gpu/command_buffer/common/gles2_cmd_utils.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // This file is here so other GLES2 related files can have a common set of
   6 // includes where appropriate.
   7
   8 #include <sstream>
   9 #include <GLES2/gl2.h>
  10 #include <GLES2/gl2ext.h>
  11 #include <GLES2/gl2extchromium.h>
  12 #include <GLES3/gl3.h>
  13
  14 #include "base/numerics/safe_math.h"
  15 #include "gpu/command_buffer/common/gles2_cmd_format.h"
  16 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
  17
  18 namespace gpu {
  19 namespace gles2 {
  20
  21 namespace gl_error_bit {
  22 enum GLErrorBit {
  23   kNoError = 0,
  24   kInvalidEnum = (1 << 0),
  25   kInvalidValue = (1 << 1),
  26   kInvalidOperation = (1 << 2),
  27   kOutOfMemory = (1 << 3),
  28   kInvalidFrameBufferOperation = (1 << 4),
  29   kContextLost = (1 << 5)
  30 };
  31 }
  32
  33 int GLES2Util::GLGetNumValuesReturned(int id) const {
  34   switch (id) {
  35     // -- glGetBooleanv, glGetFloatv, glGetIntergerv
  36     case GL_ACTIVE_TEXTURE:
  37       return 1;
  38     case GL_ALIASED_LINE_WIDTH_RANGE:
  39       return 2;
  40     case GL_ALIASED_POINT_SIZE_RANGE:
  41       return 2;
  42     case GL_ALPHA_BITS:
  43       return 1;
  44     case GL_ARRAY_BUFFER_BINDING:
  45       return 1;
  46     case GL_BLEND:
  47       return 1;
  48     case GL_BLEND_COLOR:
  49       return 4;
  50     case GL_BLEND_DST_ALPHA:
  51       return 1;
  52     case GL_BLEND_DST_RGB:
  53       return 1;
  54     case GL_BLEND_EQUATION_ALPHA:
  55       return 1;
  56     case GL_BLEND_EQUATION_RGB:
  57       return 1;
  58     case GL_BLEND_SRC_ALPHA:
  59       return 1;
  60     case GL_BLEND_SRC_RGB:
  61       return 1;
  62     case GL_BLUE_BITS:
  63       return 1;
  64     case GL_COLOR_CLEAR_VALUE:
  65       return 4;
  66     case GL_COLOR_WRITEMASK:
  67       return 4;
  68     case GL_COMPRESSED_TEXTURE_FORMATS:
  69       return num_compressed_texture_formats_;
  70     case GL_CULL_FACE:
  71       return 1;
  72     case GL_CULL_FACE_MODE:
  73       return 1;
  74     case GL_CURRENT_PROGRAM:
  75       return 1;
  76     case GL_DEPTH_BITS:
  77       return 1;
  78     case GL_DEPTH_CLEAR_VALUE:
  79       return 1;
  80     case GL_DEPTH_FUNC:
  81       return 1;
  82     case GL_DEPTH_RANGE:
  83       return 2;
  84     case GL_DEPTH_TEST:
  85       return 1;
  86     case GL_DEPTH_WRITEMASK:
  87       return 1;
  88     case GL_DITHER:
  89       return 1;
  90     case GL_ELEMENT_ARRAY_BUFFER_BINDING:
  91       return 1;
  92     case GL_FRAMEBUFFER_BINDING:
  93       return 1;
  94     case GL_FRONT_FACE:
  95       return 1;
  96     case GL_GENERATE_MIPMAP_HINT:
  97       return 1;
  98     case GL_GREEN_BITS:
  99       return 1;
 100     case GL_IMPLEMENTATION_COLOR_READ_FORMAT:
 101       return 1;
 102     case GL_IMPLEMENTATION_COLOR_READ_TYPE:
 103       return 1;
 104     case GL_LINE_WIDTH:
 105       return 1;
 106     case GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS:
 107       return 1;
 108     case GL_MAX_CUBE_MAP_TEXTURE_SIZE:
 109       return 1;
 110     case GL_MAX_FRAGMENT_UNIFORM_VECTORS:
 111       return 1;
 112     case GL_MAX_RENDERBUFFER_SIZE:
 113       return 1;
 114     case GL_MAX_TEXTURE_IMAGE_UNITS:
 115       return 1;
 116     case GL_MAX_TEXTURE_SIZE:
 117       return 1;
 118     case GL_MAX_VARYING_VECTORS:
 119       return 1;
 120     case GL_MAX_VERTEX_ATTRIBS:
