git.cworth.org Git - apitrace/blob - glstate.cpp

   1 /**************************************************************************
   2  *
   3  * Copyright 2011 Jose Fonseca
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  *
  24  **************************************************************************/
  25
  26
  27 #include <string.h>
  28 #include <iostream>
  29 #include <algorithm>
  30
  31 #include "image.hpp"
  32 #include "json.hpp"
  33 #include "glproc.hpp"
  34 #include "glsize.hpp"
  35 #include "glstate.hpp"
  36
  37
  38 #ifdef __APPLE__
  39
  40 #include <Carbon/Carbon.h>
  41
  42 #ifdef __cplusplus
  43 extern "C" {
  44 #endif
  45
  46 typedef int CGSConnectionID;
  47 typedef int CGSWindowID;
  48 typedef int CGSSurfaceID;
  49
  50 CGLError CGLGetSurface(CGLContextObj, CGSConnectionID*, CGSWindowID*, CGSSurfaceID*);
  51 OSStatus CGSGetSurfaceBounds(CGSConnectionID, CGWindowID, CGSSurfaceID, CGRect *);
  52
  53 #ifdef __cplusplus
  54 }
  55 #endif
  56
  57 #endif /* __APPLE__ */
  58
  59
  60 namespace glstate {
  61
  62
  63 static void
  64 dumpShader(JSONWriter &json, GLuint shader)
  65 {
  66     if (!shader) {
  67         return;
  68     }
  69
  70     GLint shader_type = 0;
  71     glGetShaderiv(shader, GL_SHADER_TYPE, &shader_type);
  72     if (!shader_type) {
  73         return;
  74     }
  75
  76     GLint source_length = 0;
  77     glGetShaderiv(shader, GL_SHADER_SOURCE_LENGTH, &source_length);
  78     if (!source_length) {
  79         return;
  80     }
  81
  82     GLchar *source = new GLchar[source_length];
  83     GLsizei length = 0;
  84     source[0] = 0;
  85     glGetShaderSource(shader, source_length, &length, source);
  86
  87     json.beginMember(enumToString(shader_type));
  88     json.writeString(source);
  89     json.endMember();
  90
  91     delete [] source;
  92 }
  93
  94
  95 static void
  96 dumpShaderObj(JSONWriter &json, GLhandleARB shaderObj)
  97 {
  98     if (!shaderObj) {
  99         return;
 100     }
 101
 102     GLint shader_type = 0;
 103     glGetObjectParameterivARB(shaderObj, GL_OBJECT_TYPE_ARB, &shader_type);
 104     if (!shader_type) {
 105         return;
 106     }
 107
 108     GLint source_length = 0;
 109     glGetObjectParameterivARB(shaderObj, GL_OBJECT_SHADER_SOURCE_LENGTH_ARB, &source_length);
 110     if (!source_length) {
 111         return;
 112     }
 113
 114     GLcharARB *source = new GLcharARB[source_length];
 115     GLsizei length = 0;
 116     source[0] = 0;
 117     glGetShaderSource(shaderObj, source_length, &length, source);
 118
 119     json.beginMember(enumToString(shader_type));
 120     json.writeString(source);
 121     json.endMember();
 122
 123     delete [] source;
 124 }
 125
 126
 127 static inline void
 128 dumpCurrentProgram(JSONWriter &json)
 129 {
 130     GLint program = 0;
 131     glGetIntegerv(GL_CURRENT_PROGRAM, &program);
 132     if (!program) {
 133         return;
 134     }
 135
 136     GLint attached_shaders = 0;
 137     glGetProgramiv(program, GL_ATTACHED_SHADERS, &attached_shaders);
 138     if (!attached_shaders) {
 139         return;
 140     }
 141
 142     GLuint *shaders = new GLuint[attached_shaders];
 143     GLsizei count = 0;
 144     glGetAttachedShaders(program, attached_shaders, &count, shaders);
 145     for (GLsizei i = 0; i < count; ++ i) {
 146        dumpShader(json, shaders[i]);
 147     }
 148     delete [] shaders;
 149 }
 150
 151
 152 static inline void
 153 dumpCurrentProgramObj(JSONWriter &json)
 154 {
 155     GLhandleARB programObj = glGetHandleARB(GL_PROGRAM_OBJECT_ARB);
 156     if (!programObj) {
 157         return;
 158     }
 159
 160     GLint attached_shaders = 0;
 161     glGetProgramivARB(programObj, GL_OBJECT_ATTACHED_OBJECTS_ARB, &attached_shaders);
 162     if (!attached_shaders) {
 163         return;
 164     }
 165
 166     GLhandleARB *shaderObjs = new GLhandleARB[attached_shaders];
 167     GLsizei count = 0;
