reactphysics3d/testbed/imgui/imguiRenderGL3.cpp

696 lines
24 KiB
C++

//
// Copyright (c) 2009-2010 Mikko Mononen memon@inside.org
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors 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 software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// 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 software.
// 3. This notice may not be removed or altered from any source distribution.
//
// Source altered and distributed from https://github.com/AdrienHerubel/imgui
#define _USE_MATH_DEFINES
#include <math.h>
#include <stdio.h>
#include <GL/glew.h>
/*#ifdef __APPLE__
#include <OpenGL/gl3.h>
#else
#include <GL/gl.h>
#endif
*/
#include "imgui.h"
// Some math headers don't have PI defined.
static const float PI = 3.14159265f;
void imguifree(void* ptr, void* userptr);
void* imguimalloc(size_t size, void* userptr);
#define STBTT_malloc(x,y) imguimalloc(x,y)
#define STBTT_free(x,y) imguifree(x,y)
#define STB_TRUETYPE_IMPLEMENTATION
#include "stb_truetype.h"
void imguifree(void* ptr, void* /*userptr*/)
{
free(ptr);
}
void* imguimalloc(size_t size, void* /*userptr*/)
{
return malloc(size);
}
static const unsigned TEMP_COORD_COUNT = 100;
static float g_tempCoords[TEMP_COORD_COUNT*2];
static float g_tempNormals[TEMP_COORD_COUNT*2];
static float g_tempVertices[TEMP_COORD_COUNT * 12 + (TEMP_COORD_COUNT - 2) * 6];
static float g_tempTextureCoords[TEMP_COORD_COUNT * 12 + (TEMP_COORD_COUNT - 2) * 6];
static float g_tempColors[TEMP_COORD_COUNT * 24 + (TEMP_COORD_COUNT - 2) * 12];
static const int CIRCLE_VERTS = 8*4;
static float g_circleVerts[CIRCLE_VERTS*2];
static stbtt_bakedchar g_cdata[96]; // ASCII 32..126 is 95 glyphs
static GLuint g_ftex = 0;
static GLuint g_whitetex = 0;
static GLuint g_vao = 0;
static GLuint g_vbos[3] = {0, 0, 0};
static GLuint g_program = 0;
static GLuint g_programViewportLocation = 0;
static GLuint g_programTextureLocation = 0;
inline unsigned int RGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
{
return (r) | (g << 8) | (b << 16) | (a << 24);
}
static void drawPolygon(const float* coords, unsigned numCoords, float r, unsigned int col)
{
if (numCoords > TEMP_COORD_COUNT) numCoords = TEMP_COORD_COUNT;
for (unsigned i = 0, j = numCoords-1; i < numCoords; j=i++)
{
const float* v0 = &coords[j*2];
const float* v1 = &coords[i*2];
float dx = v1[0] - v0[0];
float dy = v1[1] - v0[1];
float d = sqrtf(dx*dx+dy*dy);
if (d > 0)
{
d = 1.0f/d;
dx *= d;
dy *= d;
}
g_tempNormals[j*2+0] = dy;
g_tempNormals[j*2+1] = -dx;
}
float colf[4] = { (float) (col&0xff) / 255.f, (float) ((col>>8)&0xff) / 255.f, (float) ((col>>16)&0xff) / 255.f, (float) ((col>>24)&0xff) / 255.f};
float colTransf[4] = { (float) (col&0xff) / 255.f, (float) ((col>>8)&0xff) / 255.f, (float) ((col>>16)&0xff) / 255.f, 0};
for (unsigned i = 0, j = numCoords-1; i < numCoords; j=i++)
{
float dlx0 = g_tempNormals[j*2+0];
float dly0 = g_tempNormals[j*2+1];
float dlx1 = g_tempNormals[i*2+0];
float dly1 = g_tempNormals[i*2+1];
float dmx = (dlx0 + dlx1) * 0.5f;
float dmy = (dly0 + dly1) * 0.5f;
float dmr2 = dmx*dmx + dmy*dmy;
if (dmr2 > 0.000001f)
{
float scale = 1.0f / dmr2;
