f, 0.0f, 0.0f};
+				this->depth = -0.1f;
+				this->colliding = false;
+			}
+			Manifold( const pod::Collider& a, const pod::Collider& b, const pod::Vector3& normal, float depth, bool colliding ) {
+				this->a = &a;
+				this->b = &b;
+				this->normal = normal;
+				this->depth = depth;
+				this->colliding = colliding;
+			}
+		};
+		virtual ~Collider();
+		virtual std::string type() const;
+		virtual pod::Vector3* expand() const = 0;
+		virtual pod::Vector3 support( const pod::Vector3& ) const = 0;
+		virtual pod::Collider::Manifold intersects( const pod::Collider& ) const;
+
+		pod::Vector3f getPosition() const;
+		pod::Transform<>& getTransform();
+		const pod::Transform<>& getTransform() const;
+		void setTransform( const pod::Transform<>& );
+	};
+}
\ No newline at end of file
diff --git a/engine/inc/uf/utils/math/collision/mesh.h b/engine/inc/uf/utils/math/collision/mesh.h
new file mode 100644
index 00000000..0ebb50b5
--- /dev/null
+++ b/engine/inc/uf/utils/math/collision/mesh.h
@@ -0,0 +1,33 @@
+#pragma once
+
+#include "gjk.h"
+#include <uf/utils/graphic/mesh.h>
+
+namespace uf {
+	class UF_API MeshCollider : public pod::Collider {
+	protected:
+		std::vector<pod::Vector3> m_positions;
+	public:
+		MeshCollider( const pod::Transform<>& = {}, const std::vector<pod::Vector3>& = {} );
+
+	 	std::vector<pod::Vector3>& getPositions();
+	 	const std::vector<pod::Vector3>& getPositions() const;
+		
+		void setPositions( const std::vector<pod::Vector3>& );
+		
+		template<typename T, typename U>
+		void setPositions( const uf::BaseMesh<T, U>& mesh ) {
+			this->m_positions.clear();
+			this->m_positions.reserve( std::max( mesh.vertices.size(), mesh.indices.size() ) );
+			if ( !mesh.indices.empty() ) {
+				for ( auto& index : mesh.indices ) this->m_positions.push_back( mesh.vertices[index].position );
+			} else {
+				for ( auto& vertex : mesh.vertices ) this->m_positions.push_back( vertex.position );
+			}
+		}
+
+		virtual std::string type() const;
+		virtual pod::Vector3* expand() const;
+		virtual pod::Vector3 support( const pod::Vector3& ) const;
+	};
+}
\ No newline at end of file
diff --git a/engine/inc/uf/utils/math/collision/modular.h b/engine/inc/uf/utils/math/collision/modular.h
new file mode 100644
index 00000000..c515716b
--- /dev/null
+++ b/engine/inc/uf/utils/math/collision/modular.h
@@ -0,0 +1,34 @@
+#pragma once
+
+#include "gjk.h"
+#include <functional>
+
+namespace uf {
+	class UF_API ModularCollider : public pod::Collider {
+	public:
+		typedef std::function<pod::Vector3*()> function_expand_t;
+		typedef std::function<pod::Vector3(const pod::Vector3&)> function_support_t;
+	protected:
+		uint m_len;
+		pod::Vector3* m_container;
+
+		bool m_should_free;
+
+		uf::ModularCollider::function_expand_t m_function_expand;
+		uf::ModularCollider::function_support_t m_function_support;
+	public:
+		ModularCollider( uint len = 0, pod::Vector3* = NULL, bool = false, const uf::ModularCollider::function_expand_t& = NULL, const uf::ModularCollider::function_support_t& = NULL );
+		~ModularCollider();
+		
+		void setExpand( const uf::ModularCollider::function_expand_t& = NULL );
+		void setSupport( const uf::ModularCollider::function_support_t& = NULL );
+		
+		pod::Vector3* getContainer();
+		uint getSize() const;
+		void setContainer( pod::Vector3*, uint );
+
+		virtual std::string type() const;
+		virtual pod::Vector3* expand() const;
+		virtual pod::Vector3 support( const pod::Vector3& ) const;
+	};
+}
\ No newline at end of file
diff --git a/engine/inc/uf/utils/math/collision/sphere.h b/engine/inc/uf/utils/math/collision/sphere.h
new file mode 100644
index 00000000..910af35c
--- /dev/null
+++ b/engine/inc/uf/utils/math/collision/sphere.h
@@ -0,0 +1,24 @@
+#pragma once
+
+#include "gjk.h"
+
+namespace uf {
+	class UF_API SphereCollider : public pod::Collider {
+	protected:
+		float m_radius;
+		pod::Vector3 m_origin;
+	public:
+		SphereCollider( float = 1.0f, const pod::Vector3& = pod::Vector3{} );
+
+		float getRadius() const;
+		const pod::Vector3& getOrigin() const;
+		
+		void setRadius( float = 1.0f );
+		void setOrigin( const pod::Vector3& );
+
+		virtual std::string type() const;
+		virtual pod::Vector3* expand() const;
+		virtual pod::Vector3 support( const pod::Vector3& ) const;
+		virtual pod::Collider::Manifold intersects( const uf::SphereCollider& ) const;
+	};
+}
\ No newline at end of file
diff --git a/engine/inc/uf/utils/math/physics.h b/engine/inc/uf/utils/math/physics.h
index 1aac80ec..e1ea1814 100644
--- a/engine/inc/uf/utils/math/physics.h
+++ b/engine/inc/uf/utils/math/physics.h
@@ -21,8 +21,11 @@ namespace pod {
 namespace uf {
 	namespace physics {
 		namespace time {
-			UF_API uf::Timer<> timer;
-			UF_API double current, previous, delta, clamp;
+			extern UF_API uf::Timer<> timer;
+			extern UF_API double current;
+			extern UF_API double previous;
+			extern UF_API double delta;
+			extern UF_API double clamp;
 		}
 		void UF_API tick();
 		template<typename T> pod::Transform<T>& update( pod::Transform<T>& transform, pod::Physics& physics );
diff --git a/engine/src/engine/asset/asset.cpp b/engine/src/engine/asset/asset.cpp
index 4347662c..bc75382a 100644
--- a/engine/src/engine/asset/asset.cpp
+++ b/engine/src/engine/asset/asset.cpp
@@ -214,8 +214,7 @@ std::string uf::Asset::load( const std::string& uri ) {
 		uf::Serializer& json = container.emplace_back();
 		json.readFromFile(filename);
 	} else {
-		uf::iostream << "Failed to load `" + filename + "`: Unimplemented extension: " + extension << "\n"; 
-		return "";
+		uf::iostream << "Failed to parse `" + filename + "`: Unimplemented extension: " + extension << "\n"; 
 	}
 	return filename;
 }
diff --git a/engine/src/engine/object/object.cpp b/engine/src/engine/object/object.cpp
index a8529c7d..4e919fcc 100644
--- a/engine/src/engine/object/object.cpp
+++ b/engine/src/engine/object/object.cpp
@@ -3,6 +3,11 @@
 #include <uf/engine/scene/scene.h>
 #include <uf/utils/time/time.h>
 #include <uf/utils/math/transform.h>
+#include <uf/utils/math/physics.h>
+#include <uf/utils/graphic/graphic.h>
+#include <uf/utils/camera/camera.h>
+#include <uf/utils/graphic/mesh.h>
+#include <uf/ext/gltf/gltf.h>
 
 namespace {
 	uf::Timer<long long> timer(false);
@@ -14,6 +19,7 @@ namespace {
 			if ( filename.substr(0,9) == "/smtsamo/" ) root = "./data/";
 			else if ( extension == "json" ) root = "./data/entities/";
 			else if ( extension == "png" ) root = "./data/textures/";
+			else if ( extension == "glb" ) root = "./data/models/";
 			else if ( extension == "ogg" ) root = "./data/audio/";
 		}
 		return uf::string::sanitize(filename, root);
@@ -23,6 +29,33 @@ namespace {
 UF_OBJECT_REGISTER_CPP(Object)
 void uf::Object::initialize() {	
 	uf::Entity::initialize();
+
+	uf::Serializer& metadata = this->getComponent<uf::Serializer>();
+	if ( metadata["system"]["type"].isNull() || metadata["system"]["defaults"]["asset load"].asBool()  ) {
+		// Default load: GLTF model
+		this->addHook( "asset:Load.%UID%", [&](const std::string& event)->std::string{	
+			uf::Serializer json = event;
+			std::string filename = json["filename"].asString();
+
+			if ( uf::string::extension(filename) != "glb" ) return "false";
+			int8_t LOAD_FLAGS = 0;
+			if ( metadata["model"]["flags"]["GENERATE_NORMALS"].asBool() )
+				LOAD_FLAGS |= ext::gltf::LoadMode::GENERATE_NORMALS; 	// 0x1 << 0;
+			if ( metadata["model"]["flags"]["APPLY_TRANSFORMS"].asBool() )
+				LOAD_FLAGS |= ext::gltf::LoadMode::APPLY_TRANSFORMS; 	// 0x1 << 1;
+			if ( metadata["model"]["flags"]["SEPARATE_MESHES"].asBool() )
+				LOAD_FLAGS |= ext::gltf::LoadMode::SEPARATE_MESHES; 	// 0x1 << 2;
+			if ( metadata["model"]["flags"]["RENDER"].asBool() )
+				LOAD_FLAGS |= ext::gltf::LoadMode::RENDER; 				// 0x1 << 3;
+			if ( metadata["model"]["flags"]["COLLISION"].asBool() )
+				LOAD_FLAGS |= ext::gltf::LoadMode::COLLISION; 			// 0x1 << 4;
+			if ( metadata["model"]["flags"]["AABB"].asBool() )
+				LOAD_FLAGS |= ext::gltf::LoadMode::AABB; 				// 0x1 << 5;
+
+			ext::gltf::load( *this, filename, LOAD_FLAGS );
+			return "true";
+		});
+	}
 }
 void uf::Object::destroy() {
 	uf::Serializer& metadata = this->getComponent<uf::Serializer>();
@@ -41,10 +74,14 @@ void uf::Object::tick() {
 	// listen for metadata file changes
 	uf::Serializer& metadata = this->getComponent<uf::Serializer>();
 	if ( metadata["system"]["hot reload"]["enabled"].asBool() ) {
+	/*
 		std::string filename = "./entities/"+metadata["system"]["source"].asString();
 		std::string root = "./data/" + uf::string::directory(filename);
 		size_t mtime = uf::string::mtime( root + uf::string::filename(filename) );
+	*/
+		size_t mtime = uf::string::mtime( metadata["system"]["source"].asString() );
 		if ( metadata["system"]["hot reload"]["mtime"].asUInt64() < mtime ) {
+			std::cout << metadata["system"]["hot reload"]["mtime"] << ": " << mtime << std::endl;
 			metadata["system"]["hot reload"]["mtime"] = mtime;
 			this->reload();
 			//this->queueHook("metadata:Reload.%UID%");
@@ -71,6 +108,32 @@ void uf::Object::tick() {
 }
 void uf::Object::render() {
 	uf::Entity::render();
+
+	auto& metadata = this->getComponent<uf::Serializer>();
+	if ( metadata["system"]["type"].isNull() || metadata["system"]["defaults"]["render"].asBool() ) {
+		/* Update uniforms */ if ( this->hasComponent<uf::Graphic>() ) {
+			auto& scene = uf::scene::getCurrentScene();
+			auto& graphic = this->getComponent<uf::Graphic>();
+			auto& transform = this->getComponent<pod::Transform<>>();
+			auto& camera = scene.getController()->getComponent<uf::Camera>();		
+			
+			if ( !graphic.initialized ) return;
+
+			auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
+			uniforms.matrices.model = uf::transform::model( transform );
+			for ( std::size_t i = 0; i < 2; ++i ) {
+				uniforms.matrices.view[i] = camera.getView( i );
+				uniforms.matrices.projection[i] = camera.getProjection( i );
+			}
+
+			uniforms.color[0] = 1;
+			uniforms.color[1] = 1;
+			uniforms.color[2] = 1;
+			uniforms.color[3] = 1;
+
+			graphic.material.shaders.front().updateBuffer( uniforms, 0, false );
+		};
+	}
 }
 
 void uf::Object::queueHook( const std::string& name, const std::string& payload, double timeout ) {
@@ -105,11 +168,11 @@ bool uf::Object::load( const std::string& f, bool inheritRoot ) {
 	}
 	std::string filename = grabURI( f, root );
 	if ( !json.readFromFile( filename ) ) {
-		uf::iostream << "Error: failed to open `" + filename + "`" << "\n";
+		uf::iostream << "Error @ " << __FILE__ << ":" << __LINE__ << ": failed to open `" + filename + "`" << "\n";
 		return false;
 	}
 	json["root"] = uf::string::directory(filename);
-	json["source"] = uf::string::filename(filename);
+	json["source"] = filename; // uf::string::filename(filename);
 	json["hot reload"]["mtime"] = uf::string::mtime(filename);
 	return this->load(json);
 }
@@ -118,9 +181,10 @@ bool uf::Object::reload( bool hard ) {
 	uf::Serializer& metadata = this->getComponent<uf::Serializer>();
 	if ( !metadata["system"]["source"].isString() ) return false;
 	uf::Serializer json;
-	std::string filename = grabURI( metadata["system"]["source"].asString(), metadata["system"]["root"].asString() ); // uf::string::sanitize(metadata["system"]["source"].asString(), metadata["system"]["root"].asString());
+	std::string filename = metadata["system"]["source"].asString(); //grabURI( metadata["system"]["source"].asString(), metadata["system"]["root"].asString() ); // uf::string::sanitize(metadata["system"]["source"].asString(), metadata["system"]["root"].asString());
 	if ( !json.readFromFile( filename ) ) {
-		uf::iostream << "Error: failed to open `" + filename + "`" << "\n";
+		uf::iostream << "Error @ " << __FILE__ << ":" << __LINE__ << ": failed to open `" + filename + "`" << "\n";
+		uf::iostream << this << ": " << this->getName() << ": " << this->getUid() << ": " << metadata << "\n";
 		return false;
 	}
 	if ( hard ) return this->load(filename);
@@ -136,11 +200,11 @@ std::size_t uf::Object::loadChild( const std::string& f, bool initialize ) {
 	uf::Serializer json;
 	std::string filename = grabURI( f, metadata["system"]["root"].asString() );
 	if ( !json.readFromFile(filename) ) {
-		uf::iostream << "Error: failed to open `" + filename + "`" << "\n";
+		uf::iostream << "Error @ " << __FILE__ << ":" << __LINE__ << ": failed to open `" + filename + "`" << "\n";
 		return -1;
 	}
 	json["root"] = uf::string::directory(filename);
-	json["source"] = uf::string::filename(filename);
+	json["source"] = metadata["system"]["source"].asString(); //uf::string::filename(filename);
 	json["hot reload"]["mtime"] = uf::string::mtime( filename );
 	return this->loadChild(json, initialize);
 }
@@ -150,7 +214,9 @@ bool uf::Object::load( const uf::Serializer& json ) {
 	{
 		// Set name
 		this->m_name = json["name"].isString() ? json["name"].asString() : json["type"].asString();
-		// Set transform
+	}
+	// Set transform
+	{
 		bool load = json["transform"].isObject();
 		if ( this->hasComponent<pod::Transform<>>() ) load = false;
 		pod::Transform<>& transform = this->getComponent<pod::Transform<>>();
@@ -182,6 +248,25 @@ bool uf::Object::load( const uf::Serializer& json ) {
 			transform = uf::transform::reorient( transform );
 		}
 	}
+	// Set movement
+	{
+		if ( json["physics"].isObject() && !this->hasComponent<pod::Physics>() ) {
+			auto& physics = this->getComponent<pod::Physics>();
+			if ( json["physics"]["linear"]["velocity"].isArray() )
+				for ( uint j = 0; j < 3; ++j )
+					physics.linear.velocity[j] = json["physics"]["linear"]["velocity"][j].asFloat();
+			if ( json["physics"]["linear"]["acceleration"].isArray() )
+				for ( uint j = 0; j < 3; ++j )
+					physics.linear.acceleration[j] = json["physics"]["linear"]["acceleration"][j].asFloat();
+			
+			if ( json["physics"]["rotational"]["velocity"].isArray() )
+				for ( uint j = 0; j < 4; ++j )
+					physics.rotational.velocity[j] = json["physics"]["rotational"]["velocity"][j].asFloat();
+			if ( json["physics"]["rotational"]["acceleration"].isArray() )
+				for ( uint j = 0; j < 4; ++j )
+					physics.rotational.acceleration[j] = json["physics"]["rotational"]["acceleration"][j].asFloat();
+		}
+	}
 
 	uf::Scene& scene = this->getRootParent<uf::Scene>();
 	uf::Asset& assetLoader = scene.getComponent<uf::Asset>();
@@ -204,12 +289,6 @@ bool uf::Object::load( const uf::Serializer& json ) {
 			std::string filename = grabURI( target[i].asString(), json["root"].asString() );
 			if ( uf::string::extension(filename) != "ogg" ) continue;
 			if ( (canonical = assetLoader.load( filename )) != "" ) {
-			/*
-				uf::Serializer queue;
-				queue["name"] = "asset:Load.%UID%";
-				queue["payload"]["filename"] = canonical;
-				metadata["system"]["hooks"]["queue"].append(queue);
-			*/
 				uf::Serializer payload;
 				payload["filename"] = canonical;
 				this->queueHook( "asset:Load.%UID%", payload );
@@ -234,12 +313,6 @@ bool uf::Object::load( const uf::Serializer& json ) {
 			std::string filename = grabURI( target[i].asString(), json["root"].asString() );
 			if ( uf::string::extension(filename) != "png" ) continue;
 			if ( (canonical = assetLoader.load( filename )) != "" ) {
-			/*
-				uf::Serializer queue;
-				queue["name"] = "asset:Load.%UID%";
-				queue["payload"]["filename"] = canonical;
-				metadata["system"]["hooks"]["queue"].append(queue);
-			*/
 				uf::Serializer payload;
 				payload["filename"] = canonical;
 				this->queueHook( "asset:Load.%UID%", payload );
@@ -247,7 +320,31 @@ bool uf::Object::load( const uf::Serializer& json ) {
 		}
 	}
 
-	uf::Serializer queue = metadata["system"]["hooks"]["queue"];
+	// gltf (singular)
+	{
+		// find first valid texture in asset list
+		uf::Serializer target;
+		if ( metadata["system"]["assets"].isArray() ) {
+			target = metadata["system"]["assets"];
+		} else if ( json["assets"].isArray() ) {
+			target = json["assets"];
+		} else if ( json["assets"].isObject() && !json["assets"]["models"].isNull()  ) {
+			target = json["assets"]["models"];
+		}
+		for ( uint i = 0; i < target.size(); ++i ) {
+			std::string canonical = "";
+			std::string f = target[i].asString();
+			std::string filename = grabURI( target[i].asString(), json["root"].asString() );
+			if ( uf::string::extension(filename) != "glb" ) continue;
+			if ( (canonical = assetLoader.load( filename )) != "" ) {
+				uf::Serializer payload;
+				payload["filename"] = canonical;
+				this->queueHook( "asset:Load.%UID%", payload );
+			}
+		}
+	}
+
+	uf::Serializer hooks = metadata["system"]["hooks"];
 	// Metadata
 	if ( json["metadata"] != Json::nullValue ) {
 		uf::Serializer& metadata = this->getComponent<uf::Serializer>();
@@ -255,7 +352,7 @@ bool uf::Object::load( const uf::Serializer& json ) {
 			std::string f = json["metadata"].asString();
 			std::string filename = grabURI( json["metadata"].asString(), json["root"].asString() );
 			if ( !metadata.readFromFile(filename) ) {
-				uf::iostream << "Error: failed to open `" + filename + "`" << "\n";
+				uf::iostream << "Error @ " << __FILE__ << ":" << __LINE__ << ": failed to open `" + filename + "`" << "\n";
 				return false;
 			}
 		} else {
@@ -264,7 +361,11 @@ bool uf::Object::load( const uf::Serializer& json ) {
 	}
 	metadata["system"] = json;
 	metadata["system"].removeMember("metadata");
-	metadata["system"]["hooks"]["queue"] = queue;
+	metadata["system"]["hooks"] = hooks;
+	for ( auto it = json["system"].begin(); it != json["system"].end(); ++it ) {
+		if ( metadata["system"][it.key().asString()].isNull() )
+			metadata["system"][it.key().asString()] = json["system"][it.key().asString()];
+	}
 
 	// check for children
 	{
@@ -284,15 +385,39 @@ bool uf::Object::load( const uf::Serializer& json ) {
 			if ( uf::string::extension(filename) != "json" ) continue;
 			if ( (filename = assetLoader.load(filename) ) == "" ) continue;
 			if ( !json.readFromFile(filename) ) {
-				uf::iostream << "Error: failed to open `" + filename + "`" << "\n";
+				uf::iostream << "Error @ " << __FILE__ << ":" << __LINE__ << ": failed to open `" + filename + "`" << "\n";
 				continue;
 			}
 			json["root"] = uf::string::directory(filename);
-			json["source"] = uf::string::filename(filename);
+			json["source"] = filename; // uf::string::filename(filename)
 			json["hot reload"]["mtime"] = uf::string::mtime( filename );
 			if ( this->loadChild(json) == -1 ) continue;
 		}
 	}
+	// Add lights
+	if ( metadata["system"]["lights"].isArray() ) {
+		uf::Serializer target = metadata["system"]["lights"];
+		for ( uint i = 0; i < target.size(); ++i ) {
+			uf::Serializer json = target[i];
+			auto* light = this->findByUid(this->loadChild("/light.json", false));
+			if ( !light ) continue;
+			auto& metadata = light->getComponent<uf::Serializer>();
+			auto& transform = light->getComponent<pod::Transform<>>();
+			if ( json["position"].isArray() )
+				for ( uint j = 0; j < 3; ++j ) transform.position[j] = json["position"][j].asFloat();
+			if ( json["orientation"].isArray() )
+				for ( uint j = 0; j < 4; ++j ) transform.orientation[j] = json["orientation"][j].asFloat();
+
+			if ( !json["color"].isNull() ) metadata["light"]["color"] = json["color"];
+			if ( !json["radius"].isNull() ) metadata["light"]["radius"] = json["radius"];
+			if ( !json["power"].isNull() ) metadata["light"]["power"] = json["power"];
+			if ( !json["shadows"].isNull() ) metadata["light"]["shadows"] = json["shadows"];
+
+			light->initialize();
+
+			// std::cout << json << "\t" << metadata["light"] << std::endl;
+		}
+	}
 
 	return true;
 }
@@ -303,7 +428,7 @@ std::size_t uf::Object::loadChild( const uf::Serializer& json, bool initialize )
 	entity = uf::instantiator::instantiate(type);
 
 	if ( !((uf::Object*) entity)->load(json) ) {
-		uf::iostream << "Error loading `" << json << "!" << "\n";
+		uf::iostream << "Error @ " << __FILE__ << ":" << __LINE__ << " loading `" << json << "!" << "\n";
 		delete entity;
 		return -1;
 	}
diff --git a/engine/src/engine/scene/scene.cpp b/engine/src/engine/scene/scene.cpp
index d1c1b3d8..05812eae 100644
--- a/engine/src/engine/scene/scene.cpp
+++ b/engine/src/engine/scene/scene.cpp
@@ -1,22 +1,174 @@
 #include <uf/engine/scene/scene.h>
 #include <uf/ext/vulkan/vulkan.h>
 #include <uf/utils/string/ext.h>
+#include <uf/utils/camera/camera.h>
+
+#include <uf/ext/vulkan/rendermodes/deferred.h>
+#include <uf/ext/vulkan/rendermodes/rendertarget.h>
+#include <uf/ext/vulkan/rendermodes/stereoscopic_deferred.h>
 
 UF_OBJECT_REGISTER_CPP(Scene)
 void uf::Scene::initialize() {
-//	this->m_graphics = new std::vector<ext::vulkan::Graphic*>();
-//	ext::vulkan::graphics = (std::vector<ext::vulkan::Graphic*>*) this->m_graphics;
 	ext::vulkan::scenes.push_back(this);
 	ext::vulkan::rebuild = true;
 	uf::Object::initialize();
 }
 void uf::Scene::tick() {
-//	ext::vulkan::graphics = (std::vector<ext::vulkan::Graphic*>*) this->m_graphics;
 	uf::Object::tick();
+
+	if ( uf::scene::getCurrentScene().getUid() == this->getUid() ) {
+		uf::Serializer& metadata = this->getComponent<uf::Serializer>();
+		/* Update lights */ if ( metadata["light"]["should"].asBool() ) {
+		//	if ( !ext::vulkan::currentRenderMode || ext::vulkan::currentRenderMode->name != "" ) return;
+
+			auto& scene = uf::scene::getCurrentScene();
+
+			std::vector<ext::vulkan::Graphic*> blitters;
+			auto& renderMode = ext::vulkan::getRenderMode("", true);
+			if ( renderMode.getType() == "Deferred (Stereoscopic)" ) {
+				auto* renderModePointer = (ext::vulkan::StereoscopicDeferredRenderMode*) &renderMode;
+				blitters.push_back(&renderModePointer->blitters.left);
+				blitters.push_back(&renderModePointer->blitters.right);
+			} else if ( renderMode.getType() == "Deferred" ) {
+				auto* renderModePointer = (ext::vulkan::DeferredRenderMode*) &renderMode;
+				blitters.push_back(&renderModePointer->blitter);
+			}
+			auto& controller = *scene.getController();
+			auto& camera = controller.getComponent<uf::Camera>();
+		
+		//	auto& uniforms = blitter.uniforms;
+			struct UniformDescriptor {
+				struct Matrices {
+					alignas(16) pod::Matrix4f view[2];
+					alignas(16) pod::Matrix4f projection[2];
+				} matrices;
+				alignas(16) pod::Vector4f ambient;
+				struct Light {
+					alignas(16) pod::Vector4f position;
+					alignas(16) pod::Vector4f color;
+					alignas(8) pod::Vector2i type;
+					alignas(16) pod::Matrix4f view;
+					alignas(16) pod::Matrix4f projection;
+				} lights;
+			};
+			
+			struct SpecializationConstant {
+				int32_t maxLights = 16;
+			} specializationConstants;
+
+			for ( size_t _ = 0; _ < blitters.size(); ++_ ) {
+				auto& blitter = *blitters[_];
+				
+				uint8_t* buffer;
+				size_t len;
+				auto* shader = &blitter.material.shaders.front();
+				
+				for ( auto& _ : blitter.material.shaders ) {
+					if ( _.uniforms.empty() ) continue;
+					auto& userdata = _.uniforms.front();
+					buffer = (uint8_t*) (void*) userdata;
+					len = userdata.data().len;
+					shader = &_;
+					specializationConstants = _.specializationConstants.get<SpecializationConstant>();
+				}
+
+				if ( !buffer ) continue;
+
+				UniformDescriptor* uniforms = (UniformDescriptor*) buffer;
+				for ( std::size_t i = 0; i < 2; ++i ) {
+					uniforms->matrices.view[i] = camera.getView( i );
+					uniforms->matrices.projection[i] = camera.getProjection( i );
+				}
+				{
+					uniforms->ambient.x = metadata["light"]["ambient"][0].asFloat();
+					uniforms->ambient.y = metadata["light"]["ambient"][1].asFloat();
+					uniforms->ambient.z = metadata["light"]["ambient"][2].asFloat();
+					uniforms->ambient.w = metadata["light"]["kexp"].asFloat();
+				}
+				{
+					std::vector<uf::Entity*> entities;
+					std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
+						if ( !entity || entity->getName() != "Light" ) return;
+						entities.push_back(entity);
+					};
+					for ( uf::Scene* scene : ext::vulkan::scenes ) { if ( !scene ) continue;
+						scene->process(filter);
+					}
+					{
+						const pod::Vector3& position = controller.getComponent<pod::Transform<>>().position;
+						std::sort( entities.begin(), entities.end(), [&]( const uf::Entity* l, const uf::Entity* r ){
+							if ( !l ) return false; if ( !r ) return true;
+							if ( !l->hasComponent<pod::Transform<>>() ) return false; if ( !r->hasComponent<pod::Transform<>>() ) return true;
+							return uf::vector::magnitude( uf::vector::subtract( l->getComponent<pod::Transform<>>().position, position ) ) < uf::vector::magnitude( uf::vector::subtract( r->getComponent<pod::Transform<>>().position, position ) );
+						} );
+					}
+
+					{
+						uf::Serializer& metadata = controller.getComponent<uf::Serializer>();
+						if ( metadata["light"]["should"].asBool() ) entities.push_back(&controller);
+					}
+					UniformDescriptor::Light* lights = (UniformDescriptor::Light*) &buffer[sizeof(UniformDescriptor) - sizeof(UniformDescriptor::Light)];
+					for ( size_t i = 0; i < specializationConstants.maxLights; ++i ) {
+						UniformDescriptor::Light& light = lights[i];
+						light.position = { 0, 0, 0, 0 };
+						light.color = { 0, 0, 0, 0 };
+						light.type = { 0, 0 };
+					}
+
+					blitter.material.textures.clear();
+
+					for ( size_t i = 0; i < specializationConstants.maxLights && i < entities.size(); ++i ) {
+						UniformDescriptor::Light& light = lights[i];
+						uf::Entity* entity = entities[i];
+
+						pod::Transform<>& transform = entity->getComponent<pod::Transform<>>();
+						uf::Serializer& metadata = entity->getComponent<uf::Serializer>();
+						uf::Camera& camera = entity->getComponent<uf::Camera>();
+						
+						light.position.x = transform.position.x;
+						light.position.y = transform.position.y;
+						light.position.z = transform.position.z;
+
+						light.view = camera.getView();
+						light.projection = camera.getProjection();
+
+						if ( entity == &controller ) light.position.y += 2;
+
+						light.position.w = metadata["light"]["power"].asFloat();
+
+						light.color.x = metadata["light"]["color"][0].asFloat();
+						light.color.y = metadata["light"]["color"][1].asFloat();
+						light.color.z = metadata["light"]["color"][2].asFloat();
+
+						light.color.w = metadata["light"]["radius"].asFloat();
+
+						light.type.x = metadata["light"]["type"].asUInt64();
+						light.type.y = metadata["light"]["shadows"]["enabled"].asBool();
+						
+						if ( entity->hasComponent<ext::vulkan::RenderTargetRenderMode>() ) {
+							auto& renderMode = entity->getComponent<ext::vulkan::RenderTargetRenderMode>();
+							auto& renderTarget = renderMode.renderTarget;
+							for ( auto& attachment : renderTarget.attachments ) {
+								if ( !(attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT) ) continue;
+								auto& texture = blitter.material.textures.emplace_back();
+								texture.aliasAttachment(attachment);
+								light.type.y = true;
+								break;
+							}
+						} else {
+							light.type.y = false;
+						}
+					}
+				}
+				blitter.getPipeline().update( blitter );
+				shader->updateBuffer( (void*) buffer, len, 0, false );
+			}
+		}
+	}
 }
 void uf::Scene::render() {
-//	ext::vulkan::graphics = (std::vector<ext::vulkan::Graphic*>*) this->m_graphics;
 	uf::Object::render();
+
 }
 void uf::Scene::destroy() {
 	uf::Object::destroy();
@@ -27,29 +179,45 @@ void uf::Scene::destroy() {
 			ext::vulkan::scenes.erase(it);
 		}
 	}
-/*	
-	ext::vulkan::scenes.erase(
-		std::remove(ext::vulkan::scenes.begin(), ext::vulkan::scenes.end(), this),
-		ext::vulkan::scenes.end()
-	);
-*/
 	ext::vulkan::rebuild = true;
-/*
-	std::vector<ext::vulkan::Graphic*>* graphics = (std::vector<ext::vulkan::Graphic*>*) this->m_graphics;
-	for ( auto* graphic : *graphics ) {
-		graphic->destroy();
-	}
-	delete graphics;
-	ext::vulkan::graphics = NULL;
-*/
 }
 