 121       return 1;
 122     case GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS:
 123       return 1;
 124     case GL_MAX_VERTEX_UNIFORM_VECTORS:
 125       return 1;
 126     case GL_MAX_VIEWPORT_DIMS:
 127       return 2;
 128     case GL_NUM_COMPRESSED_TEXTURE_FORMATS:
 129       return 1;
 130     case GL_NUM_SHADER_BINARY_FORMATS:
 131       return 1;
 132     case GL_PACK_ALIGNMENT:
 133       return 1;
 134     case GL_PACK_REVERSE_ROW_ORDER_ANGLE:
 135       return 1;
 136     case GL_POLYGON_OFFSET_FACTOR:
 137       return 1;
 138     case GL_POLYGON_OFFSET_FILL:
 139       return 1;
 140     case GL_POLYGON_OFFSET_UNITS:
 141       return 1;
 142     case GL_RED_BITS:
 143       return 1;
 144     case GL_RENDERBUFFER_BINDING:
 145       return 1;
 146     case GL_SAMPLE_BUFFERS:
 147       return 1;
 148     case GL_SAMPLE_COVERAGE_INVERT:
 149       return 1;
 150     case GL_SAMPLE_COVERAGE_VALUE:
 151       return 1;
 152     case GL_SAMPLES:
 153       return 1;
 154     case GL_SCISSOR_BOX:
 155       return 4;
 156     case GL_SCISSOR_TEST:
 157       return 1;
 158     case GL_SHADER_BINARY_FORMATS:
 159       return num_shader_binary_formats_;
 160     case GL_SHADER_COMPILER:
 161       return 1;
 162     case GL_STENCIL_BACK_FAIL:
 163       return 1;
 164     case GL_STENCIL_BACK_FUNC:
 165       return 1;
 166     case GL_STENCIL_BACK_PASS_DEPTH_FAIL:
 167       return 1;
 168     case GL_STENCIL_BACK_PASS_DEPTH_PASS:
 169       return 1;
 170     case GL_STENCIL_BACK_REF:
 171       return 1;
 172     case GL_STENCIL_BACK_VALUE_MASK:
 173       return 1;
 174     case GL_STENCIL_BACK_WRITEMASK:
 175       return 1;
 176     case GL_STENCIL_BITS:
 177       return 1;
 178     case GL_STENCIL_CLEAR_VALUE:
 179       return 1;
 180     case GL_STENCIL_FAIL:
 181       return 1;
 182     case GL_STENCIL_FUNC:
 183       return 1;
 184     case GL_STENCIL_PASS_DEPTH_FAIL:
 185       return 1;
 186     case GL_STENCIL_PASS_DEPTH_PASS:
 187       return 1;
 188     case GL_STENCIL_REF:
 189       return 1;
 190     case GL_STENCIL_TEST:
 191       return 1;
 192     case GL_STENCIL_VALUE_MASK:
 193       return 1;
 194     case GL_STENCIL_WRITEMASK:
 195       return 1;
 196     case GL_SUBPIXEL_BITS:
 197       return 1;
 198     case GL_TEXTURE_BINDING_2D:
 199       return 1;
 200     case GL_TEXTURE_BINDING_CUBE_MAP:
 201       return 1;
 202     case GL_TEXTURE_BINDING_EXTERNAL_OES:
 203       return 1;
 204     case GL_TEXTURE_BINDING_RECTANGLE_ARB:
 205       return 1;
 206     case GL_UNPACK_ALIGNMENT:
 207       return 1;
 208     case GL_VIEWPORT:
 209       return 4;
 210
 211     // ES3
 212     case GL_COPY_READ_BUFFER_BINDING:
 213       return 1;
 214     case GL_COPY_WRITE_BUFFER_BINDING:
 215       return 1;
 216     case GL_PIXEL_PACK_BUFFER_BINDING:
 217       return 1;
 218     case GL_PIXEL_UNPACK_BUFFER_BINDING:
 219       return 1;
 220     case GL_TRANSFORM_FEEDBACK_BUFFER_BINDING:
 221       return 1;
 222     case GL_UNIFORM_BUFFER_BINDING:
 223       return 1;
 224
 225     // -- glGetBooleanv, glGetFloatv, glGetIntergerv with
 226     //    GL_CHROMIUM_framebuffer_multisample
 227     case GL_MAX_SAMPLES_EXT:
 228       return 1;
 229     case GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT:
 230       return 1;
 231
 232     // -- glGetBufferParameteriv
 233     case GL_BUFFER_SIZE:
 234       return 1;
 235     case GL_BUFFER_USAGE:
 236       return 1;
 237
 238     // ES3