if (scale > 10.0f) scale = 10.0f;
dmx *= scale;
dmy *= scale;
}
g_tempCoords[i*2+0] = coords[i*2+0]+dmx*r;
g_tempCoords[i*2+1] = coords[i*2+1]+dmy*r;
}
int vSize = numCoords * 12 + (numCoords - 2) * 6;
int uvSize = numCoords * 2 * 6 + (numCoords - 2) * 2 * 3;
int cSize = numCoords * 4 * 6 + (numCoords - 2) * 4 * 3;
float * v = g_tempVertices;
float * uv = g_tempTextureCoords;
memset(uv, 0, uvSize * sizeof(float));
float * c = g_tempColors;
memset(c, 1, cSize * sizeof(float));
float * ptrV = v;
float * ptrC = c;
for (unsigned i = 0, j = numCoords-1; i < numCoords; j=i++)
{
*ptrV = coords[i*2];
*(ptrV+1) = coords[i*2 + 1];
ptrV += 2;
*ptrV = coords[j*2];
*(ptrV+1) = coords[j*2 + 1];
ptrV += 2;
*ptrV = g_tempCoords[j*2];
*(ptrV+1) = g_tempCoords[j*2 + 1];
ptrV += 2;
*ptrV = g_tempCoords[j*2];
*(ptrV+1) = g_tempCoords[j*2 + 1];
ptrV += 2;
*ptrV = g_tempCoords[i*2];
*(ptrV+1) = g_tempCoords[i*2 + 1];
ptrV += 2;
*ptrV = coords[i*2];
*(ptrV+1) = coords[i*2 + 1];
ptrV += 2;
*ptrC = colf[0];
*(ptrC+1) = colf[1];
*(ptrC+2) = colf[2];
*(ptrC+3) = colf[3];
ptrC += 4;
*ptrC = colf[0];
*(ptrC+1) = colf[1];
*(ptrC+2) = colf[2];
*(ptrC+3) = colf[3];
ptrC += 4;
*ptrC = colTransf[0];
*(ptrC+1) = colTransf[1];
*(ptrC+2) = colTransf[2];
*(ptrC+3) = colTransf[3];
ptrC += 4;
*ptrC = colTransf[0];
*(ptrC+1) = colTransf[1];
*(ptrC+2) = colTransf[2];
*(ptrC+3) = colTransf[3];
ptrC += 4;
*ptrC = colTransf[0];
*(ptrC+1) = colTransf[1];
*(ptrC+2) = colTransf[2];
*(ptrC+3) = colTransf[3];
ptrC += 4;
*ptrC = colf[0];
*(ptrC+1) = colf[1];
*(ptrC+2) = colf[2];
*(ptrC+3) = colf[3];
ptrC += 4;
}
for (unsigned i = 2; i < numCoords; ++i)
{
*ptrV = coords[0];
*(ptrV+1) = coords[1];
ptrV += 2;
*ptrV = coords[(i-1)*2];
*(ptrV+1) = coords[(i-1)*2+1];
ptrV += 2;
*ptrV = coords[i*2];
*(ptrV+1) = coords[i*2 + 1];
ptrV += 2;
*ptrC = colf[0];
*(ptrC+1) = colf[1];
*(ptrC+2) = colf[2];
*(ptrC+3) = colf[3];
ptrC += 4;
*ptrC = colf[0];
*(ptrC+1) = colf[1];
*(ptrC+2) = colf[2];
*(ptrC+3) = colf[3];
ptrC += 4;
*ptrC = colf[0];
*(ptrC+1) = colf[1];
*(ptrC+2) = colf[2];
*(ptrC+3) = colf[3];
ptrC += 4;
}
glBindTexture(GL_TEXTURE_2D, g_whitetex);
glBindVertexArray(g_vao);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[0]);
glBufferData(GL_ARRAY_BUFFER, vSize*sizeof(float), v, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[1]);
glBufferData(GL_ARRAY_BUFFER, uvSize*sizeof(float), uv, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[2]);
glBufferData(GL_ARRAY_BUFFER, cSize*sizeof(float), c, GL_STATIC_DRAW);
glDrawArrays(GL_TRIANGLES, 0, (numCoords * 2 + numCoords - 2)*3);
}
static void drawRect(float x, float y, float w, float h, float fth, unsigned int col)
{
float verts[4*2] =
{
x+0.5f, y+0.5f,
x+w-0.5f, y+0.5f,
x+w-0.5f, y+h-0.5f,
x+0.5f, y+h-0.5f,
};
drawPolygon(verts, 4, fth, col);
}
/*
static void drawEllipse(float x, float y, float w, float h, float fth, unsigned int col)
{
float verts[CIRCLE_VERTS*2];
const float* cverts = g_circleVerts;
float* v = verts;
for (int i = 0; i < CIRCLE_VERTS; ++i)
{
*v++ = x + cverts[i*2]*w;
*v++ = y + cverts[i*2+1]*h;
}
drawPolygon(verts, CIRCLE_VERTS, fth, col);
}
*/
static void drawRoundedRect(float x, float y, float w, float h, float r, float fth, unsigned int col)
