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
  29 #include <algorithm>
  30 #include <iostream>
  31 #include <map>
  32 #include <sstream>
  33
  34 #include "image.hpp"
  35 #include "json.hpp"
  36 #include "glproc.hpp"
  37 #include "glsize.hpp"
  38 #include "glstate.hpp"
  39
  40
  41 #ifdef __APPLE__
  42
  43 #include <Carbon/Carbon.h>
  44
  45 #ifdef __cplusplus
  46 extern "C" {
  47 #endif
  48
  49 OSStatus CGSGetSurfaceBounds(CGSConnectionID, CGWindowID, CGSSurfaceID, CGRect *);
  50
  51 #ifdef __cplusplus
  52 }
  53 #endif
  54
  55 #endif /* __APPLE__ */
  56
  57
  58 namespace glstate {
  59
  60
  61 static inline void
  62 resetPixelPackState(void) {
  63     glPushClientAttrib(GL_CLIENT_PIXEL_STORE_BIT);
  64     glPixelStorei(GL_PACK_SWAP_BYTES, GL_FALSE);
  65     glPixelStorei(GL_PACK_LSB_FIRST, GL_FALSE);
  66     glPixelStorei(GL_PACK_ROW_LENGTH, 0);
  67     glPixelStorei(GL_PACK_IMAGE_HEIGHT, 0);
  68     glPixelStorei(GL_PACK_SKIP_ROWS, 0);
  69     glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
  70     glPixelStorei(GL_PACK_SKIP_IMAGES, 0);
  71     glPixelStorei(GL_PACK_ALIGNMENT, 1);
  72     glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
  73 }
  74
  75
  76 static inline void
  77 restorePixelPackState(void) {
  78     glPopClientAttrib();
  79 }
  80
  81
  82 // Mapping from shader type to shader source, used to accumulated the sources
  83 // of different shaders with same type.
  84 typedef std::map<std::string, std::string> ShaderMap;
  85
  86
  87 static void
  88 getShaderSource(ShaderMap &shaderMap, GLuint shader)
  89 {
  90     if (!shader) {
  91         return;
  92     }
  93
  94     GLint shader_type = 0;
  95     glGetShaderiv(shader, GL_SHADER_TYPE, &shader_type);
  96     if (!shader_type) {
  97         return;
  98     }
  99
 100     GLint source_length = 0;
 101     glGetShaderiv(shader, GL_SHADER_SOURCE_LENGTH, &source_length);
 102     if (!source_length) {
 103         return;
 104     }
 105
 106     GLchar *source = new GLchar[source_length];
 107     GLsizei length = 0;
 108     source[0] = 0;
 109     glGetShaderSource(shader, source_length, &length, source);
 110
 111     shaderMap[enumToString(shader_type)] += source;
 112
 113     delete [] source;
 114 }
 115
 116
 117 static void
 118 getShaderObjSource(ShaderMap &shaderMap, GLhandleARB shaderObj)
 119 {
 120     if (!shaderObj) {
 121         return;
 122     }
 123
 124     GLint object_type = 0;
 125     glGetObjectParameterivARB(shaderObj, GL_OBJECT_TYPE_ARB, &object_type);
 126     if (object_type != GL_SHADER_OBJECT_ARB) {
 127         return;
 128     }
 129
 130     GLint shader_type = 0;
 131     glGetObjectParameterivARB(shaderObj, GL_OBJECT_SUBTYPE_ARB, &shader_type);
 132     if (!shader_type) {
 133         return;
 134     }
 135
 136     GLint source_length = 0;
 137     glGetObjectParameterivARB(shaderObj, GL_OBJECT_SHADER_SOURCE_LENGTH_ARB, &source_length);
 138     if (!source_length) {
 139         return;
 140     }
 141
 142     GLcharARB *source = new GLcharARB[source_length];
 143     GLsizei length = 0;
 144     source[0] = 0;
 145     glGetShaderSource(shaderObj, source_length, &length, source);
 146
 147     shaderMap[enumToString(shader_type)] += source;
 148
 149     delete [] source;
 150 }
 151
 152
 153 static inline void
 154 dumpCurrentProgram(JSONWriter &json)
 155 {
 156     GLint program = 0;
 157     glGetIntegerv(GL_CURRENT_PROGRAM, &program);
 158     if (!program) {
 159         return;
 160     }
 161
 162     GLint attached_shaders = 0;
 163     glGetProgramiv(program, GL_ATTACHED_SHADERS, &attached_shaders);
 164     if (!attached_shaders) {
 165         return;
 166     }
 167
 168     ShaderMap shaderMap;
 169
 170     GLuint *shaders = new GLuint[attached_shaders];
 171     GLsizei count = 0;
 172     glGetAttachedShaders(program, attached_shaders, &count, shaders);
 173     std::sort(shaders, shaders + count);
 174     for (GLsizei i = 0; i < count; ++ i) {
 175        getShaderSource(shaderMap, shaders[i]);
 176     }
 177     delete [] shaders;
 178
 179     for (ShaderMap::const_iterator it = shaderMap.begin(); it != shaderMap.end(); ++it) {
 180         json.beginMember(it->first);
 181         json.writeString(it->second);
 182         json.endMember();
 183     }
 184 }
 185
 186
 187 static inline void
 188 dumpCurrentProgramObj(JSONWriter &json)
 189 {
 190     GLhandleARB programObj = glGetHandleARB(GL_PROGRAM_OBJECT_ARB);
 191     if (!programObj) {
 192         return;
 193     }
 194
 195     GLint attached_shaders = 0;
 196     glGetObjectParameterivARB(programObj, GL_OBJECT_ATTACHED_OBJECTS_ARB, &attached_shaders);
 197     if (!attached_shaders) {
 198         return;
 199     }
 200
 201     ShaderMap shaderMap;
 202
 203     GLhandleARB *shaderObjs = new GLhandleARB[attached_shaders];
 204     GLsizei count = 0;
 205     glGetAttachedObjectsARB(programObj, attached_shaders, &count, shaderObjs);
 206     std::sort(shaderObjs, shaderObjs + count);
 207     for (GLsizei i = 0; i < count; ++ i) {
 208        getShaderObjSource(shaderMap, shaderObjs[i]);
 209     }
 210     delete [] shaderObjs;
 211
 212     for (ShaderMap::const_iterator it = shaderMap.begin(); it != shaderMap.end(); ++it) {
 213         json.beginMember(it->first);
 214         json.writeString(it->second);
 215         json.endMember();
 216     }
 217 }
 218
 219
 220 static void
 221 dumpUniform(JSONWriter &json, GLint program, GLint size, GLenum type, const GLchar *name) {
 222
 223     GLenum elemType;