 239     case GL_BUFFER_MAPPED:
 240       return 1;
 241     case GL_BUFFER_ACCESS_FLAGS:
 242       return 1;
 243     case GL_BUFFER_MAP_LENGTH:
 244       return 1;
 245     case GL_BUFFER_MAP_OFFSET:
 246       return 1;
 247
 248     // -- glGetFramebufferAttachmentParameteriv
 249     case GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE:
 250       return 1;
 251     case GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME:
 252       return 1;
 253     case GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL:
 254       return 1;
 255     case GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE:
 256       return 1;
 257     // -- glGetFramebufferAttachmentParameteriv with
 258     //    GL_EXT_multisampled_render_to_texture
 259     case GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_SAMPLES_EXT:
 260       return 1;
 261     // -- glGetFramebufferAttachmentParameteriv with
 262     //    GL_EXT_sRGB
 263     case GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING_EXT:
 264       return 1;
 265     // ES3
 266     case GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE:
 267       return 1;
 268     case GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE:
 269       return 1;
 270     case GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE:
 271       return 1;
 272     case GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE:
 273       return 1;
 274     case GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE:
 275       return 1;
 276     case GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE:
 277       return 1;
 278     case GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE:
 279       return 1;
 280     case GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER:
 281       return 1;
 282
 283     // -- glGetProgramiv
 284     case GL_DELETE_STATUS:
 285       return 1;
 286     case GL_LINK_STATUS:
 287       return 1;
 288     case GL_VALIDATE_STATUS:
 289       return 1;
 290     case GL_INFO_LOG_LENGTH:
 291       return 1;
 292     case GL_ATTACHED_SHADERS:
 293       return 1;
 294     case GL_ACTIVE_ATTRIBUTES:
 295       return 1;
 296     case GL_ACTIVE_ATTRIBUTE_MAX_LENGTH:
 297       return 1;
 298     case GL_ACTIVE_UNIFORMS:
 299       return 1;
 300     case GL_ACTIVE_UNIFORM_MAX_LENGTH:
 301       return 1;
 302
 303     // -- glGetRenderbufferAttachmentParameteriv
 304     case GL_RENDERBUFFER_WIDTH:
 305       return 1;
 306     case GL_RENDERBUFFER_HEIGHT:
 307       return 1;
 308     case GL_RENDERBUFFER_INTERNAL_FORMAT:
 309       return 1;
 310     case GL_RENDERBUFFER_RED_SIZE:
 311       return 1;
 312     case GL_RENDERBUFFER_GREEN_SIZE:
 313       return 1;
 314     case GL_RENDERBUFFER_BLUE_SIZE:
 315       return 1;
 316     case GL_RENDERBUFFER_ALPHA_SIZE:
 317       return 1;
 318     case GL_RENDERBUFFER_DEPTH_SIZE:
 319       return 1;
 320     case GL_RENDERBUFFER_STENCIL_SIZE:
 321       return 1;
 322     // -- glGetRenderbufferAttachmentParameteriv with
 323     //    GL_EXT_multisampled_render_to_texture
 324     case GL_RENDERBUFFER_SAMPLES_EXT:
 325       return 1;
 326
 327     // -- glGetShaderiv
 328     case GL_SHADER_TYPE:
 329       return 1;
 330     // Already defined under glGetFramebufferAttachemntParameteriv.
 331     // case GL_DELETE_STATUS:
 332     //   return 1;
 333     case GL_COMPILE_STATUS:
 334       return 1;
 335     // Already defined under glGetFramebufferAttachemntParameteriv.