+
+
+/*
 uf::Entity* uf::Scene::getController() {
 	return this->findByName("Player");
 }
 const uf::Entity* uf::Scene::getController() const {
 	return this->findByName("Player");
 }
+*/
+uf::Entity* uf::Scene::getController() {
+	if ( ext::vulkan::currentRenderMode ) {
+		auto& renderMode = *ext::vulkan::currentRenderMode;
+		std::string name = renderMode.name;
+		auto split = uf::string::split( name, ": " );
+		if ( split.front() == "Render Target" ) {
+			uint64_t uid = std::stoi( split.back() );
+			uf::Entity* ent = this->findByUid( uid );
+			if ( ent ) return ent;
+		}
+	}
+	return this->findByName("Player");
+}
+const uf::Entity* uf::Scene::getController() const {
+	if ( ext::vulkan::currentRenderMode ) {
+		auto& renderMode = *ext::vulkan::currentRenderMode;
+		std::string name = renderMode.name;
+		auto split = uf::string::split( name, ": " );
+		if ( split.front() == "Render Target" ) {
+			uint64_t uid = std::stoi( split.back() );
+			const uf::Entity* ent = this->findByUid( uid );
+			if ( ent ) return ent;
+		}
+	}
+	return this->findByName("Player");
+}
 
 std::vector<uf::Scene*> uf::scene::scenes;
 uf::Scene& uf::scene::loadScene( const std::string& name, const std::string& filename ) {
diff --git a/engine/src/ext/gltf/gltf.cpp b/engine/src/ext/gltf/gltf.cpp
new file mode 100644
index 00000000..3ffce722
--- /dev/null
+++ b/engine/src/ext/gltf/gltf.cpp
@@ -0,0 +1,334 @@
+#define TINYGLTF_IMPLEMENTATION
+#define STB_IMAGE_WRITE_IMPLEMENTATION
+
+#include <gltf/tiny_gltf.h>
+
+#include <uf/ext/gltf/gltf.h>
+#include <uf/utils/string/ext.h>
+#include <uf/utils/math/transform.h>
+#include <uf/utils/graphic/mesh.h>
+#include <uf/utils/graphic/graphic.h>
+#include <uf/utils/math/collision.h>
+
+namespace {
+
+VkSamplerAddressMode getVkWrapMode(int32_t wrapMode) {
+	switch (wrapMode) {
+		case 10497: return VK_SAMPLER_ADDRESS_MODE_REPEAT;
+		case 33071: return VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
+		case 33648: return VK_SAMPLER_ADDRESS_MODE_MIRRORED_REPEAT;
+		default: return VK_SAMPLER_ADDRESS_MODE_REPEAT;
+	}
+}
+
+VkFilter getVkFilterMode(int32_t filterMode) {
+	switch (filterMode) {
+		case 9728: return VK_FILTER_NEAREST;
+		case 9729: return VK_FILTER_LINEAR;
+		case 9984: return VK_FILTER_NEAREST;
+		case 9985: return VK_FILTER_NEAREST;
+		case 9986: return VK_FILTER_LINEAR;
+		case 9987: return VK_FILTER_LINEAR;
+		default: return VK_FILTER_LINEAR;
+	}
+}
+
+void loadNode( uf::Object& entity, const tinygltf::Model& model, const tinygltf::Node& node, uint8_t mode ) {
+	auto& transform = entity.getComponent<pod::Transform<>>();
+
+	if ( node.translation.size() == 3 ) {
+		transform.position.x = node.translation[0];
+		transform.position.y = node.translation[1];
+		transform.position.z = node.translation[2];
+	}
+	if ( node.rotation.size() == 4 ) {
+		transform.orientation.x = node.rotation[0];
+		transform.orientation.y = node.rotation[1];
+		transform.orientation.z = node.rotation[2];
+		transform.orientation.w = node.rotation[3];
+	}
+	if ( node.scale.size() == 3 ) {
+		transform.scale.x = node.scale[0];
+		transform.scale.y = node.scale[1];
+		transform.scale.z = node.scale[2];
+	}
+// 	if ( node.matrix.size() == 16 ) {}
+
+	auto fillMesh = [&]( uf::BaseMesh<pod::Vertex_3F2F3F, uint32_t>& mesh, const tinygltf::Primitive& primitive, uf::Collider& collider ) {
+		size_t verticesStart = mesh.vertices.size();
+		size_t indicesStart = mesh.indices.size();
+
+		size_t vertices = 0;
+		struct Attribute {
+			std::string name = "";
+			size_t components = 1;
+			std::vector<float> buffer;
+		};
+		std::unordered_map<std::string, Attribute> attributes = {
+			{"POSITION", {}},
+			{"TEXCOORD_0", {}},
+			{"NORMAL", {}},
+		};
+
+		for ( auto& kv : attributes ) {
+			auto& attribute = kv.second;
+			attribute.name = kv.first;
+			auto it = primitive.attributes.find(attribute.name);
+			if ( it == primitive.attributes.end() ) continue;
+
+			auto& accessor = model.accessors[it->second];
+			auto& view = model.bufferViews[accessor.bufferView];
+			auto* buffer = reinterpret_cast<const float*>(&(model.buffers[view.buffer].data[accessor.byteOffset + view.byteOffset]));
+			
+			if ( attribute.name == "POSITION" ) {
+				vertices = accessor.count;
+				pod::Vector3f minCorner = { accessor.minValues[0], accessor.minValues[1], accessor.minValues[2] };
+				pod::Vector3f maxCorner = { accessor.maxValues[0], accessor.maxValues[1], accessor.maxValues[2] };
+
+				pod::Vector3f origin = (maxCorner + minCorner) * 0.5f;
+				pod::Vector3f size = (maxCorner - minCorner) * 0.5f;
+
+				if ( (mode & ext::gltf::LoadMode::COLLISION) && (mode & ext::gltf::LoadMode::AABB) ) {
+					auto* box = new uf::BoundingBox( origin, size );
+					collider.add(box);
+				}
+			}
+
+			attribute.components = accessor.ByteStride(view) / sizeof(float);
+			attribute.buffer.reserve( accessor.count * attribute.components );
+			attribute.buffer.insert( attribute.buffer.end(), &buffer[0], &buffer[accessor.count * attribute.components] );
+		}
+
+		mesh.vertices.reserve( vertices + verticesStart );
+
+		for ( size_t i = 0; i < vertices; ++i ) {
+			auto& vertex = mesh.vertices.emplace_back();
+
+			#define ITERATE_ATTRIBUTE( name, member )\
+				if ( !attributes[name].buffer.empty() ) { \
+					for ( size_t j = 0; j < attributes[name].components; ++j )\
+						vertex.member[j] = attributes[name].buffer[i * attributes[name].components + j];\
+				}
+
+			ITERATE_ATTRIBUTE("POSITION", position);
+			ITERATE_ATTRIBUTE("TEXCOORD_0", uv);
+			ITERATE_ATTRIBUTE("NORMAL", normal);
+
+			#undef ITERATE_ATTRIBUTE
+		}
+
+
+		if ( primitive.indices > -1 ) {
+			auto& accessor = model.accessors[primitive.indices];
+			auto& view = model.bufferViews[accessor.bufferView];
+			auto& buffer = model.buffers[view.buffer];
+
+			mesh.indices.reserve( accessor.count + indicesStart );
+
+			const void* pointer = &(buffer.data[accessor.byteOffset + view.byteOffset]);
+			switch (accessor.componentType) {
+				case TINYGLTF_PARAMETER_TYPE_UNSIGNED_INT: {
+					auto* buf = static_cast<const uint32_t*>( pointer );
+					for (size_t index = 0; index < accessor.count; index++) mesh.indices.push_back(buf[index] + verticesStart );
+					break;
+				}
+				case TINYGLTF_PARAMETER_TYPE_UNSIGNED_SHORT: {
+					auto* buf = static_cast<const uint16_t*>( pointer );
+					for (size_t index = 0; index < accessor.count; index++) mesh.indices.push_back(buf[index] + verticesStart );
+					break;
+				}
+				case TINYGLTF_PARAMETER_TYPE_UNSIGNED_BYTE: {
+					auto* buf = static_cast<const uint8_t*>( pointer );
+					for (size_t index = 0; index < accessor.count; index++) mesh.indices.push_back(buf[index] + verticesStart );
+					break;
+				}
+			}
+
+			if ( mode & ext::gltf::LoadMode::GENERATE_NORMALS ) {
+				for ( size_t i = 0; i < mesh.indices.size(); i+=3 ) {
+					auto& A = mesh.vertices[mesh.indices[i+0]];
+					auto& B = mesh.vertices[mesh.indices[i+1]];
+					auto& C = mesh.vertices[mesh.indices[i+2]];
+
+					auto& a = A.position;
+					auto& b = B.position;
+					auto& c = C.position;
+
+					pod::Vector3f normal = uf::vector::normalize( uf::vector::cross( b - a, c - a ) );
+					
+					A.normal = normal;
+					B.normal = normal;
+					C.normal = normal;
+				}
+			}
+		} else {
+			// recalc normals
+			if ( mode & ext::gltf::LoadMode::GENERATE_NORMALS ) {
+				// bool invert = false;
+				for ( size_t i = 0; i < mesh.vertices.size(); i+=3 ) {
+				//	auto& b = mesh.vertices[i+(invert ? 2 : 1)].position;
+				//	auto& c = mesh.vertices[i+(invert ? 1 : 2)].position;
+					auto& a = mesh.vertices[i+0].position;
+					auto& b = mesh.vertices[i+1].position;
+					auto& c = mesh.vertices[i+2].position;
+
+					pod::Vector3f normal = uf::vector::normalize( uf::vector::cross( b - a, c - a ) );
+					mesh.vertices[i+0].normal = normal;
+					mesh.vertices[i+1].normal = normal;
+					mesh.vertices[i+2].normal = normal;
+				}
+			}
+		}
+		if ( mode & ext::gltf::LoadMode::APPLY_TRANSFORMS ) {
+			pod::Matrix4f model = uf::transform::model( transform );
+			for ( auto& vertex : mesh.vertices ) {
+				vertex.position = uf::matrix::multiply<float>( model, vertex.position );
+			}
+		}
+	};
+
+	if ( node.mesh > -1 ) {
+		auto& m = model.meshes[node.mesh];
+		std::vector<ext::vulkan::Sampler> samplers;
+		std::vector<uf::Image> images;
+	/*
+		std::vector<uf::Object> lights;
+		for ( auto& l : model.lights ) {
+			auto& light = lights.emplace_back();
+			auto& metadata = light.getComponent<uf::Serializer>();
+			metadata["light"]["color"][0] = l.color[0];
+			metadata["light"]["color"][1] = l.color[1];
+			metadata["light"]["color"][2] = l.color[2];
+			
+			metadata["light"]["radius"] = l.range;
+			metadata["light"]["power"] = l.intensity;
+
+			std::cout << metadata << std::endl;
+		}
+	*/
+		for ( auto& s : model.samplers ) {
+			auto& sampler = samplers.emplace_back();
+			sampler.descriptor.filter.min = getVkFilterMode( s.minFilter );
+			sampler.descriptor.filter.mag = getVkFilterMode( s.magFilter );
+			sampler.descriptor.addressMode.u = getVkWrapMode( s.wrapS );
+			sampler.descriptor.addressMode.v = getVkWrapMode( s.wrapT );
+			sampler.descriptor.addressMode.w = sampler.descriptor.addressMode.v;
+		}
+		for ( auto& t : model.textures ) {
+			auto& im = model.images[t.source];
+			uf::Image& image = images.emplace_back();
+		//	std::cout << "Loading image: " << im.width << ", " << im.height << std::endl;
+			image.loadFromBuffer( &im.image[0], {im.width, im.height}, 8, im.component, true );
+		}
+	//	if ( model.textures.size() > 1 && m.primitives.size() == model.textures.size() ) {
+		if ( mode & ext::gltf::LoadMode::SEPARATE_MESHES ) {
+			auto sampler = samplers.begin();
+			auto image = images.begin();
+			for ( auto& primitive : m.primitives ) {
+				uf::Object* child = new uf::Object;
+				
+				uf::BaseMesh<pod::Vertex_3F2F3F, uint32_t> mesh;
+				auto& cTransform = child->getComponent<pod::Transform<>>();
+				cTransform = transform;
+
+				auto& collider = child->getComponent<uf::Collider>();
+				fillMesh( mesh, primitive, collider );
+
+				if ( (mode & ext::gltf::LoadMode::COLLISION) && !(mode & ext::gltf::LoadMode::AABB) ) {
+					auto* box = new uf::MeshCollider( cTransform );
+					box->setPositions( mesh );
+					collider.add(box);
+				}
+				if ( mode & ext::gltf::LoadMode::RENDER ) {
+					auto& graphic = child->getComponent<uf::Graphic>();
+				//	graphic.descriptor.cullMode = VK_CULL_MODE_NONE;
+					graphic.initialize();
+					graphic.initializeGeometry( mesh );
+
+					graphic.material.attachShader("./data/shaders/base.stereo.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
+					graphic.material.attachShader("./data/shaders/base.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
+					
+					if ( image != images.end() ) graphic.material.textures.emplace_back().loadFromImage( *(image++) );
+					if ( sampler != samplers.end() ) graphic.material.samplers.push_back( *(sampler++) );
+				}
+				for ( auto* collider : collider.getContainer() ) collider->getTransform().reference = &cTransform;
+
+				entity.addChild( *child );
+				child->initialize();
+				
+				if ( mode & ext::gltf::LoadMode::APPLY_TRANSFORMS ) cTransform = {};
+			}
+		} else {		
+			uf::BaseMesh<pod::Vertex_3F2F3F, uint32_t> mesh;
+			auto& collider = entity.getComponent<uf::Collider>();
+
+			for ( auto& primitive : m.primitives ) fillMesh( mesh, primitive, collider );
+		
+			if ( (mode & ext::gltf::LoadMode::COLLISION) && !(mode & ext::gltf::LoadMode::AABB) ) {
+				auto* c = new uf::MeshCollider( transform );
+				c->setPositions( mesh );
+				collider.add(c);
+			}
+
+			for ( auto* collider : collider.getContainer() ) collider->getTransform().reference = &transform;
+
+			if ( mode & ext::gltf::LoadMode::RENDER ) {
+				auto& graphic = entity.getComponent<uf::Graphic>();
+
+				graphic.initialize();
+				graphic.initializeGeometry( mesh );
+
+				graphic.material.attachShader("./data/shaders/base.stereo.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
+				graphic.material.attachShader("./data/shaders/base.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
+
+				for ( auto& image : images ) graphic.material.textures.emplace_back().loadFromImage( image );
+				for ( auto& sampler : samplers ) graphic.material.samplers.push_back(sampler);
+			}
+			if ( mode & ext::gltf::LoadMode::APPLY_TRANSFORMS ) transform = {};
+		}
+	}
+
+	for ( auto i : node.children ) {
+		uf::Object* child = new uf::Object;
+		entity.addChild( *child );
+		loadNode( *child, model, model.nodes[i], mode );
+		child->initialize();
+	}
+}
+
+}
+
+bool ext::gltf::load( uf::Object& entity, const std::string& filename, uint8_t mode ) {
+	tinygltf::Model model;
+	tinygltf::TinyGLTF loader;
+
+	std::string warn, err;
+	std::string extension = uf::string::extension( filename );
+	bool ret;
+	if ( extension == "glb" ) 
+		ret = loader.LoadBinaryFromFile(&model, &err, &warn, filename); // for binary glTF(.glb)
+	else
+		ret = loader.LoadASCIIFromFile(&model, &err, &warn, filename);
+
+	if ( !warn.empty() ) std::cout << "glTF warning: " << warn << std::endl;
+	if ( !err.empty() ) std::cout << "glTF error: " << err << std::endl;
+	if ( !ret ) { std::cout << "glTF error: failed to parse file: " << filename << std::endl;
+		return false;
+	}
+
+	const auto& scene = model.scenes[model.defaultScene > -1 ? model.defaultScene : 0];
+	for ( auto i : scene.nodes ) {
+		loadNode( entity, model, model.nodes[i], mode );
+	}
+
+	// parent transform
+	auto& transform = entity.getComponent<pod::Transform<>>();
+	std::function<void(uf::Entity*)> filter = [&]( uf::Entity* child ) {
+		if ( child == &entity ) return;
+		if ( !child->hasComponent<pod::Transform<>>() ) return;
+		child->getComponent<pod::Transform<>>().reference = &transform;
+	};
+	entity.process(filter);
+
+	return true;
+}
\ No newline at end of file
diff --git a/engine/src/ext/openvr/openvr.cpp b/engine/src/ext/openvr/openvr.cpp
index dde862ee..d7875f5d 100644
--- a/engine/src/ext/openvr/openvr.cpp
+++ b/engine/src/ext/openvr/openvr.cpp
@@ -14,6 +14,7 @@ float ext::openvr::width = 0;
 float ext::openvr::height = 0;
 bool ext::openvr::enabled = false;
 bool ext::openvr::swapEyes = false;
+uint8_t ext::openvr::dominantEye = 0;
 
 #define VR_CHECK_INPUT_RESULT(f)\
 	if ( f != vr::VRInputError_None ) {\
@@ -556,7 +557,7 @@ pod::Matrix4t<> ext::openvr::hmdProjectionMatrix( vr::Hmd_Eye eye, float zNear,
 		frustum.bottom = abs( frustum.bottom );
 	} else {
 	}
-		std::cout << frustum.left << "\t" << frustum.right << "\t" << frustum.top << "\t" << frustum.bottom << std::endl;
+	//	std::cout << frustum.left << "\t" << frustum.right << "\t" << frustum.top << "\t" << frustum.bottom << std::endl;
 
 	/*
 		float fov = this->m_settings.perspective.fov * (3.14159265358f / 180.0f);
diff --git a/engine/src/ext/vulkan/device.cpp b/engine/src/ext/vulkan/device.cpp
index 80ff3da5..d800bdb5 100644
--- a/engine/src/ext/vulkan/device.cpp
+++ b/engine/src/ext/vulkan/device.cpp
@@ -8,6 +8,8 @@
 #include <set>
 #include <map>
 
+#include <uf/utils/serialize/serializer.h>
+
 namespace {
 	void VRExtensions( std::vector<std::string>& requested ) {
 		if ( !vr::VRCompositor() ) return;
@@ -18,34 +20,142 @@ namespace {
 		vr::VRCompositor()->GetVulkanInstanceExtensionsRequired( pExtensionStr, nBufferSize );
 		std::vector<std::string> extensions = uf::string::split( pExtensionStr, " " );
 		requested.insert( requested.end(), extensions.begin(), extensions.end() );
-	/*
-		// Allocate enough ExtensionProperties to support all extensions being enabled
-		uint32_t extensionsCount = 0;
-		uint32_t enabledExtensionsCount = 0;
-		
-		VK_CHECK_RESULT(vkEnumerateInstanceExtensionProperties( NULL, &extensionsCount, NULL ));
-		std::vector<VkExtensionProperties> extensionProperties(extensionsCount);
-		VK_CHECK_RESULT( vkEnumerateInstanceExtensionProperties( NULL, &extensionsCount, &extensionProperties[0] ) );
-		for ( size_t i = 0; i < extensions.size(); ++i ) {
-			bool found = false;
-			uint32_t index = 0;
-			for ( index = 0; index < extensionsCount; index++ ) {
-				if ( strcmp( extensions[i].c_str(), extensionProperties[index].extensionName ) == 0 ) {
-					for ( auto alreadyAdded : supportedExtensions ) {
-						if ( strcmp( extensions[i].c_str(), alreadyAdded ) == 0 ) {
-							found = true;
-							break;
-						}
-					}
-					if ( found ) break;
-					found = true;
-					supportedExtensions.push_back(extensionProperties[index].extensionName);
-					break;
-				}
-			}
-			if ( !found ) std::cout << "Vulkan missing requested extension " << extensions[index] << std::endl;
+	}
+	void enableRequestedDeviceFeatures( ext::vulkan::Device& device ) {
+		uf::Serializer json;
+
+	#define CHECK_FEATURE( NAME )\
+		if ( feature == #NAME ) {\
+			if ( device.features.NAME == VK_TRUE ) {\
+				device.enabledFeatures.NAME = true;\
+				if ( ext::vulkan::validation ) std::cout << "Enabled feature: " << feature << std::endl;\
+			} else if ( ext::vulkan::validation ) std::cout << "Failed to enable feature: " << feature << std::endl;\
 		}
-	*/
+
+		for ( auto& feature : ext::vulkan::requestedDeviceFeatures ) {
+			CHECK_FEATURE(robustBufferAccess);
+			CHECK_FEATURE(fullDrawIndexUint32);
+			CHECK_FEATURE(imageCubeArray);
+			CHECK_FEATURE(independentBlend);
+			CHECK_FEATURE(geometryShader);
+			CHECK_FEATURE(tessellationShader);
+			CHECK_FEATURE(sampleRateShading);
+			CHECK_FEATURE(dualSrcBlend);
+			CHECK_FEATURE(logicOp);
+			CHECK_FEATURE(multiDrawIndirect);
+			CHECK_FEATURE(drawIndirectFirstInstance);
+			CHECK_FEATURE(depthClamp);
+			CHECK_FEATURE(depthBiasClamp);
+			CHECK_FEATURE(fillModeNonSolid);
+			CHECK_FEATURE(depthBounds);
+			CHECK_FEATURE(wideLines);
+			CHECK_FEATURE(largePoints);
+			CHECK_FEATURE(alphaToOne);
+			CHECK_FEATURE(multiViewport);
+			CHECK_FEATURE(samplerAnisotropy);
+			CHECK_FEATURE(textureCompressionETC2);
+			CHECK_FEATURE(textureCompressionASTC_LDR);
+			CHECK_FEATURE(textureCompressionBC);
+			CHECK_FEATURE(occlusionQueryPrecise);
+			CHECK_FEATURE(pipelineStatisticsQuery);
+			CHECK_FEATURE(vertexPipelineStoresAndAtomics);
+			CHECK_FEATURE(fragmentStoresAndAtomics);
+			CHECK_FEATURE(shaderTessellationAndGeometryPointSize);
+			CHECK_FEATURE(shaderImageGatherExtended);
+			CHECK_FEATURE(shaderStorageImageExtendedFormats);
+			CHECK_FEATURE(shaderStorageImageMultisample);
+			CHECK_FEATURE(shaderStorageImageReadWithoutFormat);
+			CHECK_FEATURE(shaderStorageImageWriteWithoutFormat);
+			CHECK_FEATURE(shaderUniformBufferArrayDynamicIndexing);
+			CHECK_FEATURE(shaderSampledImageArrayDynamicIndexing);
+			CHECK_FEATURE(shaderStorageBufferArrayDynamicIndexing);
+			CHECK_FEATURE(shaderStorageImageArrayDynamicIndexing);
+			CHECK_FEATURE(shaderClipDistance);
+			CHECK_FEATURE(shaderCullDistance);
+			CHECK_FEATURE(shaderFloat64);
+			CHECK_FEATURE(shaderInt64);
+			CHECK_FEATURE(shaderInt16);
+			CHECK_FEATURE(shaderResourceResidency);
+			CHECK_FEATURE(shaderResourceMinLod);
+			CHECK_FEATURE(sparseBinding);
+			CHECK_FEATURE(sparseResidencyBuffer);
+			CHECK_FEATURE(sparseResidencyImage2D);
+			CHECK_FEATURE(sparseResidencyImage3D);
+			CHECK_FEATURE(sparseResidency2Samples);
+			CHECK_FEATURE(sparseResidency4Samples);
+			CHECK_FEATURE(sparseResidency8Samples);
+			CHECK_FEATURE(sparseResidency16Samples);
+			CHECK_FEATURE(sparseResidencyAliased);
+			CHECK_FEATURE(variableMultisampleRate);
+			CHECK_FEATURE(inheritedQueries);
+		}
+	#undef CHECK_FEATURE
+	}
+	uf::Serializer retrieveDeviceFeatures( ext::vulkan::Device& device ) {
+		uf::Serializer json;
+
+	#define CHECK_FEATURE( NAME )\
+		json[#NAME]["supported"] = device.features.NAME;\
+		json[#NAME]["enabled"] = device.enabledFeatures.NAME;
+
+		CHECK_FEATURE(robustBufferAccess);
+		CHECK_FEATURE(fullDrawIndexUint32);
+		CHECK_FEATURE(imageCubeArray);
+		CHECK_FEATURE(independentBlend);
+		CHECK_FEATURE(geometryShader);
+		CHECK_FEATURE(tessellationShader);
+		CHECK_FEATURE(sampleRateShading);
+		CHECK_FEATURE(dualSrcBlend);
+		CHECK_FEATURE(logicOp);
+		CHECK_FEATURE(multiDrawIndirect);
+		CHECK_FEATURE(drawIndirectFirstInstance);
+		CHECK_FEATURE(depthClamp);
+		CHECK_FEATURE(depthBiasClamp);
+		CHECK_FEATURE(fillModeNonSolid);
+		CHECK_FEATURE(depthBounds);
+		CHECK_FEATURE(wideLines);
+		CHECK_FEATURE(largePoints);
+		CHECK_FEATURE(alphaToOne);
+		CHECK_FEATURE(multiViewport);
+		CHECK_FEATURE(samplerAnisotropy);
+		CHECK_FEATURE(textureCompressionETC2);
+		CHECK_FEATURE(textureCompressionASTC_LDR);
+		CHECK_FEATURE(textureCompressionBC);
+		CHECK_FEATURE(occlusionQueryPrecise);
+		CHECK_FEATURE(pipelineStatisticsQuery);
+		CHECK_FEATURE(vertexPipelineStoresAndAtomics);
+		CHECK_FEATURE(fragmentStoresAndAtomics);
+		CHECK_FEATURE(shaderTessellationAndGeometryPointSize);
+		CHECK_FEATURE(shaderImageGatherExtended);
+		CHECK_FEATURE(shaderStorageImageExtendedFormats);
+		CHECK_FEATURE(shaderStorageImageMultisample);
+		CHECK_FEATURE(shaderStorageImageReadWithoutFormat);
+		CHECK_FEATURE(shaderStorageImageWriteWithoutFormat);
+		CHECK_FEATURE(shaderUniformBufferArrayDynamicIndexing);
+		CHECK_FEATURE(shaderSampledImageArrayDynamicIndexing);
+		CHECK_FEATURE(shaderStorageBufferArrayDynamicIndexing);
+		CHECK_FEATURE(shaderStorageImageArrayDynamicIndexing);
+		CHECK_FEATURE(shaderClipDistance);
+		CHECK_FEATURE(shaderCullDistance);
+		CHECK_FEATURE(shaderFloat64);
+		CHECK_FEATURE(shaderInt64);
+		CHECK_FEATURE(shaderInt16);
+		CHECK_FEATURE(shaderResourceResidency);
+		CHECK_FEATURE(shaderResourceMinLod);
+		CHECK_FEATURE(sparseBinding);
+		CHECK_FEATURE(sparseResidencyBuffer);
+		CHECK_FEATURE(sparseResidencyImage2D);
+		CHECK_FEATURE(sparseResidencyImage3D);
+		CHECK_FEATURE(sparseResidency2Samples);
+		CHECK_FEATURE(sparseResidency4Samples);
+		CHECK_FEATURE(sparseResidency8Samples);
+		CHECK_FEATURE(sparseResidency16Samples);
+		CHECK_FEATURE(sparseResidencyAliased);
+		CHECK_FEATURE(variableMultisampleRate);
+		CHECK_FEATURE(inheritedQueries);
+	#undef CHECK_FEATURE
+
+		return json;
 	}
 }
 
@@ -512,6 +622,8 @@ void ext::vulkan::Device::initialize() {
 			deviceExtensions.push_back(VK_KHR_SWAPCHAIN_EXTENSION_NAME);
 		}
 
+		enableRequestedDeviceFeatures( *this );
+
 		VkDeviceCreateInfo deviceCreateInfo = {};
 		deviceCreateInfo.sType = VK_STRUCTURE_TYPE_DEVICE_CREATE_INFO;
 		deviceCreateInfo.queueCreateInfoCount = static_cast<uint32_t>(queueCreateInfos.size());;
@@ -525,6 +637,9 @@ void ext::vulkan::Device::initialize() {
 
 		if ( vkCreateDevice( this->physicalDevice, &deviceCreateInfo, nullptr, &this->logicalDevice) != VK_SUCCESS )
 			throw std::runtime_error("failed to create logical device!"); 
+
+		if ( ext::vulkan::validation )
+			std::cout << retrieveDeviceFeatures( *this ) << std::endl;
 	}
 	// Create command pool
 	{
diff --git a/engine/src/ext/vulkan/graphic.cpp b/engine/src/ext/vulkan/graphic.cpp
index 08c61ea2..ce008eaa 100644
--- a/engine/src/ext/vulkan/graphic.cpp
+++ b/engine/src/ext/vulkan/graphic.cpp
@@ -58,24 +58,23 @@ void ext::vulkan::Shader::initialize( ext::vulkan::Device& device, const std::st
 		spirv_cross::Compiler comp( (uint32_t*) &spirv[0], spirv.size() / 4 );
 		spirv_cross::ShaderResources res = comp.get_shader_resources();
 
-		auto parseResource = [&]( const spirv_cross::Resource& resource, VkDescriptorType type ) {
-			// comp.get_decoration(resource.id, spv::DecorationDescriptorSet);
-			
-			switch ( type ) {
-				case VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT: {
-				} break;
+		auto parseResource = [&]( const spirv_cross::Resource& resource, VkDescriptorType descriptorType ) {			
+			switch ( descriptorType ) {
 				case VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER: {
-					const auto& type = comp.get_type(resource.base_type_id);
-    				size_t size = comp.get_declared_struct_size(type);
+					const auto& base_type = comp.get_type(resource.base_type_id);
     				auto& uniform = uniforms.emplace_back();
-    				uniform.create( size );
+    				uniform.create( comp.get_declared_struct_size(base_type) );
 				} break;
 			}
-			descriptorSetLayoutBindings.push_back(ext::vulkan::initializers::descriptorSetLayoutBinding( type, stage, comp.get_decoration(resource.id, spv::DecorationBinding) ) );
-			
+
+			const auto& type = comp.get_type(resource.type_id);
+			size_t size = 1;
+			if ( !type.array.empty() ) size = type.array[0];
+
+			descriptorSetLayoutBindings.push_back( ext::vulkan::initializers::descriptorSetLayoutBinding( descriptorType, stage, comp.get_decoration(resource.id, spv::DecorationBinding), size ) );
 		};
+		//	std::cout << "Found resource: "#type " with binding: " << comp.get_decoration(resource.id, spv::DecorationBinding) << std::endl;\
 		
-		//	std::cout << "Found resource: "#type " with binding: " << comp.get_decoration(resource.id, spv::DecorationBinding) << std::endl;
 		#define LOOP_RESOURCES( key, type ) for ( const auto& resource : res.key ) {\
 			parseResource( resource, type );\
 		}
@@ -86,8 +85,7 @@ void ext::vulkan::Shader::initialize( ext::vulkan::Device& device, const std::st
 		LOOP_RESOURCES( uniform_buffers, VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER );
 		LOOP_RESOURCES( subpass_inputs, VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT );
 		LOOP_RESOURCES( storage_buffers, VK_DESCRIPTOR_TYPE_STORAGE_BUFFER );
-	#undef LOOP_RESOURCES
-		
+		#undef LOOP_RESOURCES
 		
 		for ( const auto& resource : res.push_constant_buffers ) {
 			auto& pushConstant = pushConstants.emplace_back();
@@ -196,6 +194,7 @@ void ext::vulkan::Pipeline::initialize( Graphic& graphic ) {
 	this->device = graphic.device;
 	Device& device = *graphic.device;
 
+	// std::cout << &graphic << ": Shaders: " << graphic.material.shaders.size() << " Textures: " << graphic.material.textures.size() << std::endl;
 	assert( graphic.material.shaders.size() > 0 );
 
 	RenderMode& renderMode = ext::vulkan::getRenderMode(graphic.descriptor.renderMode, true);
@@ -274,6 +273,7 @@ void ext::vulkan::Pipeline::initialize( Graphic& graphic ) {
 
 		std::vector<VkPipelineColorBlendAttachmentState> blendAttachmentStates;
 		auto& subpass = renderTarget.passes[graphic.descriptor.subpass];
+	/*
 		for ( auto& color : subpass.colors ) {
 			VkPipelineColorBlendAttachmentState blendAttachmentState = ext::vulkan::initializers::pipelineColorBlendAttachmentState(
 				0xf,
@@ -285,16 +285,19 @@ void ext::vulkan::Pipeline::initialize( Graphic& graphic ) {
 			blendAttachmentState.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE;
 			blendAttachmentState.dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO;
 			blendAttachmentState.alphaBlendOp = VK_BLEND_OP_ADD;
-		/*
-			if ( !blendAttachmentStates.empty() ) {
-				VkPipelineColorBlendAttachmentState blendAttachmentState = ext::vulkan::initializers::pipelineColorBlendAttachmentState(
-					0xf,
-					VK_FALSE
-				);
-			}
-		*/
 			blendAttachmentStates.push_back(blendAttachmentState);
 		}
+	*/
+		for ( auto& color : subpass.colors ) {
+			blendAttachmentStates.push_back(renderTarget.attachments[color.attachment].blendState);
+		}
+		// require blending if independentBlend is not an enabled feature
+		if ( !device.enabledFeatures.independentBlend ) {
+			for ( size_t i = 1; i < blendAttachmentStates.size(); ++i ) {
+				blendAttachmentStates[i] = blendAttachmentStates[0];
+			}
+		}
+
 		VkPipelineColorBlendStateCreateInfo colorBlendState = ext::vulkan::initializers::pipelineColorBlendStateCreateInfo(
 			blendAttachmentStates.size(),
 			blendAttachmentStates.data()
@@ -398,9 +401,13 @@ void ext::vulkan::Pipeline::record( Graphic& graphic, VkCommandBuffer commandBuf
 	vkCmdBindPipeline(commandBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline);
 }
 void ext::vulkan::Pipeline::update( Graphic& graphic ) {
+	// generate fallback empty texture
+	auto& emptyTexture = Texture2D::empty;
+
 	std::vector<VkWriteDescriptorSet> writeDescriptorSets;
 	std::vector<VkDescriptorSetLayoutBinding> descriptorSetLayoutBindings;
 	std::vector<VkDescriptorImageInfo> inputDescriptors;
+	std::vector<VkDescriptorImageInfo> imageInfos;
 
 	for ( auto& shader : graphic.material.shaders ) {
 		descriptorSetLayoutBindings.insert( descriptorSetLayoutBindings.begin(), shader.descriptorSetLayoutBindings.begin(), shader.descriptorSetLayoutBindings.end() );
@@ -414,6 +421,7 @@ void ext::vulkan::Pipeline::update( Graphic& graphic ) {
 		inputDescriptors.push_back(ext::vulkan::initializers::descriptorImageInfo( 
 			renderTarget.attachments[input.attachment].view,
 			input.layout
+		//	input.layout == VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_READ_ONLY_OPTIMAL : input.layout
 		));
 	}
 	{
@@ -424,42 +432,88 @@ void ext::vulkan::Pipeline::update( Graphic& graphic ) {
 			auto attachments = inputDescriptors.begin();
 
 			for ( auto& layout : shader.descriptorSetLayoutBindings ) {
-				VkDescriptorBufferInfo* bufferInfo = NULL;
+
+				if ( layout.descriptorCount > 1 ) {
+					switch ( layout.descriptorType ) {
+						case VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER:
+						case VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE: {
+							size_t imageInfosStart = imageInfos.size();
+							// assume we have a texture, and fill it in the slots as defaults
+							for ( size_t i = 0; i < layout.descriptorCount; ++i ) {
+								VkDescriptorImageInfo d = emptyTexture.descriptor;
+								if ( textures != graphic.material.textures.end() ) {
+									d = (textures++)->descriptor;
+									if ( layout.descriptorType == VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER && !d.sampler )
+										d.sampler = emptyTexture.sampler.sampler;
+
+								//	if ( d.imageLayout == VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL )
+								//		d.imageLayout = VK_IMAGE_LAYOUT_DEPTH_STENCIL_READ_ONLY_OPTIMAL;
+								}
+								imageInfos.push_back( d );
+							}
+						
+							writeDescriptorSets.push_back(ext::vulkan::initializers::writeDescriptorSet(
+								descriptorSet,
+								layout.descriptorType,
+								layout.binding,
+								&imageInfos[imageInfosStart],
+								imageInfos.size() - imageInfosStart
+							));
+						} break;
+					}
+					continue;
+				}
+
 				VkDescriptorImageInfo* imageInfo = NULL;
 				switch ( layout.descriptorType ) {
 					case VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER:
 					case VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE: {
+						if ( textures == graphic.material.textures.end() ) {
+							imageInfo = &emptyTexture.descriptor;
+							break;
+						}
 						imageInfo = &((textures++)->descriptor);
 					} break;
 					case VK_DESCRIPTOR_TYPE_SAMPLER: {
-						imageInfo = &((samplers++)->descriptor);
+						if ( samplers == graphic.material.samplers.end() ) {
+							std::cout << "samplers == graphic.material.samplers.end()" << std::endl;
+							break;
+						}
+						imageInfo = &((samplers++)->descriptor.info);
 					} break;
 					case VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER: {
-						bufferInfo = &((buffers++)->descriptor);
+						if ( buffers == shader.buffers.end() ) {
+							std::cout << "buffers == shader.buffers.end()" << std::endl;
+							break;
+						}
+						writeDescriptorSets.push_back(ext::vulkan::initializers::writeDescriptorSet(
+							descriptorSet,
+							layout.descriptorType,
+							layout.binding,
+							&((buffers++)->descriptor)
+						));
 					} break;
 					case VK_DESCRIPTOR_TYPE_INPUT_ATTACHMENT: {
+						if ( attachments == inputDescriptors.end() ) {
+							std::cout << "attachments == inputDescriptors.end()" << std::endl;
+							break;
+						}
 						imageInfo = &(*(attachments++));
 					} break;
 				}
-				if ( !bufferInfo && !imageInfo ) continue;
-				if ( bufferInfo )
-					writeDescriptorSets.push_back(ext::vulkan::initializers::writeDescriptorSet(
-						descriptorSet,
-						layout.descriptorType,
-						layout.binding,
-						bufferInfo
-					));
-				else if ( imageInfo ) 
+
+				if ( imageInfo ) {
 					writeDescriptorSets.push_back(ext::vulkan::initializers::writeDescriptorSet(
 						descriptorSet,
 						layout.descriptorType,
 						layout.binding,
 						imageInfo
 					));
+				}
 			}
 		}
 	}
-	
+
 	vkUpdateDescriptorSets(
 		*device,
 		writeDescriptorSets.size(),
diff --git a/engine/src/ext/vulkan/rendermode.cpp b/engine/src/ext/vulkan/rendermode.cpp
index 8dfa3340..c2f053e6 100644
--- a/engine/src/ext/vulkan/rendermode.cpp
+++ b/engine/src/ext/vulkan/rendermode.cpp
@@ -91,6 +91,10 @@ void ext::vulkan::RenderMode::initialize( Device& device ) {
 