 224     GLint numElems;
 225     __gl_uniform_size(type, elemType, numElems);
 226     if (elemType == GL_NONE) {
 227         return;
 228     }
 229
 230     GLfloat fvalues[4*4];
 231     GLdouble dvalues[4*4];
 232     GLint ivalues[4*4];
 233     GLuint uivalues[4*4];
 234
 235     GLint i, j;
 236
 237     for (i = 0; i < size; ++i) {
 238         std::stringstream ss;
 239         ss << name;
 240
 241         if (size > 1) {
 242             ss << '[' << i << ']';
 243         }
 244
 245         std::string elemName = ss.str();
 246
 247         json.beginMember(elemName);
 248
 249         GLint location = glGetUniformLocation(program, elemName.c_str());
 250
 251         if (numElems > 1) {
 252             json.beginArray();
 253         }
 254
 255         switch (elemType) {
 256         case GL_FLOAT:
 257             glGetUniformfv(program, location, fvalues);
 258             for (j = 0; j < numElems; ++j) {
 259                 json.writeNumber(fvalues[j]);
 260             }
 261             break;
 262         case GL_DOUBLE:
 263             glGetUniformdv(program, location, dvalues);
 264             for (j = 0; j < numElems; ++j) {
 265                 json.writeNumber(dvalues[j]);
 266             }
 267             break;
 268         case GL_INT:
 269             glGetUniformiv(program, location, ivalues);
 270             for (j = 0; j < numElems; ++j) {
 271                 json.writeNumber(ivalues[j]);
 272             }
 273             break;
 274         case GL_UNSIGNED_INT:
 275             glGetUniformuiv(program, location, uivalues);
 276             for (j = 0; j < numElems; ++j) {
 277                 json.writeNumber(uivalues[j]);
 278             }
 279             break;
 280         case GL_BOOL:
 281             glGetUniformiv(program, location, ivalues);
 282             for (j = 0; j < numElems; ++j) {
 283                 json.writeBool(ivalues[j]);
 284             }
 285             break;
 286         default:
 287             assert(0);
 288             break;
 289         }
 290
 291         if (numElems > 1) {
 292             json.endArray();
 293         }
 294
 295         json.endMember();
 296     }
 297 }
 298
 299
 300 static void
 301 dumpUniformARB(JSONWriter &json, GLhandleARB programObj, GLint size, GLenum type, const GLchar *name) {
 302
 303     GLenum elemType;
 304     GLint numElems;
 305     __gl_uniform_size(type, elemType, numElems);
 306     if (elemType == GL_NONE) {
 307         return;
 308     }
 309
 310     GLfloat fvalues[4*4];
 311     GLint ivalues[4*4];
 312
 313     GLint i, j;
 314
 315     for (i = 0; i < size; ++i) {
 316         std::stringstream ss;
 317         ss << name;
 318
 319         if (size > 1) {
 320             ss << '[' << i << ']';
 321         }
 322
 323         std::string elemName = ss.str();
 324
 325         json.beginMember(elemName);
 326
 327         GLint location = glGetUniformLocationARB(programObj, elemName.c_str());
 328
 329         if (numElems > 1) {
 330             json.beginArray();
 331         }
 332
 333         switch (elemType) {
 334         case GL_DOUBLE:
 335             // glGetUniformdvARB does not exists
 336         case GL_FLOAT:
 337             glGetUniformfvARB(programObj, location, fvalues);
 338             for (j = 0; j < numElems; ++j) {
 339                 json.writeNumber(fvalues[j]);
 340             }
 341             break;
 342         case GL_UNSIGNED_INT:
 343             // glGetUniformuivARB does not exists
 344         case GL_INT:
 345             glGetUniformivARB(programObj, location, ivalues);
 346             for (j = 0; j < numElems; ++j) {
 347                 json.writeNumber(ivalues[j]);
 348             }
 349             break;
 350         case GL_BOOL:
 351             glGetUniformivARB(programObj, location, ivalues);
 352             for (j = 0; j < numElems; ++j) {
 353                 json.writeBool(ivalues[j]);
 354             }
 355             break;
 356         default:
 357             assert(0);
 358             break;
 359         }
 360
 361         if (numElems > 1) {
 362             json.endArray();
 363         }
 364
 365         json.endMember();
 366     }
 367 }
 368
 369
 370 static inline void
 371 dumpCurrentProgramUniforms(JSONWriter &json)
 372 {
 373     GLint program = 0;
 374     glGetIntegerv(GL_CURRENT_PROGRAM, &program);
 375     if (!program) {
 376         return;
 377     }
 378
 379     GLint active_uniforms = 0;
 380     glGetProgramiv(program, GL_ACTIVE_UNIFORMS, &active_uniforms);
 381     if (!active_uniforms) {
 382         return;
 383     }
 384
 385     GLint active_uniform_max_length = 0;
 386     glGetProgramiv(program, GL_ACTIVE_UNIFORM_MAX_LENGTH, &active_uniform_max_length);
 387     GLchar *name = new GLchar[active_uniform_max_length];
 388     if (!name) {
 389         return;
 390     }
 391
 392     for (GLint index = 0; index < active_uniforms; ++index) {
 393         GLsizei length = 0;
 394         GLint size = 0;
 395         GLenum type = GL_NONE;
 396         glGetActiveUniform(program, index, active_uniform_max_length, &length, &size, &type, name);
 397
 398         dumpUniform(json, program, size, type, name);
 399     }
 400
 401     delete [] name;
 402 }
 403
 404
 405 static inline void
 406 dumpCurrentProgramUniformsARB(JSONWriter &json)
 407 {
 408     GLhandleARB programObj = glGetHandleARB(GL_PROGRAM_OBJECT_ARB);
 409     if (!programObj) {
 410         return;
 411     }
 412
 413     GLint active_uniforms = 0;
 414     glGetObjectParameterivARB(programObj, GL_OBJECT_ACTIVE_UNIFORMS_ARB, &active_uniforms);
