engine/bin/data/shaders/gltf.frag.glsl
2021-02-12 00:00:00 -06:00

139 lines
3.5 KiB
GLSL

#version 450
#define UF_DEFERRED_SAMPLING 0
#define UF_CAN_DISCARD 1
layout (constant_id = 0) const uint TEXTURES = 1;
layout (binding = 0) uniform sampler2D samplerTextures[TEXTURES];
struct Material {
vec4 colorBase;
vec4 colorEmissive;
float factorMetallic;
float factorRoughness;
float factorOcclusion;
float factorAlphaCutoff;
int indexAlbedo;
int indexNormal;
int indexEmissive;
int indexOcclusion;
int indexMetallicRoughness;
int modeAlpha;
int padding1;
int padding2;
};
struct Texture {
int index;
int samp;
int remap;
float blend;
vec4 lerp;
};
layout (std140, binding = 1) readonly buffer Materials {
Material materials[];
};
layout (std140, binding = 2) readonly buffer Textures {
Texture textures[];
};
layout (location = 0) in vec2 inUv;
layout (location = 1) in vec4 inColor;
layout (location = 2) in vec3 inNormal;
layout (location = 3) in mat3 inTBN;
layout (location = 6) in vec3 inPosition;
layout (location = 7) flat in ivec4 inId;
layout (location = 0) out uvec2 outId;
layout (location = 1) out vec2 outNormals;
#if UF_DEFERRED_SAMPLING
layout (location = 2) out vec2 outUvs;
#else
layout (location = 2) out vec4 outAlbedo;
#endif
vec2 encodeNormals( vec3 n ) {
float p = sqrt(n.z*8+8);
return n.xy/p + 0.5;
}
float wrap( float i ) {
return fract(i);
}
vec2 wrap( vec2 uv ) {
return vec2( wrap( uv.x ), wrap( uv.y ) );
}
float mipLevel( in vec2 uv ) {
vec2 dx_vtc = dFdx(uv);
vec2 dy_vtc = dFdy(uv);
return 0.5 * log2(max(dot(dx_vtc, dx_vtc), dot(dy_vtc, dy_vtc)));
}
bool validTextureIndex( int textureIndex ) {
return 0 <= textureIndex && textureIndex < TEXTURES;
}
void main() {
float mip = mipLevel(inUv.xy);
vec2 uv = wrap(inUv.xy);
vec4 C = vec4(0, 0, 0, 0);
vec3 P = inPosition;
vec3 N = inNormal;
#if UF_DEFERRED_SAMPLING
outUvs = wrap(inUv.xy);
vec4 outAlbedo = vec4(0,0,0,0);
#endif
#if !UF_DEFERRED_SAMPLING || UF_CAN_DISCARD
int materialId = int(inId.y);
Material material = materials[materialId];
float M = material.factorMetallic;
float R = material.factorRoughness;
float AO = material.factorOcclusion;
// sample albedo
if ( !validTextureIndex( material.indexAlbedo ) ) discard; {
Texture t = textures[material.indexAlbedo + 1];
C = textureLod( samplerTextures[0], mix( t.lerp.xy, t.lerp.zw, uv ), mip );
// alpha mode OPAQUE
if ( material.modeAlpha == 0 ) {
C.a = 1;
// alpha mode BLEND
} else if ( material.modeAlpha == 1 ) {
// alpha mode MASK
} else if ( material.modeAlpha == 2 ) {
if ( C.a < abs(material.factorAlphaCutoff) ) discard;
C.a = 1;
}
}
#endif
#if !UF_DEFERRED_SAMPLING
// sample normal
if ( validTextureIndex( material.indexNormal ) ) {
Texture t = textures[material.indexNormal + 1];
N = inTBN * normalize( textureLod( samplerTextures[0], mix( t.lerp.xy, t.lerp.zw, uv ), mip ).xyz * 2.0 - vec3(1.0));
}
#if 0
// sample metallic/roughness
if ( validTextureIndex( material.indexMetallicRoughness ) ) {
Texture t = textures[material.indexMetallicRoughness + 1];
vec4 sampled = texture( samplerTextures[0], mix( t.lerp.xy, t.lerp.zw, uv ), mip );
M = sampled.b;
R = sampled.g;
}
// sample ao
AO = material.factorOcclusion;
if ( validTextureIndex( material.indexOcclusion ) ) {
Texture t = textures[material.indexMetallicRoughness + 1];
AO = texture( samplerTextures[0], mix( t.lerp.xy, t.lerp.zw, uv ) ).r;
}
#endif
outAlbedo = C * inColor;
#endif
outNormals = encodeNormals( N );
outId = ivec2(inId.w+1, inId.y+1);
}