{
const unsigned n = CIRCLE_VERTS/4;
float verts[(n+1)*4*2];
const float* cverts = g_circleVerts;
float* v = verts;
for (unsigned i = 0; i <= n; ++i)
{
*v++ = x+w-r + cverts[i*2]*r;
*v++ = y+h-r + cverts[i*2+1]*r;
}
for (unsigned i = n; i <= n*2; ++i)
{
*v++ = x+r + cverts[i*2]*r;
*v++ = y+h-r + cverts[i*2+1]*r;
}
for (unsigned i = n*2; i <= n*3; ++i)
{
*v++ = x+r + cverts[i*2]*r;
*v++ = y+r + cverts[i*2+1]*r;
}
for (unsigned i = n*3; i < n*4; ++i)
{
*v++ = x+w-r + cverts[i*2]*r;
*v++ = y+r + cverts[i*2+1]*r;
}
*v++ = x+w-r + cverts[0]*r;
*v++ = y+r + cverts[1]*r;
drawPolygon(verts, (n+1)*4, fth, col);
}
static void drawLine(float x0, float y0, float x1, float y1, float r, float fth, unsigned int col)
{
float dx = x1-x0;
float dy = y1-y0;
float d = sqrtf(dx*dx+dy*dy);
if (d > 0.0001f)
{
d = 1.0f/d;
dx *= d;
dy *= d;
}
float nx = dy;
float ny = -dx;
float verts[4*2];
r -= fth;
r *= 0.5f;
if (r < 0.01f) r = 0.01f;
dx *= r;
dy *= r;
nx *= r;
ny *= r;
verts[0] = x0-dx-nx;
verts[1] = y0-dy-ny;
verts[2] = x0-dx+nx;
verts[3] = y0-dy+ny;
verts[4] = x1+dx+nx;
verts[5] = y1+dy+ny;
verts[6] = x1+dx-nx;
verts[7] = y1+dy-ny;
drawPolygon(verts, 4, fth, col);
}
bool imguiRenderGLInit(const char* fontpath)
{
for (int i = 0; i < CIRCLE_VERTS; ++i)
{
float a = (float)i/(float)CIRCLE_VERTS * PI*2;
g_circleVerts[i*2+0] = cosf(a);
g_circleVerts[i*2+1] = sinf(a);
}
// Load font.
FILE* fp = fopen(fontpath, "rb");
if (!fp) return false;
fseek(fp, 0, SEEK_END);
int size = ftell(fp);
fseek(fp, 0, SEEK_SET);
unsigned char* ttfBuffer = (unsigned char*)malloc(size);
if (!ttfBuffer)
{
fclose(fp);
return false;
}
fread(ttfBuffer, 1, size, fp);
fclose(fp);
fp = 0;
unsigned char* bmap = (unsigned char*)malloc(512*512);
if (!bmap)
{
free(ttfBuffer);
return false;
}
stbtt_BakeFontBitmap(ttfBuffer,0, FONT_HEIGHT, bmap,512,512, 32,96, g_cdata);
// can free ttf_buffer at this point
glGenTextures(1, &g_ftex);
glBindTexture(GL_TEXTURE_2D, g_ftex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 512,512, 0, GL_RED, GL_UNSIGNED_BYTE, bmap);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// can free ttf_buffer at this point
unsigned char white_alpha = 255;
glGenTextures(1, &g_whitetex);
glBindTexture(GL_TEXTURE_2D, g_whitetex);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 1, 1, 0, GL_RED, GL_UNSIGNED_BYTE, &white_alpha);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glGenVertexArrays(1, &g_vao);
glGenBuffers(3, g_vbos);
glBindVertexArray(g_vao);
glEnableVertexAttribArray(0);
glEnableVertexAttribArray(1);
glEnableVertexAttribArray(2);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[0]);
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(GL_FLOAT)*2, (void*)0);
glBufferData(GL_ARRAY_BUFFER, 0, 0, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[1]);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(GL_FLOAT)*2, (void*)0);
glBufferData(GL_ARRAY_BUFFER, 0, 0, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[2]);
glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, sizeof(GL_FLOAT)*4, (void*)0);
glBufferData(GL_ARRAY_BUFFER, 0, 0, GL_STATIC_DRAW);