 415     if (!active_uniforms) {
 416         return;
 417     }
 418
 419     GLint active_uniform_max_length = 0;
 420     glGetObjectParameterivARB(programObj, GL_OBJECT_ACTIVE_UNIFORM_MAX_LENGTH_ARB, &active_uniform_max_length);
 421     GLchar *name = new GLchar[active_uniform_max_length];
 422     if (!name) {
 423         return;
 424     }
 425
 426     for (GLint index = 0; index < active_uniforms; ++index) {
 427         GLsizei length = 0;
 428         GLint size = 0;
 429         GLenum type = GL_NONE;
 430         glGetActiveUniformARB(programObj, index, active_uniform_max_length, &length, &size, &type, name);
 431
 432         dumpUniformARB(json, programObj, size, type, name);
 433     }
 434
 435     delete [] name;
 436 }
 437
 438
 439 static inline void
 440 dumpArbProgram(JSONWriter &json, GLenum target)
 441 {
 442     if (!glIsEnabled(target)) {
 443         return;
 444     }
 445
 446     GLint program_length = 0;
 447     glGetProgramivARB(target, GL_PROGRAM_LENGTH_ARB, &program_length);
 448     if (!program_length) {
 449         return;
 450     }
 451
 452     GLchar *source = new GLchar[program_length + 1];
 453     source[0] = 0;
 454     glGetProgramStringARB(target, GL_PROGRAM_STRING_ARB, source);
 455     source[program_length] = 0;
 456
 457     json.beginMember(enumToString(target));
 458     json.writeString(source);
 459     json.endMember();
 460
 461     delete [] source;
 462 }
 463
 464
 465 static inline void
 466 dumpProgramUniformsARB(JSONWriter &json, GLenum target, const char *prefix)
 467 {
 468     if (!glIsEnabled(target)) {
 469         return;
 470     }
 471
 472     GLint program_parameters = 0;
 473     glGetProgramivARB(target, GL_PROGRAM_PARAMETERS_ARB, &program_parameters);
 474     if (!program_parameters) {
 475         return;
 476     }
 477
 478     GLint max_program_local_parameters = 0;
 479     glGetProgramivARB(target, GL_MAX_PROGRAM_LOCAL_PARAMETERS_ARB, &max_program_local_parameters);
 480     for (GLuint index = 0; index < max_program_local_parameters; ++index) {
 481         GLdouble params[4] = {0, 0, 0, 0};
 482         glGetProgramLocalParameterdvARB(target, index, params);
 483
 484         if (!params[0] && !params[1] && !params[2] && !params[3]) {
 485             continue;
 486         }
 487
 488         char name[256];
 489         snprintf(name, sizeof name, "%sprogram.local[%u]", prefix, index);
 490
 491         json.beginMember(name);
 492         json.beginArray();
 493         json.writeNumber(params[0]);
 494         json.writeNumber(params[1]);
 495         json.writeNumber(params[2]);
 496         json.writeNumber(params[3]);
 497         json.endArray();
 498         json.endMember();
 499     }
 500
 501     GLint max_program_env_parameters = 0;
 502     glGetProgramivARB(target, GL_MAX_PROGRAM_ENV_PARAMETERS_ARB, &max_program_env_parameters);
 503     for (GLuint index = 0; index < max_program_env_parameters; ++index) {
 504         GLdouble params[4] = {0, 0, 0, 0};
 505         glGetProgramEnvParameterdvARB(target, index, params);
 506
 507         if (!params[0] && !params[1] && !params[2] && !params[3]) {
 508             continue;
 509         }
 510
 511         char name[256];
 512         snprintf(name, sizeof name, "%sprogram.env[%u]", prefix, index);
 513
 514         json.beginMember(name);
 515         json.beginArray();
 516         json.writeNumber(params[0]);
 517         json.writeNumber(params[1]);
 518         json.writeNumber(params[2]);
 519         json.writeNumber(params[3]);
 520         json.endArray();
 521         json.endMember();
 522     }
 523 }
 524
 525
 526 static inline void
 527 dumpShaders(JSONWriter &json)
 528 {
 529     json.beginMember("shaders");
 530     json.beginObject();
 531     dumpCurrentProgram(json);
 532     dumpCurrentProgramObj(json);
 533     dumpArbProgram(json, GL_FRAGMENT_PROGRAM_ARB);
 534     dumpArbProgram(json, GL_VERTEX_PROGRAM_ARB);
 535     json.endObject();
 536     json.endMember(); // shaders
 537 }
 538
 539
 540 static inline void
 541 dumpUniforms(JSONWriter &json)
 542 {
 543     json.beginMember("uniforms");
 544     json.beginObject();
 545     dumpCurrentProgramUniforms(json);
 546     dumpCurrentProgramUniformsARB(json);
 547     dumpProgramUniformsARB(json, GL_FRAGMENT_PROGRAM_ARB, "fp.");
 548     dumpProgramUniformsARB(json, GL_VERTEX_PROGRAM_ARB, "vp.");
 549     json.endObject();
 550     json.endMember(); // uniforms
 551 }
 552
 553
 554 static inline void
 555 dumpTextureImage(JSONWriter &json, GLenum target, GLint level)
 556 {
 557     GLint width, height = 1, depth = 1;
 558
 559     width = 0;
 560     glGetTexLevelParameteriv(target, level, GL_TEXTURE_WIDTH, &width);
 561
 562     if (target != GL_TEXTURE_1D) {
 563         height = 0;
 564         glGetTexLevelParameteriv(target, level, GL_TEXTURE_HEIGHT, &height);
 565         if (target == GL_TEXTURE_3D) {
 566             depth = 0;
 567             glGetTexLevelParameteriv(target, level, GL_TEXTURE_DEPTH, &depth);
 568         }
 569     }
 570
 571     if (width <= 0 || height <= 0 || depth <= 0) {
 572         return;
 573     } else {
 574         char label[512];
 575
 576         GLint active_texture = GL_TEXTURE0;
 577         glGetIntegerv(GL_ACTIVE_TEXTURE, &active_texture);
 578         snprintf(label, sizeof label, "%s, %s, level = %i", enumToString(active_texture), enumToString(target), level);
 579
 580         json.beginMember(label);
 581
 582         json.beginObject();
 583
 584         // Tell the GUI this is no ordinary object, but an image