 	// this->width = 0; //ext::vulkan::width;
 	// this->height = 0; //ext::vulkan::height;
+	{
+		if ( this->width > 0 ) renderTarget.width = this->width;
+		if ( this->height > 0 ) renderTarget.height = this->height;
+	}
 
 	// Create command buffers
 	{
diff --git a/engine/src/ext/vulkan/rendermodes/deferred.cpp b/engine/src/ext/vulkan/rendermodes/deferred.cpp
index e5179868..f54362f6 100644
--- a/engine/src/ext/vulkan/rendermodes/deferred.cpp
+++ b/engine/src/ext/vulkan/rendermodes/deferred.cpp
@@ -21,13 +21,15 @@ void ext::vulkan::DeferredRenderMode::initialize( Device& device ) {
 		renderTarget.device = &device;
 		// attach targets
 		struct {
-			size_t albedo, position, normals, depth, output;
+			size_t albedo, normals, position, depth, output, ping, pong;
 		} attachments;
 
-		attachments.albedo = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
-		attachments.position = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // position
-		attachments.normals = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // normals
-		attachments.depth = renderTarget.attach( device.formats.depth, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL ); // depth
+		attachments.albedo = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // albedo
+		attachments.normals = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // normals
+		attachments.position = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // position
+		attachments.depth = renderTarget.attach( device.formats.depth, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, true ); // depth
+	//	attachments.ping = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
+	//	attachments.pong = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
 		// Attach swapchain's image as output
 		{
 			attachments.output = renderTarget.attachments.size();
@@ -36,6 +38,23 @@ void ext::vulkan::DeferredRenderMode::initialize( Device& device ) {
 			swapchainAttachment.usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
 			swapchainAttachment.layout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
 			swapchainAttachment.aliased = true;
+			{
+				VkBool32 blendEnabled = VK_TRUE;
+				VkColorComponentFlags writeMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT | VK_COLOR_COMPONENT_A_BIT;
+				VkPipelineColorBlendAttachmentState blendAttachmentState = ext::vulkan::initializers::pipelineColorBlendAttachmentState(
+					writeMask,
+					blendEnabled
+				);
+				if ( blendEnabled == VK_TRUE ) {
+					blendAttachmentState.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
+					blendAttachmentState.dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+					blendAttachmentState.colorBlendOp = VK_BLEND_OP_ADD;
+					blendAttachmentState.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE;
+					blendAttachmentState.dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO;
+					blendAttachmentState.alphaBlendOp = VK_BLEND_OP_ADD;
+				}
+				swapchainAttachment.blendState = blendAttachmentState;
+			}
 			renderTarget.attachments.push_back(swapchainAttachment);
 		}
 
@@ -43,7 +62,7 @@ void ext::vulkan::DeferredRenderMode::initialize( Device& device ) {
 		{
 			renderTarget.addPass(
 				VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
-				{ attachments.albedo, attachments.position, attachments.normals },
+				{ attachments.albedo, attachments.normals, attachments.position },
 				{},
 				attachments.depth
 			);
@@ -53,7 +72,7 @@ void ext::vulkan::DeferredRenderMode::initialize( Device& device ) {
 			renderTarget.addPass(
 				VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, VK_ACCESS_INPUT_ATTACHMENT_READ_BIT,
 				{ attachments.output },
-				{ attachments.albedo, attachments.position, attachments.normals, attachments.depth },
+				{ attachments.albedo, attachments.normals, attachments.position/*, attachments.depth*/ },
 				attachments.depth
 			);
 		}
@@ -63,10 +82,10 @@ void ext::vulkan::DeferredRenderMode::initialize( Device& device ) {
 	{
 		uf::BaseMesh<pod::Vertex_2F2F, uint16_t> mesh;
 		mesh.vertices = {
-			{ {-1.0f, 1.0f}, {0.0f, 0.0f}, },
-			{ {-1.0f, -1.0f}, {0.0f, 1.0f}, },
-			{ {1.0f, -1.0f}, {1.0f, 1.0f}, },
-			{ {1.0f, 1.0f}, {1.0f, 0.0f}, }
+			{ {-1.0f, 1.0f}, {0.0f, 1.0f}, },
+			{ {-1.0f, -1.0f}, {0.0f, 0.0f}, },
+			{ {1.0f, -1.0f}, {1.0f, 0.0f}, },
+			{ {1.0f, 1.0f}, {1.0f, 1.0f}, }
 		};
 		mesh.indices = {
 			0, 1, 2, 0, 2, 3
@@ -169,6 +188,7 @@ void ext::vulkan::DeferredRenderMode::createCommandBuffers( const std::vector<ex
 				RenderTarget& renderTarget = layer->renderTarget;
 				for ( auto& attachment : renderTarget.attachments ) {
 					if ( !(attachment.usage & VK_IMAGE_USAGE_SAMPLED_BIT) ) continue;
+					if (  (attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT) ) continue;
 					imageMemoryBarrier.image = attachment.image;
 					imageMemoryBarrier.srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
 					imageMemoryBarrier.dstAccessMask = VK_ACCESS_MEMORY_READ_BIT | VK_ACCESS_SHADER_READ_BIT;
@@ -218,11 +238,12 @@ void ext::vulkan::DeferredRenderMode::createCommandBuffers( const std::vector<ex
 				RenderTarget& renderTarget = layer->renderTarget;
 				for ( auto& attachment : renderTarget.attachments ) {
 					if ( !(attachment.usage & VK_IMAGE_USAGE_SAMPLED_BIT) ) continue;
+					if (  (attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT) ) continue;
 					imageMemoryBarrier.image = attachment.image;
 					imageMemoryBarrier.srcAccessMask = VK_ACCESS_MEMORY_READ_BIT | VK_ACCESS_SHADER_READ_BIT;
 					imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
 					imageMemoryBarrier.oldLayout = attachment.layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+					imageMemoryBarrier.newLayout = attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL : VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
 					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT , 0, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
 					attachment.layout = imageMemoryBarrier.newLayout;
 				}
diff --git a/engine/src/ext/vulkan/rendermodes/rendertarget.cpp b/engine/src/ext/vulkan/rendermodes/rendertarget.cpp
index b55b9881..a18893eb 100644
--- a/engine/src/ext/vulkan/rendermodes/rendertarget.cpp
+++ b/engine/src/ext/vulkan/rendermodes/rendertarget.cpp
@@ -17,16 +17,16 @@ void ext::vulkan::RenderTargetRenderMode::initialize( Device& device ) {
 	{
 		renderTarget.device = &device;
 		struct {
-			size_t albedo, position, normals, depth, output;
+			size_t albedo, normals, position, depth, output;
 		} attachments;
 
-		attachments.albedo = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
-		attachments.position = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // position
-		attachments.normals = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // normals
-		attachments.depth = renderTarget.attach( device.formats.depth, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL ); // depth
+		attachments.albedo = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // albedo
+		attachments.normals = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // normals
+		attachments.position = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // position
+		attachments.depth = renderTarget.attach( device.formats.depth, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, true ); // depth
 		// Attach swapchain's image as output
 		if ( !false ) {
-			attachments.output = renderTarget.attach( device.formats.color, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_PRESENT_SRC_KHR ); // depth
+			attachments.output = renderTarget.attach( device.formats.color, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_PRESENT_SRC_KHR, true ); // output
 		} else {
 			attachments.output = renderTarget.attachments.size();
 			RenderTarget::Attachment swapchainAttachment;
@@ -34,13 +34,31 @@ void ext::vulkan::RenderTargetRenderMode::initialize( Device& device ) {
 			swapchainAttachment.usage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
 			swapchainAttachment.layout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
 			swapchainAttachment.aliased = true;
+			{
+				VkBool32 blendEnabled = VK_TRUE;
+				VkColorComponentFlags writeMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT | VK_COLOR_COMPONENT_A_BIT;
+				VkPipelineColorBlendAttachmentState blendAttachmentState = ext::vulkan::initializers::pipelineColorBlendAttachmentState(
+					writeMask,
+					blendEnabled
+				);
+				if ( blendEnabled == VK_TRUE ) {
+					blendAttachmentState.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
+					blendAttachmentState.dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+					blendAttachmentState.colorBlendOp = VK_BLEND_OP_ADD;
+					blendAttachmentState.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE;
+					blendAttachmentState.dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO;
+					blendAttachmentState.alphaBlendOp = VK_BLEND_OP_ADD;
+				}
+				swapchainAttachment.blendState = blendAttachmentState;
+			}
 			renderTarget.attachments.push_back(swapchainAttachment);
 		}
+
 		// First pass: write to target
 		{
 			renderTarget.addPass(
 				VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
-				{ attachments.albedo, attachments.position, attachments.normals },
+				{ attachments.albedo, attachments.normals, attachments.position },
 				{},
 				attachments.depth
 			);
@@ -50,7 +68,7 @@ void ext::vulkan::RenderTargetRenderMode::initialize( Device& device ) {
 			renderTarget.addPass(
 				VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, VK_ACCESS_INPUT_ATTACHMENT_READ_BIT,
 				{ attachments.output },
-				{ attachments.albedo, attachments.position, attachments.normals },
+				{ attachments.albedo, attachments.normals, attachments.position/*, attachments.depth*/ },
 				attachments.depth
 			);
 		}
diff --git a/engine/src/ext/vulkan/rendermodes/stereoscopic_deferred.cpp b/engine/src/ext/vulkan/rendermodes/stereoscopic_deferred.cpp
index c4dc51d4..0762c084 100644
--- a/engine/src/ext/vulkan/rendermodes/stereoscopic_deferred.cpp
+++ b/engine/src/ext/vulkan/rendermodes/stereoscopic_deferred.cpp
@@ -11,11 +11,6 @@
 #include <uf/utils/math/transform.h>
 #include <uf/ext/openvr/openvr.h>
 
-namespace {
-	// 0 left 1 right
-	uint8_t DOMINANT_EYE = 0;
-}
-
 // ext::vulkan::StereoscopicDeferredRenderMode::StereoscopicDeferredRenderMode() : renderTargets({ renderTarget }), blitters({ blitter }) {
 ext::vulkan::StereoscopicDeferredRenderMode::StereoscopicDeferredRenderMode() : renderTargets({ renderTarget }) {
 }
@@ -58,16 +53,18 @@ void ext::vulkan::StereoscopicDeferredRenderMode::initialize( Device& device ) {
 		renderTarget.height = this->height;
 		// attach targets
 		struct {
-			size_t albedo, position, normals, depth, output;
+			size_t albedo, normals, position, depth, output;
 		} attachments;
 
-		attachments.albedo = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
-		attachments.position = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // position
-		attachments.normals = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // normals
-		attachments.depth = renderTarget.attach( device.formats.depth, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL ); // depth
-		attachments.output = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_TRANSFER_SRC_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
-		// Attach swapchain's image as output
+		attachments.albedo = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // albedo
+		attachments.normals = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, false ); // normals
+		attachments.position = renderTarget.attach( VK_FORMAT_R16G16B16A16_SFLOAT, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, false ); // position
+		attachments.depth = renderTarget.attach( device.formats.depth, VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL, false ); // depth
+		attachments.output = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_TRANSFER_SRC_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL, true ); // albedo
+	//	attachments.ping = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
+	//	attachments.pong = renderTarget.attach( VK_FORMAT_R8G8B8A8_UNORM, VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT | VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT | VK_IMAGE_USAGE_SAMPLED_BIT, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL ); // albedo
 	/*
+		// Attach swapchain's image as output
 		if ( !true ) {
 			attachments.swapchain = renderTarget.attachments.size();
 			RenderTarget::Attachment swapchainAttachment;
@@ -81,8 +78,8 @@ void ext::vulkan::StereoscopicDeferredRenderMode::initialize( Device& device ) {
 		// First pass: fill the G-Buffer
 		{
 			renderTarget.addPass(
-				VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
-				{ attachments.albedo, attachments.position, attachments.normals },
+				VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_ACCESS_COLOR_ATTACHMENT_READ_BIT | VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
+				{ attachments.albedo, attachments.normals, attachments.position },
 				{},
 				attachments.depth
 			);
@@ -90,9 +87,9 @@ void ext::vulkan::StereoscopicDeferredRenderMode::initialize( Device& device ) {
 		// Second pass: write to output
 		{
 			renderTarget.addPass(
-				VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT,
+				VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, VK_ACCESS_INPUT_ATTACHMENT_READ_BIT,
 				{ attachments.output },
-				{ attachments.albedo, attachments.position, attachments.normals },
+				{ attachments.albedo, attachments.normals, attachments.position/*, attachments.depth*/ },
 				attachments.depth
 			);
 		}
@@ -100,10 +97,10 @@ void ext::vulkan::StereoscopicDeferredRenderMode::initialize( Device& device ) {
 		{
 			uf::BaseMesh<pod::Vertex_2F2F, uint16_t> mesh;
 			mesh.vertices = {
-				{ {-1.0f, 1.0f}, {0.0f, 0.0f}, },
-				{ {-1.0f, -1.0f}, {0.0f, 1.0f}, },
-				{ {1.0f, -1.0f}, {1.0f, 1.0f}, },
-				{ {1.0f, 1.0f}, {1.0f, 0.0f}, }
+				{ {-1.0f, 1.0f}, {0.0f, 1.0f}, },
+				{ {-1.0f, -1.0f}, {0.0f, 0.0f}, },
+				{ {1.0f, -1.0f}, {1.0f, 0.0f}, },
+				{ {1.0f, 1.0f}, {1.0f, 1.0f}, }
 			};
 			mesh.indices = {
 				0, 1, 2, 0, 2, 3
@@ -230,13 +227,17 @@ void ext::vulkan::StereoscopicDeferredRenderMode::createCommandBuffers( const st
 				for ( auto layer : layers ) {
 					if ( layer->getName() == "" ) continue;
 					RenderTarget& renderTarget = layer->renderTarget;
-					imageMemoryBarrier.image = renderTarget.attachments[0].image;
-					imageMemoryBarrier.srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
-					imageMemoryBarrier.dstAccessMask = VK_ACCESS_MEMORY_READ_BIT | VK_ACCESS_SHADER_READ_BIT;
-					imageMemoryBarrier.oldLayout = renderTarget.attachments[0].layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
-					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT , VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, 0, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
-					renderTarget.attachments[0].layout = imageMemoryBarrier.newLayout;
+					for ( auto& attachment : renderTarget.attachments ) {
+						if ( !(attachment.usage & VK_IMAGE_USAGE_SAMPLED_BIT) ) continue;
+						if (  (attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT) ) continue;
+						imageMemoryBarrier.image = attachment.image;
+						imageMemoryBarrier.srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
+						imageMemoryBarrier.dstAccessMask = VK_ACCESS_MEMORY_READ_BIT | VK_ACCESS_SHADER_READ_BIT;
+						imageMemoryBarrier.oldLayout = attachment.layout;
+						imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
+						vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT , VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, 0, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
+						attachment.layout = imageMemoryBarrier.newLayout;
+					}
 				}
 			
 				vkCmdBeginRenderPass(commands[i], &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
@@ -258,7 +259,9 @@ void ext::vulkan::StereoscopicDeferredRenderMode::createCommandBuffers( const st
 						}
 					}
 				vkCmdNextSubpass(commands[i], VK_SUBPASS_CONTENTS_INLINE);
-					blitter.record(commands[i]);
+					{
+						blitter.record(commands[i]);
+					}
 					// render gui layer
 					{
 						for ( auto _ : layers ) {
@@ -269,149 +272,117 @@ void ext::vulkan::StereoscopicDeferredRenderMode::createCommandBuffers( const st
 							blitter.record(commands[i]);
 						}
 					}
-			/*
-				vkCmdNextSubpass(commands[i], VK_SUBPASS_CONTENTS_INLINE);
-				if ( ext::openvr::renderPass == DOMINANT_EYE ) {
-					viewport.width = (float) ::ext::vulkan::width;
-					viewport.height = (float) ::ext::vulkan::height;
-					scissor.extent.width = ::ext::vulkan::width;
-					scissor.extent.height = ::ext::vulkan::height;
-
-					vkCmdSetViewport(commands[i], 0, 1, &viewport);
-					vkCmdSetScissor(commands[i], 0, 1, &scissor);
-					this->blitter.createCommandBuffer(commands[i]);
-					// render gui layer
-					{
-						for ( auto layer : layers ) {
-							if ( layer->getName() == "Gui" ) {
-								RenderTargetRenderMode* guiLayer = (RenderTargetRenderMode*) layer;
-								if ( guiLayer->blitter.subpass == 2 ) guiLayer->blitter.createCommandBuffer(commands[i]);
-							}
-						}
-					}
-				}
-			*/
 				vkCmdEndRenderPass(commands[i]);
 
 				for ( auto layer : layers ) {
 					if ( layer->getName() == "" ) continue;
 					RenderTarget& renderTarget = layer->renderTarget;
-					imageMemoryBarrier.image = renderTarget.attachments[0].image;
-					imageMemoryBarrier.srcAccessMask = VK_ACCESS_MEMORY_READ_BIT | VK_ACCESS_SHADER_READ_BIT;
-					imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
-					imageMemoryBarrier.oldLayout = renderTarget.attachments[0].layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
-					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT , 0, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
-					renderTarget.attachments[0].layout = imageMemoryBarrier.newLayout;
+					for ( auto& attachment : renderTarget.attachments ) {
+						if ( !(attachment.usage & VK_IMAGE_USAGE_SAMPLED_BIT) ) continue;
+						if (  (attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT) ) continue;
+						imageMemoryBarrier.image = attachment.image;
+						imageMemoryBarrier.srcAccessMask = VK_ACCESS_MEMORY_READ_BIT | VK_ACCESS_SHADER_READ_BIT;
+						imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
+						imageMemoryBarrier.oldLayout = attachment.layout;
+						imageMemoryBarrier.newLayout = attachment.usage & VK_IMAGE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL : VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+						vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT , 0, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
+						attachment.layout = imageMemoryBarrier.newLayout;
+					}
 				}
 			}
-		}
-		// Blit eye to swapchain
-		{
-		//	if ( false ) {
-			auto& swapchainRender = ext::vulkan::getRenderMode("Swapchain");
-			{
-				auto& renderTarget = swapchainRender.renderTarget;
-				float width = renderTarget.width;
-				float height = renderTarget.height;
-
-				std::vector<VkClearValue> clearValues; clearValues.resize(2);
-				clearValues[0].color = { { 0.0f, 0.0f, 0.0f, 1.0f } };
-				clearValues[1].depthStencil = { 1.0f, 0 };
-
-				VkRenderPassBeginInfo renderPassBeginInfo = {};
-				renderPassBeginInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
-				renderPassBeginInfo.pNext = nullptr;
-				renderPassBeginInfo.renderArea.offset.x = 0;
-				renderPassBeginInfo.renderArea.offset.y = 0;
-				renderPassBeginInfo.renderArea.extent.width = width;
-				renderPassBeginInfo.renderArea.extent.height = height;
-				renderPassBeginInfo.clearValueCount = clearValues.size();
-				renderPassBeginInfo.pClearValues = &clearValues[0];
-				renderPassBeginInfo.renderPass = renderTarget.renderPass;
-				renderPassBeginInfo.framebuffer = renderTarget.framebuffers[i];
-				
-				// Update dynamic viewport state
-				VkViewport viewport = {};
-				viewport.width = (float) width;
-				viewport.height = (float) height;
-				viewport.minDepth = (float) 0.0f;
-				viewport.maxDepth = (float) 1.0f;
-				
-				// Update dynamic scissor state
-				VkRect2D scissor = {};
-				scissor.extent.width = width;
-				scissor.extent.height = height;
-				scissor.offset.x = 0;
-				scissor.offset.y = 0;
-
-				vkCmdBeginRenderPass(commands[i], &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
-				vkCmdEndRenderPass(commands[i]);
-
-			}
-			{
-				auto& renderTarget = DOMINANT_EYE == 0 ? renderTargets.left : renderTargets.right;
-				VkImageBlit imageBlitRegion{};
-				imageBlitRegion.srcSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
-				imageBlitRegion.srcSubresource.layerCount = 1;
-				imageBlitRegion.srcOffsets[1] = { width, height, 1 };
-				imageBlitRegion.dstSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
-				imageBlitRegion.dstSubresource.layerCount = 1;
-				imageBlitRegion.dstOffsets[1] = {
-					swapchainRender.width > 0 ? swapchainRender.width : ext::vulkan::width,
-					swapchainRender.height > 0 ? swapchainRender.height : ext::vulkan::height,
-					1
-				};
-
-				auto& outputAttachment = renderTarget.attachments[renderTarget.attachments.size()-1];
-				// Transition to KHR
+			// Blit eye to swapchain
+			if ( ext::openvr::dominantEye == ext::openvr::renderPass ) {
+			//	if ( false ) {
+				// transition swapchain to proper layout
+				auto& swapchainRender = ext::vulkan::getRenderMode("Swapchain");
 				{
-					imageMemoryBarrier.image = outputAttachment.image;
-					imageMemoryBarrier.srcAccessMask = 0;
-					imageMemoryBarrier.dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
-					imageMemoryBarrier.oldLayout = outputAttachment.layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL;
-					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_ALL_GRAPHICS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
-					outputAttachment.layout = imageMemoryBarrier.newLayout;
-				}
-				{
-					imageMemoryBarrier.image = swapchainRender.renderTarget.attachments[i].image;
-					imageMemoryBarrier.srcAccessMask = 0;
-					imageMemoryBarrier.dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
-					imageMemoryBarrier.oldLayout = swapchainRender.renderTarget.attachments[i].layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
-					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_ALL_GRAPHICS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
-					swapchainRender.renderTarget.attachments[i].layout = imageMemoryBarrier.newLayout;
+					auto& renderTarget = swapchainRender.renderTarget;
+					float width = renderTarget.width;
+					float height = renderTarget.height;
+
+					std::vector<VkClearValue> clearValues; clearValues.resize(2);
+					clearValues[0].color = { { 0.0f, 0.0f, 0.0f, 1.0f } };
+					clearValues[1].depthStencil = { 1.0f, 0 };
+
+					VkRenderPassBeginInfo renderPassBeginInfo = {};
+					renderPassBeginInfo.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
+					renderPassBeginInfo.pNext = nullptr;
+					renderPassBeginInfo.renderArea.offset.x = 0;
+					renderPassBeginInfo.renderArea.offset.y = 0;
+					renderPassBeginInfo.renderArea.extent.width = width;
+					renderPassBeginInfo.renderArea.extent.height = height;
+					renderPassBeginInfo.clearValueCount = clearValues.size();
+					renderPassBeginInfo.pClearValues = &clearValues[0];
+					renderPassBeginInfo.renderPass = renderTarget.renderPass;
+					renderPassBeginInfo.framebuffer = renderTarget.framebuffers[i];
+
+					vkCmdBeginRenderPass(commands[i], &renderPassBeginInfo, VK_SUBPASS_CONTENTS_INLINE);
+					vkCmdEndRenderPass(commands[i]);
 				}
 
-				vkCmdBlitImage(
-					commands[i],
-					outputAttachment.image,
-					VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
-					swapchainRender.renderTarget.attachments[i].image,
-					VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
-					1,
-					&imageBlitRegion,
-					VK_FILTER_LINEAR
-				);
+				{
+					VkImageBlit imageBlitRegion{};
+					imageBlitRegion.srcSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
+					imageBlitRegion.srcSubresource.layerCount = 1;
+					imageBlitRegion.srcOffsets[1] = { width, height, 1 };
+					imageBlitRegion.dstSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
+					imageBlitRegion.dstSubresource.layerCount = 1;
+					imageBlitRegion.dstOffsets[1] = {
+						swapchainRender.width > 0 ? swapchainRender.width : ext::vulkan::width,
+						swapchainRender.height > 0 ? swapchainRender.height : ext::vulkan::height,
+						1
+					};
 
-				{
-					imageMemoryBarrier.image = outputAttachment.image;
-					imageMemoryBarrier.srcAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
-					imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
-					imageMemoryBarrier.oldLayout = outputAttachment.layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
-					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
-					outputAttachment.layout = imageMemoryBarrier.newLayout;
-				}
-				{
-					imageMemoryBarrier.image = swapchainRender.renderTarget.attachments[i].image;
-					imageMemoryBarrier.srcAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
-					imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
-					imageMemoryBarrier.oldLayout = swapchainRender.renderTarget.attachments[i].layout;
-					imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
-					vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
-					swapchainRender.renderTarget.attachments[i].layout = imageMemoryBarrier.newLayout;
+					auto& outputAttachment = renderTarget.attachments[renderTarget.attachments.size()-1];
+					// Transition to KHR
+					{
+						imageMemoryBarrier.image = outputAttachment.image;
+						imageMemoryBarrier.srcAccessMask = 0;
+						imageMemoryBarrier.dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
+						imageMemoryBarrier.oldLayout = outputAttachment.layout;
+						imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL;
+						vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_ALL_GRAPHICS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
+						outputAttachment.layout = imageMemoryBarrier.newLayout;
+					}
+					{
+						imageMemoryBarrier.image = swapchainRender.renderTarget.attachments[i].image;
+						imageMemoryBarrier.srcAccessMask = 0;
+						imageMemoryBarrier.dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
+						imageMemoryBarrier.oldLayout = swapchainRender.renderTarget.attachments[i].layout;
+						imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
+						vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_ALL_GRAPHICS_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
+						swapchainRender.renderTarget.attachments[i].layout = imageMemoryBarrier.newLayout;
+					}
+
+					vkCmdBlitImage(
+						commands[i],
+						outputAttachment.image,
+						VK_IMAGE_LAYOUT_TRANSFER_SRC_OPTIMAL,
+						swapchainRender.renderTarget.attachments[i].image,
+						VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
+						1,
+						&imageBlitRegion,
+						VK_FILTER_LINEAR
+					);
+
+					{
+						imageMemoryBarrier.image = outputAttachment.image;
+						imageMemoryBarrier.srcAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
+						imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
+						imageMemoryBarrier.oldLayout = outputAttachment.layout;
+						imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+						vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
+						outputAttachment.layout = imageMemoryBarrier.newLayout;
+					}
+					{
+						imageMemoryBarrier.image = swapchainRender.renderTarget.attachments[i].image;
+						imageMemoryBarrier.srcAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
+						imageMemoryBarrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
+						imageMemoryBarrier.oldLayout = swapchainRender.renderTarget.attachments[i].layout;
+						imageMemoryBarrier.newLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
+						vkCmdPipelineBarrier( commands[i], VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_DEPENDENCY_BY_REGION_BIT, 0, NULL, 0, NULL, 1, &imageMemoryBarrier );
+						swapchainRender.renderTarget.attachments[i].layout = imageMemoryBarrier.newLayout;
+					}
 				}
 			}
 		}
diff --git a/engine/src/ext/vulkan/rendertarget.cpp b/engine/src/ext/vulkan/rendertarget.cpp
index feee97d4..cf78e57d 100644
--- a/engine/src/ext/vulkan/rendertarget.cpp
+++ b/engine/src/ext/vulkan/rendertarget.cpp
@@ -13,10 +13,11 @@ void ext::vulkan::RenderTarget::addPass( VkPipelineStageFlags stage, VkAccessFla
 	pass.access = access;
 	for ( auto& i : colors ) pass.colors.push_back( { (uint32_t) i, VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL } );
 	for ( auto& i : inputs ) pass.inputs.push_back( { (uint32_t) i, i == depth ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_READ_ONLY_OPTIMAL : VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL } );
+//	for ( auto& i : inputs ) pass.inputs.push_back( { (uint32_t) i, i == depth ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL : VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL } );
 	if ( depth < attachments.size() ) pass.depth = { (uint32_t) depth, attachments[depth].layout };
 	passes.push_back(pass);
 }
-size_t ext::vulkan::RenderTarget::attach( VkFormat format, VkImageUsageFlags usage, VkImageLayout layout, Attachment* attachment ) {
+size_t ext::vulkan::RenderTarget::attach( VkFormat format, VkImageUsageFlags usage, VkImageLayout layout, bool blend, Attachment* attachment ) {
 	uint32_t width = this->width > 0 ? this->width : ext::vulkan::width;
 	uint32_t height = this->height > 0 ? this->height : ext::vulkan::height;
 
@@ -98,6 +99,30 @@ size_t ext::vulkan::RenderTarget::attach( VkFormat format, VkImageUsageFlags usa
 
 	VK_CHECK_RESULT(vkCreateImageView(*device, &imageView, nullptr, &attachment->view));
 
+	{
+		VkBool32 blendEnabled = VK_FALSE;
+		VkColorComponentFlags writeMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT;
+
+		if ( blend ) {
+			blendEnabled = VK_TRUE;
+			writeMask |= VK_COLOR_COMPONENT_A_BIT;
+		}
+
+		VkPipelineColorBlendAttachmentState blendAttachmentState = ext::vulkan::initializers::pipelineColorBlendAttachmentState(
+			writeMask,
+			blendEnabled
+		);
+		if ( blendEnabled == VK_TRUE ) {
+			blendAttachmentState.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
+			blendAttachmentState.dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+			blendAttachmentState.colorBlendOp = VK_BLEND_OP_ADD;
+			blendAttachmentState.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE;
+			blendAttachmentState.dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO;
+			blendAttachmentState.alphaBlendOp = VK_BLEND_OP_ADD;
+		}
+		attachment->blendState = blendAttachmentState;
+	}
+
 	return attachments.size()-1;
 }
 void ext::vulkan::RenderTarget::initialize( Device& device ) {
@@ -112,7 +137,8 @@ void ext::vulkan::RenderTarget::initialize( Device& device ) {
 	if ( initialized ) {
 		for ( auto& attachment: this->attachments ) {
 			if ( attachment.aliased ) continue;
-			attach( attachment.format, attachment.usage, attachment.layout, &attachment );
+			bool blend = attachment.blendState.blendEnable == VK_TRUE;
+			attach( attachment.format, attachment.usage, attachment.layout, blend, &attachment );
 		}
 	}
 	// ensure attachments are already created
@@ -131,7 +157,7 @@ void ext::vulkan::RenderTarget::initialize( Device& device ) {
 			description.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
 			description.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
 			description.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
-			description.finalLayout = attachment.layout;
+			description.finalLayout = attachment.layout == VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL ? VK_IMAGE_LAYOUT_DEPTH_STENCIL_READ_ONLY_OPTIMAL : attachment.layout;
 			description.flags = 0;
 
 			attachments.push_back(description);
@@ -191,6 +217,39 @@ void ext::vulkan::RenderTarget::initialize( Device& device ) {
 			dependency.dstAccessMask = VK_ACCESS_MEMORY_READ_BIT;
 			dependencies.push_back(dependency);
 		}
+
+		// depth dependency
+		{
+			VkSubpassDependency dependency;
+			dependency.dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;
+
+			
+			dependency.srcSubpass = VK_SUBPASS_EXTERNAL;
+			dependency.srcStageMask = VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT;
+			dependency.srcAccessMask = VK_ACCESS_SHADER_READ_BIT;
+
+			dependency.dstSubpass = 0;
+			dependency.dstStageMask = VK_PIPELINE_STAGE_EARLY_FRAGMENT_TESTS_BIT;
+			dependency.dstAccessMask = VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT;
+			
+			dependencies.push_back(dependency);
+		}
+		{
+			VkSubpassDependency dependency;
+			dependency.dependencyFlags = VK_DEPENDENCY_BY_REGION_BIT;
+
+			
+			dependency.srcSubpass = 0;
+			dependency.srcStageMask = VK_PIPELINE_STAGE_LATE_FRAGMENT_TESTS_BIT;
+			dependency.srcAccessMask = VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT;
+
+			dependency.dstSubpass = i == 1 ? VK_SUBPASS_EXTERNAL : 1;
+			dependency.dstStageMask = VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT;
+			dependency.dstAccessMask = VK_ACCESS_SHADER_READ_BIT;
+			
+			dependencies.push_back(dependency);
+		}
+
 	/*
 		for ( auto& dependency : dependencies  ) {
 			std::cout << "Pass: " << dependency.srcSubpass << " -> " << dependency.dstSubpass << std::endl;
diff --git a/engine/src/ext/vulkan/texture.cpp b/engine/src/ext/vulkan/texture.cpp
index 23e92522..eb447fab 100644
--- a/engine/src/ext/vulkan/texture.cpp
+++ b/engine/src/ext/vulkan/texture.cpp
@@ -3,29 +3,30 @@
 #include <uf/utils/image/image.h>
 #include <uf/ext/vulkan/vulkan.h>
 
-void ext::vulkan::Sampler::initialize( Device& device, VkFilter filter ) {
+ext::vulkan::Texture2D ext::vulkan::Texture2D::empty;
+
+void ext::vulkan::Sampler::initialize( Device& device ) {
 	this->device = &device;
-	this->filter = filter;
 