g_program = glCreateProgram();
const char * vs =
"#version 150\n"
"uniform vec2 Viewport;\n"
"in vec2 VertexPosition;\n"
"in vec2 VertexTexCoord;\n"
"in vec4 VertexColor;\n"
"out vec2 texCoord;\n"
"out vec4 vertexColor;\n"
"void main(void)\n"
"{\n"
" vertexColor = VertexColor;\n"
" texCoord = VertexTexCoord;\n"
" gl_Position = vec4(VertexPosition * 2.0 / Viewport - 1.0, 0.f, 1.0);\n"
"}\n";
GLuint vso = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vso, 1, (const char **) &vs, NULL);
glCompileShader(vso);
glAttachShader(g_program, vso);
const char * fs =
"#version 150\n"
"in vec2 texCoord;\n"
"in vec4 vertexColor;\n"
"uniform sampler2D Texture;\n"
"out vec4 Color;\n"
"void main(void)\n"
"{\n"
" float alpha = texture(Texture, texCoord).r;\n"
" Color = vec4(vertexColor.rgb, vertexColor.a * alpha);\n"
"}\n";
GLuint fso = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fso, 1, (const char **) &fs, NULL);
glCompileShader(fso);
glAttachShader(g_program, fso);
glBindAttribLocation(g_program, 0, "VertexPosition");
glBindAttribLocation(g_program, 1, "VertexTexCoord");
glBindAttribLocation(g_program, 2, "VertexColor");
glBindFragDataLocation(g_program, 0, "Color");
glLinkProgram(g_program);
glDeleteShader(vso);
glDeleteShader(fso);
glUseProgram(g_program);
g_programViewportLocation = glGetUniformLocation(g_program, "Viewport");
g_programTextureLocation = glGetUniformLocation(g_program, "Texture");
glUseProgram(0);
free(ttfBuffer);
free(bmap);
return true;
}
void imguiRenderGLDestroy()
{
if (g_ftex)
{
glDeleteTextures(1, &g_ftex);
g_ftex = 0;
}
if (g_vao)
{
glDeleteVertexArrays(1, &g_vao);
glDeleteBuffers(3, g_vbos);
g_vao = 0;
}
if (g_program)
{
glDeleteProgram(g_program);
g_program = 0;
}
}
static void getBakedQuad(stbtt_bakedchar *chardata, int pw, int ph, int char_index,
float *xpos, float *ypos, stbtt_aligned_quad *q)
{
stbtt_bakedchar *b = chardata + char_index;
int round_x = STBTT_ifloor(*xpos + b->xoff);
int round_y = STBTT_ifloor(*ypos - b->yoff);
q->x0 = (float)round_x;
q->y0 = (float)round_y;
q->x1 = (float)round_x + b->x1 - b->x0;
q->y1 = (float)round_y - b->y1 + b->y0;
q->s0 = b->x0 / (float)pw;
q->t0 = b->y0 / (float)pw;
q->s1 = b->x1 / (float)ph;
q->t1 = b->y1 / (float)ph;
*xpos += b->xadvance;
}
static const float g_tabStops[4] = {150, 210, 270, 330};
static float getTextLength(stbtt_bakedchar *chardata, const char* text)
{
float xpos = 0;
float len = 0;
while (*text)
{
int c = (unsigned char)*text;
if (c == '\t')
{
for (int i = 0; i < 4; ++i)
{
if (xpos < g_tabStops[i])
{
xpos = g_tabStops[i];
break;
}
}
}
else if (c >= 32 && c < 128)
{
stbtt_bakedchar *b = chardata + c-32;
int round_x = STBTT_ifloor((xpos + b->xoff) + 0.5);
len = round_x + b->x1 - b->x0 + 0.5f;
xpos += b->xadvance;
}
++text;
}
return len;
}
static void drawText(float x, float y, const char *text, int align, unsigned int col)
{
if (!g_ftex) return;
if (!text) return;
if (align == IMGUI_ALIGN_CENTER)
x -= getTextLength(g_cdata, text)/2;
else if (align == IMGUI_ALIGN_RIGHT)
x -= getTextLength(g_cdata, text);
float r = (float) (col&0xff) / 255.f;
float g = (float) ((col>>8)&0xff) / 255.f;
float b = (float) ((col>>16)&0xff) / 255.f;