 585         json.writeStringMember("__class__", "image");
 586
 587         json.writeNumberMember("__width__", width);
 588         json.writeNumberMember("__height__", height);
 589         json.writeNumberMember("__depth__", depth);
 590
 591         // Hardcoded for now, but we could chose types more adequate to the
 592         // texture internal format
 593         json.writeStringMember("__type__", "uint8");
 594         json.writeBoolMember("__normalized__", true);
 595         json.writeNumberMember("__channels__", 4);
 596
 597         GLubyte *pixels = new GLubyte[depth*width*height*4];
 598
 599         resetPixelPackState();
 600
 601         glGetTexImage(target, level, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
 602
 603         restorePixelPackState();
 604
 605         json.beginMember("__data__");
 606         char *pngBuffer;
 607         int pngBufferSize;
 608         Image::writePixelsToBuffer(pixels, width, height, 4, false, &pngBuffer, &pngBufferSize);
 609         json.writeBase64(pngBuffer, pngBufferSize);
 610         free(pngBuffer);
 611         json.endMember(); // __data__
 612
 613         delete [] pixels;
 614         json.endObject();
 615     }
 616 }
 617
 618
 619 static inline void
 620 dumpTexture(JSONWriter &json, GLenum target, GLenum binding)
 621 {
 622     GLint texture_binding = 0;
 623     glGetIntegerv(binding, &texture_binding);
 624     if (!glIsEnabled(target) && !texture_binding) {
 625         return;
 626     }
 627
 628     GLint level = 0;
 629     do {
 630         GLint width = 0, height = 0;
 631         glGetTexLevelParameteriv(target, level, GL_TEXTURE_WIDTH, &width);
 632         glGetTexLevelParameteriv(target, level, GL_TEXTURE_HEIGHT, &height);
 633         if (!width || !height) {
 634             break;
 635         }
 636
 637         if (target == GL_TEXTURE_CUBE_MAP) {
 638             for (int face = 0; face < 6; ++face) {
 639                 dumpTextureImage(json, GL_TEXTURE_CUBE_MAP_POSITIVE_X + face, level);
 640             }
 641         } else {
 642             dumpTextureImage(json, target, level);
 643         }
 644
 645         ++level;
 646     } while(true);
 647 }
 648
 649
 650 static inline void
 651 dumpTextures(JSONWriter &json)
 652 {
 653     json.beginMember("textures");
 654     json.beginObject();
 655     GLint active_texture = GL_TEXTURE0;
 656     glGetIntegerv(GL_ACTIVE_TEXTURE, &active_texture);
 657     GLint max_texture_coords = 0;
 658     glGetIntegerv(GL_MAX_TEXTURE_COORDS, &max_texture_coords);
 659     GLint max_combined_texture_image_units = 0;
 660     glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &max_combined_texture_image_units);
 661     GLint max_units = std::max(max_combined_texture_image_units, max_texture_coords);
 662     for (GLint unit = 0; unit < max_units; ++unit) {
 663         GLenum texture = GL_TEXTURE0 + unit;
 664         glActiveTexture(texture);
 665         dumpTexture(json, GL_TEXTURE_1D, GL_TEXTURE_BINDING_1D);
 666         dumpTexture(json, GL_TEXTURE_2D, GL_TEXTURE_BINDING_2D);
 667         dumpTexture(json, GL_TEXTURE_3D, GL_TEXTURE_BINDING_3D);
 668         dumpTexture(json, GL_TEXTURE_RECTANGLE, GL_TEXTURE_BINDING_RECTANGLE);
 669         dumpTexture(json, GL_TEXTURE_CUBE_MAP, GL_TEXTURE_BINDING_CUBE_MAP);
 670     }
 671     glActiveTexture(active_texture);
 672     json.endObject();
 673     json.endMember(); // textures
 674 }
 675
 676
 677 static bool
 678 getDrawableBounds(GLint *width, GLint *height) {
 679 #if defined(_WIN32)
 680
 681     HDC hDC = wglGetCurrentDC();
 682     if (!hDC) {
 683         return false;
 684     }
 685
 686     HWND hWnd = WindowFromDC(hDC);
 687     RECT rect;
 688
 689     if (!GetClientRect(hWnd, &rect)) {
 690        return false;
 691     }
 692
 693     *width  = rect.right  - rect.left;
 694     *height = rect.bottom - rect.top;
 695
 696 #elif defined(__APPLE__)
 697
 698     CGLContextObj ctx = CGLGetCurrentContext();
 699     if (ctx == NULL) {
 700         return false;
 701     }
 702
 703     CGSConnectionID cid;
 704     CGSWindowID wid;
 705     CGSSurfaceID sid;
 706
 707     if (CGLGetSurface(ctx, &cid, &wid, &sid) != kCGLNoError) {
 708         return false;
 709     }
 710
 711     CGRect rect;
 712
 713     if (CGSGetSurfaceBounds(cid, wid, sid, &rect) != 0) {
 714         return false;
 715     }
 716
 717     *width = rect.size.width;
 718     *height = rect.size.height;
 719
 720 #else
 721
 722     Display *display;
 723     Drawable drawable;
 724     Window root;
 725     int x, y;
 726     unsigned int w, h, bw, depth;
 727
 728     display = glXGetCurrentDisplay();
 729     if (!display) {
 730         return false;
 731     }
 732
 733     drawable = glXGetCurrentDrawable();
 734     if (drawable == None) {
 735         return false;
 736     }
 737
 738     if (!XGetGeometry(display, drawable, &root, &x, &y, &w, &h, &bw, &depth)) {
 739         return false;
 740     }
 741
 742     *width = w;
 743     *height = h;
 744
 745 #endif
 746
 747     return true;
 748 }
 749
 750
 751 static const GLenum texture_bindings[][2] = {
 752     {GL_TEXTURE_1D, GL_TEXTURE_BINDING_1D},
 753     {GL_TEXTURE_2D, GL_TEXTURE_BINDING_2D},
 754     {GL_TEXTURE_3D, GL_TEXTURE_BINDING_3D},
 755     {GL_TEXTURE_RECTANGLE, GL_TEXTURE_BINDING_RECTANGLE},
 756     {GL_TEXTURE_CUBE_MAP, GL_TEXTURE_BINDING_CUBE_MAP}
 757 };
 758
 759
 760 static bool
 761 bindTexture(GLint texture, GLenum &target, GLint &bound_texture)
 762 {
 763