 168     glGetAttachedObjectsARB(programObj, attached_shaders, &count, shaderObjs);
 169     for (GLsizei i = 0; i < count; ++ i) {
 170        dumpShaderObj(json, shaderObjs[i]);
 171     }
 172     delete [] shaderObjs;
 173 }
 174
 175
 176 static inline void
 177 dumpArbProgram(JSONWriter &json, GLenum target)
 178 {
 179     if (!glIsEnabled(target)) {
 180         return;
 181     }
 182
 183     GLint program_length = 0;
 184     glGetProgramivARB(target, GL_PROGRAM_LENGTH_ARB, &program_length);
 185     if (!program_length) {
 186         return;
 187     }
 188
 189     GLchar *source = new GLchar[program_length + 1];
 190     source[0] = 0;
 191     glGetProgramStringARB(target, GL_PROGRAM_STRING_ARB, source);
 192     source[program_length] = 0;
 193
 194     json.beginMember(enumToString(target));
 195     json.writeString(source);
 196     json.endMember();
 197
 198     delete [] source;
 199 }
 200
 201
 202 static inline void
 203 dumpShaders(JSONWriter &json)
 204 {
 205     json.beginMember("shaders");
 206     json.beginObject();
 207     dumpCurrentProgram(json);
 208     dumpArbProgram(json, GL_FRAGMENT_PROGRAM_ARB);
 209     dumpArbProgram(json, GL_VERTEX_PROGRAM_ARB);
 210     json.endObject();
 211     json.endMember(); //shaders
 212 }
 213
 214
 215 static inline void
 216 dumpTextureImage(JSONWriter &json, GLenum target, GLint level)
 217 {
 218     GLint width, height = 1, depth = 1;
 219
 220     width = 0;
 221     glGetTexLevelParameteriv(target, level, GL_TEXTURE_WIDTH, &width);
 222
 223     if (target != GL_TEXTURE_1D) {
 224         height = 0;
 225         glGetTexLevelParameteriv(target, level, GL_TEXTURE_HEIGHT, &height);
 226         if (target == GL_TEXTURE_3D) {
 227             depth = 0;
 228             glGetTexLevelParameteriv(target, level, GL_TEXTURE_DEPTH, &depth);
 229         }
 230     }
 231
 232     if (width <= 0 || height <= 0 || depth <= 0) {
 233         return;
 234     } else {
 235         char label[512];
 236
 237         GLint active_texture = GL_TEXTURE0;
 238         glGetIntegerv(GL_ACTIVE_TEXTURE, &active_texture);
 239         snprintf(label, sizeof label, "%s, %s, level = %i", enumToString(active_texture), enumToString(target), level);
 240
 241         json.beginMember(label);
 242
 243         json.beginObject();
 244
 245         // Tell the GUI this is no ordinary object, but an image
 246         json.writeStringMember("__class__", "image");
 247
 248         json.writeNumberMember("__width__", width);
 249         json.writeNumberMember("__height__", height);
 250         json.writeNumberMember("__depth__", depth);
 251
 252         // Hardcoded for now, but we could chose types more adequate to the
 253         // texture internal format
 254         json.writeStringMember("__type__", "uint8");
 255         json.writeBoolMember("__normalized__", true);
 256         json.writeNumberMember("__channels__", 4);
 257
 258         GLubyte *pixels = new GLubyte[depth*width*height*4];
 259
 260         glGetTexImage(target, level, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
 261
 262         json.beginMember("__data__");
 263         char *pngBuffer;
 264         int pngBufferSize;
 265         Image::writePixelsToBuffer(pixels, width, height, 4, false, &pngBuffer, &pngBufferSize);
 266         json.writeBase64(pngBuffer, pngBufferSize);
 267         free(pngBuffer);
 268         json.endMember(); // __data__
 269
 270         delete [] pixels;
 271         json.endObject();
 272     }
 273 }
 274
 275
 276 static inline void
 277 dumpTexture(JSONWriter &json, GLenum target, GLenum binding)
 278 {
 279     GLint texture_binding = 0;
 280     glGetIntegerv(binding, &texture_binding);
 281     if (!glIsEnabled(target) && !texture_binding) {
 282         return;
 283     }
 284
 285     GLint level = 0;
 286     do {
 287         GLint width = 0, height = 0;
 288         glGetTexLevelParameteriv(target, level, GL_TEXTURE_WIDTH, &width);
 289         glGetTexLevelParameteriv(target, level, GL_TEXTURE_HEIGHT, &height);