 	{
 		VkSamplerCreateInfo samplerCreateInfo = {};
 		samplerCreateInfo.sType = VK_STRUCTURE_TYPE_SAMPLER_CREATE_INFO;
-		samplerCreateInfo.magFilter = filter;
-		samplerCreateInfo.minFilter = filter;
-		samplerCreateInfo.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
-		samplerCreateInfo.addressModeU = VK_SAMPLER_ADDRESS_MODE_REPEAT;
-		samplerCreateInfo.addressModeV = VK_SAMPLER_ADDRESS_MODE_REPEAT;
-		samplerCreateInfo.addressModeW = VK_SAMPLER_ADDRESS_MODE_REPEAT;
-		samplerCreateInfo.mipLodBias = 0.0f;
-		samplerCreateInfo.compareOp = VK_COMPARE_OP_NEVER;
-		samplerCreateInfo.minLod = 0.0f;
-		samplerCreateInfo.maxLod = 0.0f;
-		samplerCreateInfo.maxAnisotropy = 1.0f;
+		samplerCreateInfo.minFilter = descriptor.filter.min;
+		samplerCreateInfo.magFilter = descriptor.filter.mag;
+		samplerCreateInfo.addressModeU = descriptor.addressMode.u;
+		samplerCreateInfo.addressModeV = descriptor.addressMode.v;
+		samplerCreateInfo.addressModeW = descriptor.addressMode.w;
+
+		samplerCreateInfo.mipmapMode = descriptor.mip.mode;
+		samplerCreateInfo.mipLodBias = descriptor.mip.lodBias;
+		samplerCreateInfo.compareOp = descriptor.compareOp;
+		samplerCreateInfo.minLod = descriptor.lod.min;
+		samplerCreateInfo.maxLod = descriptor.lod.max;
+		samplerCreateInfo.maxAnisotropy = descriptor.maxAnisotropy;
 		VK_CHECK_RESULT(vkCreateSampler(device.logicalDevice, &samplerCreateInfo, nullptr, &sampler));
 	}
-
 	{
-		descriptor.sampler = sampler;
+		descriptor.info.sampler = sampler;
 	}
 }
 void ext::vulkan::Sampler::destroy() {
@@ -274,7 +275,6 @@ void ext::vulkan::Texture2D::loadFromFile(
 		image.getDimensions()[1],
 		device,
 		copyQueue,
-		sampler.filter,
 		imageUsageFlags,
 		imageLayout
 	);
@@ -347,7 +347,6 @@ void ext::vulkan::Texture2D::loadFromImage(
 		image.getDimensions()[1],
 		device,
 		copyQueue,
-		sampler.filter,
 		imageUsageFlags,
 		imageLayout
 	);
@@ -360,7 +359,6 @@ void ext::vulkan::Texture2D::fromBuffers(
 	uint32_t texHeight,
 	Device& device,
 	VkQueue copyQueue,
-	VkFilter filter,
 	VkImageUsageFlags imageUsageFlags,
 	VkImageLayout imageLayout
 ) {
@@ -466,7 +464,7 @@ void ext::vulkan::Texture2D::fromBuffers(
 	staging.destroy();
 	
 	// Create sampler
-	sampler.initialize( device, sampler.filter );
+	sampler.initialize( device );
 
 	// Create image view
 	VkImageViewCreateInfo viewCreateInfo = {};
@@ -535,7 +533,7 @@ void ext::vulkan::Texture2D::asRenderTarget( Device& device, uint32_t width, uin
 	device.flushCommandBuffer(layoutCmd, copyQueue, true);
 
 	// Create sampler
-	sampler.initialize( device, sampler.filter );
+	sampler.initialize( device );
 
 	// Create image view
 	VkImageViewCreateInfo viewCreateInfo = ext::vulkan::initializers::imageViewCreateInfo();
@@ -556,7 +554,7 @@ void ext::vulkan::Texture2D::aliasAttachment( const RenderTarget::Attachment& at
 	deviceMemory = attachment.mem;
 
 	// Create sampler
-	if ( createSampler ) sampler.initialize( ext::vulkan::device, sampler.filter );
+	if ( createSampler ) sampler.initialize( ext::vulkan::device );
 	
 	this->updateDescriptors();
 }
\ No newline at end of file
diff --git a/engine/src/ext/vulkan/vulkan.cpp b/engine/src/ext/vulkan/vulkan.cpp
index b233f325..82fb5492 100644
--- a/engine/src/ext/vulkan/vulkan.cpp
+++ b/engine/src/ext/vulkan/vulkan.cpp
@@ -12,6 +12,8 @@ uint32_t ext::vulkan::width = 1280;
 uint32_t ext::vulkan::height = 720;
 
 bool ext::vulkan::validation = true;
+std::vector<std::string> ext::vulkan::validationFilters;
+std::vector<std::string> ext::vulkan::requestedDeviceFeatures;
 ext::vulkan::Device ext::vulkan::device;
 ext::vulkan::Allocator ext::vulkan::allocator;
 ext::vulkan::Swapchain ext::vulkan::swapchain;
@@ -46,7 +48,11 @@ VKAPI_ATTR VkBool32 VKAPI_CALL ext::vulkan::debugCallback(
 	void* pUserData
 ) {
 	if ( messageSeverity <= VK_DEBUG_UTILS_MESSAGE_SEVERITY_WARNING_BIT_EXT )  return VK_FALSE;
-	uf::iostream << "[Validation Layer] " << pCallbackData->pMessage << "\n";
+	std::string message = pCallbackData->pMessage;
+	for ( auto& filter : ext::vulkan::validationFilters ) {
+		if ( message.find(filter) != std::string::npos ) return VK_FALSE;
+	}
+	uf::iostream << "[Validation Layer] " << message << "\n";
 	return VK_FALSE;
 }
 
@@ -220,6 +226,15 @@ void ext::vulkan::initialize( uint8_t stage ) {
 				allocatorInfo.device = device.logicalDevice;
 				vmaCreateAllocator(&allocatorInfo, &allocator);
 			}
+			{
+				std::vector<uint8_t> pixels = { 
+					255,   0, 255, 255,      0,   0,   0, 255,
+					  0,   0,   0, 255,    255,   0, 255, 255,
+				};
+				Texture2D::empty.sampler.descriptor.filter.min = VK_FILTER_NEAREST;
+				Texture2D::empty.sampler.descriptor.filter.mag = VK_FILTER_NEAREST;
+				Texture2D::empty.fromBuffers( (void*) &pixels[0], pixels.size(), VK_FORMAT_R8G8B8A8_UNORM, 2, 2, ext::vulkan::device, ext::vulkan::device.graphicsQueue, VK_IMAGE_USAGE_SAMPLED_BIT );
+			}
 			for ( auto& renderMode : renderModes ) {
 				if ( !renderMode ) continue;
 				renderMode->initialize(device);
@@ -234,14 +249,7 @@ void ext::vulkan::initialize( uint8_t stage ) {
 				if ( !entity->hasComponent<uf::Graphic>() ) return;
 				ext::vulkan::Graphic& graphic = entity->getComponent<uf::Graphic>();
 				if ( graphic.initialized ) return;
-			/*
-				if ( !entity->hasComponent<uf::Mesh>() ) return;
-				uf::MeshBase& mesh = entity->getComponent<uf::Mesh>();
-				ext::vulkan::Graphic& graphic = mesh.graphic;
-				if ( !mesh.generated ) return;
-				if ( !graphic.process ) return;
-				if ( graphic.initialized ) return;
-			*/
+
 				graphic.initializePipeline();
 				ext::vulkan::rebuild = true;
 			};
@@ -269,12 +277,7 @@ void ext::vulkan::tick() {
 		if ( !entity->hasComponent<uf::Graphic>() ) return;
 		ext::vulkan::Graphic& graphic = entity->getComponent<uf::Graphic>();
 		if ( graphic.initialized ) return;
-	/*
-		if ( !entity->hasComponent<uf::Mesh>() ) return;
-		uf::MeshBase& mesh = entity->getComponent<uf::Mesh>();
-		ext::vulkan::Graphic& graphic = mesh.graphic;
-		if ( !mesh.generated ) return;
-	*/
+
 		if ( !graphic.process ) return;
 		if ( graphic.initialized ) return;
 		graphic.initializePipeline();
@@ -320,6 +323,8 @@ void ext::vulkan::destroy() {
 	ext::vulkan::mutex.lock();
 	vkDeviceWaitIdle( device );
 
+	Texture2D::empty.destroy();
+
 	std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
 		if ( !entity->hasComponent<uf::Graphic>() ) return;
 		uf::Graphic& graphic = entity->getComponent<uf::Graphic>();
diff --git a/engine/src/utils/camera/camera.cpp b/engine/src/utils/camera/camera.cpp
index 98f90e37..c7a1361f 100644
--- a/engine/src/utils/camera/camera.cpp
+++ b/engine/src/utils/camera/camera.cpp
@@ -18,6 +18,7 @@ uf::Camera::Camera() :
 	this->m_settings.offset = {0, 0, 0};
 	this->m_settings.mode = 1;
 	
+	this->setModel(uf::matrix::identity());
 	this->setView(uf::matrix::identity());
 	this->setProjection(uf::matrix::identity());
 	
@@ -61,6 +62,7 @@ const pod::Transform<>& uf::Camera::getTransform() const {
 }
 
 pod::Matrix4& uf::Camera::getView( size_t eye ) {
+	// if ( !this->m_settings.stereoscopic ) eye = 0;
 	switch ( eye ) {
 		case 0:
 			return this->m_matrices.left.view;
@@ -80,6 +82,7 @@ pod::Matrix4& uf::Camera::getView( size_t eye ) {
 */
 }
 pod::Matrix4& uf::Camera::getProjection( size_t eye ) {
+	// if ( !this->m_settings.stereoscopic ) eye = 0;
 	switch ( eye ) {
 		case 0:
 			return this->m_matrices.left.projection;
@@ -103,6 +106,7 @@ pod::Matrix4& uf::Camera::getModel() {
 }
 
 const pod::Matrix4& uf::Camera::getView( size_t eye ) const {
+	// if ( !this->m_settings.stereoscopic ) eye = 0;
 	switch ( eye ) {
 		case 0:
 			return this->m_matrices.left.view;
@@ -122,6 +126,7 @@ const pod::Matrix4& uf::Camera::getView( size_t eye ) const {
 */
 }
 const pod::Matrix4& uf::Camera::getProjection( size_t eye ) const {
+	// if ( !this->m_settings.stereoscopic ) eye = 0;
 	switch ( eye ) {
 		case 0:
 			return this->m_matrices.left.projection;
@@ -177,6 +182,7 @@ void uf::Camera::setTransform( const pod::Transform<>& transform ) {
 	this->update(true);
 }
 void uf::Camera::setView( const pod::Matrix4& mat, size_t i ) {
+	// if ( !this->m_settings.stereoscopic ) i = 2;
 	switch ( i ) {
 		case 0:
 			this->m_matrices.left.view = mat;
@@ -191,6 +197,7 @@ void uf::Camera::setView( const pod::Matrix4& mat, size_t i ) {
 	}
 }
 void uf::Camera::setProjection( const pod::Matrix4& mat, size_t i ) {
+	// if ( !this->m_settings.stereoscopic ) i = 2;
 	switch ( i ) {
 		case 0:
 			this->m_matrices.left.projection = mat;
@@ -235,7 +242,9 @@ void uf::Camera::ortho( const pod::Vector2& lr, const pod::Vector2& bt, const po
 
 	this->update(true);
 }
-
+void uf::Camera::setStereoscopic(bool settings) {
+	this->m_settings.stereoscopic = settings;
+}
 void uf::Camera::update(bool override) {
 	if ( !override && !this->modified() ) return;
 	this->updateView();
@@ -243,7 +252,7 @@ void uf::Camera::update(bool override) {
 	this->m_modified = true;
 }
 void uf::Camera::updateView() {
-	if ( ext::openvr::context ) {
+	if ( this->m_settings.stereoscopic && ext::openvr::context ) {
 		pod::Transform<>& transform = this->getTransform();
 		pod::Vector3t<> position = transform.position;
 		if ( transform.reference ) position += transform.reference->position;
@@ -251,9 +260,10 @@ void uf::Camera::updateView() {
 
 		pod::Transform<> flatten = uf::transform::flatten( transform );
 		pod::Matrix4t<> translation = uf::matrix::translate( uf::matrix::identity(), position );
-		pod::Matrix4t<> rotation = uf::quaternion::matrix( flatten.orientation );
+		pod::Matrix4t<> rotation = uf::quaternion::matrix( flatten.orientation * pod::Vector4f{1,1,1,-1} );
 
 		pod::Matrix4t<> view = uf::matrix::inverse( translation * rotation );
+
 		transform.orientation = ext::openvr::hmdQuaternion();
 		this->setView( ext::openvr::hmdViewMatrix(vr::Eye_Left, view ), 0 );
 		this->setView( ext::openvr::hmdViewMatrix(vr::Eye_Right, view ), 1 );
@@ -301,8 +311,11 @@ void uf::Camera::updateView() {
 		pod::Matrix4t<> translation = uf::matrix::translate( uf::matrix::identity(), position * -1 );
 		pod::Transform<> flatten = uf::transform::flatten(transform, true);
 		pod::Matrix4t<> rotation = uf::quaternion::matrix( flatten.orientation );
+		pod::Matrix4t<> scale = uf::matrix::inverse( uf::matrix::scale( uf::matrix::identity(), transform.scale ) );
 
-		this->setView(rotation * translation);
+		// std::cout << transform.scale.x << ", " << transform.scale.y << ", " << transform.scale.z << std::endl;
+
+		this->setView(rotation * translation * scale);
 	/*
 		pod::Transform<> transform = this->getTransform();
 		if ( transform.reference ) transform.position += transform.reference->position;
@@ -316,7 +329,7 @@ void uf::Camera::updateView() {
 	}
 }
 void uf::Camera::updateProjection() {
-	if ( ext::openvr::context ) {
+	if ( this->m_settings.stereoscopic && ext::openvr::context ) {
 	//	::projection.left = ext::openvr::hmdProjectionMatrix( vr::Eye_Left, this->m_settings.perspective.bounds.x, this->m_settings.perspective.bounds.y );
 	//	::projection.right = ext::openvr::hmdProjectionMatrix( vr::Eye_Right, this->m_settings.perspective.bounds.x, this->m_settings.perspective.bounds.y );
 		this->setProjection( ext::openvr::hmdProjectionMatrix( vr::Eye_Left, this->m_settings.perspective.bounds.x, this->m_settings.perspective.bounds.y ), 0 );
diff --git a/engine/src/utils/image/image.cpp b/engine/src/utils/image/image.cpp
index a98db80d..be6cebcc 100644
--- a/engine/src/utils/image/image.cpp
+++ b/engine/src/utils/image/image.cpp
@@ -4,6 +4,10 @@
 #include <fstream> 					// std::fstream
 #include <iostream> 				// std::fstream
 #include <png/png.h> 				// libpng
+
+#define STB_IMAGE_IMPLEMENTATION
+#include <gltf/stb_image.h>
+
 // 	C-tor
 // Default
 uf::Image::Image() :
@@ -58,9 +62,6 @@ uf::Image::Image( const Image::container_t& copy, const Image::vec2_t& size ) :
 
 }
 
-#define STB_IMAGE_IMPLEMENTATION
-#include <stb_image.h>
-
 std::string uf::Image::getFilename() const {
 	return this->m_filename;
 }
@@ -189,7 +190,7 @@ bool uf::Image::open( const std::string& filename ) {
 	}
 	return true;
 }
-void uf::Image::loadFromBuffer( const Image::pixel_t::type_t* pointer, const pod::Vector2ui& size, std::size_t bit_depth, std::size_t channels ) {
+void uf::Image::loadFromBuffer( const Image::pixel_t::type_t* pointer, const pod::Vector2ui& size, std::size_t bit_depth, std::size_t channels, bool flip ) {
 	this->m_dimensions = size;
 	this->m_bpp = bit_depth * channels;
 	this->m_channels = channels;
@@ -199,6 +200,20 @@ void uf::Image::loadFromBuffer( const Image::pixel_t::type_t* pointer, const pod
 	this->m_pixels.resize( len );
 	//for ( size_t i = 0; i < len; ++i ) this->m_pixels[i] = pointer[i];
 	memcpy( &this->m_pixels[0], pointer, len );
+
+	if ( flip ) {
+		auto w = this->m_dimensions.x;
+		auto h = this->m_dimensions.y;
+		uint8_t* pixels = &this->m_pixels[0];
+		for (uint j = 0; j * 2 < h; ++j) {
+			uint x = j * w * this->m_bpp/8;
+			uint y = (h - 1 - j) * w * this->m_bpp/8;
+			for (uint i = w * this->m_bpp/8; i > 0; --i) {
+				std::swap( pixels[x], pixels[y] );
+				++x, ++y;
+			}
+		}
+	}
 }
 void uf::Image::loadFromBuffer( const Image::container_t& container, const pod::Vector2ui& size, std::size_t bit_depth, std::size_t channels, bool flip ) {
 	this->m_dimensions = size;
@@ -206,10 +221,10 @@ void uf::Image::loadFromBuffer( const Image::container_t& container, const pod::
 	this->m_channels = channels;
 	this->m_pixels = container;
 
-	uint8_t* pixels = &this->m_pixels[0];
 	if ( flip ) {
 		auto w = this->m_dimensions.x;
 		auto h = this->m_dimensions.y;
+		uint8_t* pixels = &this->m_pixels[0];
 		for (uint j = 0; j * 2 < h; ++j) {
 			uint x = j * w * this->m_bpp/8;
 			uint y = (h - 1 - j) * w * this->m_bpp/8;
diff --git a/engine/src/utils/math/collider.cpp b/engine/src/utils/math/collider.cpp
index cb5e81eb..e5db8fe1 100644
--- a/engine/src/utils/math/collider.cpp
+++ b/engine/src/utils/math/collider.cpp
@@ -1,446 +1,62 @@
 #include <uf/utils/math/collision.h>
+#include <uf/utils/math/collision/gjk.h>
+#include <uf/utils/math/collision/boundingbox.h>
+#include <uf/utils/math/collision/sphere.h>
+#include <uf/utils/math/collision/mesh.h>
+#include <uf/utils/math/collision/modular.h>
 #include <iostream>
 
-/*
-pod::Simplex::Simplex( const pod::Vector3& b, const pod::Vector3& c, const pod::Vector3& d ) {
-	this->set(b, c, d);
-}
-void pod::Simplex::add( const pod::Vector3& a ) {
-	this->d = this->c;
-	this->c = this->b;
-	this->b = a;
-}
-void pod::Simplex::set( const pod::Vector3& b, const pod::Vector3& c, const pod::Vector3& d ) {
-	this->b = b;
-	this->c = c;
-	this->d = d;
-	if ( b != pod::Vector3{} ) this->size++;
-	if ( c != pod::Vector3{} ) this->size++;
-	if ( d != pod::Vector3{} ) this->size++;
-}
-*/
-uf::Collider::~Collider(){}
-std::string UF_API uf::Collider::type() const { return ""; }
-uf::Collider::Manifold UF_API uf::Collider::intersects( const uf::Collider& y ) const {
-	const uf::Collider& x = *this;
-	pod::Simplex simplex;
-	pod::Vector3 direction = pod::Vector3{ 1.0f, 0.0f, 0.0f };
-	
-	uf::Collider::Manifold manifold(x, y);
-	double dot = -0.1;
-	uint iterations = 0;
-	uint iterations_cap = 25;
-	while ( iterations++ < iterations_cap ) {
-		direction = uf::vector::normalize(direction);
-
-		pod::Simplex::SupportPoint a;
-		a.a = x.support(direction);
-		a.b = y.support(-direction);
-		a.v = a.a - a.b;
-
-		if ( (dot = a.dot(direction)) < 0 ) {
-			return manifold;
-		}
-		if( simplex.size == 0 ) {	
-			simplex.b = a;
-
-			direction = direction * -1;
-			simplex.size = 1;
-			continue;
-		}
-		if ( simplex.size == 1 ) {
-			direction = uf::vector::cross(a.cross(simplex.b), a.v);
-			simplex.c = simplex.b;
-			simplex.b = a;
-			simplex.size = 2;
-			continue;
-		}
-		if ( simplex.size == 2 ) {
-			pod::Vector3 ao = a * -1;
-			pod::Vector3 ab = simplex.b - a;
-			pod::Vector3 ac = simplex.c - a;
-			pod::Vector3 abc = uf::vector::cross(ab, ac);
-			pod::Vector3 abP = uf::vector::cross(ab, abc);
-			if ( uf::vector::dot(abP, ao) > 0 ) {
-				simplex.c = simplex.b;
-				simplex.b = a;
-
-				direction = uf::vector::cross(ab, ao);
-				continue;
-			}
-			pod::Vector3 acP = uf::vector::cross(abc, ac);
-			if ( uf::vector::dot(acP, ao) > 0 ) {
-				simplex.b = a;
-
-				direction = uf::vector::cross(ac, ao);
-				continue;
-			}
-			if ( uf::vector::dot(abc, ao) > 0 ) {
-				simplex.d = simplex.c;
-				simplex.c = simplex.b;
-				simplex.b = a;
-
-				direction = abc;
-				continue;
-			}
-			simplex.d = simplex.b;
-			simplex.b = a;
-
-			direction = abc * -1;
-			simplex.size = 3;
-			continue;
-		}
-		if ( simplex.size == 3 ) {
-			pod::Vector3 ao = a * -1;
-			pod::Vector3 ab = simplex.b - a;
-			pod::Vector3 ac = simplex.c - a;
-			pod::Vector3 abc = uf::vector::cross(ab, ac);
-			pod::Vector3 ad, acd, adb;
-			if ( uf::vector::dot(abc, ao) > 0 ) {
-				goto check_face;
-			}
-			ad = simplex.d - a;
-			acd = uf::vector::cross(ac, ad);
-			if ( uf::vector::dot(acd, ao) > 0 ) {
-				simplex.b = simplex.c;
-				simplex.c = simplex.d;
-
-				ab = ac;
-				ac = ad;
-				abc = acd;
-
-				goto check_face;
-			}
-			goto EPA;
-
-		check_face:
-			pod::Vector3 abP = uf::vector::cross(ab, abc);
-			if ( uf::vector::dot(abP, ao) > 0 ) {
-				simplex.c = simplex.b;
-				simplex.b = a;
-
-				direction = uf::vector::cross(uf::vector::cross(ab, ao), ab);
-				simplex.size = 2;
-				continue;
-			}
-			pod::Vector3 acP = uf::vector::cross(abc, ac);
-			if ( uf::vector::dot(acP, ao) > 0 ) {
-				simplex.b = a;
-				direction = uf::vector::cross(uf::vector::cross(ac, ao), ac);
-				simplex.size = 2;
-				continue;
-			}
-			simplex.d = simplex.c;
-			simplex.c = simplex.b;
-			simplex.b = a;
-			direction = abc;
-			simplex.size = 3;
-			continue;
-		}
-	}
-	goto EPA;
-
-EPA:
-	manifold.colliding = true;
-	manifold.normal = direction;
-	manifold.depth = dot;
-	return manifold;
-}
-/*
-
-*/
-UF_API uf::AABBox::AABBox( const pod::Vector3& origin, const pod::Vector3& corner ) {
-	this->m_origin = origin;
-	this->m_corner = corner;
-}
-std::string UF_API uf::AABBox::type() const { return "AABBox"; }
-pod::Vector3* UF_API uf::AABBox::expand() const {
-	pod::Vector3* raw = new pod::Vector3[8];
-	raw[0] = pod::Vector3{  this->m_corner.x,  this->m_corner.y,  this->m_corner.z};
-	raw[1] = pod::Vector3{  this->m_corner.x,  this->m_corner.y, -this->m_corner.z};
-	raw[2] = pod::Vector3{ -this->m_corner.x,  this->m_corner.y, -this->m_corner.z};
-	raw[3] = pod::Vector3{ -this->m_corner.x,  this->m_corner.y,  this->m_corner.z};
-	raw[4] = pod::Vector3{ -this->m_corner.x, -this->m_corner.y,  this->m_corner.z};
-	raw[5] = pod::Vector3{  this->m_corner.x, -this->m_corner.y,  this->m_corner.z};
-	raw[6] = pod::Vector3{  this->m_corner.x, -this->m_corner.y, -this->m_corner.z};
-	raw[7] = pod::Vector3{ -this->m_corner.x, -this->m_corner.y,  this->m_corner.z};
-
-	for ( uint i = 0; i < 8; i++ ) raw[0] += this->m_origin;
-
-	return raw;
-}
-pod::Vector3 UF_API uf::AABBox::support( const pod::Vector3& direction ) const {
-	pod::Vector3 res;
-
-	res[0] = this->m_origin.x + this->m_corner.x * (direction.x >= 0 ? 1 : -1);
-	res[1] = this->m_origin.y + this->m_corner.y * (direction.y >= 0 ? 1 : -1);
-	res[2] = this->m_origin.z + this->m_corner.z * (direction.z >= 0 ? 1 : -1);
-
-	return res;
-}
-
-uf::Collider::Manifold UF_API uf::AABBox::intersects( const uf::AABBox& b ) const {
-	const uf::AABBox& a = *this;
-	uf::Collider::Manifold manifold(a, b);
-
-	float a_left 	= a.m_origin.x - a.m_corner.x;
-	float a_right 	= a.m_origin.x + a.m_corner.x;
-	float a_bottom 	= a.m_origin.y - a.m_corner.y;
-	float a_top 	= a.m_origin.y + a.m_corner.y;
-	float a_back 	= a.m_origin.z - a.m_corner.z;
-	float a_front 	= a.m_origin.z + a.m_corner.z;
-
-
-	float b_left 	= b.m_origin.x - b.m_corner.x;
-	float b_right 	= b.m_origin.x + b.m_corner.x;
-	float b_bottom 	= b.m_origin.y - b.m_corner.y;
-	float b_top 	= b.m_origin.y + b.m_corner.y;
-	float b_back 	= b.m_origin.z - b.m_corner.z;
-	float b_front 	= b.m_origin.z + b.m_corner.z;
-
-	manifold.depth = 9E9;
-	auto test = [&]( const pod::Vector3& axis, float minA, float maxA, float minB, float maxB )->bool{
-		float axisLSqr = uf::vector::dot(axis, axis);
-		if ( axisLSqr < 1E-8f ) return true;
-
-		float d0 = maxB - minA;
-		float d1 = maxA - minB;
-		if ( d0 < 0 || d1 < 0 ) return false;
-		float overlap = d0 < d1 ? d0 : -d1;
-		pod::Vector3 sep = axis * ( overlap / axisLSqr );
-		float sepLSqr = uf::vector::dot( sep, sep );
-		if ( sepLSqr < manifold.depth ) {
-			manifold.normal = sep;
-			manifold.depth = sepLSqr;
-		}
-		return true;
-	};
-
-	if ( !test( {1, 0, 0}, a_left, a_right, b_left, b_right ) ) return manifold;
-	if ( !test( {0, 1, 0}, a_bottom, a_top, b_bottom, b_top ) ) return manifold;
-	if ( !test( {0, 0, 1}, a_back, a_front, b_back, b_front ) ) return manifold;
-
-	manifold.normal = uf::vector::normalize( manifold.normal );
-	manifold.depth = sqrt( manifold.depth ); // * 1.001;
-	manifold.colliding = true;
-
-	return manifold;
-
-/*
-	if ( a_right < b_left ) return manifold;
-	if ( a_left > b_right ) return manifold;
-
-	if ( a_top < b_bottom ) return manifold;
-	if ( a_bottom > b_top ) return manifold;
-
-	if ( a_front < b_back ) return manifold;
-	if ( a_back > b_front ) return manifold;
-
-	pod::Vector3* a_points = a.expand();
-	pod::Vector3* b_points = b.expand();
-
-	float smallest = 9E9;
-	for ( uint b = 0; b < 8; b++ ) {
-	for ( uint a = 0; a < 8; a++ ) {
-		float distance = uf::vector::distanceSquared(b_points[b], a_points[a]);
-		smallest = fmin( smallest, distance );
-	}
-	}
-
-	delete[] a_points;
-	delete[] b_points;
-
-	manifold.depth = sqrt(smallest);
-	manifold.normal = b.m_origin - a.m_origin;
-	manifold.colliding = true;
-
-	return manifold;
-*/
-}
-/*
-
-*/
-UF_API uf::SphereCollider::SphereCollider( float r, const pod::Vector3& origin ) {
-	this->m_radius = r;
-	this->m_origin = origin;
-}
-std::string UF_API uf::SphereCollider::type() const { return "Sphere"; }
-float UF_API uf::SphereCollider::getRadius() const {
-	return this->m_radius;
-}
-const pod::Vector3& UF_API uf::SphereCollider::getOrigin() const {
-	return this->m_origin;
-}
-
-void UF_API uf::SphereCollider::setRadius( float r ) {
-	this->m_radius = r;
-}
-void UF_API uf::SphereCollider::setOrigin( const pod::Vector3& origin ) {
-	this->m_origin = origin;
-}
-
-pod::Vector3* UF_API uf::SphereCollider::expand() const {
-	return NULL;
-}
-pod::Vector3 UF_API uf::SphereCollider::support( const pod::Vector3& direction ) const {
-	return this->m_origin + direction * (this->m_radius/uf::vector::magnitude(direction));
-}
-uf::Collider::Manifold uf::SphereCollider::intersects( const uf::SphereCollider& b ) const {
-	const uf::SphereCollider& a = *this;
-	uf::Collider::Manifold manifold(a, b);
-	float distance = uf::vector::distance(a.m_origin, b.m_origin);
-	float sum = a.m_radius + b.m_radius;
-
-	if ( distance >= sum ) return manifold;
-
-	manifold.depth = fabs(b.m_radius - a.m_radius);
-	manifold.normal = b.m_origin - a.m_origin;
-	manifold.colliding = true;
-	return manifold;
-}
-/*
-
-*/
-/*
-uf::MeshCollider::MeshCollider( uf::Mesh& mesh ) : mesh(mesh) {
-	const uf::Mesh::vertices_t verts = this->m_mesh.getVertices();
-	this->m_raw = verts.get();
-}
-std::string UF_API uf::Collider::type() const { return "Mesh"; }
-uf::Mesh& uf::MeshCollider::getMesh() {
-	return this->m_mesh;
-}
-const uf::Mesh& uf::MeshCollider::getMesh() const {
-	return this->m_mesh;
-}
-void uf::MeshCollider::setMesh( const uf::Mesh& mesh ) {
-	this->m_mesh = mesh;
-	const uf::Mesh::vertices_t verts = this->m_mesh.getVertices();
-	this->m_raw = verts.get();
-}
-
-pod::Vector3* uf::MeshCollider::expand() const {
-	return (pod::Vector3*) &this->m_raw[0];
-}
-pod::Vector3 uf::MeshCollider::support( const pod::Vector3& direction ) const {
-	uint len = this->m_raw.size();
-	pod::Vector3* points = this->m_expand();
-	
-	uint best = 0;
-	float best_dot = points[0].dot(direction);
-
-	for ( uint i = 1; i < len; i++ ) {
-		float dot = points[i].dot(direction);
-		if ( dot > best_dot ) {
-			best = i;
-			best_dot = dot;
-		}
-	}
-	return points[best];
-}
-*/
-/*
-
-*/
-UF_API uf::ModularCollider::ModularCollider( uint len, pod::Vector3* container, bool should_free, const uf::ModularCollider::function_expand_t& expand, const uf::ModularCollider::function_support_t& support  ) {
-	this->m_len = len;
-	this->m_container = container;
-	this->m_should_free = should_free;
-	this->m_function_expand = expand;
-	this->m_function_support = support;
-}
-UF_API uf::ModularCollider::~ModularCollider() {
-	if ( this->m_container != NULL && this->m_should_free ) delete[] this->m_container;
-}
-std::string UF_API uf::ModularCollider::type() const { return "Modular"; }
-void UF_API uf::ModularCollider::setExpand( const uf::ModularCollider::function_expand_t& expand ) {
-	this->m_function_expand = expand;
-}
-void UF_API uf::ModularCollider::setSupport( const uf::ModularCollider::function_support_t& support ) {
-	this->m_function_support = support;
-}
-
-pod::Vector3* UF_API uf::ModularCollider::getContainer() {
-	return this->m_container;
-}
-uint UF_API uf::ModularCollider::getSize() const {
-	return this->m_len;
-}
-void UF_API uf::ModularCollider::setContainer( pod::Vector3* container, uint len ) {
-	this->m_container = container;
-	this->m_len = len;
-}
-
-pod::Vector3* UF_API uf::ModularCollider::expand() const {
-	return this->m_function_expand ? this->m_function_expand() : this->m_container;
-}
-pod::Vector3 UF_API uf::ModularCollider::support( const pod::Vector3& direction ) const {
-	if ( this->m_function_support ) return this->m_function_support(direction);
-	uint len = this->m_len;
-	pod::Vector3* points = this->expand();
-	
-	uint best = 0;
-	float best_dot = uf::vector::dot(points[0], direction);
-
-	for ( uint i = 1; i < len; i++ ) {
-		float dot = uf::vector::dot(points[i], direction);
-		if ( dot > best_dot ) {
-			best = i;
-			best_dot = dot;
-		}
-	}
-	return points[best];
-}
-
-uf::CollisionBody::~CollisionBody() {
+uf::Collider::~Collider() {
 	this->clear();
 }
-void UF_API uf::CollisionBody::clear() {
-	for ( uf::Collider* pointer : this->m_container ) delete pointer;
+void UF_API uf::Collider::clear() {
+	for ( pod::Collider* pointer : this->m_container ) delete pointer;
 	this->m_container.clear();
 }
 
-void UF_API uf::CollisionBody::add( uf::Collider* pointer ) {
+void UF_API uf::Collider::add( pod::Collider* pointer ) {
 	this->m_container.push_back(pointer);
 }
-uf::CollisionBody::container_t& UF_API uf::CollisionBody::getContainer() {
+uf::Collider::container_t& UF_API uf::Collider::getContainer() {
 	return this->m_container;
 }
-const uf::CollisionBody::container_t& UF_API uf::CollisionBody::getContainer() const {
+const uf::Collider::container_t& UF_API uf::Collider::getContainer() const {
 	return this->m_container;
 }
 
-std::size_t UF_API uf::CollisionBody::getSize() const {
+std::size_t UF_API uf::Collider::getSize() const {
 	return this->m_container.size();
 }
 
-std::vector<uf::Collider::Manifold> UF_API uf::CollisionBody::intersects( const uf::CollisionBody& body ) const {
-	std::vector<uf::Collider::Manifold> manifolds;
-	for ( const uf::Collider* pointer : body.m_container ) {
-		std::vector<uf::Collider::Manifold> result = this->intersects( *pointer );
+std::vector<pod::Collider::Manifold> UF_API uf::Collider::intersects( const uf::Collider& body, bool smart ) const {
+	std::vector<pod::Collider::Manifold> manifolds;
+	manifolds.reserve( this->m_container.size() * body.m_container.size() );
+	for ( const pod::Collider* pointer : body.m_container ) {
+		std::vector<pod::Collider::Manifold> result = this->intersects( *pointer, smart );
 		manifolds.insert( manifolds.end(), result.begin(), result.end() );
 	}
 	return manifolds;
 }
 