 764     for (unsigned i = 0; i < sizeof(texture_bindings)/sizeof(texture_bindings[0]); ++i) {
 765         target  = texture_bindings[i][0];
 766
 767         GLenum binding = texture_bindings[i][1];
 768
 769         while (glGetError() != GL_NO_ERROR)
 770             ;
 771
 772         glGetIntegerv(binding, &bound_texture);
 773         glBindTexture(target, texture);
 774
 775         if (glGetError() == GL_NO_ERROR) {
 776             return true;
 777         }
 778
 779         glBindTexture(target, bound_texture);
 780     }
 781
 782     target = GL_NONE;
 783
 784     return false;
 785 }
 786
 787
 788 static bool
 789 getTextureLevelSize(GLint texture, GLint level, GLint *width, GLint *height)
 790 {
 791     *width = 0;
 792     *height = 0;
 793
 794     GLenum target;
 795     GLint bound_texture = 0;
 796     if (!bindTexture(texture, target, bound_texture)) {
 797         return false;
 798     }
 799
 800     glGetTexLevelParameteriv(target, level, GL_TEXTURE_WIDTH, width);
 801     glGetTexLevelParameteriv(target, level, GL_TEXTURE_HEIGHT, height);
 802
 803     glBindTexture(target, bound_texture);
 804
 805     return *width > 0 && *height > 0;
 806 }
 807
 808
 809 static bool
 810 getRenderbufferSize(GLint renderbuffer, GLint *width, GLint *height)
 811 {
 812     GLint bound_renderbuffer = 0;
 813     glGetIntegerv(GL_RENDERBUFFER_BINDING, &bound_renderbuffer);
 814     glBindRenderbuffer(GL_RENDERBUFFER, renderbuffer);
 815
 816     *width = 0;
 817     *height = 0;
 818     glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, width);
 819     glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, height);
 820
 821     glBindRenderbuffer(GL_RENDERBUFFER, bound_renderbuffer);
 822
 823     return *width > 0 && *height > 0;
 824 }
 825
 826
 827 static bool
 828 getFramebufferAttachmentSize(GLenum target, GLenum attachment, GLint *width, GLint *height)
 829 {
 830     GLint object_type = GL_NONE;
 831     glGetFramebufferAttachmentParameteriv(target, attachment,
 832                                           GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE,
 833                                           &object_type);
 834     if (object_type == GL_NONE) {
 835         return false;
 836     }
 837
 838     GLint object_name = 0;
 839     glGetFramebufferAttachmentParameteriv(target, attachment,
 840                                           GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
 841                                           &object_name);
 842     if (object_name == 0) {
 843         return false;
 844     }
 845
 846     if (object_type == GL_RENDERBUFFER) {
 847         return getRenderbufferSize(object_name, width, height);
 848     } else if (object_type == GL_TEXTURE) {
 849         GLint texture_level = 0;
 850         glGetFramebufferAttachmentParameteriv(target, attachment,
 851                                               GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL,
 852                                               &texture_level);
 853         return getTextureLevelSize(object_name, texture_level, width, height);
 854     } else {
 855         std::cerr << "warning: unexpected GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE = " << object_type << "\n";
 856         return false;
 857     }
 858 }
 859
 860
 861 Image::Image *
 862 getDrawBufferImage(GLenum format) {
 863     GLint channels = __gl_format_channels(format);
 864     if (channels > 4) {
 865         return NULL;
 866     }
 867
 868     GLint draw_framebuffer = 0;
 869     glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &draw_framebuffer);
 870
 871     GLint draw_buffer = GL_NONE;
 872     GLint width, height;
 873     if (draw_framebuffer) {
 874         glGetIntegerv(GL_DRAW_BUFFER0, &draw_buffer);
 875         if (draw_buffer == GL_NONE) {
 876             return NULL;
 877         }
 878
 879         if (!getFramebufferAttachmentSize(GL_DRAW_FRAMEBUFFER, draw_buffer, &width, &height)) {
 880             return NULL;
 881         }
 882     } else {
 883         glGetIntegerv(GL_DRAW_BUFFER, &draw_buffer);
 884         if (draw_buffer == GL_NONE) {
 885             return NULL;
 886         }
 887
 888         if (!getDrawableBounds(&width, &height)) {
 889             return NULL;
 890         }
 891     }
 892
 893     Image::Image *image = new Image::Image(width, height, channels, true);
 894     if (!image) {
 895         return NULL;
 896     }
 897
 898     while (glGetError() != GL_NO_ERROR) {}
 899
 900     GLint read_framebuffer = 0;
 901     glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &read_framebuffer);
 902     glBindFramebuffer(GL_READ_FRAMEBUFFER, draw_framebuffer);
 903
 904     GLint read_buffer = 0;
 905     glGetIntegerv(GL_READ_BUFFER, &read_buffer);
 906     glReadBuffer(draw_buffer);
 907
 908     // TODO: reset imaging state too
 909     resetPixelPackState();
 910
 911     glReadPixels(0, 0, width, height, format, GL_UNSIGNED_BYTE, image->pixels);
 912
 913     restorePixelPackState();
 914     glReadBuffer(read_buffer);
 915     glBindFramebuffer(GL_READ_FRAMEBUFFER, read_framebuffer);
 916
 917     GLenum error = glGetError();
 918     if (error != GL_NO_ERROR) {
 919         do {
 920             std::cerr << "warning: " << enumToString(error) << " while getting snapshot\n";
 921             error = glGetError();
 922         } while(error != GL_NO_ERROR);
 923         delete image;
 924         return NULL;
 925     }
 926
 927     return image;
 928 }
 929
 930
 931 /**
 932  * Dump the image of the currently bound read buffer.