 290         if (!width || !height) {
 291             break;
 292         }
 293
 294         if (target == GL_TEXTURE_CUBE_MAP) {
 295             for (int face = 0; face < 6; ++face) {
 296                 dumpTextureImage(json, GL_TEXTURE_CUBE_MAP_POSITIVE_X + face, level);
 297             }
 298         } else {
 299             dumpTextureImage(json, target, level);
 300         }
 301
 302         ++level;
 303     } while(true);
 304 }
 305
 306
 307 static inline void
 308 dumpTextures(JSONWriter &json)
 309 {
 310     json.beginMember("textures");
 311     json.beginObject();
 312     GLint active_texture = GL_TEXTURE0;
 313     glGetIntegerv(GL_ACTIVE_TEXTURE, &active_texture);
 314     GLint max_texture_coords = 0;
 315     glGetIntegerv(GL_MAX_TEXTURE_COORDS, &max_texture_coords);
 316     GLint max_combined_texture_image_units = 0;
 317     glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &max_combined_texture_image_units);
 318     GLint max_units = std::max(max_combined_texture_image_units, max_texture_coords);
 319     for (GLint unit = 0; unit < max_units; ++unit) {
 320         GLenum texture = GL_TEXTURE0 + unit;
 321         glActiveTexture(texture);
 322         dumpTexture(json, GL_TEXTURE_1D, GL_TEXTURE_BINDING_1D);
 323         dumpTexture(json, GL_TEXTURE_2D, GL_TEXTURE_BINDING_2D);
 324         dumpTexture(json, GL_TEXTURE_3D, GL_TEXTURE_BINDING_3D);
 325         dumpTexture(json, GL_TEXTURE_RECTANGLE, GL_TEXTURE_BINDING_RECTANGLE);
 326         dumpTexture(json, GL_TEXTURE_CUBE_MAP, GL_TEXTURE_BINDING_CUBE_MAP);
 327     }
 328     glActiveTexture(active_texture);
 329     json.endObject();
 330     json.endMember(); // textures
 331 }
 332
 333
 334 static bool
 335 getDrawableBounds(GLint *width, GLint *height) {
 336 #if defined(_WIN32)
 337
 338     HDC hDC = wglGetCurrentDC();
 339     if (!hDC) {
 340         return false;
 341     }
 342
 343     HWND hWnd = WindowFromDC(hDC);
 344     RECT rect;
 345
 346     if (!GetClientRect(hWnd, &rect)) {
 347        return false;
 348     }
 349
 350     *width  = rect.right  - rect.left;
 351     *height = rect.bottom - rect.top;
 352
 353 #elif defined(__APPLE__)
 354
 355     CGLContextObj ctx = CGLGetCurrentContext();
 356     if (ctx == NULL) {
 357         return false;
 358     }
 359
 360     CGSConnectionID cid;
 361     CGSWindowID wid;
 362     CGSSurfaceID sid;
 363
 364     if (CGLGetSurface(ctx, &cid, &wid, &sid) != kCGLNoError) {
 365         return false;
 366     }
 367
 368     CGRect rect;
 369
 370     if (CGSGetSurfaceBounds(cid, wid, sid, &rect) != 0) {
 371         return false;
 372     }
 373
 374     *width = rect.size.width;
 375     *height = rect.size.height;
 376
 377 #else
 378
 379     Display *display;
 380     Drawable drawable;
 381     Window root;
 382     int x, y;
 383     unsigned int w, h, bw, depth;
 384
 385     display = glXGetCurrentDisplay();
 386     if (!display) {
 387         return false;
 388     }
 389
 390     drawable = glXGetCurrentDrawable();
 391     if (drawable == None) {
 392         return false;
 393     }
 394
 395     if (!XGetGeometry(display, drawable, &root, &x, &y, &w, &h, &bw, &depth)) {
 396         return false;
 397     }
 398
 399     *width = w;
 400     *height = h;
 401
 402 #endif
 403
 404     return true;
 405 }
 406
 407
 408 static inline void
 409 dumpDrawBufferImage(JSONWriter &json, GLenum format)
 410 {
 411     GLint channels = __gl_format_channels(format);
 412
 413     GLint width, height;
 414
 415     if (!getDrawableBounds(&width, &height)) {
 416         json.writeNull();
 417     } else {
 418         json.beginObject();
 419
 420         // Tell the GUI this is no ordinary object, but an image
 421         json.writeStringMember("__class__", "image");
 422
 423         json.writeNumberMember("__width__", width);
 424         json.writeNumberMember("__height__", height);
 425         json.writeNumberMember("__depth__", 1);
 426