-std::vector<uf::Collider::Manifold> UF_API uf::CollisionBody::intersects( const uf::Collider& body ) const {
-	std::vector<uf::Collider::Manifold> manifolds;
-	for ( const uf::Collider* pointer : this->m_container ) {
-		uf::Collider::Manifold manifold;
+std::vector<pod::Collider::Manifold> UF_API uf::Collider::intersects( const pod::Collider& body, bool smart ) const {
+	// smart = false;
+	std::vector<pod::Collider::Manifold> manifolds;
+	for ( const pod::Collider* pointer : this->m_container ) {
+		pod::Collider::Manifold& manifold = manifolds.emplace_back();
 		if ( !pointer ) continue;
-		if ( pointer->type() == body.type() ) {
-			if ( pointer->type() == "AABBox" ) {
-				const uf::AABBox& a = *((const uf::AABBox*) pointer);
-				const uf::AABBox& b = *((const uf::AABBox*) &body);
+		if ( smart && pointer->type() == body.type() ) {
+			if ( pointer->type() == "BoundingBox" ) {
+				const uf::BoundingBox& a = *((const uf::BoundingBox*) pointer);
+				const uf::BoundingBox& b = *((const uf::BoundingBox*) &body);
 				manifold = a.intersects(b);
 			} else if ( pointer->type() == "Sphere" ) {
 				const uf::SphereCollider& a = *((const uf::SphereCollider*) pointer);
 				const uf::SphereCollider& b = *((const uf::SphereCollider*) &body);
 				manifold = a.intersects(b);
 			}
-			else manifold = pointer->intersects( body );
+			else
+				manifold = pointer->intersects( body );
 		} else manifold = pointer->intersects( body );
-		manifolds.push_back( manifold );		
 	}
 	return manifolds;
 }
\ No newline at end of file
diff --git a/engine/src/utils/math/collision/boundingbox.cpp b/engine/src/utils/math/collision/boundingbox.cpp
new file mode 100644
index 00000000..36bd562e
--- /dev/null
+++ b/engine/src/utils/math/collision/boundingbox.cpp
@@ -0,0 +1,157 @@
+#include <uf/utils/math/collision/boundingbox.h>
+
+UF_API uf::BoundingBox::BoundingBox( const pod::Vector3& origin, const pod::Vector3& corner ) {
+	this->m_origin = origin;
+	this->m_corner = corner;
+}
+const pod::Vector3& uf::BoundingBox::getOrigin() const {
+	return this->m_origin;
+}
+const pod::Vector3& uf::BoundingBox::getCorner() const {
+	return this->m_corner;
+}
+void uf::BoundingBox::setOrigin( const pod::Vector3& origin ) {
+	this->m_origin = origin;
+}
+void uf::BoundingBox::setCorner( const pod::Vector3& corner ) {
+	this->m_corner = corner;
+}
+pod::Vector3 uf::BoundingBox::min() const {
+	pod::Vector3f position = this->getPosition() + this->m_origin;
+	// const pod::Vector3f& position = this->m_origin;
+	return position - this->m_corner;
+}
+pod::Vector3 uf::BoundingBox::max() const {
+	pod::Vector3f position = this->getPosition() + this->m_origin;
+	// const pod::Vector3f& position = this->m_origin;
+	return position + this->m_corner;
+}
+pod::Vector3 uf::BoundingBox::closest( const pod::Vector3f& point ) const {
+	pod::Vector3f position = this->getPosition() + this->m_origin;
+	// const pod::Vector3f& position = this->m_origin;
+
+	float distance = 9E9;
+	pod::Vector3f vector = point;
+	pod::Vector3f min = position - this->m_corner;
+	pod::Vector3f max = position + this->m_corner;
+
+	float test = 0;
+	if ( (test = fabs(min.x - point.x)) < distance ) {
+		distance = test;
+		vector.x = min.x;
+	}
+	if ( (test = fabs(max.x - point.x)) < distance ) {
+		distance = test;
+		vector.x = max.x;
+	}
+
+	if ( (test = fabs(min.y - point.y)) < distance ) {
+		distance = test;
+		vector.y = min.y;
+	}
+	if ( (test = fabs(max.y - point.y)) < distance ) {
+		distance = test;
+		vector.y = max.y;
+	}
+
+	if ( (test = fabs(min.z - point.z)) < distance ) {
+		distance = test;
+		vector.z = min.z;
+	}
+	if ( (test = fabs(max.z - point.z)) < distance ) {
+		distance = test;
+		vector.z = max.z;
+	}
+
+	return vector;
+}
+std::string UF_API uf::BoundingBox::type() const { return "BoundingBox"; }
+pod::Vector3* UF_API uf::BoundingBox::expand() const {
+	pod::Vector3* raw = new pod::Vector3[8];
+	raw[0] = pod::Vector3{  this->m_corner.x,  this->m_corner.y,  this->m_corner.z};
+	raw[1] = pod::Vector3{  this->m_corner.x,  this->m_corner.y, -this->m_corner.z};
+	raw[2] = pod::Vector3{ -this->m_corner.x,  this->m_corner.y, -this->m_corner.z};
+	raw[3] = pod::Vector3{ -this->m_corner.x,  this->m_corner.y,  this->m_corner.z};
+	raw[4] = pod::Vector3{ -this->m_corner.x, -this->m_corner.y,  this->m_corner.z};
+	raw[5] = pod::Vector3{  this->m_corner.x, -this->m_corner.y,  this->m_corner.z};
+	raw[6] = pod::Vector3{  this->m_corner.x, -this->m_corner.y, -this->m_corner.z};
+	raw[7] = pod::Vector3{ -this->m_corner.x, -this->m_corner.y,  this->m_corner.z};
+
+	pod::Vector3f position = this->getPosition() + this->m_origin;
+	// const pod::Vector3f& position = this->m_origin;
+	for ( uint i = 0; i < 8; i++ ) raw[0] += position;
+
+	return raw;
+}
+pod::Vector3 UF_API uf::BoundingBox::support( const pod::Vector3& direction ) const {
+	pod::Vector3f position = this->getPosition() + this->m_origin;
+	// const pod::Vector3f& position = this->m_origin;
+	pod::Vector3 res = {
+		position.x + fabs(this->m_corner.x) * (direction.x > 0 ? 1 : -1),
+		position.y + fabs(this->m_corner.y) * (direction.y > 0 ? 1 : -1),
+		position.z + fabs(this->m_corner.z) * (direction.z > 0 ? 1 : -1),
+	};
+	return res;
+}
+
+pod::Collider::Manifold UF_API uf::BoundingBox::intersects( const uf::BoundingBox& b ) const {
+	const uf::BoundingBox& a = *this;
+	pod::Collider::Manifold manifold(a, b);
+
+	BoundingBox difference(a.min() - b.max() + a.m_corner + b.m_corner, (a.m_corner + b.m_corner) * 2.0f);
+
+	pod::Vector3f min = difference.m_origin - this->m_corner;
+	pod::Vector3f max = difference.m_origin + this->m_corner;
+	manifold.colliding = min.x <= 0 && max.x >= 0 && min.y <= 0 && max.y >= 0;
+
+	if ( !manifold.colliding ) return manifold;
+
+	pod::Vector3f penetration = difference.closest( {0, 0, 0} );
+	manifold.depth = uf::vector::norm( penetration );
+	manifold.normal = penetration / manifold.depth;
+
+/*
+	float a_left 	= position_a.x - a.m_corner.x;
+	float a_right 	= position_a.x + a.m_corner.x;
+	float a_bottom 	= position_a.y - a.m_corner.y;
+	float a_top 	= position_a.y + a.m_corner.y;
+	float a_back 	= position_a.z - a.m_corner.z;
+	float a_front 	= position_a.z + a.m_corner.z;
+
+
+	float b_left 	= position_b.x - b.m_corner.x;
+	float b_right 	= position_b.x + b.m_corner.x;
+	float b_bottom 	= position_b.y - b.m_corner.y;
+	float b_top 	= position_b.y + b.m_corner.y;
+	float b_back 	= position_b.z - b.m_corner.z;
+	float b_front 	= position_b.z + b.m_corner.z;
+
+	manifold.depth = 9E9;
+	auto test = [&]( const pod::Vector3& axis, float minA, float maxA, float minB, float maxB )->bool{
+		float axisLSqr = uf::vector::dot(axis, axis);
+		if ( axisLSqr < 1E-8f ) return true;
+
+		float d0 = maxB - minA;
+		float d1 = maxA - minB;
+		if ( d0 < 0 || d1 < 0 ) return false;
+		float overlap = d0 < d1 ? d0 : -d1;
+		pod::Vector3 sep = axis * ( overlap / axisLSqr );
+		float sepLSqr = uf::vector::dot( sep, sep );
+		if ( sepLSqr < manifold.depth ) {
+			manifold.normal = sep;
+			manifold.depth = sepLSqr;
+		}
+		return true;
+	};
+
+	if ( !test( {1, 0, 0}, a_left, a_right, b_left, b_right ) ) return manifold;
+	if ( !test( {0, 1, 0}, a_bottom, a_top, b_bottom, b_top ) ) return manifold;
+	if ( !test( {0, 0, 1}, a_back, a_front, b_back, b_front ) ) return manifold;
+
+	manifold.normal = uf::vector::normalize( manifold.normal );
+	manifold.depth = sqrt( manifold.depth );
+//	manifold.depth = manifold.depth;
+	manifold.colliding = true;
+*/
+	return manifold;
+}
\ No newline at end of file
diff --git a/engine/src/utils/math/collision/gjk.cpp b/engine/src/utils/math/collision/gjk.cpp
new file mode 100644
index 00000000..17015b3e
--- /dev/null
+++ b/engine/src/utils/math/collision/gjk.cpp
@@ -0,0 +1,247 @@
+#include <uf/utils/math/collision/gjk.h>
+
+/*
+pod::Simplex::Simplex( const pod::Vector3& b, const pod::Vector3& c, const pod::Vector3& d ) {
+	this->set(b, c, d);
+}
+void pod::Simplex::add( const pod::Vector3& a ) {
+	this->d = this->c;
+	this->c = this->b;
+	this->b = a;
+}
+void pod::Simplex::set( const pod::Vector3& b, const pod::Vector3& c, const pod::Vector3& d ) {
+	this->b = b;
+	this->c = c;
+	this->d = d;
+	if ( b != pod::Vector3{} ) this->size++;
+	if ( c != pod::Vector3{} ) this->size++;
+	if ( d != pod::Vector3{} ) this->size++;
+}
+*/
+pod::Collider::~Collider(){}
+std::string UF_API pod::Collider::type() const { return ""; }
+pod::Collider::Manifold UF_API pod::Collider::intersects( const pod::Collider& y ) const {
+	const pod::Collider& x = *this;
+	
+	pod::Simplex::SupportPoint a;
+	pod::Simplex simplex;
+	pod::Vector3 direction = pod::Vector3{ 1.0f, 0.0f, 0.0f };
+	
+	pod::Collider::Manifold manifold(x, y);
+	float dot = -0.1;
+	uint16_t iterations = 0;
+	uint16_t iterations_cap = 25;
+	while ( iterations++ < iterations_cap ) {
+		direction = uf::vector::normalize(direction);
+
+		a = pod::Simplex::SupportPoint{};
+		a.a = x.support(direction);
+		a.b = y.support(-direction);
+		a.v = a.a - a.b;
+
+		if ( (dot = a.dot(direction)) < 0 ) {
+			return manifold;
+		}
+		if( simplex.size == 0 ) {	
+			simplex.b = a;
+
+			direction = direction * -1;
+			simplex.size = 1;
+			continue;
+		}
+		if ( simplex.size == 1 ) {
+			direction = uf::vector::cross(a.cross(simplex.b), a.v);
+			simplex.c = simplex.b;
+			simplex.b = a;
+			simplex.size = 2;
+			continue;
+		}
+		if ( simplex.size == 2 ) {
+			pod::Vector3 ao = a * -1;
+			pod::Vector3 ab = simplex.b - a;
+			pod::Vector3 ac = simplex.c - a;
+			pod::Vector3 abc = uf::vector::cross(ab, ac);
+			pod::Vector3 abP = uf::vector::cross(ab, abc);
+			if ( uf::vector::dot(abP, ao) > 0 ) {
+				simplex.c = simplex.b;
+				simplex.b = a;
+
+				direction = uf::vector::cross(ab, ao);
+				continue;
+			}
+			pod::Vector3 acP = uf::vector::cross(abc, ac);
+			if ( uf::vector::dot(acP, ao) > 0 ) {
+				simplex.b = a;
+
+				direction = uf::vector::cross(ac, ao);
+				continue;
+			}
+			if ( uf::vector::dot(abc, ao) > 0 ) {
+				simplex.d = simplex.c;
+				simplex.c = simplex.b;
+				simplex.b = a;
+
+				direction = abc;
+				continue;
+			}
+			simplex.d = simplex.b;
+			simplex.b = a;
+
+			direction = abc * -1;
+			simplex.size = 3;
+			continue;
+		}
+		if ( simplex.size == 3 ) {
+			pod::Vector3 ao = a * -1;
+			pod::Vector3 ab = simplex.b - a;
+			pod::Vector3 ac = simplex.c - a;
+			pod::Vector3 abc = uf::vector::cross(ab, ac);
+			pod::Vector3 ad, acd, adb;
+			if ( uf::vector::dot(abc, ao) > 0 ) {
+				goto check_face;
+			}
+			ad = simplex.d - a;
+			acd = uf::vector::cross(ac, ad);
+			if ( uf::vector::dot(acd, ao) > 0 ) {
+				simplex.b = simplex.c;
+				simplex.c = simplex.d;
+
+				ab = ac;
+				ac = ad;
+				abc = acd;
+
+				goto check_face;
+			}
+			goto EPA;
+
+		check_face:
+			pod::Vector3 abP = uf::vector::cross(ab, abc);
+			if ( uf::vector::dot(abP, ao) > 0 ) {
+				simplex.c = simplex.b;
+				simplex.b = a;
+
+				direction = uf::vector::cross(uf::vector::cross(ab, ao), ab);
+				simplex.size = 2;
+				continue;
+			}
+			pod::Vector3 acP = uf::vector::cross(abc, ac);
+			if ( uf::vector::dot(acP, ao) > 0 ) {
+				simplex.b = a;
+				direction = uf::vector::cross(uf::vector::cross(ac, ao), ac);
+				simplex.size = 2;
+				continue;
+			}
+			simplex.d = simplex.c;
+			simplex.c = simplex.b;
+			simplex.b = a;
+			direction = abc;
+			simplex.size = 3;
+			continue;
+		}
+	}
+	return manifold;
+
+EPA:
+	struct Triangle {
+		pod::Simplex::SupportPoint points[3];
+		pod::Vector3f normal;
+		Triangle( const pod::Simplex::SupportPoint& a, const pod::Simplex::SupportPoint& b, const pod::Simplex::SupportPoint& c ) {
+			points[0] = a;
+			points[1] = b;
+			points[2] = c;
+			normal = uf::vector::normalize( uf::vector::cross( b.v - a.v, c.v - a.v ) );
+		}
+	};
+	struct Edge {
+		pod::Simplex::SupportPoint points[2];
+		Edge( const pod::Simplex::SupportPoint& a, const pod::Simplex::SupportPoint& b ) {
+			points[0] = a;
+			points[1] = b;
+		}
+	};
+
+	iterations = 0;
+	manifold.colliding = true;
+	manifold.depth = 0.0f;
+	manifold.normal = { 0, 0, 0 };
+
+	std::vector<Triangle> triangles;
+	std::vector<Edge> edges;
+
+	triangles.emplace_back(         a, simplex.b, simplex.c );
+	triangles.emplace_back(         a, simplex.b, simplex.d );
+	triangles.emplace_back(         a, simplex.c, simplex.d );
+	triangles.emplace_back( simplex.b, simplex.c, simplex.d );
+
+	auto addEdge = [&]( const pod::Simplex::SupportPoint& a, const pod::Simplex::SupportPoint& b ) {
+		for ( auto it = edges.begin(); it != edges.end(); ++it ) {
+			if( it->points[0]== b && it->points[1]== a ) {
+				edges.erase(it);
+				return;
+			}
+		}
+		edges.emplace_back( a, b );
+	};
+
+	while ( iterations++ < iterations_cap ) {
+		// find closest triangle to origin
+		struct {
+			std::vector<Triangle>::iterator it;
+			float distance = 9E9;
+			pod::Simplex::SupportPoint support;
+		} closest = { triangles.begin() };
+
+		for(auto it = triangles.begin(); it != triangles.end(); it++) {
+			float distance = fabs( uf::vector::dot(it->normal, it->points[0].v) );
+			if( distance < closest.distance ) {
+				closest.distance = distance;
+				closest.it = it;
+			}
+		}
+		{
+			closest.support.a = x.support(closest.it->normal);
+			closest.support.b = y.support(-closest.it->normal);
+			closest.support.v = closest.support.a - closest.support.b;
+		}
+
+		manifold.normal = -closest.it->normal;
+		manifold.depth = uf::vector::dot( closest.it->normal, closest.support.v );
+		if( manifold.depth - closest.distance < 0.00001f ) {
+			manifold.depth = uf::vector::dot( closest.it->normal, closest.it->points[0].v );
+			return manifold;
+		}
+
+		for(auto it = triangles.begin(); it != triangles.end();) {
+			// can this face be 'seen' by closest.support?
+			if( uf::vector::dot( it->normal, (closest.support.v - it->points[0].v) ) > 0) {
+				addEdge( it->points[0], it->points[1] );
+				addEdge( it->points[1], it->points[2] );
+				addEdge( it->points[2], it->points[0] );
+				it = triangles.erase(it);
+				continue;
+			}
+			it++;
+		}
+
+		// create new triangles from the edges in the edge list
+		for(auto it = edges.begin(); it != edges.end(); it++)
+			triangles.emplace_back( closest.support, it->points[0], it->points[1] );
+
+		edges.clear();
+	}
+	return manifold;
+}
+
+pod::Vector3f pod::Collider::getPosition() const {
+	return this->m_transform.reference ? this->m_transform.reference->position : this->m_transform.position;
+//	return uf::transform::flatten( this->m_transform.reference ? *this->m_transform.reference : this->m_transform ).position;
+}
+pod::Transform<>& pod::Collider::getTransform() {
+	return this->m_transform;
+}
+const pod::Transform<>& pod::Collider::getTransform() const {
+	return this->m_transform;
+}
+void pod::Collider::setTransform( const pod::Transform<>& transform ) {
+	this->m_transform = transform;
+}
\ No newline at end of file
diff --git a/engine/src/utils/math/collision/mesh.cpp b/engine/src/utils/math/collision/mesh.cpp
new file mode 100644
index 00000000..e165f9a1
--- /dev/null
+++ b/engine/src/utils/math/collision/mesh.cpp
@@ -0,0 +1,42 @@
+#include <uf/utils/math/collision/mesh.h>
+
+uf::MeshCollider::MeshCollider( const pod::Transform<>& transform, const std::vector<pod::Vector3>& positions ) : m_positions(positions) {
+	this->setTransform(transform);
+}
+std::string UF_API uf::MeshCollider::type() const { return "Mesh"; }
+
+std::vector<pod::Vector3>& uf::MeshCollider::getPositions() {
+	return this->m_positions;
+}
+
+const std::vector<pod::Vector3>& uf::MeshCollider::getPositions() const {
+	return this->m_positions;
+}
+
+void uf::MeshCollider::setPositions( const std::vector<pod::Vector3>& positions ) {
+	this->m_positions = positions;
+}
+
+pod::Vector3* uf::MeshCollider::expand() const {
+	return (pod::Vector3*) &this->m_positions[0];
+}
+pod::Vector3 uf::MeshCollider::support( const pod::Vector3& direction ) const {
+	size_t len = this->m_positions.size();
+	pod::Vector3* points = this->expand();
+	pod::Matrix4f model = uf::transform::model( this->m_transform );
+
+	struct {
+		size_t i = 0;
+		float dot = 0;
+	} best;
+
+	for ( size_t i = 0; i < len; ++i ) {
+		float dot = uf::vector::dot( uf::matrix::multiply<float>( model, points[i] ), direction);
+	//	float dot = uf::vector::dot( points[i], direction);
+		if ( i == 0 || dot > best.dot ) {
+			best.i = i;
+			best.dot = dot;
+		}
+	}
+	return points[best.i];
+}
\ No newline at end of file
diff --git a/engine/src/utils/math/collision/modular.cpp b/engine/src/utils/math/collision/modular.cpp
new file mode 100644
index 00000000..97b39242
--- /dev/null
+++ b/engine/src/utils/math/collision/modular.cpp
@@ -0,0 +1,55 @@
+#include <uf/utils/math/collision/modular.h>
+
+UF_API uf::ModularCollider::ModularCollider( uint len, pod::Vector3* container, bool should_free, const uf::ModularCollider::function_expand_t& expand, const uf::ModularCollider::function_support_t& support  ) {
+	this->m_len = len;
+	this->m_container = container;
+	this->m_should_free = should_free;
+	this->m_function_expand = expand;
+	this->m_function_support = support;
+}
+UF_API uf::ModularCollider::~ModularCollider() {
+	if ( this->m_container != NULL && this->m_should_free ) delete[] this->m_container;
+}
+std::string UF_API uf::ModularCollider::type() const { return "Modular"; }
+void UF_API uf::ModularCollider::setExpand( const uf::ModularCollider::function_expand_t& expand ) {
+	this->m_function_expand = expand;
+}
+void UF_API uf::ModularCollider::setSupport( const uf::ModularCollider::function_support_t& support ) {
+	this->m_function_support = support;
+}
+
+pod::Vector3* UF_API uf::ModularCollider::getContainer() {
+	return this->m_container;
+}
+uint UF_API uf::ModularCollider::getSize() const {
+	return this->m_len;
+}
+void UF_API uf::ModularCollider::setContainer( pod::Vector3* container, uint len ) {
+	this->m_container = container;
+	this->m_len = len;
+}
+
+pod::Vector3* UF_API uf::ModularCollider::expand() const {
+	return this->m_function_expand ? this->m_function_expand() : this->m_container;
+}
+pod::Vector3 UF_API uf::ModularCollider::support( const pod::Vector3& direction ) const {
+	if ( this->m_function_support ) return this->m_function_support(direction);
+	
+	pod::Vector3* points = this->expand();
+	uint len = this->m_len;
+	
+	struct {
+		size_t i = 0;
+		float dot = 0;
+	} best;
+
+	for ( size_t i = 0; i < len; ++i ) {
+	//	float dot = uf::vector::dot( uf::matrix::multiply<float>( model, points[i] ), direction);
+		float dot = uf::vector::dot( points[i], direction);
+		if ( i == 0 || dot > best.dot ) {
+			best.i = i;
+			best.dot = dot;
+		}
+	}
+	return points[best.i];
+}
\ No newline at end of file
diff --git a/engine/src/utils/math/collision/sphere.cpp b/engine/src/utils/math/collision/sphere.cpp
new file mode 100644
index 00000000..5501458c
--- /dev/null
+++ b/engine/src/utils/math/collision/sphere.cpp
@@ -0,0 +1,49 @@
+#include <uf/utils/math/collision/sphere.h>
+
+UF_API uf::SphereCollider::SphereCollider( float r, const pod::Vector3& origin ) {
+	this->m_radius = r;
+	this->m_origin = origin;
+}
+std::string UF_API uf::SphereCollider::type() const { return "Sphere"; }
+float UF_API uf::SphereCollider::getRadius() const {
+	return this->m_radius;
+}
+const pod::Vector3& UF_API uf::SphereCollider::getOrigin() const {
+	return this->m_origin;
+}
+
+void UF_API uf::SphereCollider::setRadius( float r ) {
+	this->m_radius = r;
+}
+void UF_API uf::SphereCollider::setOrigin( const pod::Vector3& origin ) {
+	this->m_origin = origin;
+}
+
+pod::Vector3* UF_API uf::SphereCollider::expand() const {
+	return NULL;
+}
+pod::Vector3 UF_API uf::SphereCollider::support( const pod::Vector3& direction ) const {
+	pod::Vector3f position = this->getPosition() + this->m_origin;
+//	const pod::Vector3f& position = this->m_origin;
+	return position + direction * (this->m_radius/uf::vector::magnitude(direction));
+}
+pod::Collider::Manifold uf::SphereCollider::intersects( const uf::SphereCollider& b ) const {
+	const uf::SphereCollider& a = *this;
+	pod::Collider::Manifold manifold(a, b);
+
+	pod::Vector3f position_a = a.getPosition() + a.m_origin;
+	pod::Vector3f position_b = b.getPosition() + b.m_origin;
+	// const pod::Vector3f& position_a = a.m_origin;
+	// const pod::Vector3f& position_b = b.m_origin;
+
+	float distanceSquared = uf::vector::distanceSquared(position_a, position_b);
+	float sum = a.m_radius + b.m_radius;
+	float sumSquared = sum * sum;
+
+	if ( distanceSquared >= sumSquared ) return manifold;
+
+	manifold.depth = fabs(b.m_radius - a.m_radius);
+	manifold.normal = position_b - position_a;
+	manifold.colliding = true;
+	return manifold;
+}
\ No newline at end of file
diff --git a/engine/src/utils/math/physics.cpp b/engine/src/utils/math/physics.cpp
index 646a4ed9..fe6e42dd 100644
--- a/engine/src/utils/math/physics.cpp
+++ b/engine/src/utils/math/physics.cpp
@@ -1,5 +1,11 @@
 #include <uf/utils/math/physics.h>
 
+uf::Timer<> uf::physics::time::timer;
+double uf::physics::time::current;
+double uf::physics::time::previous;
+double uf::physics::time::delta;
+double uf::physics::time::clamp;
+
 void UF_API uf::physics::tick() {
 	uf::physics::time::previous = uf::physics::time::current;
 	uf::physics::time::current = uf::physics::time::timer.elapsed().asDouble();
diff --git a/ext/gui/gui.cpp b/ext/gui/gui.cpp
index bfb20045..f48f0d8e 100644
--- a/ext/gui/gui.cpp
+++ b/ext/gui/gui.cpp
@@ -745,7 +745,7 @@ void ext::Gui::initialize() {
 		float delay = 0.0f;
 		float scale = metadata["text settings"]["scale"].asFloat();
 		std::vector<::GlyphBox> glyphs = generateGlyphs(*this);
-		std::cout << "Loading string: " << metadata["text settings"]["string"] << std::endl;
+	//	std::cout << "Loading string: " << metadata["text settings"]["string"] << std::endl;
 		for ( auto& glyph : glyphs ) {
 			ext::Gui* glyphElement = (ext::Gui*) this->findByUid( this->loadChild("/gui/text/letter.json", false) );
 		/*
@@ -860,7 +860,7 @@ void ext::Gui::render() {
 				metadata["text settings"]["stroke"][2].asFloat(),
 				metadata["text settings"]["stroke"][3].asFloat()
 			};
-
+		/*
 			if ( uf::Window::isKeyPressed("V") ) {
 				metadata["text settings"]["weight"] = metadata["text settings"]["weight"].asFloat() + uf::physics::time::delta;
 				std::cout << metadata["text settings"]["weight"].asFloat() << std::endl;
@@ -877,7 +877,7 @@ void ext::Gui::render() {
 				metadata["text settings"]["spread"] = metadata["text settings"]["spread"].asFloat() - uf::physics::time::delta;
 				std::cout << metadata["text settings"]["spread"].asFloat() << std::endl;
 			}
-
+		*/
 			uniforms.gui.offset = offset;
 			uniforms.gui.color = color;
 			uniforms.gui.stroke = stroke;
@@ -1036,7 +1036,7 @@ void ext::Gui::render() {
 						alignas(8) pod::Vector2f radius = { 0.1f, 0.1f };
 						alignas(16) pod::Vector4f color = { 1, 1, 1, 1 };
 					} cursor;
-					alignas(4) float alpha;
+					alignas(8) pod::Vector2f alpha;
 				};
 				auto& shader = blitter.material.shaders.front();
 				auto& uniforms = shader.uniforms.front().get<UniformDescriptor>();
@@ -1077,7 +1077,8 @@ void ext::Gui::render() {
 						pod::Matrix4t<> model = uf::matrix::translate( uf::matrix::identity(), { 0, 0, 1 } );
 						uniforms.matrices.models[i] = model;
 					}
-					uniforms.alpha = metadata["overlay"]["alpha"].asFloat();
+					uniforms.alpha.x = metadata["overlay"]["alpha"].asFloat();
+					uniforms.alpha.y = 0;
 
 					uniforms.cursor.position.x = (metadata["overlay"]["cursor"]["position"][0].asFloat() + 1.0f) * 0.5f; //(::mouse.position.x + 1.0f) * 0.5f;
 					uniforms.cursor.position.y = (metadata["overlay"]["cursor"]["position"][1].asFloat() + 1.0f) * 0.5f; //(::mouse.position.y + 1.0f) * 0.5f;
diff --git a/ext/main.cpp b/ext/main.cpp
index 680a220a..11ef47b4 100644
--- a/ext/main.cpp
+++ b/ext/main.cpp
@@ -102,12 +102,22 @@ void EXT_API ext::initialize() {
 		// Set worker threads
 		uf::thread::workers = ::config["engine"]["worker threads"].asUInt64();
 		// Enable valiation layer
-		ext::vulkan::validation = ::config["engine"]["ext"]["vulkan"]["validation"].asBool();
+		ext::vulkan::validation = ::config["engine"]["ext"]["vulkan"]["validation"]["enabled"].asBool();
+
+		for ( int i = 0; i < ::config["engine"]["ext"]["vulkan"]["validation"]["filters"].size(); ++i ) {
+			ext::vulkan::validationFilters.push_back( ::config["engine"]["ext"]["vulkan"]["validation"]["filters"][i].asString() );
+		}
+		for ( int i = 0; i < ::config["engine"]["ext"]["vulkan"]["features"].size(); ++i ) {
+			ext::vulkan::requestedDeviceFeatures.push_back( ::config["engine"]["ext"]["vulkan"]["features"][i].asString() );
+		}
 		//
 		// ext::vulkan::DeferredRenderingGraphic::maxLights = ::config["engine"]["scenes"]["max lights"].asUInt();
 		//
 		ext::openvr::enabled = ::config["engine"]["ext"]["vr"]["enable"].asBool();
 		ext::openvr::swapEyes = ::config["engine"]["ext"]["vr"]["swap eyes"].asBool();
+	//	ext::openvr::dominantEye = ::config["engine"]["ext"]["vr"]["dominatEye"].asString() == "left" ? 0 : 1;
+		if ( ::config["engine"]["ext"]["vr"]["dominatEye"].asString() == "left" ) ext::openvr::dominantEye = 0;
+		if ( ::config["engine"]["ext"]["vr"]["dominatEye"].asString() == "right" ) ext::openvr::dominantEye = 1;
 		ext::openvr::driver.manifest = ::config["engine"]["ext"]["vr"]["manifest"].asString();
 		if ( ext::openvr::enabled ) {
 			::config["engine"]["render modes"]["stereo deferred"] = true;
@@ -222,13 +232,42 @@ void EXT_API ext::tick() {
 	    	uf::iostream << ext::vulkan::allocatorStats() << "\n";
 		}
 	}
-	/* Print Entity Information */  {
+	/* Attempt to reset VR position */  {
 		static uf::Timer<long long> timer(false);
 		if ( !timer.running() ) timer.start();
-		if ( uf::Window::isKeyPressed("Home") && timer.elapsed().asDouble() >= 1 ) { timer.reset();
+		if ( uf::Window::isKeyPressed("Z") && timer.elapsed().asDouble() >= 1 ) { timer.reset();
 	    	uf::hooks.call("VR:Seat.Reset");
 		}
 	}
+	/* Print controller position */ if ( false ) {
+		static uf::Timer<long long> timer(false);
+		if ( !timer.running() ) timer.start();
+		if ( uf::Window::isKeyPressed("Z") && timer.elapsed().asDouble() >= 1 ) { timer.reset();
+			auto& scene = uf::scene::getCurrentScene();
+			auto* controller = scene.getController();
+			auto& camera = controller->getComponent<uf::Camera>();
+			auto& t = camera.getTransform(); //controller->getComponent<pod::Transform<>>();
+			uf::iostream << "Viewport position: (" << t.position.x << ", " << t.position.y << ", " << t.position.z << ") (" << t.orientation.x << ", " << t.orientation.y << ", " << t.orientation.z << ", " << t.orientation.w << ")";
+			uf::iostream << "\n";
+			if ( false ) {
+				uf::Entity* light = scene.findByUid(scene.loadChild("/light.json", true));
+				if ( light ) {
+					auto& lTransform = light->getComponent<pod::Transform<>>();
+					auto& lMetadata = light->getComponent<uf::Serializer>();
+					lTransform.position = t.position;
+					lTransform.orientation = t.orientation;
+					if ( !lMetadata["light"].isArray() ) {
+						lMetadata["light"]["color"][0] = (rand() % 100) / 100.0;
+						lMetadata["light"]["color"][1] = (rand() % 100) / 100.0;
+						lMetadata["light"]["color"][2] = (rand() % 100) / 100.0;
+					}
+				}
+				
+				auto& sMetadata = scene.getComponent<uf::Serializer>();
+				sMetadata["light"]["should"] = true;
+			}
+		}
+	}
 
 	/* Update physics timer */ {
 		uf::physics::tick();
diff --git a/ext/scenes/test/scene.cpp b/ext/scenes/test/scene.cpp
index 6da0d247..046b109c 100644
--- a/ext/scenes/test/scene.cpp
+++ b/ext/scenes/test/scene.cpp
@@ -7,11 +7,18 @@
 
 #include <uf/utils/audio/audio.h>
 #include <uf/utils/thread/thread.h>
+#include <uf/utils/camera/camera.h>
 
 #include <uf/engine/asset/asset.h>
 #include <uf/engine/asset/masterdata.h>
 
 #include <uf/ext/vulkan/vulkan.h>
+#include <uf/ext/vulkan/rendermodes/deferred.h>
+#include <uf/ext/vulkan/rendermodes/rendertarget.h>
+#include <uf/ext/vulkan/rendermodes/stereoscopic_deferred.h>
+#include <uf/ext/gltf/gltf.h>
+
+#include <uf/utils/math/collision.h>
 
 #include "../../ext.h"
 #include "../../gui/gui.h"
@@ -27,34 +34,6 @@ void ext::TestScene::initialize() {
 		ext::ready = false;
 		return "true";
 	});
-	this->addHook( "asset:Load." + std::to_string(this->getUid()), [&](const std::string& event)->std::string{	
-		uf::Serializer json = event;
-		std::string filename = json["filename"].asString();
-
-		if ( uf::string::extension(filename) != "ogg" ) return "false";
-		const uf::Audio* audioPointer = NULL;
-		try { audioPointer = &assetLoader.get<uf::Audio>(filename); } catch ( ... ) {}
-		if ( !audioPointer ) return "false";
-
-		uf::Audio& audio = this->getComponent<uf::Audio>();
-		if ( audio.playing() ) {
-		/*
-			if ( filename.find("_intro") == std::string::npos ) {
-				metadata["previous bgm"]["filename"] = audio.getFilename();
-				metadata["previous bgm"]["timestamp"] = audio.getTime();
-			}
-		*/
-			audio.stop();
-		}
-		
-//		std::cout << metadata["previous bgm"] << std::endl;
-
-		audio.load(filename);
-		audio.setVolume(metadata["volumes"]["bgm"].asFloat());
-		audio.play();
-
-		return "true";
-	});
 	{
 		static uf::Timer<long long> timer(false);
 		if ( !timer.running() ) timer.start();
@@ -115,6 +94,9 @@ void ext::TestScene::initialize() {
 	}
 }
 
+void ext::TestScene::render() {
+	uf::Scene::render();
+}
 void ext::TestScene::tick() {
 	uf::Scene::tick();
 