 933  */
 934 static inline void
 935 dumpReadBufferImage(JSONWriter &json, GLint width, GLint height, GLenum format)
 936 {
 937     GLint channels = __gl_format_channels(format);
 938
 939     json.beginObject();
 940
 941     // Tell the GUI this is no ordinary object, but an image
 942     json.writeStringMember("__class__", "image");
 943
 944     json.writeNumberMember("__width__", width);
 945     json.writeNumberMember("__height__", height);
 946     json.writeNumberMember("__depth__", 1);
 947
 948     // Hardcoded for now, but we could chose types more adequate to the
 949     // texture internal format
 950     json.writeStringMember("__type__", "uint8");
 951     json.writeBoolMember("__normalized__", true);
 952     json.writeNumberMember("__channels__", channels);
 953
 954     GLubyte *pixels = new GLubyte[width*height*channels];
 955
 956     // TODO: reset imaging state too
 957     resetPixelPackState();
 958
 959     glReadPixels(0, 0, width, height, format, GL_UNSIGNED_BYTE, pixels);
 960
 961     restorePixelPackState();
 962
 963     json.beginMember("__data__");
 964     char *pngBuffer;
 965     int pngBufferSize;
 966     Image::writePixelsToBuffer(pixels, width, height, channels, false, &pngBuffer, &pngBufferSize);
 967     //std::cerr <<" Before = "<<(width * height * channels * sizeof *pixels)
 968     //          <<", after = "<<pngBufferSize << ", ratio = " << double(width * height * channels * sizeof *pixels)/pngBufferSize;
 969     json.writeBase64(pngBuffer, pngBufferSize);
 970     free(pngBuffer);
 971     json.endMember(); // __data__
 972
 973     delete [] pixels;
 974     json.endObject();
 975 }
 976
 977
 978 static inline GLuint
 979 downsampledFramebuffer(GLuint oldFbo, GLint drawbuffer,
 980                        GLint colorRb, GLint depthRb, GLint stencilRb,
 981                        GLuint *rbs, GLint *numRbs)
 982 {
 983     GLuint fbo;
 984     GLint format;
 985     GLint w, h;
 986
 987     *numRbs = 0;
 988
 989     glGenFramebuffers(1, &fbo);
 990     glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 991
 992     glBindRenderbuffer(GL_RENDERBUFFER, colorRb);
 993     glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 994                                  GL_RENDERBUFFER_WIDTH, &w);
 995     glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 996                                  GL_RENDERBUFFER_HEIGHT, &h);
 997     glGetRenderbufferParameteriv(GL_RENDERBUFFER,
 998                                  GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
 999
1000     glGenRenderbuffers(1, &rbs[*numRbs]);
1001     glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
1002     glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
1003     glFramebufferRenderbuffer(GL_FRAMEBUFFER, drawbuffer,
1004                               GL_RENDERBUFFER, rbs[*numRbs]);
1005
1006     glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
1007     glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
1008     glDrawBuffer(drawbuffer);
1009     glReadBuffer(drawbuffer);
1010     glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
1011                       GL_COLOR_BUFFER_BIT, GL_NEAREST);
1012     glBindFramebuffer(GL_FRAMEBUFFER, fbo);
1013     ++*numRbs;
1014
1015     if (stencilRb == depthRb && stencilRb) {
1016         //combined depth and stencil buffer
1017         glBindRenderbuffer(GL_RENDERBUFFER, depthRb);
1018         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1019                                      GL_RENDERBUFFER_WIDTH, &w);
1020         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1021                                      GL_RENDERBUFFER_HEIGHT, &h);
1022         glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1023                                      GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
1024
1025         glGenRenderbuffers(1, &rbs[*numRbs]);
1026         glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
1027         glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
1028         glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
1029                                   GL_RENDERBUFFER, rbs[*numRbs]);
1030         glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
1031         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
1032         glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
1033                           GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT, GL_NEAREST);
1034         glBindFramebuffer(GL_FRAMEBUFFER, fbo);
1035         ++*numRbs;
1036     } else {
1037         if (depthRb) {
1038             glBindRenderbuffer(GL_RENDERBUFFER, depthRb);
1039             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1040                                          GL_RENDERBUFFER_WIDTH, &w);
1041             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1042                                          GL_RENDERBUFFER_HEIGHT, &h);
1043             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1044                                          GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
1045
1046             glGenRenderbuffers(1, &rbs[*numRbs]);
1047             glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
1048             glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
1049             glFramebufferRenderbuffer(GL_FRAMEBUFFER,
1050                                       GL_DEPTH_ATTACHMENT,
1051                                       GL_RENDERBUFFER, rbs[*numRbs]);
1052             glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
1053             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
1054             glDrawBuffer(GL_DEPTH_ATTACHMENT);
1055             glReadBuffer(GL_DEPTH_ATTACHMENT);
1056             glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
1057                               GL_DEPTH_BUFFER_BIT, GL_NEAREST);
1058             ++*numRbs;
1059         }
1060         if (stencilRb) {
1061             glBindRenderbuffer(GL_RENDERBUFFER, stencilRb);
1062             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1063                                          GL_RENDERBUFFER_WIDTH, &w);
1064             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1065                                          GL_RENDERBUFFER_HEIGHT, &h);
1066             glGetRenderbufferParameteriv(GL_RENDERBUFFER,
1067                                      GL_RENDERBUFFER_INTERNAL_FORMAT, &format);
1068
1069             glGenRenderbuffers(1, &rbs[*numRbs]);
1070             glBindRenderbuffer(GL_RENDERBUFFER, rbs[*numRbs]);
1071             glRenderbufferStorage(GL_RENDERBUFFER, format, w, h);
1072             glFramebufferRenderbuffer(GL_FRAMEBUFFER,
1073                                       GL_STENCIL_ATTACHMENT,
1074                                       GL_RENDERBUFFER, rbs[*numRbs]);
1075             glBindFramebuffer(GL_READ_FRAMEBUFFER, oldFbo);
1076             glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
1077             glDrawBuffer(GL_STENCIL_ATTACHMENT);
1078             glReadBuffer(GL_STENCIL_ATTACHMENT);
1079             glBlitFramebuffer(0, 0, w, h, 0, 0, w, h,
1080                               GL_STENCIL_BUFFER_BIT, GL_NEAREST);
1081             ++*numRbs;
1082         }
1083     }
1084
1085     return fbo;
1086 }
1087
1088
1089 /**
1090  * Dump images of current draw drawable/window.