 427         // Hardcoded for now, but we could chose types more adequate to the
 428         // texture internal format
 429         json.writeStringMember("__type__", "uint8");
 430         json.writeBoolMember("__normalized__", true);
 431         json.writeNumberMember("__channels__", channels);
 432
 433         GLubyte *pixels = new GLubyte[width*height*channels];
 434
 435         GLint drawbuffer = GL_NONE;
 436         GLint readbuffer = GL_NONE;
 437         glGetIntegerv(GL_DRAW_BUFFER, &drawbuffer);
 438         glGetIntegerv(GL_READ_BUFFER, &readbuffer);
 439         glReadBuffer(drawbuffer);
 440
 441         glPushClientAttrib(GL_CLIENT_PIXEL_STORE_BIT);
 442         glPixelStorei(GL_PACK_ALIGNMENT, 1);
 443
 444         glReadPixels(0, 0, width, height, format, GL_UNSIGNED_BYTE, pixels);
 445
 446         glPopClientAttrib();
 447         glReadBuffer(readbuffer);
 448
 449         json.beginMember("__data__");
 450         char *pngBuffer;
 451         int pngBufferSize;
 452         Image::writePixelsToBuffer(pixels, width, height, channels, false, &pngBuffer, &pngBufferSize);
 453         //std::cerr <<" Before = "<<(width * height * channels * sizeof *pixels)
 454         //          <<", after = "<<pngBufferSize << ", ratio = " << double(width * height * channels * sizeof *pixels)/pngBufferSize;
 455         json.writeBase64(pngBuffer, pngBufferSize);
 456         free(pngBuffer);
 457         json.endMember(); // __data__
 458
 459         delete [] pixels;
 460         json.endObject();
 461     }
 462 }
 463
 464
 465 static inline GLuint
 466 downsampledFramebuffer(GLuint oldFbo, GLint drawbuffer,
 467                        GLint colorRb, GLint depthRb, GLint stencilRb,
 468                        GLuint *rbs, GLint *numRbs)
 469 {
 470     GLuint fbo;
 471     GLint format;
 472     GLint w, h;
 473
 474     *numRbs = 0;
 475
 476     glGenFramebuffers(1, &fbo);
 477     glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 478
 479     glBindRenderbuffer(GL_RENDERBUFFER, colorRb);
 480     glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 481                                  GL_RENDERBUFFER_WIDTH, &w);
 482     glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 483                                  GL_RENDERBUFFER_HEIGHT, &h);
 484     glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 485                                  GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
 486
 487     glGenRenderbuffers(1, &rbs[*numRbs]);
 488     glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
 489     glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
 490     glFramebufferRenderbuffer(GL_FRAMEBUFFER, drawbuffer,
 491                               GL_RENDERBUFFER, rbs[*numRbs]);
 492
 493     glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
 494     glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
 495     glDrawBuffer(drawbuffer);
 496     glReadBuffer(drawbuffer);
 497     glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
 498                       GL_COLOR_BUFFER_BIT, GL_NEAREST);
 499     glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 500     ++*numRbs;
 501
 502     if (stencilRb == depthRb && stencilRb) {
 503         //combined depth and stencil buffer
 504         glBindRenderbuffer(GL_RENDERBUFFER, depthRb);
 505         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 506                                      GL_RENDERBUFFER_WIDTH, &w);
 507         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 508                                      GL_RENDERBUFFER_HEIGHT, &h);
 509         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 510                                      GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
 511
 512         glGenRenderbuffers(1, &rbs[*numRbs]);
 513         glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
 514         glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