@@ -138,4 +120,57 @@ void ext::TestScene::tick() {
 		ext::oal.listener( "VELOCITY", { 0, 0, 0 } );
 		ext::oal.listener( "ORIENTATION", { 0, 0, 1, 1, 0, 0 } );
 	}
+
+	/* Collision */ {
+		bool local = false;
+		bool sort = false;
+		bool useStrongest = false;
+	//	pod::Thread& thread = uf::thread::fetchWorker();
+		pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+		auto function = [&]() -> int {
+			std::vector<uf::Object*> entities;
+			std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
+				auto& metadata = entity->getComponent<uf::Serializer>();
+				if ( !metadata["system"]["physics"]["collision"].isNull() && !metadata["system"]["physics"]["collision"].asBool() ) return;
+				if ( entity->hasComponent<uf::Collider>() )
+					entities.push_back((uf::Object*) entity);
+			};
+			this->process(filter);
+			auto onCollision = []( pod::Collider::Manifold& manifold, uf::Object* a, uf::Object* b ){				
+				uf::Serializer payload;
+				payload["normal"][0] = manifold.normal.x;
+				payload["normal"][1] = manifold.normal.y;
+				payload["normal"][2] = manifold.normal.z;
+				payload["entity"] = b->getUid();
+				payload["depth"] = -manifold.depth;
+				a->callHook("world:Collision.%UID%", payload);
+				
+				payload["entity"] = a->getUid();
+				payload["depth"] = manifold.depth;
+				b->callHook("world:Collision.%UID%", payload);
+			};
+			auto testColliders = [&]( uf::Collider& colliderA, uf::Collider& colliderB, uf::Object* a, uf::Object* b, bool useStrongest ){
+				pod::Collider::Manifold strongest;
+				auto manifolds = colliderA.intersects(colliderB);
+				for ( auto manifold : manifolds ) {
+					if ( manifold.colliding && manifold.depth > 0 ) {
+						if ( !useStrongest ) onCollision(manifold, a, b);
+						else if ( strongest.depth < manifold.depth ) strongest = manifold;
+					}
+				}
+				if ( useStrongest && strongest.colliding ) onCollision(strongest, a, b);
+			};
+			// collide with others
+			for ( auto* _a : entities ) {
+				uf::Object& entityA = *_a;
+				for ( auto* _b : entities ) { if ( _a == _b ) continue;
+					uf::Object& entityB = *_b;
+					testColliders( entityA.getComponent<uf::Collider>(), entityB.getComponent<uf::Collider>(), &entityA, &entityB, useStrongest );
+				}
+			}
+		
+			return 0;
+		};
+		if ( local ) function(); else uf::thread::add( thread, function, true );
+	}
 }
\ No newline at end of file
diff --git a/ext/scenes/test/scene.h b/ext/scenes/test/scene.h
index 058a9d6d..96b6ec51 100644
--- a/ext/scenes/test/scene.h
+++ b/ext/scenes/test/scene.h
@@ -10,5 +10,6 @@ namespace ext {
 	public:
 		virtual void initialize();
 		virtual void tick();
+		virtual void render();
 	};
 }
\ No newline at end of file
diff --git a/ext/scenes/world/craeture/craeture.cpp b/ext/scenes/world/craeture/craeture.cpp
index c139c9ec..e9458d9b 100644
--- a/ext/scenes/world/craeture/craeture.cpp
+++ b/ext/scenes/world/craeture/craeture.cpp
@@ -44,19 +44,24 @@ void ext::Craeture::initialize() {
 	}
 */
 	/* Gravity */ {
-		if ( metadata["collision"]["gravity"] != Json::nullValue ) {
-			physics.linear.acceleration.x = metadata["collision"]["gravity"][0].asFloat();
-			physics.linear.acceleration.y = metadata["collision"]["gravity"][1].asFloat();
-			physics.linear.acceleration.z = metadata["collision"]["gravity"][2].asFloat();
+		if ( metadata["system"]["physics"]["gravity"] != Json::nullValue ) {
+			physics.linear.acceleration.x = metadata["system"]["physics"]["gravity"][0].asFloat();
+			physics.linear.acceleration.y = metadata["system"]["physics"]["gravity"][1].asFloat();
+			physics.linear.acceleration.z = metadata["system"]["physics"]["gravity"][2].asFloat();
 		}
-		if ( !metadata["collision"]["should"].asBool() )  {
+		if ( !metadata["system"]["physics"]["collision"].asBool() )  {
 			physics.linear.acceleration.x = 0;
 			physics.linear.acceleration.y = 0;
 			physics.linear.acceleration.z = 0;
 		}
 	}
 	/* Collider */ {
-		uf::CollisionBody& collider = this->getComponent<uf::CollisionBody>();
+		uf::Collider& collider = this->getComponent<uf::Collider>();
+
+		collider.clear();
+		auto* box = new uf::BoundingBox( {0, 1.5, 0}, {0.7, 1.6, 0.7} );
+		box->getTransform().reference = &transform;
+		collider.add(box);
 	}
 	/* RPG */ {
 		ext::HousamoBattle& battle = this->getComponent<ext::HousamoBattle>();
@@ -70,6 +75,28 @@ void ext::Craeture::initialize() {
 	} timers;
 */
 	static uf::Timer<long long> timer(true);
+	this->addHook( "world:Collision.%UID%", [&](const std::string& event)->std::string{	
+		uf::Serializer json = event;
+
+		size_t uid = json["uid"].asUInt64();
+		// do not collide with children
+		// if ( this->findByUid(uid) ) return "false";
+
+		pod::Vector3 normal;
+		float depth = json["depth"].asFloat() * 1.001f;
+
+		normal.x = json["normal"][0].asFloat();
+		normal.y = json["normal"][1].asFloat();
+		normal.z = json["normal"][2].asFloat();
+		pod::Vector3 correction = normal * depth;
+
+		transform.position -= correction;
+
+		if ( normal.x == 1 || normal.x == -1 ) physics.linear.velocity.x = 0;
+		if ( normal.y == 1 || normal.y == -1 ) physics.linear.velocity.y = 0;
+		if ( normal.z == 1 || normal.z == -1 ) physics.linear.velocity.z = 0;
+		return "true";
+	});
 	this->addHook( "asset:Cache.Sound.%UID%", [&](const std::string& event)->std::string{	
 		uf::Serializer json = event;
 		
@@ -148,157 +175,157 @@ void ext::Craeture::tick() {
 	pod::Transform<>& transform = this->getComponent<pod::Transform<>>();
 	pod::Physics& physics = this->getComponent<pod::Physics>();
 	/* Gravity */ {
-		if ( metadata["collision"]["gravity"] != Json::nullValue ) {
-			physics.linear.acceleration.x = metadata["collision"]["gravity"][0].asFloat();
-			physics.linear.acceleration.y = metadata["collision"]["gravity"][1].asFloat();
-			physics.linear.acceleration.z = metadata["collision"]["gravity"][2].asFloat();
+		if ( metadata["system"]["physics"]["gravity"] != Json::nullValue ) {
+			physics.linear.acceleration.x = metadata["system"]["physics"]["gravity"][0].asFloat();
+			physics.linear.acceleration.y = metadata["system"]["physics"]["gravity"][1].asFloat();
+			physics.linear.acceleration.z = metadata["system"]["physics"]["gravity"][2].asFloat();
 		}
-		if ( !metadata["collision"]["should"].asBool() )  {
+		if ( !metadata["system"]["physics"]["collision"].asBool() )  {
 			physics.linear.acceleration.x = 0;
 			physics.linear.acceleration.y = 0;
 			physics.linear.acceleration.z = 0;
 		}
 	}
 	transform = uf::physics::update( transform, physics );
+#if 0
+	if ( !false ) {
+		bool sort = false;
+		bool local = false;
+		bool useStrongest = true;
+		pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+		auto onCollision = []( pod::Collider::Manifold& manifold, uf::Object* a, uf::Object* b ){				
+			pod::Transform<>& transform = b->getComponent<pod::Transform<>>();
+			pod::Physics& physics = b->getComponent<pod::Physics>();
 
-	bool local = false;
-	bool sort = false;
-//	pod::Thread& thread = uf::thread::fetchWorker();
-	pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+			uf::Serializer payload;
+			pod::Vector3 correction = manifold.normal * manifold.depth;
+			transform.position -= correction;
 
-	/* Collision against world */ {
-		auto function = [&]() -> int {
-			if ( this->hasParent() && metadata["collision"]["should"].asBool() ) {
-				if ( !this->hasParent() ) { return 0; }
-				if ( this->getParent().getName() != "Region" ) { return 0; }
-
-				uf::Entity& parent = this->getParent();
-				ext::TerrainGenerator& generator = parent.getComponent<ext::TerrainGenerator>();
-				uf::Serializer& rMetadata = parent.getComponent<uf::Serializer>();
-				pod::Transform<>& rTransform = parent.getComponent<pod::Transform<>>();
-
-				pod::Vector3ui size; {
-					size.x = rMetadata["region"]["size"][0].asUInt();
-					size.y = rMetadata["region"]["size"][1].asUInt();
-					size.z = rMetadata["region"]["size"][2].asUInt();
-				}
-				pod::Vector3f voxelPosition = transform.position - rTransform.position;
-				voxelPosition.x += size.x / 2.0f;
-				voxelPosition.y += size.y / 2.0f + 1;
-				voxelPosition.z += size.z / 2.0f;	
-
-				uf::CollisionBody pCollider;
-				std::vector<pod::Vector3ui> positions = {
-					{ voxelPosition.x, voxelPosition.y, voxelPosition.z },
-					{ voxelPosition.x - 1, voxelPosition.y, voxelPosition.z },
-					{ voxelPosition.x + 1, voxelPosition.y, voxelPosition.z },
-					{ voxelPosition.x, voxelPosition.y, voxelPosition.z - 1 },
-					{ voxelPosition.x, voxelPosition.y, voxelPosition.z + 1},
-				};
-				if ( this->m_name == "HousamoSprite" ) {
-					// bottom
-					uint16_t uid = generator.getVoxel( voxelPosition.x, voxelPosition.y, voxelPosition.z );
-					auto light = generator.getLight( voxelPosition.x, voxelPosition.y, voxelPosition.z );
-					metadata["color"][0] = ((light >> 12) & 0xF) / (float) (0xF);
-					metadata["color"][1] = ((light >>  8) & 0xF) / (float) (0xF);
-					metadata["color"][2] = ((light >>  4) & 0xF) / (float) (0xF);
-					metadata["color"][3] = ((light      ) & 0xF) / (float) (0xF);
-				/*
-					if ( uid == ext::TerrainVoxelLava().uid() ) {
-						this->callHook("world:Craeture.Hurt.%UID%");
-					}
-				*/
-				}
-
-				if ( false ) {
-					// top
-					if ( ext::TerrainVoxel::atlas( generator.getVoxel( voxelPosition.x, voxelPosition.y + 1, voxelPosition.z ) ).solid() && physics.linear.velocity.y != 0 ) {
-						transform.position.y += physics.linear.velocity.y * uf::physics::time::delta;
-						physics.linear.velocity.y = 0;
-					}
-					// bottom
-					if ( ext::TerrainVoxel::atlas( generator.getVoxel( voxelPosition.x, voxelPosition.y - 1, voxelPosition.z ) ).solid() && physics.linear.velocity.y != 0 ) {
-						transform.position.y -= physics.linear.velocity.y * uf::physics::time::delta;
-						physics.linear.velocity.y = 0;
-					}
-				} else {
-					positions.push_back( { voxelPosition.x, voxelPosition.y - 1, voxelPosition.z } );
-					positions.push_back( { voxelPosition.x, voxelPosition.y + 1, voxelPosition.z } );
-				}
-
-				for ( auto& position : positions ) {
-					ext::TerrainVoxel voxel = ext::TerrainVoxel::atlas( generator.getVoxel( position.x, position.y, position.z ) );
-					pod::Vector3 offset = rTransform.position;
-					offset.x += position.x - (size.x / 2.0f);
-					offset.y += position.y - (size.y / 2.0f);
-					offset.z += position.z - (size.z / 2.0f);
-
-					if ( !voxel.solid() ) continue;
-
-					uf::Collider* box = new uf::AABBox( offset, {0.5, 0.5, 0.5} );
-					pCollider.add(box);
-				}
-
-				uf::CollisionBody& collider = this->getComponent<uf::CollisionBody>();
-				pod::Transform<>& transform = this->getComponent<pod::Transform<>>(); {
-					collider.clear();
-					uf::Collider* box = new uf::AABBox( uf::vector::add({0, 1.5, 0}, transform.position), {0.7, 1.6, 0.7} );
-					collider.add(box);
-				}
-
-				pod::Physics& physics = this->getComponent<pod::Physics>();
-				auto result = pCollider.intersects(collider);
-				uf::Collider::Manifold strongest;
-				strongest.depth = 0.001;
-				bool useStrongest = true;
-				for ( auto manifold : result ) {
-					if ( manifold.colliding && manifold.depth > 0 ) {
-						if ( strongest.depth < manifold.depth ) strongest = manifold;
-						if ( !useStrongest ) {
-							pod::Vector3 correction = uf::vector::normalize(manifold.normal) * -(manifold.depth * manifold.depth * 1.001);
-							transform.position += correction;
-							if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
-							if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
-							if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
-						}
-					}
-				}
-				if ( useStrongest && strongest.colliding ) {
-					pod::Vector3 correction = uf::vector::normalize(strongest.normal) * -(strongest.depth * strongest.depth * 1.001);
-					transform.position += correction;
-
-				//	std::cout << "Collision! " << ( strongest.colliding ? "yes" : "no" ) << " " << strongest.normal.x << ", " << strongest.normal.y << ", " << strongest.normal.z << " / " << strongest.depth << std::endl;
-					if ( strongest.normal.x == 1 || strongest.normal.x == -1 ) physics.linear.velocity.x = 0;
-					if ( strongest.normal.y == 1 || strongest.normal.y == -1 ) physics.linear.velocity.y = 0;
-					if ( strongest.normal.z == 1 || strongest.normal.z == -1 ) physics.linear.velocity.z = 0;
+			if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
+			if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
+			if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
+		};
+		auto testColliders = [&]( uf::Collider& colliderA, uf::Collider& colliderB, uf::Object* a, uf::Object* b, bool useStrongest ){
+			pod::Collider::Manifold strongest;
+			auto manifolds = colliderA.intersects(colliderB);
+			for ( auto manifold : manifolds ) {
+				if ( manifold.colliding && manifold.depth > 0 ) {
+					if ( !useStrongest ) onCollision(manifold, a, b);
+					else if ( strongest.depth < manifold.depth ) strongest = manifold;
 				}
 			}
-			return 0;
+			if ( useStrongest && strongest.colliding ) onCollision(strongest, a, b);
 		};
-		if ( local ) function(); else uf::thread::add( thread, function, true );
-	}
+		/* Collision against world */ {
+			auto function = [&]() -> int {
+				if ( this->hasParent() && metadata["system"]["physics"]["collision"].asBool() ) {
+					if ( !this->hasParent() ) { return 0; }
+					if ( this->getParent().getName() != "Region" ) { return 0; }
 
-	/* Collision against world */ if ( false ) {
-		auto function = [&]() -> int {
-			if ( this->hasParent() && metadata["collision"]["should"].asBool() ) {
-				if ( !this->hasParent() ) { return 0; }
-				if ( this->getName() == "Player" ) { return 0; }
-				if ( this->getParent().getName() != "Region" ) { return 0; }
-				if ( !this->getParent().hasParent() ) { return 0; }
-				if ( this->getParent().getParent().getName() != "Terrain" ) { return 0; }
+					uf::Entity& parent = this->getParent();
+					ext::TerrainGenerator& generator = parent.getComponent<ext::TerrainGenerator>();
+					uf::Serializer& rMetadata = parent.getComponent<uf::Serializer>();
+					pod::Transform<>& rTransform = parent.getComponent<pod::Transform<>>();
 
-				uf::Entity& parentRegion = this->getParent();
-				uf::Entity& parentTerrain = parentRegion.getParent();
+					pod::Vector3ui size; {
+						size.x = rMetadata["region"]["size"][0].asUInt();
+						size.y = rMetadata["region"]["size"][1].asUInt();
+						size.z = rMetadata["region"]["size"][2].asUInt();
+					}
+					pod::Vector3f voxelPosition = transform.position - rTransform.position;
+					voxelPosition.x += size.x / 2.0f;
+					voxelPosition.y += size.y / 2.0f + 1;
+					voxelPosition.z += size.z / 2.0f;	
 
-				int regions = 0;
-				std::vector<uf::Entity*> entities;
-				entities.push_back(&parentRegion);
-				if ( false ) {
-					/* Retrieve close entities */ for ( uf::Entity* kv : parentTerrain.getChildren() ) { if ( !kv ) continue; if ( kv->getName() != "Region" ) continue;
-						if ( kv->getUid() == parentRegion.getUid() ) continue;
-						uf::Serializer& rMetadata = kv->getComponent<uf::Serializer>();
-						if ( !rMetadata["region"]["initialized"].asBool() ) continue;
-						if ( ++regions <= 2 ) entities.push_back(kv);
+					uf::Collider pCollider;
+					std::vector<pod::Vector3ui> positions = {
+						{ voxelPosition.x, voxelPosition.y, voxelPosition.z },
+						{ voxelPosition.x - 1, voxelPosition.y, voxelPosition.z },
+						{ voxelPosition.x + 1, voxelPosition.y, voxelPosition.z },
+						{ voxelPosition.x, voxelPosition.y - 1, voxelPosition.z },
+						{ voxelPosition.x, voxelPosition.y + 1, voxelPosition.z },
+						{ voxelPosition.x, voxelPosition.y, voxelPosition.z - 1 },
+						{ voxelPosition.x, voxelPosition.y, voxelPosition.z + 1},
+					};
+					if ( this->m_name == "HousamoSprite" ) {
+						// bottom
+						uint16_t uid = generator.getVoxel( voxelPosition.x, voxelPosition.y, voxelPosition.z );
+						auto light = generator.getLight( voxelPosition.x, voxelPosition.y, voxelPosition.z );
+						metadata["color"][0] = ((light >> 12) & 0xF) / (float) (0xF);
+						metadata["color"][1] = ((light >>  8) & 0xF) / (float) (0xF);
+						metadata["color"][2] = ((light >>  4) & 0xF) / (float) (0xF);
+						metadata["color"][3] = ((light      ) & 0xF) / (float) (0xF);
+					//	if ( uid == ext::TerrainVoxelLava().uid() ) this->callHook("world:Craeture.Hurt.%UID%");
+					}
+
+					for ( auto& position : positions ) {
+						ext::TerrainVoxel voxel = ext::TerrainVoxel::atlas( generator.getVoxel( position.x, position.y, position.z ) );
+						pod::Vector3 offset = rTransform.position;
+						offset.x += position.x - (size.x / 2.0f);
+						offset.y += position.y - (size.y / 2.0f);
+						offset.z += position.z - (size.z / 2.0f);
+
+						if ( !voxel.solid() ) continue;
+
+						pCollider.add( new uf::BoundingBox( offset, {0.5, 0.5, 0.5} ) );
+					}
+
+					uf::Collider& collider = this->getComponent<uf::Collider>();
+					pod::Transform<>& transform = this->getComponent<pod::Transform<>>();
+				
+					{
+						collider.clear();
+						collider.add(new uf::BoundingBox( uf::vector::add({0, 1.5, 0}, transform.position), {0.7, 1.6, 0.7} ));
+					}
+				
+
+					pod::Physics& physics = this->getComponent<pod::Physics>();
+
+					auto result = pCollider.intersects(collider);
+					pod::Collider::Manifold strongest;
+
+					for ( auto manifold : result ) {
+						if ( manifold.colliding && manifold.depth > 0 ) {
+							if ( strongest.depth < manifold.depth ) strongest = manifold;
+							if ( !useStrongest ) {
+								pod::Vector3 correction = manifold.normal * manifold.depth;
+								transform.position -= correction;
+
+								if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
+								if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
+								if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
+							}
+						}
+					}
+					if ( useStrongest && strongest.colliding ) {
+						pod::Vector3 correction = strongest.normal * strongest.depth;
+						transform.position -= correction;
+
+						if ( strongest.normal.x == 1 || strongest.normal.x == -1 ) physics.linear.velocity.x = 0;
+						if ( strongest.normal.y == 1 || strongest.normal.y == -1 ) physics.linear.velocity.y = 0;
+						if ( strongest.normal.z == 1 || strongest.normal.z == -1 ) physics.linear.velocity.z = 0;
+					}
+				}
+				return 0;
+			};
+			if ( local ) function(); else uf::thread::add( thread, function, true );
+		}
+
+		/* Collision against other craetures */ {
+			auto function = [&]() -> int {
+				/* Collision */ if ( this->hasParent() && metadata["system"]["physics"]["collision"].asBool() ) {
+					if ( !this->hasParent() ) { return 0; }
+					if ( this->getParent().getName() != "Region" ) { return 0; }
+
+					uf::Entity& parent = this->getParent();
+
+					int regions = 0;
+					std::vector<uf::Entity*> entities;
+					/* Retrieve close entities */ for ( uf::Entity* kv : parent.getChildren() ) {
+						if ( !kv ) continue;
+						if ( kv->getUid() == this->getUid() ) continue;
+						if ( !kv->hasComponent<uf::Collider>() ) continue;
+						entities.push_back(kv);
 					}
 					/* Sort by closest to farthest */ if ( sort ) {
 						const pod::Vector3& position = this->getComponent<pod::Transform<>>().position;
@@ -309,146 +336,284 @@ void ext::Craeture::tick() {
 							return uf::vector::magnitude( uf::vector::subtract( l->getComponent<pod::Transform<>>().position, position ) ) < uf::vector::magnitude( uf::vector::subtract( r->getComponent<pod::Transform<>>().position, position ) );
 						} );
 					}
-				}
 
-				for ( uf::Entity* e : entities ) {
-					uf::CollisionBody& collider = this->getComponent<uf::CollisionBody>();
-					uf::CollisionBody& pCollider = e->getComponent<uf::CollisionBody>();
+					for ( uf::Entity* e : entities ) {
+						if ( e->getUid() == 0 ) continue;
 
-					pod::Transform<>& transform = this->getComponent<pod::Transform<>>(); {
-						collider.clear();
-						uf::Collider* box = new uf::AABBox( uf::vector::add({0, 1.5, 0}, transform.position), {0.7, 1.6, 0.7} );
-						collider.add(box);
-					}
+						uf::Collider& collider = this->getComponent<uf::Collider>();
+						uf::Collider& pCollider = e->getComponent<uf::Collider>();
 
-					if ( !e ) continue;
-					if ( e->getUid() == 0 ) continue;
-					if ( this->getUid() == 0 ) return 0;
-					if ( !this->hasComponent<pod::Physics>() ) return 0;
-
-					pod::Physics& physics = this->getComponent<pod::Physics>();
-					auto result = pCollider.intersects(collider);
-					uf::Collider::Manifold strongest;
-					strongest.depth = 0.001;
-					bool useStrongest = true;
-					for ( auto manifold : result ) {
-						if ( manifold.colliding && manifold.depth > 0 ) {
-							if ( strongest.depth < manifold.depth ) strongest = manifold;
-							if ( !useStrongest ) {
-								pod::Vector3 correction = uf::vector::normalize(manifold.normal) * -(manifold.depth * manifold.depth * 1.001);
-								transform.position += correction;
-								if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
-								if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
-								if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
-							}
-						}
-					}
-					if ( useStrongest && strongest.colliding ) {
-						pod::Vector3 correction = uf::vector::normalize(strongest.normal) * -(strongest.depth * strongest.depth * 1.001);
-						transform.position += correction;
-
-					//	std::cout << "Collision! " << ( strongest.colliding ? "yes" : "no" ) << " " << strongest.normal.x << ", " << strongest.normal.y << ", " << strongest.normal.z << " / " << strongest.depth << std::endl;
-						if ( strongest.normal.x == 1 || strongest.normal.x == -1 ) physics.linear.velocity.x = 0;
-						if ( strongest.normal.y == 1 || strongest.normal.y == -1 ) physics.linear.velocity.y = 0;
-						if ( strongest.normal.z == 1 || strongest.normal.z == -1 ) physics.linear.velocity.z = 0;
-					}
-				}
-			}
-			return 0;
-		};
-		if ( local ) function(); else uf::thread::add( thread, function, true );
-	}
-
-	/* Collision against other craetures */ {
-		auto function = [&]() -> int {
-			/* Collision */ if ( this->hasParent() && metadata["collision"]["should"].asBool() ) {
-				if ( !this->hasParent() ) { return 0; }
-				if ( this->getParent().getName() != "Region" ) { return 0; }
-
-				uf::Entity& parent = this->getParent();
-
-				int regions = 0;
-				std::vector<uf::Entity*> entities;
-				/* Retrieve close entities */ for ( uf::Entity* kv : parent.getChildren() ) {
-					if ( !kv ) continue;
-					if ( kv->getUid() == this->getUid() ) continue;
-					if ( !kv->hasComponent<uf::CollisionBody>() ) continue;
-					entities.push_back(kv);
-				}
-				/* Sort by closest to farthest */ if ( sort ) {
-					const pod::Vector3& position = this->getComponent<pod::Transform<>>().position;
-					std::sort( entities.begin(), entities.end(), [&]( const uf::Entity* l, const uf::Entity* r ){
-						if ( !l ) return false; if ( !r ) return true;
-						if ( l->getUid() == 0 ) return false; if ( r->getUid() == 0 ) return true;
-						if ( !l->hasComponent<pod::Transform<>>() ) return false; if ( !r->hasComponent<pod::Transform<>>() ) return true;
-						return uf::vector::magnitude( uf::vector::subtract( l->getComponent<pod::Transform<>>().position, position ) ) < uf::vector::magnitude( uf::vector::subtract( r->getComponent<pod::Transform<>>().position, position ) );
-					} );
-				}
-
-				for ( uf::Entity* e : entities ) {
-					if ( e->getUid() == 0 ) continue;
-
-					uf::CollisionBody& collider = this->getComponent<uf::CollisionBody>();
-					uf::CollisionBody& pCollider = e->getComponent<uf::CollisionBody>();
-
-					pod::Transform<>& transform = this->getComponent<pod::Transform<>>(); {
-						collider.clear();
-						uf::Collider* box = new uf::AABBox( uf::vector::add({0, 1.5, 0}, transform.position), {0.7, 1.6, 0.7} );
-						collider.add(box);
-					}
-
-					pod::Physics& physics = this->getComponent<pod::Physics>();
-					auto result = pCollider.intersects(collider);
-					uf::Collider::Manifold strongest;
-					strongest.depth = 0.001;
-					bool useStrongest = true;
-					for ( auto manifold : result ) {
-						if ( manifold.colliding && manifold.depth > 0 ) {
-							if ( strongest.depth < manifold.depth ) strongest = manifold;
-							if ( !useStrongest ) {
-								pod::Vector3 correction = uf::vector::normalize(manifold.normal) * -(manifold.depth * manifold.depth * 1.001);
-								transform.position += correction;
-								if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
-								if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
-								if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
-							}
-						}
-					}
-
-					uf::Serializer& metadata = this->getComponent<uf::Serializer>();
-					uf::Serializer& pSerializer = e->getComponent<uf::Serializer>();
-
-
-					if ( useStrongest && strongest.colliding ) {
-						// signal collision, if available
-						pod::Vector3 correction = uf::vector::normalize(strongest.normal) * -(strongest.depth * strongest.depth * 1.001);
+						pod::Physics& physics = this->getComponent<pod::Physics>();
+						pod::Transform<>& transform = this->getComponent<pod::Transform<>>();
+					
 						{
-							uf::Serializer payload;
-							payload["entity"] = e->getUid();
-							payload["correction"]["x"] = correction.x;
-							payload["correction"]["y"] = correction.y;
-							payload["correction"]["z"] = correction.z;
-							payload["depth"] = strongest.depth;
-							payload["normal"]["x"] = strongest.normal.x;
-							payload["normal"]["y"] = strongest.normal.y;
-							payload["normal"]["z"] = strongest.normal.z;
-							uf::hooks.call("world:Collision." + std::to_string(this->getUid()), payload);
+							collider.clear();
+							collider.add(new uf::BoundingBox( uf::vector::add({0, 1.5, 0}, transform.position), {0.7, 1.6, 0.7} ));
+						}
+					
+						
+						auto result = pCollider.intersects(collider);
+						
+						pod::Collider::Manifold strongest;
+
+						for ( auto manifold : result ) {
+							if ( manifold.colliding && manifold.depth > 0 ) {
+								if ( strongest.depth < manifold.depth ) strongest = manifold;
+								if ( !useStrongest ) {
+									pod::Vector3 correction = manifold.normal * manifold.depth;
+									transform.position += correction;
+									if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
+									if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
+									if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
+								}
+							}
 						}
 
-						transform.position += correction;
+						uf::Serializer& metadata = this->getComponent<uf::Serializer>();
+						uf::Serializer& pSerializer = e->getComponent<uf::Serializer>();
 
-					//	std::cout << "Collision! " << ( strongest.colliding ? "yes" : "no" ) << " " << strongest.normal.x << ", " << strongest.normal.y << ", " << strongest.normal.z << " / " << strongest.depth << std::endl;
 
-						if ( strongest.normal.x == 1 || strongest.normal.x == -1 ) physics.linear.velocity.x = 0;
-						if ( strongest.normal.y == 1 || strongest.normal.y == -1 ) physics.linear.velocity.y = 0;
-						if ( strongest.normal.z == 1 || strongest.normal.z == -1 ) physics.linear.velocity.z = 0;
+						if ( useStrongest && strongest.colliding ) {
+							// signal collision, if available
+							pod::Vector3 correction = strongest.normal * strongest.depth;
+							{
+								uf::Serializer payload;
+								payload["entity"] = e->getUid();
+								payload["correction"]["x"] = correction.x;
+								payload["correction"]["y"] = correction.y;
+								payload["correction"]["z"] = correction.z;
+								payload["depth"] = strongest.depth;
+								payload["normal"]["x"] = strongest.normal.x;
+								payload["normal"]["y"] = strongest.normal.y;
+								payload["normal"]["z"] = strongest.normal.z;
+								uf::hooks.call("world:Collision." + std::to_string(this->getUid()), payload);
+							}
+							transform.position -= correction;
+
+							if ( strongest.normal.x == 1 || strongest.normal.x == -1 ) physics.linear.velocity.x = 0;
+							if ( strongest.normal.y == 1 || strongest.normal.y == -1 ) physics.linear.velocity.y = 0;
+							if ( strongest.normal.z == 1 || strongest.normal.z == -1 ) physics.linear.velocity.z = 0;
+						}
 					}
 				}
+				return 0;
+			};
+			if ( local ) function(); else uf::thread::add( thread, function, true );
+		}
+	} else if ( false ) {
+		bool sort = false;
+		bool local = false;
+		bool useStrongest = true;
+		pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+		auto onCollision = []( pod::Collider::Manifold& manifold, uf::Object* a, uf::Object* b ){				
+			pod::Transform<>& transform = b->getComponent<pod::Transform<>>();
+			pod::Physics& physics = b->getComponent<pod::Physics>();
+
+			uf::Serializer payload;
+			pod::Vector3 correction = manifold.normal * manifold.depth;
+			transform.position -= correction;
+
+			if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
+			if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
+			if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
+		};
+		auto testColliders = [&]( uf::Collider& colliderA, uf::Collider& colliderB, uf::Object* a, uf::Object* b, bool useStrongest ){
+			pod::Collider::Manifold strongest;
+			auto manifolds = colliderA.intersects(colliderB);
+			for ( auto manifold : manifolds ) {
+				if ( manifold.colliding && manifold.depth > 0 ) {
+					if ( !useStrongest ) onCollision(manifold, a, b);
+					else if ( strongest.depth < manifold.depth ) strongest = manifold;
+				}
 			}
+			if ( useStrongest && strongest.colliding ) onCollision(strongest, a, b);
+		};
+		/* Collision against world */ {
+			auto function = [&]() -> int {
+				if ( this->hasParent() && metadata["system"]["physics"]["collision"].asBool() ) {
+					if ( !this->hasParent() ) { return 0; }
+					if ( this->getParent().getName() != "Region" ) { return 0; }
+
+					uf::Entity& parent = this->getParent();
+					ext::TerrainGenerator& generator = parent.getComponent<ext::TerrainGenerator>();
+					uf::Serializer& rMetadata = parent.getComponent<uf::Serializer>();
+					pod::Transform<>& rTransform = parent.getComponent<pod::Transform<>>();
+
+					pod::Vector3ui size; {
+						size.x = rMetadata["region"]["size"][0].asUInt();
+						size.y = rMetadata["region"]["size"][1].asUInt();
+						size.z = rMetadata["region"]["size"][2].asUInt();
+					}
+					pod::Vector3f voxelPosition = transform.position - rTransform.position;
+					voxelPosition.x += size.x / 2.0f;
+					voxelPosition.y += size.y / 2.0f + 1;
+					voxelPosition.z += size.z / 2.0f;	
+
+					uf::Collider pCollider;
+					std::vector<pod::Vector3ui> positions = {
+						{ voxelPosition.x, voxelPosition.y, voxelPosition.z },
+						{ voxelPosition.x - 1, voxelPosition.y, voxelPosition.z },
+						{ voxelPosition.x + 1, voxelPosition.y, voxelPosition.z },
+						{ voxelPosition.x, voxelPosition.y - 1, voxelPosition.z },
+						{ voxelPosition.x, voxelPosition.y + 1, voxelPosition.z },
+						{ voxelPosition.x, voxelPosition.y, voxelPosition.z - 1 },
+						{ voxelPosition.x, voxelPosition.y, voxelPosition.z + 1},
+					};
+					if ( this->m_name == "HousamoSprite" ) {
+						uint16_t uid = generator.getVoxel( voxelPosition.x, voxelPosition.y, voxelPosition.z );
+						auto light = generator.getLight( voxelPosition.x, voxelPosition.y, voxelPosition.z );
+						metadata["color"][0] = ((light >> 12) & 0xF) / (float) (0xF);
+						metadata["color"][1] = ((light >>  8) & 0xF) / (float) (0xF);
+						metadata["color"][2] = ((light >>  4) & 0xF) / (float) (0xF);
+						metadata["color"][3] = ((light      ) & 0xF) / (float) (0xF);
+					//	if ( uid == ext::TerrainVoxelLava().uid() ) this->callHook("world:Craeture.Hurt.%UID%");
+					}
+
+					for ( auto& position : positions ) {
+						ext::TerrainVoxel voxel = ext::TerrainVoxel::atlas( generator.getVoxel( position.x, position.y, position.z ) );
+						pod::Vector3 offset = rTransform.position;
+						offset.x += position.x - (size.x / 2.0f);
+						offset.y += position.y - (size.y / 2.0f);
+						offset.z += position.z - (size.z / 2.0f);
+
+						if ( !voxel.solid() ) continue;
+
+						pCollider.add( new uf::BoundingBox( offset, {0.5, 0.5, 0.5} ) );
+					}
+
+					uf::Collider& collider = this->getComponent<uf::Collider>();
+					testColliders( pCollider, collider, (uf::Object*) &parent, this, useStrongest );
+				}
+				return 0;
+			};
+			if ( local ) function(); else uf::thread::add( thread, function, true );
+		}
+	} else if ( false ) {
+		bool local = false;
+		bool sort = false;
+		bool useStrongest = false;
+		pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+		auto function = [&]() -> int {
+			std::vector<uf::Object*> entities;
+			std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
+				auto& metadata = entity->getComponent<uf::Serializer>();
+				if ( !metadata["system"]["physics"]["collision"].isNull() && !metadata["system"]["physics"]["collision"].asBool() ) return;
+				if ( entity->hasComponent<uf::Collider>() )
+					entities.push_back((uf::Object*) entity);
+			};
+			uf::Entity* regionPointer = &this->getParent();
+			if ( regionPointer->getName() != "Region" ) return 0;
+			ext::Region& region = *(ext::Region*) regionPointer;
+			region.process(filter);
+			auto onCollision = []( pod::Collider::Manifold& manifold, uf::Object* a, uf::Object* b ){				
+				uf::Serializer payload;
+				payload["normal"][0] = manifold.normal.x;
+				payload["normal"][1] = manifold.normal.y;
+				payload["normal"][2] = manifold.normal.z;
+				payload["entity"] = b->getUid();
+				payload["depth"] = -manifold.depth;
+				a->callHook("world:Collision.%UID%", payload);
+				
+				payload["entity"] = a->getUid();
+				payload["depth"] = manifold.depth;
+				b->callHook("world:Collision.%UID%", payload);
+			};
+			auto testColliders = [&]( uf::Collider& colliderA, uf::Collider& colliderB, uf::Object* a, uf::Object* b, bool useStrongest ){
+				pod::Collider::Manifold strongest;
+				auto manifolds = colliderA.intersects(colliderB);
+				for ( auto manifold : manifolds ) {
+					if ( manifold.colliding && manifold.depth > 0 ) {
+						if ( !useStrongest ) onCollision(manifold, a, b);
+						else if ( strongest.depth < manifold.depth ) strongest = manifold;
+					}
+				}
+				if ( useStrongest && strongest.colliding ) onCollision(strongest, a, b);
+			};
+
+			// collide with world
+			auto& metadata = region.getComponent<uf::Serializer>();
+			auto& generator = region.getComponent<ext::TerrainGenerator>();
+			auto& regionPosition = region.getComponent<pod::Transform<>>().position;
+			pod::Vector3f size; {
+				size.x = metadata["region"]["size"][0].asUInt();
+				size.y = metadata["region"]["size"][1].asUInt();
+				size.z = metadata["region"]["size"][2].asUInt();
+			}
+			for ( auto* _ : entities ) {
+				uf::Object& entity = *_;
+				auto& transform = entity.getComponent<pod::Transform<>>();
+			
+				pod::Vector3f voxelPosition = transform.position - regionPosition;
+				voxelPosition.x += size.x / 2.0f;
+				voxelPosition.y += size.y / 2.0f + 1;
+				voxelPosition.z += size.z / 2.0f;
+
+				uf::Collider collider;
+				std::vector<pod::Vector3ui> positions = {
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x - 1, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x + 1, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y - 1, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y + 1, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z - 1 },
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z + 1},
+				};
+				for ( auto& position : positions ) {
+					ext::TerrainVoxel voxel = ext::TerrainVoxel::atlas( generator.getVoxel( position.x, position.y, position.z ) );
+					pod::Vector3 offset = regionPosition;
+					offset.x += position.x - (size.x / 2.0f);
+					offset.y += position.y - (size.y / 2.0f);
+					offset.z += position.z - (size.z / 2.0f);
+
+					if ( !voxel.solid() ) continue;
+
+					collider.add( new uf::BoundingBox( offset, {0.5, 0.5, 0.5} ) );
+				/*
+					uf::BaseMesh<pod::Vertex_3F> mesh;
+					const ext::TerrainVoxel::Model& model = voxel.model();
+					#define TERRAIN_SHOULD_RENDER_FACE(SIDE)\
+						for ( uint i = 0; i < model.position.SIDE.size() / 3; ++i ) {\
+							auto& vertex = mesh.vertices.emplace_back();\
+							{\
+								pod::Vector3f& p = vertex.position;\
+								p.x = model.position.SIDE[i*3+0]; p.y = model.position.SIDE[i*3+1]; p.z = model.position.SIDE[i*3+2];\
+								p.x += offset.x; p.y += offset.y; p.z += offset.z;\
+							}\
+						}
+					TERRAIN_SHOULD_RENDER_FACE(left)
+					TERRAIN_SHOULD_RENDER_FACE(right)
+					TERRAIN_SHOULD_RENDER_FACE(top)
+					TERRAIN_SHOULD_RENDER_FACE(bottom)
+					TERRAIN_SHOULD_RENDER_FACE(back)
+					TERRAIN_SHOULD_RENDER_FACE(front)
+					uf::MeshCollider* mCollider = new uf::MeshCollider();
+					mCollider->setPositions( mesh );
+					pCollider.add(mCollider);
+				*/
+				}
+				testColliders( collider, entity.getComponent<uf::Collider>(), this, &entity, useStrongest );
+			}
+		
+			// collide with others
+			for ( auto* _a : entities ) {
+				uf::Object& entityA = *_a;
+				for ( auto* _b : entities ) { if ( _a == _b ) continue;
+					uf::Object& entityB = *_b;
+					{
+						uf::Collider& collider = entityB.getComponent<uf::Collider>();
+						pod::Transform<>& transform = entityB.getComponent<pod::Transform<>>(); 
+						collider.clear();
+						collider.add(uf::BoundingBox( uf::vector::add({0, 1.5, 0}, transform.position), {0.7, 1.6, 0.7} ));
+					}
+					testColliders( entityA.getComponent<uf::Collider>(), entityB.getComponent<uf::Collider>(), &entityA, &entityB, useStrongest );
+				}
+			}
+		
 			return 0;
 		};
 		if ( local ) function(); else uf::thread::add( thread, function, true );
 	}
+#endif
 }
 void ext::Craeture::render() {
 	uf::Object::render();
diff --git a/ext/scenes/world/housamo/sprite.cpp b/ext/scenes/world/housamo/sprite.cpp
index 727b0104..93a1f9b8 100644
--- a/ext/scenes/world/housamo/sprite.cpp
+++ b/ext/scenes/world/housamo/sprite.cpp
@@ -136,8 +136,21 @@ void ext::HousamoSprite::render() {
 	if ( !metadata["system"]["loaded"].asBool() ) return;
 