float a = (float) ((col>>24)&0xff) / 255.f;
// assume orthographic projection with units = screen pixels, origin at top left
glBindTexture(GL_TEXTURE_2D, g_ftex);
const float ox = x;
while (*text)
{
int c = (unsigned char)*text;
if (c == '\t')
{
for (int i = 0; i < 4; ++i)
{
if (x < g_tabStops[i]+ox)
{
x = g_tabStops[i]+ox;
break;
}
}
}
else if (c >= 32 && c < 128)
{
stbtt_aligned_quad q;
getBakedQuad(g_cdata, 512,512, c-32, &x,&y,&q);
float v[12] = {
q.x0, q.y0,
q.x1, q.y1,
q.x1, q.y0,
q.x0, q.y0,
q.x0, q.y1,
q.x1, q.y1,
};
float uv[12] = {
q.s0, q.t0,
q.s1, q.t1,
q.s1, q.t0,
q.s0, q.t0,
q.s0, q.t1,
q.s1, q.t1,
};
float c[24] = {
r, g, b, a,
r, g, b, a,
r, g, b, a,
r, g, b, a,
r, g, b, a,
r, g, b, a,
};
glBindVertexArray(g_vao);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[0]);
glBufferData(GL_ARRAY_BUFFER, 12*sizeof(float), v, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[1]);
glBufferData(GL_ARRAY_BUFFER, 12*sizeof(float), uv, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, g_vbos[2]);
glBufferData(GL_ARRAY_BUFFER, 24*sizeof(float), c, GL_STATIC_DRAW);
glDrawArrays(GL_TRIANGLES, 0, 6);
}
++text;
}
//glEnd();
//glDisable(GL_TEXTURE_2D);
}
void imguiRenderGLDraw(int width, int height)
{
const imguiGfxCmd* q = imguiGetRenderQueue();
int nq = imguiGetRenderQueueSize();
const float s = 1.0f/8.0f;
glViewport(0, 0, width, height);
glUseProgram(g_program);
glActiveTexture(GL_TEXTURE0);
glUniform2f(g_programViewportLocation, (float) width, (float) height);
glUniform1i(g_programTextureLocation, 0);
glDisable(GL_SCISSOR_TEST);
for (int i = 0; i < nq; ++i)
{
const imguiGfxCmd& cmd = q[i];
if (cmd.type == IMGUI_GFXCMD_RECT)
{
if (cmd.rect.r == 0)
{
drawRect((float)cmd.rect.x*s+0.5f, (float)cmd.rect.y*s+0.5f,
(float)cmd.rect.w*s-1, (float)cmd.rect.h*s-1,
1.0f, cmd.col);
}
else
{
drawRoundedRect((float)cmd.rect.x*s+0.5f, (float)cmd.rect.y*s+0.5f,
(float)cmd.rect.w*s-1, (float)cmd.rect.h*s-1,
(float)cmd.rect.r*s, 1.0f, cmd.col);
}
}
else if (cmd.type == IMGUI_GFXCMD_LINE)
{
drawLine(cmd.line.x0*s, cmd.line.y0*s, cmd.line.x1*s, cmd.line.y1*s, cmd.line.r*s, 1.0f, cmd.col);
}
else if (cmd.type == IMGUI_GFXCMD_TRIANGLE)
{
if (cmd.flags == 1)
{
const float verts[3*2] =
{
(float)cmd.rect.x*s+0.5f, (float)cmd.rect.y*s+0.5f,
(float)cmd.rect.x*s+0.5f+(float)cmd.rect.w*s-1, (float)cmd.rect.y*s+0.5f+(float)cmd.rect.h*s/2-0.5f,
(float)cmd.rect.x*s+0.5f, (float)cmd.rect.y*s+0.5f+(float)cmd.rect.h*s-1,
};
drawPolygon(verts, 3, 1.0f, cmd.col);
}
if (cmd.flags == 2)
{
const float verts[3*2] =
{
(float)cmd.rect.x*s+0.5f, (float)cmd.rect.y*s+0.5f+(float)cmd.rect.h*s-1,
(float)cmd.rect.x*s+0.5f+(float)cmd.rect.w*s/2-0.5f, (float)cmd.rect.y*s+0.5f,
(float)cmd.rect.x*s+0.5f+(float)cmd.rect.w*s-1, (float)cmd.rect.y*s+0.5f+(float)cmd.rect.h*s-1,
};
drawPolygon(verts, 3, 1.0f, cmd.col);
}
}
else if (cmd.type == IMGUI_GFXCMD_TEXT)
{
drawText(cmd.text.x, cmd.text.y, cmd.text.text, cmd.text.align, cmd.col);
}
else if (cmd.type == IMGUI_GFXCMD_SCISSOR)
{
if (cmd.flags)
{
glEnable(GL_SCISSOR_TEST);
glScissor(cmd.rect.x, cmd.rect.y, cmd.rect.w, cmd.rect.h);
}
else
{
glDisable(GL_SCISSOR_TEST);
}
}
}
glDisable(GL_SCISSOR_TEST);
}