 515         glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
 516                                   GL_RENDERBUFFER, rbs[*numRbs]);
 517         glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
 518         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
 519         glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
 520                           GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT, GL_NEAREST);
 521         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 522         ++*numRbs;
 523     } else {
 524         if (depthRb) {
 525             glBindRenderbuffer(GL_RENDERBUFFER, depthRb);
 526             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 527                                          GL_RENDERBUFFER_WIDTH, &w);
 528             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 529                                          GL_RENDERBUFFER_HEIGHT, &h);
 530             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 531                                          GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
 532
 533             glGenRenderbuffers(1, &rbs[*numRbs]);
 534             glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
 535             glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
 536             glFramebufferRenderbuffer(GL_FRAMEBUFFER,
 537                                       GL_DEPTH_ATTACHMENT,
 538                                       GL_RENDERBUFFER, rbs[*numRbs]);
 539             glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
 540             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
 541             glDrawBuffer(GL_DEPTH_ATTACHMENT);
 542             glReadBuffer(GL_DEPTH_ATTACHMENT);
 543             glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
 544                               GL_DEPTH_BUFFER_BIT, GL_NEAREST);
 545             ++*numRbs;
 546         }
 547         if (stencilRb) {
 548             glBindRenderbuffer(GL_RENDERBUFFER, stencilRb);
 549             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 550                                          GL_RENDERBUFFER_WIDTH, &w);
 551             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 552                                          GL_RENDERBUFFER_HEIGHT, &h);
 553             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 554                                      GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
 555
 556             glGenRenderbuffers(1, &rbs[*numRbs]);
 557             glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
 558             glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
 559             glFramebufferRenderbuffer(GL_FRAMEBUFFER,
 560                                       GL_STENCIL_ATTACHMENT,
 561                                       GL_RENDERBUFFER, rbs[*numRbs]);
 562             glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
 563             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
 564             glDrawBuffer(GL_STENCIL_ATTACHMENT);
 565             glReadBuffer(GL_STENCIL_ATTACHMENT);
 566             glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
 567                               GL_STENCIL_BUFFER_BIT, GL_NEAREST);
 568             ++*numRbs;
 569         }
 570     }
 571
 572     return fbo;
 573 }
 574
 575
 576 static void
 577 dumpDrawBuffers(JSONWriter &json, GLboolean dumpDepth, GLboolean dumpStencil)
 578 {
 579     json.beginMember("GL_RGBA");
 580     dumpDrawBufferImage(json, GL_RGBA);
 581     json.endMember();
 582
 583     if (dumpDepth) {
 584         json.beginMember("GL_DEPTH_COMPONENT");
 585         dumpDrawBufferImage(json, GL_DEPTH_COMPONENT);
 586         json.endMember();
 587     }
 588
 589     if (dumpStencil) {
 590         json.beginMember("GL_STENCIL_INDEX");
 591         dumpDrawBufferImage(json, GL_STENCIL_INDEX);
 592         json.endMember();
 593     }
 594 }
 595
 596
 597 static void
 598 dumpFramebuffer(JSONWriter &json)