 	ext::Craeture::render();
-	/* Update uniforms */ if ( this->hasComponent<uf::Mesh>() ) {
+	/* Update uniforms */ if ( this->hasComponent<uf::Graphic>() ) {
 		auto& mesh = this->getComponent<uf::Mesh>();
+		auto& scene = this->getRootParent<uf::Scene>();
+		auto& graphic = this->getComponent<uf::Graphic>();
+		auto& transform = this->getComponent<pod::Transform<>>();
+		auto& camera = scene.getController()->getComponent<uf::Camera>();		
+		if ( !graphic.initialized ) return;
+	//	auto& uniforms = graphic.uniforms<uf::StereoMeshDescriptor>();
+		auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
+		uniforms.matrices.model = uf::transform::model( transform );
+		for ( std::size_t i = 0; i < 2; ++i ) {
+			uniforms.matrices.view[i] = camera.getView( i );
+			uniforms.matrices.projection[i] = camera.getProjection( i );
+		}
+	/*
 		auto& graphic = this->getComponent<uf::Graphic>();
 		auto& scene = uf::scene::getCurrentScene();
 		auto& controller = *scene.getController();
@@ -152,6 +165,7 @@ void ext::HousamoSprite::render() {
 			uniforms.matrices.view[i] = camera.getView( i );
 			uniforms.matrices.projection[i] = camera.getProjection( i );
 		}
+	*/
 		uniforms.color[0] = metadata["color"][0].asFloat();
 		uniforms.color[1] = metadata["color"][1].asFloat();
 		uniforms.color[2] = metadata["color"][2].asFloat();
diff --git a/ext/scenes/world/light/light.cpp b/ext/scenes/world/light/light.cpp
index f0abb2b8..4fa3412a 100644
--- a/ext/scenes/world/light/light.cpp
+++ b/ext/scenes/world/light/light.cpp
@@ -3,6 +3,7 @@
 #include <uf/ext/vulkan/rendertarget.h>
 #include <uf/ext/vulkan/rendermodes/rendertarget.h>
 #include <uf/utils/math/transform.h>
+#include <uf/utils/math/physics.h>
 #include <uf/utils/camera/camera.h>
 
 EXT_OBJECT_REGISTER_CPP(Light)
@@ -11,86 +12,64 @@ void ext::Light::initialize() {
 	auto& metadata = this->getComponent<uf::Serializer>();
 	auto& transform = this->getComponent<pod::Transform<>>();
 	auto& camera = this->getComponent<uf::Camera>();
-	{
-		auto& scene = uf::scene::getCurrentScene();
-		auto& controller = *scene.getController();
-		camera = controller.getComponent<uf::Camera>();
-
-		camera.setFov( metadata["light"]["fov"].asFloat() );
-	}
-	{
+	if ( metadata["light"]["shadows"]["enabled"].asBool() ) {
 		auto& renderMode = this->getComponent<ext::vulkan::RenderTargetRenderMode>();
-		renderMode.width = 512;
-		renderMode.height = 512;
 		std::string name = "Render Target: " + std::to_string((int) this->getUid());
 		ext::vulkan::addRenderMode( &renderMode, name );
+		if ( metadata["light"]["shadows"]["resolution"].isArray() ) {
+			renderMode.width = metadata["light"]["shadows"]["resolution"][0].asUInt64();
+			renderMode.height = metadata["light"]["shadows"]["resolution"][1].asUInt64();
+		} else {
+			renderMode.width = metadata["light"]["shadows"]["resolution"].asUInt64();
+			renderMode.height = metadata["light"]["shadows"]["resolution"].asUInt64();
+		}
+		{
+			auto& scene = uf::scene::getCurrentScene();
+			auto& controller = *scene.getController();
+
+			camera = controller.getComponent<uf::Camera>();
+			camera.getTransform() = {};
+			camera.setStereoscopic(false);
+			if ( metadata["light"]["shadows"]["fov"].isNumeric() ) {
+				camera.setFov( metadata["light"]["shadows"]["fov"].asFloat() );
+				camera.updateProjection();
+			}
+		}
+	}
+	if ( !metadata["light"].isArray() ) {
+		metadata["light"]["color"][0] = 1; //metadata["light"]["color"]["random"].asBool() ? (rand() % 100) / 100.0 : 1;
+		metadata["light"]["color"][1] = 1; //metadata["light"]["color"]["random"].asBool() ? (rand() % 100) / 100.0 : 1;
+		metadata["light"]["color"][2] = 1; //metadata["light"]["color"]["random"].asBool() ? (rand() % 100) / 100.0 : 1;
 	}
 }
 void ext::Light::tick() {
 	uf::Object::tick();
 
-	auto& renderMode = this->getComponent<ext::vulkan::RenderTargetRenderMode>();
-	renderMode.target = "";
+	if ( this->hasComponent<ext::vulkan::RenderTargetRenderMode>() ) {
+		auto& renderMode = this->getComponent<ext::vulkan::RenderTargetRenderMode>();
+		renderMode.target = "";
+	}
 	
-	auto& camera = this->getComponent<uf::Camera>();
 	auto& transform = this->getComponent<pod::Transform<>>();
-	for ( std::size_t i = 0; i < 2; ++i ) {
-		camera.setView( uf::matrix::inverse( uf::transform::model( transform ) ), i );
+	if (  this->hasComponent<pod::Physics>() ) {
+		pod::Physics& physics = this->getComponent<pod::Physics>();
+		transform = uf::physics::update( transform, physics );
+	}
+	auto& camera = this->getComponent<uf::Camera>();
+	auto& metadata = this->getComponent<uf::Serializer>();
+	if ( metadata["light"]["external update"].isNull() || (!metadata["light"]["external update"].isNull() && !metadata["light"]["external update"].asBool()) ) {
+		for ( std::size_t i = 0; i < 2; ++i ) {
+			camera.setView( uf::matrix::inverse( uf::transform::model( transform ) ), i );
+		}
 	}
 }
 void ext::Light::render() {
 	uf::Object::render();
-/*
-	{
-		auto& renderMode = this->getComponent<ext::vulkan::RenderTargetRenderMode>();
-		auto& blitter = renderMode.blitter;
-
-		auto& transform = this->getComponent<pod::Transform<>>();
-		auto& scene = uf::scene::getCurrentScene();
-		auto& controller = *scene.getController();
-		auto& camera = this->getComponent<uf::Camera>();
-		auto& controllerCamera = controller.getComponent<uf::Camera>();
-		if ( !blitter.initialized ) return;
-
-		struct UniformDescriptor {
-			struct {
-				alignas(16) pod::Matrix4f models[2];
-			} matrices;
-			struct {
-				alignas(8) pod::Vector2f position = { 0.5f, 0.5f };
-				alignas(8) pod::Vector2f radius = { 0.1f, 0.1f };
-				alignas(16) pod::Vector4f color = { 1, 1, 1, 1 };
-			} cursor;
-			alignas(4) float alpha;
-		};
-
-		auto& shader = blitter.material.shaders.front();
-		auto& uniforms = shader.uniforms.front().get<UniformDescriptor>();
-
-		for ( std::size_t i = 0; i < 2; ++i ) {
-			pod::Matrix4f model = uf::transform::model( transform );
-
-			uniforms.matrices.models[i] = controllerCamera.getProjection(i) * controllerCamera.getView(i) * model;
-
-			uniforms.alpha = 1.0f;
-
-			uniforms.cursor.position.x = -1.0f;
-			uniforms.cursor.position.y = -1.0f;
-
-			uniforms.cursor.radius.x = 0.0f;
-			uniforms.cursor.radius.y = 0.0f;
-			
-			uniforms.cursor.color.x = 0.0f;
-			uniforms.cursor.color.y = 0.0f;
-			uniforms.cursor.color.z = 0.0f;
-			uniforms.cursor.color.w = 0.0f;
-		}
-		shader.updateBuffer( (void*) &uniforms, sizeof(uniforms), 0 );
-	}
-*/
 }
 void ext::Light::destroy() {
-	auto& renderMode = this->getComponent<ext::vulkan::RenderTargetRenderMode>();
-	ext::vulkan::removeRenderMode( &renderMode, false );
+	if ( this->hasComponent<ext::vulkan::RenderTargetRenderMode>() ) {
+		auto& renderMode = this->getComponent<ext::vulkan::RenderTargetRenderMode>();
+		ext::vulkan::removeRenderMode( &renderMode, false );
+	}
 	uf::Object::destroy();
 }
\ No newline at end of file
diff --git a/ext/scenes/world/player/hands.cpp b/ext/scenes/world/player/hands.cpp
index 5e79d6b5..eedce6ef 100644
--- a/ext/scenes/world/player/hands.cpp
+++ b/ext/scenes/world/player/hands.cpp
@@ -17,12 +17,11 @@
 namespace {
 	struct {
 		uf::Object left, right;
-	} hands;
-
-
+	} hands, lines;
 	struct {
-		uf::Object left, right;
-	} lines;
+		uf::Object* left;
+		uf::Object* right;
+	} lights;
 }
 
 EXT_OBJECT_REGISTER_CPP(Hands)
@@ -35,8 +34,8 @@ void ext::Hands::initialize() {
 		this->addChild(::hands.left);
 		this->addChild(::hands.right);
 
-		this->addChild(::lines.left);
-		this->addChild(::lines.right);
+		::hands.left.addChild(::lines.left);
+		::hands.right.addChild(::lines.right);
 	}
 	{
 		bool loaded = true;
@@ -49,48 +48,51 @@ void ext::Hands::initialize() {
 				uf::Serializer json = event;
 
 				std::string name = json["name"].asString();
-				uf::Object* pointer = NULL;
-				if ( name == metadata["hands"]["left"]["controller"]["model"].asString() ) pointer = &hands.left;
-				else if ( name == metadata["hands"]["right"]["controller"]["model"].asString() ) pointer = &hands.right;
-				else return "false";
+				std::string side = "";
+				if ( name == metadata["hands"]["left"]["controller"]["model"].asString() ) {
+					side = "left";
+				} else if ( name == metadata["hands"]["right"]["controller"]["model"].asString() ) {
+					side = "right";
+				};
+				if ( side == "" ) return "false";
 
+				uf::Object& hand = side == "left" ? hands.left : hands.right;
+				uf::Object& line = side == "left" ? lines.left : lines.right;
 				{
-					uf::Object& hand = *pointer;
 					uf::Graphic& graphic = (hand.getComponent<uf::Graphic>() = ext::openvr::getRenderModel( name ));
 					
 					graphic.process = true;
 
+					graphic.descriptor.frontFace = VK_FRONT_FACE_COUNTER_CLOCKWISE;
 					graphic.material.attachShader("./data/shaders/base.stereo.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
 					graphic.material.attachShader("./data/shaders/base.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
 
 					hand.initialize();
 				}
-				{
-					std::string hand = pointer == &hands.left ? "left" : "right";
-					auto& line = pointer == &hands.left ? lines.left : lines.right;
+				if ( metadata["hands"][side]["pointer"]["length"].asFloat() > 0 ) {
 					line.addAlias<uf::LineMesh, uf::Mesh>();
 
 					pod::Transform<>& transform = line.getComponent<pod::Transform<>>();
 					transform.orientation = uf::quaternion::axisAngle( 
 						{
-							metadata["hands"][hand]["pointer"]["orientation"]["axis"][0].asFloat(),
-							metadata["hands"][hand]["pointer"]["orientation"]["axis"][1].asFloat(),
-							metadata["hands"][hand]["pointer"]["orientation"]["axis"][2].asFloat()
+							metadata["hands"][side]["pointer"]["orientation"]["axis"][0].asFloat(),
+							metadata["hands"][side]["pointer"]["orientation"]["axis"][1].asFloat(),
+							metadata["hands"][side]["pointer"]["orientation"]["axis"][2].asFloat()
 						},
-						metadata["hands"][hand]["pointer"]["orientation"]["angle"].asFloat() * 3.14159f / 180.0f
+						metadata["hands"][side]["pointer"]["orientation"]["angle"].asFloat() * 3.14159f / 180.0f
 					);
 					transform.position = {
-						metadata["hands"][hand]["pointer"]["offset"][0].asFloat(),
-						metadata["hands"][hand]["pointer"]["offset"][1].asFloat(),
-						metadata["hands"][hand]["pointer"]["offset"][2].asFloat()
+						metadata["hands"][side]["pointer"]["offset"][0].asFloat(),
+						metadata["hands"][side]["pointer"]["offset"][1].asFloat(),
+						metadata["hands"][side]["pointer"]["offset"][2].asFloat()
 					};
 
 					auto& mesh = line.getComponent<uf::LineMesh>();
 					auto& graphic = line.getComponent<uf::Graphic>();
 
 					mesh.vertices = {
-						{ {0.0f, 0.0f,    0.0f} },
-						{ {0.0f, 0.0f, metadata["hands"][hand]["pointer"]["length"].asFloat()} },
+						{ {0.0f, 0.0f, 0.0f} },
+						{ {0.0f, 0.0f, metadata["hands"][side]["pointer"]["length"].asFloat()} },
 					};
 					graphic.initialize();
 					graphic.initializeGeometry(mesh);
@@ -99,27 +101,31 @@ void ext::Hands::initialize() {
 					graphic.material.attachShader("./data/shaders/line.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
 					graphic.descriptor.topology = VK_PRIMITIVE_TOPOLOGY_LINE_STRIP;
 					graphic.descriptor.fill = VK_POLYGON_MODE_LINE;
-					graphic.descriptor.lineWidth = metadata["hands"][hand]["pointer"]["width"].asFloat();
-				/*
-					graphic.initializeShaders({
-						{"./data/shaders/line.stereo.vert.spv", VK_SHADER_STAGE_VERTEX_BIT},
-						{"./data/shaders/line.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT}
-					});
-					mesh.generate();
-					graphic.bindUniform<uf::StereoMeshDescriptor>();
-					graphic.description.rasterMode.topology = VK_PRIMITIVE_TOPOLOGY_LINE_STRIP;
-					graphic.description.rasterMode.fill = VK_POLYGON_MODE_LINE;
-					graphic.description.rasterMode.lineWidth = metadata["hands"][hand]["pointer"]["width"].asFloat();
-					graphic.initialize();
-					graphic.autoAssign();
-				*/
+					graphic.descriptor.lineWidth = metadata["hands"][side]["pointer"]["width"].asFloat();
+
 					line.initialize();
 				}
+				if ( metadata["hands"][side]["light"]["should"].asBool() ){
+					auto* child = (uf::Object*) hand.findByUid(hand.loadChild("/light.json", false));
+					if ( child ) {
+						if (side == "left" ) lights.left = child; else lights.right = child;
+						auto& json = metadata["hands"][side]["light"];
+						auto& light = side == "left" ? *lights.left : *lights.right;
+
+						auto& metadata = light.getComponent<uf::Serializer>();
+						if ( !json["color"].isNull() ) metadata["light"]["color"] = json["color"];
+						if ( !json["radius"].isNull() ) metadata["light"]["radius"] = json["radius"];
+						if ( !json["power"].isNull() ) metadata["light"]["power"] = json["power"];
+						if ( !json["shadows"].isNull() ) metadata["light"]["shadows"] = json["shadows"];
+						metadata["lights"]["external update"] = true;
+
+						light.initialize();
+					}
+				}
 
 				return "true";
 			});
 		}
-
 		std::vector<uf::Object*> vHands = { &::hands.left, &::hands.right };
 		for ( auto pointer : vHands ) {
 			auto& hand = *pointer;
@@ -142,12 +148,34 @@ void ext::Hands::initialize() {
 					payload["mouse"]["button"] 			= side == "left" ? "Right" : "Left";
 					payload["mouse"]["state"] = json["state"].asBool() ? "Down": "Up";
 
-
 					uf::hooks.call( payload["type"].asString(), payload );
 				}
 
 				return "true";
 			});
+			hand.addHook("world:Collision.%UID%", [&](const std::string& event)->std::string{
+				uf::Serializer json = event;
+	
+				std::string side = &hand == &hands.left ? "left" : "right";
+
+				float mag = json["depth"].asFloat();
+				uf::Serializer payload;
+				payload["delay"] = 0.0f;
+				payload["duration"] = uf::physics::time::delta;
+				payload["frequency"] = 1.0f;
+				payload["amplitude"] = fmin(1.0f, 1000.0f * mag);
+				payload["side"] = side;
+				uf::hooks.call( "VR:Haptics." + side, payload );
+
+				return "true";
+			});
+
+			auto& transform = hand.getComponent<pod::Transform<>>();
+			auto& collider = hand.getComponent<uf::Collider>();
+
+		//	auto* box = new uf::BoundingBox( transform.position, {0.25, 0.25, 0.25} );
+		//	box->getTransform().reference = &transform;
+		//	collider.add(box);
 		}
 	}
 }
@@ -155,26 +183,58 @@ void ext::Hands::tick() {
 	uf::Object::tick();
 	auto& scene = uf::scene::getCurrentScene();
 	auto& controller = *scene.getController();
-	auto& camera = controller.getComponent<uf::Camera>();
+	auto& controllerCamera = controller.getComponent<uf::Camera>();
+	auto& controllerTransform = controller.getComponent<pod::Transform<>>();
+	auto& controllerCameraTransform = controllerCamera.getTransform();
 	{
 		pod::Transform<>& transform = hands.left.getComponent<pod::Transform<>>();
 		transform.position = ext::openvr::controllerPosition( vr::Controller_Hand::Hand_Left );
 		transform.orientation = ext::openvr::controllerQuaternion( vr::Controller_Hand::Hand_Left );
 		transform.scale = { 1, 1, 1 };
-		// transform.reference = &camera.getTransform();
+		transform.reference = &controllerTransform;
+
+		auto& collider = hands.left.getComponent<uf::Collider>();
+		for ( auto* box : collider.getContainer() ) {
+			box->getTransform().position = transform.position + controllerTransform.position + controllerCameraTransform.position;
+		}
 	}
 	{
 		pod::Transform<>& transform = hands.right.getComponent<pod::Transform<>>();
 		transform.position = ext::openvr::controllerPosition( vr::Controller_Hand::Hand_Right );
 		transform.orientation = ext::openvr::controllerQuaternion( vr::Controller_Hand::Hand_Right );
 		transform.scale = { 1, 1, 1 };
-		// transform.reference = &camera.getTransform();
+		transform.reference = &controllerTransform;
+
+		auto& collider = hands.right.getComponent<uf::Collider>();
+		for ( auto* box : collider.getContainer() ) {
+			box->getTransform().position = transform.position + controllerTransform.position + controllerCameraTransform.position;
+		}
 	}
 	{
 		pod::Transform<>& transform = lines.left.getComponent<pod::Transform<>>();
 		transform.position = ext::openvr::controllerPosition( vr::Controller_Hand::Hand_Left, true );
 		transform.orientation = ext::openvr::controllerQuaternion( vr::Controller_Hand::Hand_Left, true );
 		transform.scale = { 1, 1, 1 };
+		transform.reference = &controllerTransform;
+
+		if ( lights.left ) {
+			auto& light = *lights.left;
+			auto& lightTransform = light.getComponent<pod::Transform<>>();
+			lightTransform.position = controllerCameraTransform.position + controller.getComponent<pod::Transform<>>().position + transform.position;
+		//	lightTransform.orientation = controllerTransform.orientation * transform.orientation;
+			auto& lightCamera = light.getComponent<uf::Camera>();
+			pod::Matrix4f playerModel = uf::matrix::identity();
+			pod::Matrix4f translation = uf::matrix::translate( uf::matrix::identity(), controllerCameraTransform.position + controllerTransform.position );
+			pod::Matrix4f rotation = uf::quaternion::matrix( controllerTransform.orientation * pod::Vector4f{1,1,1,-1} );
+			playerModel = translation * rotation;
+
+			pod::Matrix4f model = uf::matrix::inverse( playerModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Left, true ) );
+			for ( size_t i = 0; i < 2; ++i ) lightCamera.setView( model, i );
+		
+		//	lightTransform.position = transform.position;
+		//	lightTransform.orientation = transform.orientation;
+		//	lightTransform.reference = &controllerTransform;
+		}
 		// transform.reference = hands.left.getComponentPointer<pod::Transform<>>();
 	}
 	{
@@ -182,6 +242,26 @@ void ext::Hands::tick() {
 		transform.position = ext::openvr::controllerPosition( vr::Controller_Hand::Hand_Right, true );
 		transform.orientation = ext::openvr::controllerQuaternion( vr::Controller_Hand::Hand_Right, true );
 		transform.scale = { 1, 1, 1 };
+		transform.reference = &controllerTransform;
+
+		if ( lights.right ) {
+			auto& light = *lights.right;
+			auto& lightTransform = light.getComponent<pod::Transform<>>();
+			lightTransform.position = controllerCameraTransform.position + controllerTransform.position + transform.position;
+		//	lightTransform.orientation = controllerTransform.orientation * transform.orientation;
+			auto& lightCamera = light.getComponent<uf::Camera>();
+			pod::Matrix4f playerModel = uf::matrix::identity();
+			pod::Matrix4f translation = uf::matrix::translate( uf::matrix::identity(), controllerCameraTransform.position + controllerTransform.position );
+			pod::Matrix4f rotation = uf::quaternion::matrix( controllerTransform.orientation * pod::Vector4f{1,1,1,-1} );
+			playerModel = translation * rotation;
+
+			pod::Matrix4f model = uf::matrix::inverse( playerModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Right, true ) );
+			for ( size_t i = 0; i < 2; ++i ) lightCamera.setView( model, i );
+		
+		//	lightTransform.position = transform.position;
+		//	lightTransform.orientation = transform.orientation;
+		//	lightTransform.reference = &controllerTransform;
+		}
 		// transform.reference = hands.right.getComponentPointer<pod::Transform<>>();
 	}
 
@@ -256,9 +336,7 @@ void ext::Hands::tick() {
 					}
 				}
 			}
-
-			#define DEBUG_MARKER() std::cout << side << ": " << __LINE__ << std::endl;
-
+		#if 0
 			/* Collision against world */ {
 				bool local = true;
 				bool sort = false;
@@ -271,7 +349,7 @@ void ext::Hands::tick() {
 					pod::Transform<> transform = hand.getComponent<pod::Transform<>>();
 					transform.position = uf::quaternion::rotate( controller.getComponent<pod::Transform<>>().orientation, transform.position );
 					transform.position += controller.getComponent<pod::Transform<>>().position;
-					transform.position += camera.getTransform().position;
+					transform.position += controllerCamera.getTransform().position;
 
 					uf::Entity& parent = controller.getParent();
 					ext::TerrainGenerator& generator = parent.getComponent<ext::TerrainGenerator>();
@@ -319,13 +397,13 @@ void ext::Hands::tick() {
 
 						if ( !voxel.solid() ) continue;
 
-						uf::Collider* box = new uf::AABBox( offset, {0.5, 0.5, 0.5} );
+						uf::Collider* box = new uf::BoundingBox( offset, {0.5, 0.5, 0.5} );
 						pCollider.add(box);
 					}
 					
 					uf::CollisionBody& collider = hand.getComponent<uf::CollisionBody>(); {
 						collider.clear();
-						uf::Collider* box = new uf::AABBox( transform.position, {0.25, 0.25, 0.25} );
+						uf::Collider* box = new uf::BoundingBox( transform.position, {0.25, 0.25, 0.25} );
 						collider.add(box);
 					}
 					
@@ -351,17 +429,12 @@ void ext::Hands::tick() {
 							payload["side"] = side;
 							uf::hooks.call( "VR:Haptics." + side, payload );
 						}
-					/*
-						transform.position += correction;
-						if ( strongest.normal.x == 1 || strongest.normal.x == -1 ) physics.linear.velocity.x = 0;
-						if ( strongest.normal.y == 1 || strongest.normal.y == -1 ) physics.linear.velocity.y = 0;
-						if ( strongest.normal.z == 1 || strongest.normal.z == -1 ) physics.linear.velocity.z = 0;
-					*/
 					}
 					return 0;
 				};
 				if ( local ) function(); else uf::thread::add( thread, function, true );
 			}
+		#endif
 		}
 	}
 }
@@ -373,13 +446,19 @@ void ext::Hands::render() {
 	auto& controller = *scene.getController();
 	auto& camera = controller.getComponent<uf::Camera>();
 
-	pod::Matrix4f cameraModel = uf::matrix::translate( uf::matrix::identity(), camera.getTransform().position + controller.getComponent<pod::Transform<>>().position ) * uf::quaternion::matrix( controller.getComponent<pod::Transform<>>().orientation * pod::Vector4f{1,1,1,-1} );
-	if ( hands.left.hasComponent<uf::Mesh>() ) {
-		auto& mesh = hands.left.getComponent<uf::Mesh>();
+	pod::Matrix4f playerModel = uf::matrix::identity(); {
+		auto& controller = this->getParent();
+		auto& camera = controller.getComponent<uf::Camera>();
+		pod::Matrix4f translation = uf::matrix::translate( uf::matrix::identity(), camera.getTransform().position + controller.getComponent<pod::Transform<>>().position );
+		pod::Matrix4f rotation = uf::quaternion::matrix( controller.getComponent<pod::Transform<>>().orientation * pod::Vector4f{1,1,1,-1} );
+		playerModel = translation * rotation;
+	}
+//	pod::Matrix4f cameraModel = uf::matrix::translate( uf::matrix::identity(), camera.getTransform().position + controller.getComponent<pod::Transform<>>().position ) * uf::quaternion::matrix( controller.getComponent<pod::Transform<>>().orientation * pod::Vector4f{1,1,1,-1} );	
+	if ( hands.left.hasComponent<uf::Graphic>() ) {
 		auto& graphic = hands.left.getComponent<uf::Graphic>();
 		auto& transform = hands.left.getComponent<pod::Transform<>>();
 		graphic.process = ext::openvr::controllerActive( vr::Controller_Hand::Hand_Left );
-		pod::Matrix4f model = cameraModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Left, false );
+		pod::Matrix4f model = playerModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Left, false );
 		if ( graphic.initialized ) {	
 			// auto& uniforms = graphic.uniforms<uf::StereoMeshDescriptor>();
 			auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
@@ -396,12 +475,11 @@ void ext::Hands::render() {
 			graphic.material.shaders.front().updateBuffer( uniforms, 0, false );
 		}
 	}
-	if ( hands.right.hasComponent<uf::Mesh>() ) {
-		auto& mesh = hands.right.getComponent<uf::Mesh>();
+	if ( hands.right.hasComponent<uf::Graphic>() ) {
 		auto& graphic = hands.right.getComponent<uf::Graphic>();
 		auto& transform = hands.right.getComponent<pod::Transform<>>();
 		graphic.process = ext::openvr::controllerActive( vr::Controller_Hand::Hand_Right );
-		pod::Matrix4f model = cameraModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Right, false );
+		pod::Matrix4f model = playerModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Right, false );
 		if ( graphic.initialized ) {	
 			// auto& uniforms = graphic.uniforms<uf::StereoMeshDescriptor>();
 			auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
@@ -418,12 +496,11 @@ void ext::Hands::render() {
 			graphic.material.shaders.front().updateBuffer( uniforms, 0, false );
 		}
 	}
-	if ( lines.left.hasComponent<uf::Mesh>() ) {
-		auto& mesh = lines.left.getComponent<uf::Mesh>();
+	if ( lines.left.hasComponent<uf::Graphic>() ) {
 		auto& graphic = lines.left.getComponent<uf::Graphic>();
 		auto& transform = lines.left.getComponent<pod::Transform<>>();
 		graphic.process = ext::openvr::controllerActive( vr::Controller_Hand::Hand_Left );
-		pod::Matrix4f model = cameraModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Left, true );
+		pod::Matrix4f model = playerModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Left, true );
 		if ( graphic.initialized ) {	
 			// auto& uniforms = graphic.uniforms<uf::StereoMeshDescriptor>();
 			auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
@@ -440,12 +517,11 @@ void ext::Hands::render() {
 			graphic.material.shaders.front().updateBuffer( uniforms, 0, false );
 		}
 	}
-	if ( lines.right.hasComponent<uf::Mesh>() ) {
-		auto& mesh = lines.right.getComponent<uf::Mesh>();
+	if ( lines.right.hasComponent<uf::Graphic>() ) {
 		auto& graphic = lines.right.getComponent<uf::Graphic>();
 		auto& transform = lines.right.getComponent<pod::Transform<>>();
 		graphic.process = ext::openvr::controllerActive( vr::Controller_Hand::Hand_Right );
-		pod::Matrix4f model = cameraModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Right, true );
+		pod::Matrix4f model = playerModel * ext::openvr::controllerModelMatrix( vr::Controller_Hand::Hand_Right, true );
 		if ( graphic.initialized ) {	
 			// auto& uniforms = graphic.uniforms<uf::StereoMeshDescriptor>();
 			auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
diff --git a/ext/scenes/world/player/player.cpp b/ext/scenes/world/player/player.cpp
index 91b6136a..aa1b7899 100644
--- a/ext/scenes/world/player/player.cpp
+++ b/ext/scenes/world/player/player.cpp
@@ -63,6 +63,7 @@ void ext::Player::initialize() {
 				pod::Vector2 bounds = {0.5, 128.0};
 			} perspective;
 			pod::Vector3 offset = {0, 0, 0};
+			bool stereoscopic = true;
 		} settings;
 
 		uf::Camera& camera = this->getComponent<uf::Camera>();
@@ -86,8 +87,8 @@ void ext::Player::initialize() {
 
 			camera.setFov(settings.perspective.fov);
 			camera.setBounds(settings.perspective.bounds);
-	
 		}
+		camera.setStereoscopic(true);
 
 		settings.offset.x = metadata["camera"]["offset"][0].asDouble();
 		settings.offset.y = metadata["camera"]["offset"][1].asDouble();
@@ -98,6 +99,10 @@ void ext::Player::initialize() {
 			transform.position.x = metadata["camera"]["position"][0].asDouble();
 			transform.position.y = metadata["camera"]["position"][1].asDouble();
 			transform.position.z = metadata["camera"]["position"][2].asDouble();
+
+			transform.scale.x = metadata["camera"]["scale"][0].asDouble();
+			transform.scale.y = metadata["camera"]["scale"][1].asDouble();
+			transform.scale.z = metadata["camera"]["scale"][2].asDouble();
 		}
 
 		camera.setOffset(settings.offset);
@@ -318,14 +323,17 @@ void ext::Player::tick() {
 	if ( ext::openvr::context ) {
 		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "dpadUp" )["state"].asBool() ) keys.forward = true;
 		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "dpadDown" )["state"].asBool() ) keys.backwards = true;
-		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "dpadLeft" )["state"].asBool() ) keys.lookLeft = true; //keys.left = true;
-		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "dpadRight" )["state"].asBool() ) keys.lookRight = true; //keys.right = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "dpadLeft" )["state"].asBool() ) keys.left = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "dpadRight" )["state"].asBool() ) keys.right = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "thumbclick" )["state"].asBool() ) keys.running = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Right, "a" )["state"].asBool() ) keys.jump = true;
 