1091  */
1092 static void
1093 dumpDrawableImages(JSONWriter &json)
1094 {
1095     GLint width, height;
1096
1097     if (!getDrawableBounds(&width, &height)) {
1098         return;
1099     }
1100
1101     GLint draw_buffer = GL_NONE;
1102     glGetIntegerv(GL_DRAW_BUFFER, &draw_buffer);
1103     glReadBuffer(draw_buffer);
1104
1105     if (draw_buffer != GL_NONE) {
1106         GLint read_buffer = GL_NONE;
1107         glGetIntegerv(GL_READ_BUFFER, &read_buffer);
1108
1109         GLint alpha_bits = 0;
1110         glGetIntegerv(GL_ALPHA_BITS, &alpha_bits);
1111         GLenum format = alpha_bits ? GL_RGBA : GL_RGB;
1112         json.beginMember(enumToString(draw_buffer));
1113         dumpReadBufferImage(json, width, height, format);
1114         json.endMember();
1115
1116         glReadBuffer(read_buffer);
1117     }
1118
1119     GLint depth_bits = 0;
1120     glGetIntegerv(GL_DEPTH_BITS, &depth_bits);
1121     if (depth_bits) {
1122         json.beginMember("GL_DEPTH_COMPONENT");
1123         dumpReadBufferImage(json, width, height, GL_DEPTH_COMPONENT);
1124         json.endMember();
1125     }
1126
1127     GLint stencil_bits = 0;
1128     glGetIntegerv(GL_STENCIL_BITS, &stencil_bits);
1129     if (stencil_bits) {
1130         json.beginMember("GL_STENCIL_INDEX");
1131         dumpReadBufferImage(json, width, height, GL_STENCIL_INDEX);
1132         json.endMember();
1133     }
1134 }
1135 /**
1136  * Dump the specified framebuffer attachment.
1137  *
1138  * In the case of a color attachment, it assumes it is already bound for read.
1139  */
1140 static void
1141 dumpFramebufferAttachment(JSONWriter &json, GLenum target, GLenum attachment, GLenum format)
1142 {
1143     GLint width = 0, height = 0;
1144     if (!getFramebufferAttachmentSize(target, attachment, &width, &height)) {
1145         return;
1146     }
1147
1148     json.beginMember(enumToString(attachment));
1149     dumpReadBufferImage(json, width, height, format);
1150     json.endMember();
1151 }
1152
1153
1154 static void
1155 dumpFramebufferAttachments(JSONWriter &json, GLenum target)
1156 {
1157     GLint read_framebuffer = 0;
1158     glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &read_framebuffer);
1159
1160     GLint read_buffer = GL_NONE;
1161     glGetIntegerv(GL_READ_BUFFER, &read_buffer);
1162
1163     GLint max_draw_buffers = 1;
1164     glGetIntegerv(GL_MAX_DRAW_BUFFERS, &max_draw_buffers);
1165     GLint max_color_attachments = 0;
1166     glGetIntegerv(GL_MAX_COLOR_ATTACHMENTS, &max_color_attachments);
1167
1168     for (GLint i = 0; i < max_draw_buffers; ++i) {
1169         GLint draw_buffer = GL_NONE;
1170         glGetIntegerv(GL_DRAW_BUFFER0 + i, &draw_buffer);
1171         if (draw_buffer != GL_NONE) {
1172             glReadBuffer(draw_buffer);
1173             GLint attachment;
1174             if (draw_buffer >= GL_COLOR_ATTACHMENT0 && draw_buffer < GL_COLOR_ATTACHMENT0 + max_color_attachments) {
1175                 attachment = draw_buffer;
1176             } else {
1177                 std::cerr << "warning: unexpected GL_DRAW_BUFFER" << i << " = " << draw_buffer << "\n";
1178                 attachment = GL_COLOR_ATTACHMENT0;
1179             }
1180             GLint alpha_size = 0;
1181             glGetFramebufferAttachmentParameteriv(target, attachment,
1182                                                   GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE,
1183                                                   &alpha_size);
1184             GLenum format = alpha_size ? GL_RGBA : GL_RGB;
1185             dumpFramebufferAttachment(json, target, attachment, format);
1186         }
1187     }
1188
1189     glReadBuffer(read_buffer);
1190
1191     dumpFramebufferAttachment(json, target, GL_DEPTH_ATTACHMENT, GL_DEPTH_COMPONENT);
1192     dumpFramebufferAttachment(json, target, GL_STENCIL_ATTACHMENT, GL_STENCIL_INDEX);
1193
1194     glBindFramebuffer(GL_READ_FRAMEBUFFER, read_framebuffer);
1195 }
1196
1197
1198 static void
1199 dumpFramebuffer(JSONWriter &json)
1200 {
1201     json.beginMember("framebuffer");
1202     json.beginObject();
1203
1204     GLint boundDrawFbo = 0, boundReadFbo = 0;
1205     glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &boundDrawFbo);
1206     glGetIntegerv(GL_READ_FRAMEBUFFER_BINDING, &boundReadFbo);
1207     if (!boundDrawFbo) {
1208         dumpDrawableImages(json);
1209     } else {
1210         GLint colorRb = 0, stencilRb = 0, depthRb = 0;
1211         GLint draw_buffer0 = GL_NONE;
1212         glGetIntegerv(GL_DRAW_BUFFER0, &draw_buffer0);
1213         bool multisample = false;
1214