 336     // case GL_INFO_LOG_LENGTH:
 337     //   return 1;
 338     case GL_SHADER_SOURCE_LENGTH:
 339       return 1;
 340     case GL_TRANSLATED_SHADER_SOURCE_LENGTH_ANGLE:
 341       return 1;
 342
 343     // -- glGetTexParameterfv, glGetTexParameteriv
 344     case GL_TEXTURE_MAG_FILTER:
 345       return 1;
 346     case GL_TEXTURE_MIN_FILTER:
 347       return 1;
 348     case GL_TEXTURE_WRAP_R:
 349       return 1;
 350     case GL_TEXTURE_WRAP_S:
 351       return 1;
 352     case GL_TEXTURE_WRAP_T:
 353       return 1;
 354     case GL_TEXTURE_COMPARE_FUNC:
 355       return 1;
 356     case GL_TEXTURE_COMPARE_MODE:
 357       return 1;
 358     case GL_TEXTURE_MAX_LOD:
 359       return 1;
 360     case GL_TEXTURE_MIN_LOD:
 361       return 1;
 362     case GL_TEXTURE_BASE_LEVEL:
 363       return 1;
 364     case GL_TEXTURE_MAX_LEVEL:
 365       return 1;
 366     case GL_TEXTURE_IMMUTABLE_FORMAT:
 367       return 1;
 368     case GL_TEXTURE_IMMUTABLE_LEVELS:
 369       return 1;
 370     case GL_TEXTURE_MAX_ANISOTROPY_EXT:
 371       return 1;
 372
 373     // -- glGetVertexAttrib
 374     case GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING:
 375       return 1;
 376     case GL_VERTEX_ATTRIB_ARRAY_ENABLED:
 377       return 1;
 378     case GL_VERTEX_ATTRIB_ARRAY_SIZE:
 379       return 1;
 380     case GL_VERTEX_ATTRIB_ARRAY_STRIDE:
 381       return 1;
 382     case GL_VERTEX_ATTRIB_ARRAY_TYPE:
 383       return 1;
 384     case GL_VERTEX_ATTRIB_ARRAY_NORMALIZED:
 385       return 1;
 386     case GL_CURRENT_VERTEX_ATTRIB:
 387       return 4;
 388     case GL_VERTEX_ATTRIB_ARRAY_INTEGER:
 389       return 1;
 390     case GL_VERTEX_ATTRIB_ARRAY_DIVISOR:
 391       return 1;
 392
 393     // -- glGetSynciv
 394     case GL_OBJECT_TYPE:
 395       return 1;
 396     case GL_SYNC_STATUS:
 397       return 1;
 398     case GL_SYNC_CONDITION:
 399       return 1;
 400     case GL_SYNC_FLAGS:
 401       return 1;
 402
 403     // -- glHint with GL_OES_standard_derivatives
 404     case GL_FRAGMENT_SHADER_DERIVATIVE_HINT_OES:
 405       return 1;
 406
 407     // Chromium internal bind_generates_resource query
 408     case GL_BIND_GENERATES_RESOURCE_CHROMIUM:
 409       return 1;
 410
 411     // bad enum
 412     default:
 413       return 0;
 414   }
 415 }
 416
 417 namespace {
 418
 419 // Return the number of elements per group of a specified format.
 420 int ElementsPerGroup(int format, int type) {
 421   switch (type) {
 422     case GL_UNSIGNED_SHORT_5_6_5:
 423     case GL_UNSIGNED_SHORT_4_4_4_4:
 424     case GL_UNSIGNED_SHORT_5_5_5_1:
 425     case GL_UNSIGNED_INT_24_8_OES:
 426     case GL_UNSIGNED_INT_2_10_10_10_REV:
 427     case GL_UNSIGNED_INT_10F_11F_11F_REV:
 428     case GL_UNSIGNED_INT_5_9_9_9_REV:
 429     case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
 430        return 1;
 431     default:
 432        break;
 433     }
 434
 435     switch (format) {
 436     case GL_RGB:
 437     case GL_RGB_INTEGER:
 438     case GL_SRGB_EXT:
 439        return 3;
 440     case GL_LUMINANCE_ALPHA:
 441     case GL_RG_EXT:
 442     case GL_RG_INTEGER:
 443        return 2;
 444     case GL_RGBA:
 445     case GL_RGBA_INTEGER:
 446     case GL_BGRA_EXT:
 447     case GL_SRGB_ALPHA_EXT:
 448        return 4;
 449     case GL_ALPHA:
 450     case GL_LUMINANCE:
 451     case GL_DEPTH_COMPONENT:
 452     case GL_DEPTH_COMPONENT24_OES:
 453     case GL_DEPTH_COMPONENT32_OES:
 454     case GL_DEPTH_COMPONENT16:
 455     case GL_DEPTH24_STENCIL8_OES:
 456     case GL_DEPTH_STENCIL_OES:
 457     case GL_RED_EXT:
 458     case GL_RED_INTEGER:
 459        return 1;
 460     default:
 461        return 0;
 462   }
 463 }
 464
 465 // Return the number of bytes per element, based on the element type.