-	//	if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "dpadUp" )["state"].asBool() ) keys.forward = true;
-	//	if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "dpadDown" )["state"].asBool() ) keys.backwards = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "dpadUp" )["state"].asBool() ) keys.forward = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "dpadDown" )["state"].asBool() ) keys.backwards = true;
 		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "dpadLeft" )["state"].asBool() ) keys.lookLeft = true;
 		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "dpadRight" )["state"].asBool() ) keys.lookRight = true;
-	//	std::cout << ext::openvr::controllerState( vr::Controller_Hand::Hand_Right ) << std::endl;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "thumbclick" )["state"].asBool() ) keys.crouch = true, keys.walk = true;
+		if ( ext::openvr::controllerState( vr::Controller_Hand::Hand_Left, "a" )["state"].asBool() ) keys.paused = true;
 	}
 	
 	struct {
@@ -339,22 +347,32 @@ void ext::Player::tick() {
 	stats.menu = metadata["system"]["menu"].asString();
 
 	struct {
-		float move = 4; //uf::physics::time::delta * 4;
-		float rotate = uf::physics::time::delta * 1.25f;
+		float move = 4;
+		float walk = 1;
+		float run = 8;
+		float rotate = uf::physics::time::delta;
 		float limitSquared = 4*4;
-	} speed;
+	} speed; {
+		speed.rotate *= metadata["system"]["physics"]["rotate"].asFloat();
+		speed.move = metadata["system"]["physics"]["move"].asFloat();
+		speed.run = metadata["system"]["physics"]["run"].asFloat() / metadata["system"]["physics"]["move"].asFloat();
+		speed.walk = metadata["system"]["physics"]["walk"].asFloat() / metadata["system"]["physics"]["move"].asFloat();
+	}
+
+
+
 	static uf::Timer<long long> timer(false);
 	if ( !timer.running() ) timer.start();
 	if ( keys.vee ) {
 		if ( timer.elapsed().asDouble() >= 0.25 ) {
 			timer.reset();
-			metadata["collision"]["should"] = !metadata["collision"]["should"].asBool();
+			metadata["system"]["physics"]["collision"] = !metadata["system"]["physics"]["collision"].asBool();
 
 			physics.linear.velocity = {0,0,0};
 		}
 	}
-	if ( keys.running ) speed.move *= 2;
-	else if ( keys.walk ) speed.move /= 4;
+	if ( keys.running ) speed.move *= speed.run;
+	else if ( keys.walk ) speed.move *= speed.walk;
 	speed.limitSquared = speed.move * speed.move;
 
 	uf::Object* menu = (uf::Object*) this->getRootParent().findByName("Gui: Menu");
@@ -382,7 +400,7 @@ void ext::Player::tick() {
 			//	translator.orientation = uf::quaternion::multiply( transform.orientation * pod::Vector4f{1,1,1,-1}, ext::openvr::hmdQuaternion() * pod::Vector4f{1,1,1,-1} );
 			//	translator.orientation = uf::quaternion::multiply( ext::openvr::hmdQuaternion(), transform.orientation );
 				//translator.orientation = ext::openvr::hmdQuaternion();
-				bool useController = true;
+				bool useController = false;
 				translator.orientation = uf::quaternion::multiply( transform.orientation * pod::Vector4f{1,1,1,1}, useController ? (ext::openvr::controllerQuaternion( vr::Controller_Hand::Hand_Right ) * pod::Vector4f{1,1,1,-1}) : ext::openvr::hmdQuaternion() );
 				translator = uf::transform::reorient( translator );
 				{
@@ -437,15 +455,15 @@ void ext::Player::tick() {
 				physics.linear.velocity.z = correction.z;
 				stats.updateCamera = (stats.walking = true);
 			}
-			if ( keys.jump && metadata["collision"]["jump"] != Json::nullValue ) {
-				if ( !metadata["collision"]["should"].asBool() ) {
-					if ( metadata["collision"]["jump"][0].asFloat() != 0 ) transform.position.x += metadata["collision"]["jump"][0].asFloat() * uf::physics::time::delta;
-					if ( metadata["collision"]["jump"][1].asFloat() != 0 ) transform.position.y += metadata["collision"]["jump"][1].asFloat() * uf::physics::time::delta;
-					if ( metadata["collision"]["jump"][2].asFloat() != 0 ) transform.position.z += metadata["collision"]["jump"][2].asFloat() * uf::physics::time::delta;
+			if ( keys.jump ) {
+				if ( !metadata["system"]["physics"]["collision"].asBool() ) {
+					if ( metadata["system"]["physics"]["jump"][0].asFloat() != 0 ) transform.position.x += metadata["system"]["physics"]["jump"][0].asFloat() * uf::physics::time::delta;
+					if ( metadata["system"]["physics"]["jump"][1].asFloat() != 0 ) transform.position.y += metadata["system"]["physics"]["jump"][1].asFloat() * uf::physics::time::delta;
+					if ( metadata["system"]["physics"]["jump"][2].asFloat() != 0 ) transform.position.z += metadata["system"]["physics"]["jump"][2].asFloat() * uf::physics::time::delta;
 				} else {
-					if ( metadata["collision"]["jump"][0].asFloat() != 0 ) physics.linear.velocity.x = metadata["collision"]["jump"][0].asFloat();
-					if ( metadata["collision"]["jump"][1].asFloat() != 0 ) physics.linear.velocity.y = metadata["collision"]["jump"][1].asFloat();
-					if ( metadata["collision"]["jump"][2].asFloat() != 0 ) physics.linear.velocity.z = metadata["collision"]["jump"][2].asFloat();
+					if ( metadata["system"]["physics"]["jump"][0].asFloat() != 0 ) physics.linear.velocity.x = metadata["system"]["physics"]["jump"][0].asFloat();
+					if ( metadata["system"]["physics"]["jump"][1].asFloat() != 0 ) physics.linear.velocity.y = metadata["system"]["physics"]["jump"][1].asFloat();
+					if ( metadata["system"]["physics"]["jump"][2].asFloat() != 0 ) physics.linear.velocity.z = metadata["system"]["physics"]["jump"][2].asFloat();
 				}
 			}
 		}
@@ -458,10 +476,10 @@ void ext::Player::tick() {
 		}
 		
 		if ( keys.crouch ) {
-			if ( !metadata["collision"]["should"].asBool() ) {
-				if ( metadata["collision"]["jump"][0].asFloat() != 0 ) transform.position.x -= metadata["collision"]["jump"][0].asFloat() * uf::physics::time::delta;
-				if ( metadata["collision"]["jump"][1].asFloat() != 0 ) transform.position.y -= metadata["collision"]["jump"][1].asFloat() * uf::physics::time::delta;
-				if ( metadata["collision"]["jump"][2].asFloat() != 0 ) transform.position.z -= metadata["collision"]["jump"][2].asFloat() * uf::physics::time::delta;
+			if ( !metadata["system"]["physics"]["collision"].asBool() ) {
+				if ( metadata["system"]["physics"]["jump"][0].asFloat() != 0 ) transform.position.x -= metadata["system"]["physics"]["jump"][0].asFloat() * uf::physics::time::delta;
+				if ( metadata["system"]["physics"]["jump"][1].asFloat() != 0 ) transform.position.y -= metadata["system"]["physics"]["jump"][1].asFloat() * uf::physics::time::delta;
+				if ( metadata["system"]["physics"]["jump"][2].asFloat() != 0 ) transform.position.z -= metadata["system"]["physics"]["jump"][2].asFloat() * uf::physics::time::delta;
 			} else {
 				if ( !metadata["system"]["crouching"].asBool() )  stats.deltaCrouch = true;
 				metadata["system"]["crouching"] = true;
@@ -472,7 +490,7 @@ void ext::Player::tick() {
 		}	
 	}
 	if ( stats.deltaCrouch ) {
-		float delta = 1.0f;
+		float delta = metadata["system"]["physics"]["crouch"].asFloat();
 		if ( metadata["system"]["crouching"].asBool() ) camera.getTransform().position.y -= delta;
 		else camera.getTransform().position.y += delta;
 		stats.updateCamera = true;
@@ -495,7 +513,7 @@ void ext::Player::tick() {
 				footstep.setVolume(0.1f);
 				footstep.setPosition( transform.position );
 			}
-		} else {
+		} else if ( !keys.jump ) {
 			physics.linear.velocity.x = 0;
 			physics.linear.velocity.y = 0;
 			physics.linear.velocity.z = 0;
diff --git a/ext/scenes/world/terrain/region.cpp b/ext/scenes/world/terrain/region.cpp
index aa0e8f72..cc50620a 100644
--- a/ext/scenes/world/terrain/region.cpp
+++ b/ext/scenes/world/terrain/region.cpp
@@ -6,6 +6,7 @@
 #include "..//sprite.h"
 #include <uf/engine/asset/asset.h>
 #include <uf/utils/camera/camera.h>
+#include <uf/utils/thread/thread.h>
 #include <uf/utils/math/collision.h>
 #include <uf/utils/graphic/graphic.h>
 #include <uf/utils/graphic/mesh.h>
@@ -54,7 +55,8 @@ void ext::Region::initialize() {
 		graphic.process = false;
 
 		auto& texture = graphic.material.textures.emplace_back();
-		texture.sampler.filter = VK_FILTER_NEAREST;
+		texture.sampler.descriptor.filter.min = VK_FILTER_NEAREST;
+		texture.sampler.descriptor.filter.mag = VK_FILTER_NEAREST;
 		texture.loadFromFile( textureFilename );
 
 		std::string suffix = ""; {
@@ -83,9 +85,9 @@ void ext::Region::initialize() {
 		generator.generate(*this);
 		generator.updateLight();
 
-		/* Collider */ {
+		/* Collider */ if ( false ) {
 			pod::Transform<>& transform = this->getComponent<pod::Transform<>>();
-			uf::CollisionBody& collider = this->getComponent<uf::CollisionBody>();
+			uf::Collider& collider = this->getComponent<uf::Collider>();
 		
 			std::size_t i = 0;
 			const auto& voxels = generator.getVoxels();
@@ -108,8 +110,7 @@ void ext::Region::initialize() {
 
 						if ( !voxel.solid() ) continue;
 
-						uf::Collider* box = new uf::AABBox( offset, {0.5, 0.5, 0.5} );
-						collider.add(box);
+						collider.add(new uf::BoundingBox( offset, {0.5, 0.5, 0.5} ));
 					}
 				}
 			}
@@ -200,12 +201,16 @@ void ext::Region::initialize() {
 			}
 			if ( should ) {
 				uf::Entity* light = this->findByUid(this->loadChild("./light.json", true));
-				uf::Serializer& metadata = light->getComponent<uf::Serializer>();
-				pod::Transform<>& lTransform = light->getComponent<pod::Transform<>>();
-				lTransform.position = transform.position;
-				metadata["light"]["color"][0] = r;
-				metadata["light"]["color"][1] = r;
-				metadata["light"]["color"][2] = r;
+				if ( light ) {
+					uf::Serializer& metadata = light->getComponent<uf::Serializer>();
+					pod::Transform<>& lTransform = light->getComponent<pod::Transform<>>();
+					lTransform.position += transform.position;
+					if ( !metadata["light"].isArray() ) {
+						metadata["light"]["color"][0] = (rand() % 100) / 100.0;
+						metadata["light"]["color"][1] = (rand() % 100) / 100.0;
+						metadata["light"]["color"][2] = (rand() % 100) / 100.0;
+					}
+				}
 			}
 		}
 		// add mobs
@@ -273,6 +278,139 @@ void ext::Region::initialize() {
 }
 void ext::Region::tick() {
 	uf::Object::tick();
+
+	// do collision on children
+#if 1
+	{
+		bool local = false;
+		bool sort = false;
+		bool useStrongest = true;
+		pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+		auto function = [&]() -> int {
+			std::vector<uf::Object*> entities;
+			std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
+				auto& metadata = entity->getComponent<uf::Serializer>();
+				if ( !metadata["system"]["physics"]["collision"].isNull() && !metadata["system"]["physics"]["collision"].asBool() ) return;
+				if ( entity->hasComponent<uf::Collider>() )
+					entities.push_back((uf::Object*) entity);
+			};
+			this->process(filter);
+			auto onCollision = []( pod::Collider::Manifold& manifold, uf::Object* a, uf::Object* b ){				
+				uf::Serializer payload;
+				payload["normal"][0] = manifold.normal.x;
+				payload["normal"][1] = manifold.normal.y;
+				payload["normal"][2] = manifold.normal.z;
+				payload["entity"] = b->getUid();
+				payload["depth"] = -manifold.depth;
+				a->callHook("world:Collision.%UID%", payload);
+				
+				payload["entity"] = a->getUid();
+				payload["depth"] = manifold.depth;
+				b->callHook("world:Collision.%UID%", payload);
+			/*
+				pod::Transform<>& transform = b->getComponent<pod::Transform<>>();
+				pod::Physics& physics = b->getComponent<pod::Physics>();
+
+				uf::Serializer payload;
+				pod::Vector3 correction = uf::vector::normalize(manifold.normal) * manifold.depth;
+				transform.position -= correction;
+
+				if ( manifold.normal.x == 1 || manifold.normal.x == -1 ) physics.linear.velocity.x = 0;
+				if ( manifold.normal.y == 1 || manifold.normal.y == -1 ) physics.linear.velocity.y = 0;
+				if ( manifold.normal.z == 1 || manifold.normal.z == -1 ) physics.linear.velocity.z = 0;
+			*/
+			};
+			auto testColliders = [&]( uf::Collider& colliderA, uf::Collider& colliderB, uf::Object* a, uf::Object* b, bool useStrongest ){
+				pod::Collider::Manifold strongest;
+				auto manifolds = colliderA.intersects(colliderB);
+				for ( auto manifold : manifolds ) {
+					if ( manifold.colliding && manifold.depth > 0 ) {
+						if ( !useStrongest ) onCollision(manifold, a, b);
+						else if ( strongest.depth < manifold.depth ) strongest = manifold;
+					}
+				}
+				if ( useStrongest && strongest.colliding ) onCollision(strongest, a, b);
+			};
+
+			// collide with world
+			auto& metadata = this->getComponent<uf::Serializer>();
+			auto& generator = this->getComponent<ext::TerrainGenerator>();
+			auto& regionPosition = this->getComponent<pod::Transform<>>().position;
+			pod::Vector3f size; {
+				size.x = metadata["region"]["size"][0].asUInt();
+				size.y = metadata["region"]["size"][1].asUInt();
+				size.z = metadata["region"]["size"][2].asUInt();
+			}
+			for ( auto* _ : entities ) {
+				uf::Object& entity = *_;
+				auto& transform = entity.getComponent<pod::Transform<>>();
+
+			
+				pod::Vector3f voxelPosition = transform.position - regionPosition;
+				voxelPosition.x += size.x / 2.0f;
+				voxelPosition.y += size.y / 2.0f + 1;
+				voxelPosition.z += size.z / 2.0f;
+
+				uf::Collider collider;
+				std::vector<pod::Vector3ui> positions = {
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x - 1, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x + 1, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y - 1, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y + 1, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z - 1 },
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z + 1},
+				};
+				for ( auto& position : positions ) {
+					ext::TerrainVoxel voxel = ext::TerrainVoxel::atlas( generator.getVoxel( position.x, position.y, position.z ) );
+					pod::Vector3 offset = regionPosition;
+					offset.x += position.x - (size.x / 2.0f);
+					offset.y += position.y - (size.y / 2.0f);
+					offset.z += position.z - (size.z / 2.0f);
+
+					if ( !voxel.solid() ) continue;
+
+					collider.add( new uf::BoundingBox( offset, {0.5, 0.5, 0.5} ) );
+				/*
+					uf::BaseMesh<pod::Vertex_3F> mesh;
+					const ext::TerrainVoxel::Model& model = voxel.model();
+					#define TERRAIN_SHOULD_RENDER_FACE(SIDE)\
+						for ( uint i = 0; i < model.position.SIDE.size() / 3; ++i ) {\
+							auto& vertex = mesh.vertices.emplace_back();\
+							{\
+								pod::Vector3f& p = vertex.position;\
+								p.x = model.position.SIDE[i*3+0]; p.y = model.position.SIDE[i*3+1]; p.z = model.position.SIDE[i*3+2];\
+								p.x += offset.x; p.y += offset.y; p.z += offset.z;\
+							}\
+						}
+					TERRAIN_SHOULD_RENDER_FACE(left)
+					TERRAIN_SHOULD_RENDER_FACE(right)
+					TERRAIN_SHOULD_RENDER_FACE(top)
+					TERRAIN_SHOULD_RENDER_FACE(bottom)
+					TERRAIN_SHOULD_RENDER_FACE(back)
+					TERRAIN_SHOULD_RENDER_FACE(front)
+					uf::MeshCollider* mCollider = new uf::MeshCollider();
+					mCollider->setPositions( mesh );
+					pCollider.add(mCollider);
+				*/
+				}
+				testColliders( collider, entity.getComponent<uf::Collider>(), this, &entity, useStrongest );
+			}
+		
+			// collide with others
+			for ( auto* _a : entities ) {
+				uf::Object& entityA = *_a;
+				for ( auto* _b : entities ) { if ( _a == _b ) continue;
+					uf::Object& entityB = *_b;
+					testColliders( entityA.getComponent<uf::Collider>(), entityB.getComponent<uf::Collider>(), &entityA, &entityB, useStrongest );
+				}
+			}
+		
+			return 0;
+		};
+		if ( local ) function(); else uf::thread::add( thread, function, true );
+	}
+#endif
 }
 void ext::Region::destroy() {
 	auto& graphic = this->getComponent<uf::Graphic>();
@@ -289,11 +427,11 @@ void ext::Region::render( ) {
 	uf::Object::render();
 
 	if ( !metadata["region"]["rasterized"].asBool() ) return;
-	/* Update uniforms */ if ( this->hasComponent<ext::TerrainGenerator::mesh_t>() ) {
-		auto& world = this->getRootParent<uf::Scene>();
+	/* Update uniforms */ if ( this->hasComponent<uf::Graphic>() ) {
+		auto& scene = this->getRootParent<uf::Scene>();
 		auto& mesh = this->getComponent<ext::TerrainGenerator::mesh_t>();
 		auto& graphic = this->getComponent<uf::Graphic>();
-		auto& camera = world.getController()->getComponent<uf::Camera>();		
+		auto& camera = scene.getController()->getComponent<uf::Camera>();		
 		if ( !graphic.initialized ) return;
 	//	auto& uniforms = graphic.uniforms<uf::StereoMeshDescriptor>();
 		auto& uniforms = graphic.material.shaders.front().uniforms.front().get<uf::StereoMeshDescriptor>();
diff --git a/ext/scenes/world/terrain/terrain.cpp b/ext/scenes/world/terrain/terrain.cpp
index 49615065..4dae8f19 100644
--- a/ext/scenes/world/terrain/terrain.cpp
+++ b/ext/scenes/world/terrain/terrain.cpp
@@ -1,4 +1,5 @@
 #include "terrain.h"
+#include "generator.h"
 
 #include "../../../ext.h"
 #include <uf/engine/asset/asset.h>
@@ -10,6 +11,7 @@
 #include <uf/utils/graphic/mesh.h>
 #include <uf/utils/graphic/graphic.h>
 #include <uf/utils/camera/camera.h>
+#include <uf/utils/math/collision.h>
 #include <uf/utils/thread/thread.h>
 #include <uf/ext/vulkan/graphic.h>
 #include <uf/ext/vulkan/vulkan.h>
@@ -145,7 +147,150 @@ void ext::Terrain::tick() {
 
 	// multipurpose timer
 	static uf::Timer<long long> timer(false);
+	// do collision on children
+#if 0
+	{
+		bool local = false;
+		bool sort = false;
+		bool useStrongest = false;
+		pod::Thread& thread = uf::thread::has("Physics") ? uf::thread::get("Physics") : uf::thread::create( "Physics", true, false );
+		auto function = [&]() -> int {
+			std::vector<uf::Object*> entities;
+			std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
+				auto& metadata = entity->getComponent<uf::Serializer>();
+				if ( !metadata["system"]["physics"]["collision"].isNull() && !metadata["system"]["physics"]["collision"].asBool() ) return;
+				if ( entity->hasComponent<uf::Collider>() )
+					entities.push_back((uf::Object*) entity);
+			};
+			this->process(filter);
+			auto onCollision = []( pod::Collider::Manifold& manifold, uf::Object* a, uf::Object* b ){				
+				uf::Serializer payload;
+				payload["normal"][0] = manifold.normal.x;
+				payload["normal"][1] = manifold.normal.y;
+				payload["normal"][2] = manifold.normal.z;
+				payload["entity"] = b->getUid();
+				payload["depth"] = -manifold.depth;
+				a->callHook("world:Collision.%UID%", payload);
+				
+				payload["entity"] = a->getUid();
+				payload["depth"] = manifold.depth;
+				b->callHook("world:Collision.%UID%", payload);
+			};
+			auto testColliders = [&]( uf::Collider& colliderA, uf::Collider& colliderB, uf::Object* a, uf::Object* b, bool useStrongest ){
+				pod::Collider::Manifold strongest;
+				auto manifolds = colliderA.intersects(colliderB);
+				for ( auto manifold : manifolds ) {
+					if ( manifold.colliding && manifold.depth > 0 ) {
+						if ( !useStrongest ) onCollision(manifold, a, b);
+						else if ( strongest.depth < manifold.depth ) strongest = manifold;
+					}
+				}
+				if ( useStrongest && strongest.colliding ) onCollision(strongest, a, b);
+			};
 
+			// collide with world
+			for ( auto* _ : entities ) {
+				uf::Object& entity = *_;
+				auto& transform = entity.getComponent<pod::Transform<>>();
+
+				pod::Vector3f size; {
+					size.x = metadata["region"]["size"][0].asUInt();
+					size.y = metadata["region"]["size"][1].asUInt();
+					size.z = metadata["region"]["size"][2].asUInt();
+				}
+				uf::Entity* regionPointer = _;
+				while ( regionPointer->getName() != "Region" ) {
+					regionPointer = &regionPointer->getParent();
+					if ( regionPointer->getUid() == 0 ) break;
+					if ( regionPointer->getUid() == this->getUid() ) break;
+				}
+				if ( regionPointer == this ) continue;
+				if ( regionPointer->getUid() == 0 ) continue;
+				if ( regionPointer->getName() != "Region" ) continue;
+				if ( !regionPointer ) continue;
+				ext::Region& region = *(ext::Region*) regionPointer;
+			/*
+				pod::Vector3f pointf = transform.position / size;
+				pod::Vector3i point = {
+					(int) (pointf.x + (pointf.x > 0 ? 0.5 : -0.5)),
+					(int) (pointf.y + (pointf.y > 0 ? 0.5 : -0.5)),
+					(int) (pointf.z + (pointf.z > 0 ? 0.5 : -0.5)),
+				};
+			//	std::cout << entity.getName() << ": " << entity.getUid() << ": " << point.x << ", " << point.y << ", " << point.z << std::endl;
+				if ( !this->exists(point) ) continue;
+				ext::Region* regionPointer = this->at(point);
+				if ( !regionPointer ) continue;
+				ext::Region& region = *regionPointer;
+			*/
+			
+				auto& generator = region.getComponent<ext::TerrainGenerator>();
+			
+				auto& regionPosition = region.getComponent<pod::Transform<>>().position;
+				pod::Vector3f voxelPosition = transform.position - regionPosition;
+				voxelPosition.x += size.x / 2.0f;
+				voxelPosition.y += size.y / 2.0f + 1;
+				voxelPosition.z += size.z / 2.0f;
+
+				uf::Collider collider;
+				std::vector<pod::Vector3ui> positions = {
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x - 1, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x + 1, voxelPosition.y, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y - 1, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y + 1, voxelPosition.z },
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z - 1 },
+					{ voxelPosition.x, voxelPosition.y, voxelPosition.z + 1},
+				};
+				for ( auto& position : positions ) {
+					ext::TerrainVoxel voxel = ext::TerrainVoxel::atlas( generator.getVoxel( position.x, position.y, position.z ) );
+					pod::Vector3 offset = regionPosition;
+					offset.x += position.x - (size.x / 2.0f);
+					offset.y += position.y - (size.y / 2.0f);
+					offset.z += position.z - (size.z / 2.0f);
+
+					if ( !voxel.solid() ) continue;
+
+					collider.add( new uf::BoundingBox( offset, {0.5, 0.5, 0.5} ) );
+				/*
+					uf::BaseMesh<pod::Vertex_3F> mesh;
+					const ext::TerrainVoxel::Model& model = voxel.model();
+					#define TERRAIN_SHOULD_RENDER_FACE(SIDE)\
+						for ( uint i = 0; i < model.position.SIDE.size() / 3; ++i ) {\
+							auto& vertex = mesh.vertices.emplace_back();\
+							{\
+								pod::Vector3f& p = vertex.position;\
+								p.x = model.position.SIDE[i*3+0]; p.y = model.position.SIDE[i*3+1]; p.z = model.position.SIDE[i*3+2];\
+								p.x += offset.x; p.y += offset.y; p.z += offset.z;\
+							}\
+						}
+					TERRAIN_SHOULD_RENDER_FACE(left)
+					TERRAIN_SHOULD_RENDER_FACE(right)
+					TERRAIN_SHOULD_RENDER_FACE(top)
+					TERRAIN_SHOULD_RENDER_FACE(bottom)
+					TERRAIN_SHOULD_RENDER_FACE(back)
+					TERRAIN_SHOULD_RENDER_FACE(front)
+					uf::MeshCollider* mCollider = new uf::MeshCollider();
+					mCollider->setPositions( mesh );
+					pCollider.add(mCollider);
+				*/
+				}
+				testColliders( collider, entity.getComponent<uf::Collider>(), &region, &entity, useStrongest );
+			}
+		
+			// collide with others
+			for ( auto* _a : entities ) {
+				uf::Object& entityA = *_a;
+				for ( auto* _b : entities ) { if ( _a == _b ) continue;
+					uf::Object& entityB = *_b;
+					testColliders( entityA.getComponent<uf::Collider>(), entityB.getComponent<uf::Collider>(), &entityA, &entityB, useStrongest );
+				}
+			}
+		
+			return 0;
+		};
+		if ( local ) function(); else uf::thread::add( thread, function, true );
+	}
+#endif
 	// open gamestate, look for work
 	if ( metadata["system"]["state"] == "open" ) { transitionResolvingState(*this);
 		// cleanup orphans
diff --git a/ext/scenes/world/world.cpp b/ext/scenes/world/world.cpp
index 4bfbf6df..9c1bb015 100644
--- a/ext/scenes/world/world.cpp
+++ b/ext/scenes/world/world.cpp
@@ -293,12 +293,8 @@ void ext::World::tick() {
 		ext::oal.listener( "VELOCITY", { 0, 0, 0 } );
 		ext::oal.listener( "ORIENTATION", { 0, 0, 1, 1, 0, 0 } );
 	}
-}
 
-void ext::World::render() {
-	uf::Scene::render();
-
-	/* Update lights */ {
+	/**/ if ( false ) {
 		uf::Serializer& metadata = this->getComponent<uf::Serializer>();
 		auto& scene = *this;
 		std::vector<ext::vulkan::Graphic*> blitters;
@@ -311,128 +307,14 @@ void ext::World::render() {
 			auto* renderModePointer = (ext::vulkan::DeferredRenderMode*) &renderMode;
 			blitters.push_back(&renderModePointer->blitter);
 		}
-		auto& controller = *scene.getController();
-		auto& camera = controller.getComponent<uf::Camera>();
-	//	auto& uniforms = blitter.uniforms;
-		struct UniformDescriptor {
-			struct Matrices {
-				alignas(16) pod::Matrix4f view[2];
-				alignas(16) pod::Matrix4f projection[2];
-			} matrices;
-			alignas(16) pod::Vector4f ambient;
-			struct Light {
-				alignas(16) pod::Vector4f position;
-				alignas(16) pod::Vector4f color;
-			} lights;
-		};
-		
-		struct SpecializationConstant {
-			int32_t maxLights = 32;
-		} specializationConstants;
-
 		for ( size_t _ = 0; _ < blitters.size(); ++_ ) {
 			auto& blitter = *blitters[_];
-			
-			uint8_t* buffer;
-			size_t len;
-			auto* shader = &blitter.material.shaders.front();
-			
-			for ( auto& _ : blitter.material.shaders ) {
-				if ( _.uniforms.empty() ) continue;
-				auto& userdata = _.uniforms.front();
-				buffer = (uint8_t*) (void*) userdata;
-				len = userdata.data().len;
-				shader = &_;
-				specializationConstants = _.specializationConstants.get<SpecializationConstant>();
-			}
-
-			if ( !buffer ) continue;
-
-			UniformDescriptor* uniforms = (UniformDescriptor*) buffer;
-			for ( std::size_t i = 0; i < 2; ++i ) {
-				uniforms->matrices.view[i] = camera.getView( i );
-				uniforms->matrices.projection[i] = camera.getProjection( i );
-			}
-			{
-				uniforms->ambient.x = metadata["light"]["ambient"][0].asFloat();
-				uniforms->ambient.y = metadata["light"]["ambient"][1].asFloat();
-				uniforms->ambient.z = metadata["light"]["ambient"][2].asFloat();
-				uniforms->ambient.w = metadata["light"]["kexp"].asFloat();
-			}
-			{
-				std::vector<uf::Entity*> entities;
-				std::function<void(uf::Entity*)> filter = [&]( uf::Entity* entity ) {
-					if ( !entity || entity->getName() != "Light" ) return;
-					entities.push_back(entity);
-				};
-				for ( uf::Scene* scene : ext::vulkan::scenes ) { if ( !scene ) continue;
-					scene->process(filter);
-				}
-				{
-					const pod::Vector3& position = controller.getComponent<pod::Transform<>>().position;
-					std::sort( entities.begin(), entities.end(), [&]( const uf::Entity* l, const uf::Entity* r ){
-						if ( !l ) return false; if ( !r ) return true;
-						if ( !l->hasComponent<pod::Transform<>>() ) return false; if ( !r->hasComponent<pod::Transform<>>() ) return true;
-						return uf::vector::magnitude( uf::vector::subtract( l->getComponent<pod::Transform<>>().position, position ) ) < uf::vector::magnitude( uf::vector::subtract( r->getComponent<pod::Transform<>>().position, position ) );
-					} );
-				}
-
-				{
-					uf::Serializer& metadata = controller.getComponent<uf::Serializer>();
-					if ( metadata["light"]["should"].asBool() ) {
-						entities.push_back(&controller);
-					}
-				}
-				UniformDescriptor::Light* lights = (UniformDescriptor::Light*) &buffer[sizeof(UniformDescriptor) - sizeof(UniformDescriptor::Light)];
-				for ( size_t i = 0; i < specializationConstants.maxLights; ++i ) {
-					UniformDescriptor::Light& light = lights[i];
-					light.position = { 0, 0, 0, 0 };
-					light.color = { 0, 0, 0, 0 };
-				}
-				for ( size_t i = 0; i < specializationConstants.maxLights && i < entities.size(); ++i ) {
-					UniformDescriptor::Light& light = lights[i];
-					uf::Entity* entity = entities[i];
-
-					pod::Transform<>& transform = entity->getComponent<pod::Transform<>>();
-					uf::Serializer& metadata = entity->getComponent<uf::Serializer>();
-					
-					light.position.x = transform.position.x;
-					light.position.y = transform.position.y;
-					light.position.z = transform.position.z;
-
-					if ( entity == &controller ) {
-						light.position.y += 2;
-					}
-
-					light.position.w = metadata["light"]["power"].asFloat();
-
-					light.color.x = metadata["light"]["color"][0].asFloat();
-					light.color.y = metadata["light"]["color"][1].asFloat();
-					light.color.z = metadata["light"]["color"][2].asFloat();
-					
-					light.color.w = metadata["light"]["radius"].asFloat();
-				}
-			}
-			// blitter.updateBuffer( (void*) buffer, blitter.uniforms.data().len, 0, false );
-			shader->updateBuffer( (void*) buffer, len, 0, false );
+			blitter.getPipeline().update( blitter );
 		}
 	}
+
 }
 
-uf::Entity* ext::World::getController() {
-	if ( ext::vulkan::currentRenderMode ) {
-		auto& renderMode = *ext::vulkan::currentRenderMode;
-		std::string name = renderMode.name;
-		auto split = uf::string::split( name, ": " );
-		if ( split.front() == "Render Target" ) {
-			uint64_t uid = std::stoi( split.back() );
-			uf::Entity* ent = this->findByUid( uid );
-			if ( ent ) return ent;
-		}
-	}
-	return uf::Scene::getController();
-}
-
-const uf::Entity* ext::World::getController() const {
-	return uf::Scene::getController();
+void ext::World::render() {
+	uf::Scene::render();
 }
\ No newline at end of file
diff --git a/ext/scenes/world/world.h b/ext/scenes/world/world.h
index a31008f0..3daed9a0 100644
--- a/ext/scenes/world/world.h
+++ b/ext/scenes/world/world.h
@@ -12,8 +12,5 @@ namespace ext {
 		virtual void initialize();
 		virtual void tick();
 		virtual void render();
-
-		virtual uf::Entity* getController();
-		virtual const uf::Entity* getController() const;
 	};
 }
\ No newline at end of file