 599 {
 600     json.beginMember("framebuffer");
 601     json.beginObject();
 602
 603     GLint boundDrawFbo = 0, boundReadFbo = 0;
 604     glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &boundDrawFbo);
 605     glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &boundReadFbo);
 606     if (!boundDrawFbo) {
 607         GLint depth_bits = 0;
 608         glGetIntegerv(GL_DEPTH_BITS, &depth_bits);
 609         GLint stencil_bits = 0;
 610         glGetIntegerv(GL_STENCIL_BITS, &stencil_bits);
 611         dumpDrawBuffers(json, depth_bits, stencil_bits);
 612     } else {
 613         GLint colorRb, stencilRb, depthRb;
 614         GLint boundRb;
 615         glGetIntegerv(GL_RENDERBUFFER_BINDING, &boundRb);
 616         GLint drawbuffer = GL_NONE;
 617         glGetIntegerv(GL_DRAW_BUFFER, &drawbuffer);
 618
 619         glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER,
 620                                               drawbuffer,
 621                                               GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
 622                                               &colorRb);
 623         glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER,
 624                                               GL_DEPTH_ATTACHMENT,
 625                                               GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
 626                                               &depthRb);
 627         glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER,
 628                                               GL_STENCIL_ATTACHMENT,
 629                                               GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
 630                                               &stencilRb);
 631
 632         GLint colorSamples, depthSamples, stencilSamples;
 633         GLuint rbs[3];
 634         GLint numRbs = 0;
 635         GLuint fboCopy = 0;
 636         glBindRenderbuffer(GL_RENDERBUFFER, colorRb);
 637         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 638                                      GL_RENDERBUFFER_SAMPLES, &colorSamples);
 639         glBindRenderbuffer(GL_RENDERBUFFER, depthRb);
 640         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 641                                      GL_RENDERBUFFER_SAMPLES, &depthSamples);
 642         glBindRenderbuffer(GL_RENDERBUFFER, stencilRb);
 643         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 644                                      GL_RENDERBUFFER_SAMPLES, &stencilSamples);
 645         glBindRenderbuffer(GL_RENDERBUFFER, boundRb);
 646
 647         if (colorSamples || depthSamples || stencilSamples) {
 648             //glReadPixels doesnt support multisampled buffers so we need
 649             // to blit the fbo to a temporary one
 650             fboCopy = downsampledFramebuffer(boundDrawFbo, drawbuffer,
 651                                              colorRb, depthRb, stencilRb,
 652                                              rbs, &numRbs);
 653         }
 654         glDrawBuffer(drawbuffer);
 655         glReadBuffer(drawbuffer);
 656
 657         dumpDrawBuffers(json, depthRb, stencilRb);
 658
 659         if (fboCopy) {
 660             glBindFramebuffer(GL_FRAMEBUFFER, boundDrawFbo);
 661             glBindFramebuffer(GL_READ_FRAMEBUFFER, boundReadFbo);
 662             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, boundDrawFbo);
 663             glBindRenderbuffer(GL_RENDERBUFFER_BINDING, boundRb);
 664             glDeleteRenderbuffers(numRbs, rbs);
 665             glDeleteFramebuffers(1, &fboCopy);
 666         }
 667     }
 668
 669     json.endObject();
 670     json.endMember(); // framebuffer
 671 }
 672
 673
 674 void dumpCurrentContext(std::ostream &os)
 675 {
 676     JSONWriter json(os);
 677     dumpParameters(json);
 678     dumpShaders(json);
 679     dumpTextures(json);
 680     dumpFramebuffer(json);
 681 }
 682
 683
 684 } /* namespace glstate */