 466 int BytesPerElement(int type) {
 467   switch (type) {
 468     case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
 469       return 8;
 470     case GL_FLOAT:
 471     case GL_UNSIGNED_INT_24_8_OES:
 472     case GL_UNSIGNED_INT:
 473     case GL_INT:
 474     case GL_UNSIGNED_INT_2_10_10_10_REV:
 475     case GL_UNSIGNED_INT_10F_11F_11F_REV:
 476     case GL_UNSIGNED_INT_5_9_9_9_REV:
 477       return 4;
 478     case GL_HALF_FLOAT:
 479     case GL_HALF_FLOAT_OES:
 480     case GL_UNSIGNED_SHORT:
 481     case GL_SHORT:
 482     case GL_UNSIGNED_SHORT_5_6_5:
 483     case GL_UNSIGNED_SHORT_4_4_4_4:
 484     case GL_UNSIGNED_SHORT_5_5_5_1:
 485        return 2;
 486     case GL_UNSIGNED_BYTE:
 487     case GL_BYTE:
 488        return 1;
 489     default:
 490        return 0;
 491   }
 492 }
 493
 494 }  // anonymous namespace
 495
 496 uint32 GLES2Util::ComputeImageGroupSize(int format, int type) {
 497   int bytes_per_element = BytesPerElement(type);
 498   DCHECK_GE(8, bytes_per_element);
 499   int elements_per_group = ElementsPerGroup(format, type);
 500   DCHECK_GE(4, elements_per_group);
 501   return  bytes_per_element * elements_per_group;
 502 }
 503
 504 bool GLES2Util::ComputeImagePaddedRowSize(
 505         int width, int format, int type, int unpack_alignment,
 506         uint32* padded_row_size) {
 507   DCHECK(unpack_alignment == 1 || unpack_alignment == 2 ||
 508          unpack_alignment == 4 || unpack_alignment == 8);
 509   uint32 bytes_per_group = ComputeImageGroupSize(format, type);
 510   uint32 unpadded_row_size;
 511   if (!SafeMultiplyUint32(width, bytes_per_group, &unpadded_row_size)) {
 512     return false;
 513   }
 514   uint32 temp;
 515   if (!SafeAddUint32(unpadded_row_size, unpack_alignment - 1, &temp)) {
 516       return false;
 517   }
 518   *padded_row_size = (temp / unpack_alignment) * unpack_alignment;
 519   return true;
 520 }
 521
 522 // Returns the amount of data glTexImage*D or glTexSubImage*D will access.