1215         GLint boundRb = 0;
1216         glGetIntegerv(GL_RENDERBUFFER_BINDING, &boundRb);
1217
1218         GLint object_type;
1219         glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, draw_buffer0, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &object_type);
1220         if (object_type == GL_RENDERBUFFER) {
1221             glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, draw_buffer0, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, &colorRb);
1222             glBindRenderbuffer(GL_RENDERBUFFER, colorRb);
1223             GLint samples = 0;
1224             glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_SAMPLES, &samples);
1225             if (samples) {
1226                 multisample = true;
1227             }
1228         }
1229
1230         glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &object_type);
1231         if (object_type == GL_RENDERBUFFER) {
1232             glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, &depthRb);
1233             glBindRenderbuffer(GL_RENDERBUFFER, depthRb);
1234             GLint samples = 0;
1235             glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_SAMPLES, &samples);
1236             if (samples) {
1237                 multisample = true;
1238             }
1239         }
1240
1241         glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &object_type);
1242         if (object_type == GL_RENDERBUFFER) {
1243             glGetFramebufferAttachmentParameteriv(GL_DRAW_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, &stencilRb);
1244             glBindRenderbuffer(GL_RENDERBUFFER, stencilRb);
1245             GLint samples = 0;
1246             glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_SAMPLES, &samples);
1247             if (samples) {
1248                 multisample = true;
1249             }
1250         }
1251
1252         glBindRenderbuffer(GL_RENDERBUFFER, boundRb);
1253
1254         GLuint rbs[3];
1255         GLint numRbs = 0;
1256         GLuint fboCopy = 0;
1257
1258         if (multisample) {
1259             // glReadPixels doesnt support multisampled buffers so we need
1260             // to blit the fbo to a temporary one
1261             fboCopy = downsampledFramebuffer(boundDrawFbo, draw_buffer0,
1262                                              colorRb, depthRb, stencilRb,
1263                                              rbs, &numRbs);
1264         }
1265
1266         dumpFramebufferAttachments(json, GL_DRAW_FRAMEBUFFER);
1267
1268         if (multisample) {
1269             glBindRenderbuffer(GL_RENDERBUFFER_BINDING, boundRb);
1270             glDeleteRenderbuffers(numRbs, rbs);
1271             glDeleteFramebuffers(1, &fboCopy);
1272         }
1273
1274         glBindFramebuffer(GL_READ_FRAMEBUFFER, boundReadFbo);
1275         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, boundDrawFbo);
1276     }
1277
1278     json.endObject();
1279     json.endMember(); // framebuffer
1280 }
1281
1282
1283 static const GLenum bindings[] = {
1284     GL_DRAW_BUFFER,
1285     GL_READ_BUFFER,
1286     GL_PIXEL_PACK_BUFFER_BINDING,
1287     GL_PIXEL_UNPACK_BUFFER_BINDING,
1288     GL_TEXTURE_BINDING_1D,
1289     GL_TEXTURE_BINDING_2D,
1290     GL_TEXTURE_BINDING_3D,
1291     GL_TEXTURE_BINDING_RECTANGLE,
1292     GL_TEXTURE_BINDING_CUBE_MAP,
1293     GL_DRAW_FRAMEBUFFER_BINDING,
1294     GL_READ_FRAMEBUFFER_BINDING,
1295     GL_RENDERBUFFER_BINDING,
1296     GL_DRAW_BUFFER0,
1297     GL_DRAW_BUFFER1,
1298     GL_DRAW_BUFFER2,
1299     GL_DRAW_BUFFER3,
1300     GL_DRAW_BUFFER4,
1301     GL_DRAW_BUFFER5,
1302     GL_DRAW_BUFFER6,
1303     GL_DRAW_BUFFER7,
1304 };
1305
1306
1307 #define NUM_BINDINGS sizeof(bindings)/sizeof(bindings[0])
1308
1309
1310 void dumpCurrentContext(std::ostream &os)
1311 {
1312     JSONWriter json(os);
1313
1314 #ifndef NDEBUG
1315     GLint old_bindings[NUM_BINDINGS];
1316     for (unsigned i = 0; i < NUM_BINDINGS; ++i) {
1317         old_bindings[i] = 0;
1318         glGetIntegerv(bindings[i], &old_bindings[i]);
1319     }
1320 #endif
1321
1322     dumpParameters(json);
1323     dumpShaders(json);
1324     dumpUniforms(json);
1325     dumpTextures(json);
1326     dumpFramebuffer(json);
1327
1328 #ifndef NDEBUG
1329     for (unsigned i = 0; i < NUM_BINDINGS; ++i) {
1330         GLint new_binding = 0;
1331         glGetIntegerv(bindings[i], &new_binding);
1332         if (new_binding != old_bindings[i]) {
1333             std::cerr << "warning: " << enumToString(bindings[i]) << " was clobbered\n";
1334         }
1335     }
1336 #endif
1337
1338 }
1339
1340
1341 } /* namespace glstate */