 523 bool GLES2Util::ComputeImageDataSizes(
 524     int width, int height, int depth, int format, int type,
 525     int unpack_alignment, uint32* size, uint32* ret_unpadded_row_size,
 526     uint32* ret_padded_row_size) {
 527   DCHECK(unpack_alignment == 1 || unpack_alignment == 2 ||
 528          unpack_alignment == 4 || unpack_alignment == 8);
 529   uint32 bytes_per_group = ComputeImageGroupSize(format, type);
 530   uint32 row_size;
 531   if (!SafeMultiplyUint32(width, bytes_per_group, &row_size)) {
 532     return false;
 533   }
 534   uint32 num_of_rows;
 535   if (!SafeMultiplyUint32(height, depth, &num_of_rows)) {
 536     return false;
 537   }
 538   if (num_of_rows > 1) {
 539     uint32 temp;
 540     if (!SafeAddUint32(row_size, unpack_alignment - 1, &temp)) {
 541       return false;
 542     }
 543     uint32 padded_row_size = (temp / unpack_alignment) * unpack_alignment;
 544     uint32 size_of_all_but_last_row;
 545     if (!SafeMultiplyUint32((num_of_rows - 1), padded_row_size,
 546                             &size_of_all_but_last_row)) {
 547       return false;
 548     }
 549     if (!SafeAddUint32(size_of_all_but_last_row, row_size, size)) {
 550       return false;
 551     }
 552     if (ret_padded_row_size) {
 553       *ret_padded_row_size = padded_row_size;
 554     }
 555   } else {
 556     *size = row_size;
 557     if (ret_padded_row_size) {
 558       *ret_padded_row_size = row_size;
 559     }
 560   }
 561   if (ret_unpadded_row_size) {
 562     *ret_unpadded_row_size = row_size;
 563   }
 564
 565   return true;
 566 }
 567
 568 size_t GLES2Util::RenderbufferBytesPerPixel(int format) {
 569   switch (format) {
 570     case GL_STENCIL_INDEX8:
 571       return 1;
 572     case GL_RGBA4:
 573     case GL_RGB565:
 574     case GL_RGB5_A1:
 575     case GL_DEPTH_COMPONENT16:
 576       return 2;
 577     case GL_RGB:
 578     case GL_RGBA:
 579     case GL_DEPTH24_STENCIL8_OES:
 580     case GL_RGB8_OES:
 581     case GL_RGBA8_OES:
 582     case GL_DEPTH_COMPONENT24_OES:
 583       return 4;
 584     default:
 585       return 0;
 586   }
 587 }
 588
 589 uint32 GLES2Util::GetElementSizeForUniformType(int type) {
 590   switch (type) {
 591     case GL_FLOAT:
 592     case GL_FLOAT_VEC2:
 593     case GL_FLOAT_VEC3:
 594     case GL_FLOAT_VEC4:
 595     case GL_FLOAT_MAT2:
 596     case GL_FLOAT_MAT3:
 597     case GL_FLOAT_MAT4:
 598       return sizeof(GLfloat);
 599     case GL_INT:
 600     case GL_INT_VEC2:
 601     case GL_INT_VEC3:
 602     case GL_INT_VEC4:
 603     case GL_BOOL:
 604     case GL_BOOL_VEC2:
 605     case GL_BOOL_VEC3:
 606     case GL_BOOL_VEC4:
 607     case GL_SAMPLER_2D:
 608     case GL_SAMPLER_CUBE:
 609     case GL_SAMPLER_2D_RECT_ARB:  // extension.
 610     case GL_SAMPLER_EXTERNAL_OES:  // extension.
 611       return sizeof(GLint);
 612
 613     // ES3 types.
 614     case GL_UNSIGNED_INT:
 615     case GL_UNSIGNED_INT_VEC2:
 616     case GL_UNSIGNED_INT_VEC3:
 617     case GL_UNSIGNED_INT_VEC4:
 618       return sizeof(GLuint);
 619     case GL_SAMPLER_3D:
 620     case GL_SAMPLER_2D_SHADOW:
 621     case GL_SAMPLER_2D_ARRAY:
 622     case GL_SAMPLER_2D_ARRAY_SHADOW:
 623     case GL_SAMPLER_CUBE_SHADOW:
 624     case GL_INT_SAMPLER_2D:
 625     case GL_INT_SAMPLER_3D:
 626     case GL_INT_SAMPLER_CUBE:
 627     case GL_INT_SAMPLER_2D_ARRAY:
 628     case GL_UNSIGNED_INT_SAMPLER_2D:
 629     case GL_UNSIGNED_INT_SAMPLER_3D:
 630     case GL_UNSIGNED_INT_SAMPLER_CUBE:
 631     case GL_UNSIGNED_INT_SAMPLER_2D_ARRAY:
 632       return sizeof(GLint);
 633     case GL_FLOAT_MAT2x3:
 634     case GL_FLOAT_MAT3x2:
 635     case GL_FLOAT_MAT2x4:
 636     case GL_FLOAT_MAT4x2:
 637     case GL_FLOAT_MAT3x4:
 638     case GL_FLOAT_MAT4x3:
 639       return sizeof(GLfloat);
 640
 641     default:
 642       return 0;
 643   }
 644 }
 645
 646 uint32 GLES2Util::GetElementCountForUniformType(int type) {
 647   switch (type) {
 648     case GL_FLOAT:
 649     case GL_INT:
 650     case GL_BOOL:
 651     case GL_SAMPLER_2D:
 652     case GL_SAMPLER_CUBE:
 653     case GL_SAMPLER_2D_RECT_ARB:  // extension.
 654     case GL_SAMPLER_EXTERNAL_OES:  // extension.
 655       return 1;
 656     case GL_FLOAT_VEC2:
 657     case GL_INT_VEC2:
 658     case GL_BOOL_VEC2:
 659       return 2;
 660     case GL_FLOAT_VEC3:
 661     case GL_INT_VEC3:
 662     case GL_BOOL_VEC3:
 663       return 3;
 664     case GL_FLOAT_VEC4:
 665     case GL_INT_VEC4:
 666     case GL_BOOL_VEC4:
 667     case GL_FLOAT_MAT2:
 668       return 4;
 669     case GL_FLOAT_MAT3:
 670       return 9;
 671     case GL_FLOAT_MAT4:
 672       return 16;
 673
 674     // ES3 types.
 675     case GL_UNSIGNED_INT:
 676     case GL_SAMPLER_3D:
 677     case GL_SAMPLER_2D_SHADOW:
 678     case GL_SAMPLER_2D_ARRAY:
 679     case GL_SAMPLER_2D_ARRAY_SHADOW:
 680     case GL_SAMPLER_CUBE_SHADOW:
 681     case GL_INT_SAMPLER_2D:
 682     case GL_INT_SAMPLER_3D:
 683     case GL_INT_SAMPLER_CUBE:
 684     case GL_INT_SAMPLER_2D_ARRAY:
 685     case GL_UNSIGNED_INT_SAMPLER_2D:
 686     case GL_UNSIGNED_INT_SAMPLER_3D:
 687     case GL_UNSIGNED_INT_SAMPLER_CUBE:
 688     case GL_UNSIGNED_INT_SAMPLER_2D_ARRAY:
 689       return 1;
 690     case GL_UNSIGNED_INT_VEC2:
 691       return 2;
 692     case GL_UNSIGNED_INT_VEC3:
 693       return 3;
 694     case GL_UNSIGNED_INT_VEC4:
 695       return 4;
 696     case GL_FLOAT_MAT2x3:
 697     case GL_FLOAT_MAT3x2:
 698       return 6;
 699     case GL_FLOAT_MAT2x4:
 700     case GL_FLOAT_MAT4x2:
 701       return 8;
 702     case GL_FLOAT_MAT3x4:
 703     case GL_FLOAT_MAT4x3:
 704       return 12;
 705
 706     default:
 707       return 0;
 708   }
 709 }
 710
 711 size_t GLES2Util::GetGLTypeSizeForTexturesAndBuffers(uint32 type) {
 712   switch (type) {
 713     case GL_BYTE:
 714       return sizeof(GLbyte);  // NOLINT
 715     case GL_UNSIGNED_BYTE:
 716       return sizeof(GLubyte);  // NOLINT
 717     case GL_SHORT:
 718       return sizeof(GLshort);  // NOLINT
 719     case GL_UNSIGNED_SHORT:
 720       return sizeof(GLushort);  // NOLINT
 721     case GL_INT:
 722       return sizeof(GLint);  // NOLINT
 723     case GL_UNSIGNED_INT:
 724       return sizeof(GLuint);  // NOLINT
 725     case GL_FLOAT:
 726       return sizeof(GLfloat);  // NOLINT
 727     case GL_FIXED:
 728       return sizeof(GLfixed);  // NOLINT
 729     default:
 730       return 0;
 731   }
 732 }
 733
 734 size_t GLES2Util::GetGLTypeSizeForPathCoordType(uint32 type) {
 735   switch (type) {
 736     case GL_BYTE:
 737       return sizeof(GLbyte);  // NOLINT
 738     case GL_UNSIGNED_BYTE:
 739       return sizeof(GLubyte);  // NOLINT
 740     case GL_SHORT:
 741       return sizeof(GLshort);  // NOLINT
 742     case GL_UNSIGNED_SHORT:
 743       return sizeof(GLushort);  // NOLINT
 744     case GL_FLOAT:
 745       return sizeof(GLfloat);  // NOLINT
 746     default:
 747       return 0;
 748   }
 749 }
 750
 751 uint32 GLES2Util::GLErrorToErrorBit(uint32 error) {
 752   switch (error) {
 753     case GL_INVALID_ENUM:
 754       return gl_error_bit::kInvalidEnum;
 755     case GL_INVALID_VALUE:
 756       return gl_error_bit::kInvalidValue;
 757     case GL_INVALID_OPERATION:
 758       return gl_error_bit::kInvalidOperation;
 759     case GL_OUT_OF_MEMORY:
 760       return gl_error_bit::kOutOfMemory;
 761     case GL_INVALID_FRAMEBUFFER_OPERATION:
 762       return gl_error_bit::kInvalidFrameBufferOperation;
 763     case GL_CONTEXT_LOST_KHR:
 764       return gl_error_bit::kContextLost;
 765     default:
 766       NOTREACHED();
 767       return gl_error_bit::kNoError;
 768   }
 769 }
 770
 771 uint32 GLES2Util::GLErrorBitToGLError(uint32 error_bit) {
 772   switch (error_bit) {
 773     case gl_error_bit::kInvalidEnum:
 774       return GL_INVALID_ENUM;
 775     case gl_error_bit::kInvalidValue:
 776       return GL_INVALID_VALUE;
 777     case gl_error_bit::kInvalidOperation:
 778       return GL_INVALID_OPERATION;
 779     case gl_error_bit::kOutOfMemory:
 780       return GL_OUT_OF_MEMORY;
 781     case gl_error_bit::kInvalidFrameBufferOperation:
 782       return GL_INVALID_FRAMEBUFFER_OPERATION;
 783     case gl_error_bit::kContextLost:
 784       return GL_CONTEXT_LOST_KHR;
 785     default:
 786       NOTREACHED();
 787       return GL_NO_ERROR;
 788   }
 789 }
 790
 791 uint32 GLES2Util::IndexToGLFaceTarget(int index) {
 792   static uint32 faces[] = {
 793     GL_TEXTURE_CUBE_MAP_POSITIVE_X,
 794     GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
 795     GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
 796     GL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
 797     GL_TEXTURE_CUBE_MAP_POSITIVE_Z,
 798     GL_TEXTURE_CUBE_MAP_NEGATIVE_Z,
 799   };
 800   return faces[index];
 801 }
 802
 803 size_t GLES2Util::GLTargetToFaceIndex(uint32 target) {
 804   switch (target) {
 805     case GL_TEXTURE_2D:
 806     case GL_TEXTURE_EXTERNAL_OES:
 807     case GL_TEXTURE_RECTANGLE_ARB:
 808     case GL_TEXTURE_3D:
 809     case GL_TEXTURE_2D_ARRAY:
 810       return 0;
 811     case GL_TEXTURE_CUBE_MAP_POSITIVE_X:
 812       return 0;
 813     case GL_TEXTURE_CUBE_MAP_NEGATIVE_X:
 814       return 1;
 815     case GL_TEXTURE_CUBE_MAP_POSITIVE_Y:
 816       return 2;
 817     case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y:
 818       return 3;
 819     case GL_TEXTURE_CUBE_MAP_POSITIVE_Z:
 820       return 4;
 821     case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z:
 822       return 5;
 823     default:
 824       NOTREACHED();
 825       return 0;
 826   }
 827 }
 828
 829 uint32 GLES2Util::GetGLReadPixelsImplementationFormat(
 830     uint32 internal_format) {
 831   switch (internal_format) {
 832     case GL_R8:
 833     case GL_R16F:
 834     case GL_R32F:
 835       return GL_RED;
 836     case GL_R8UI:
 837     case GL_R8I:
 838     case GL_R16UI:
 839     case GL_R16I:
 840     case GL_R32UI:
 841     case GL_R32I:
 842       return GL_RED_INTEGER;
 843     case GL_RG8:
 844     case GL_RG16F:
 845     case GL_RG32F:
 846       return GL_RG;
 847     case GL_RG8UI:
 848     case GL_RG8I:
 849     case GL_RG16UI:
 850     case GL_RG16I:
 851     case GL_RG32UI:
 852     case GL_RG32I:
 853       return GL_RG_INTEGER;
 854     case GL_RGB:
 855     case GL_RGB8:
 856     case GL_RGB565:
 857     case GL_R11F_G11F_B10F:
 858     case GL_RGB16F:
 859     case GL_RGB32F:
 860       return GL_RGB;
 861     case GL_RGBA8UI:
 862     case GL_RGBA8I:
 863     case GL_RGB10_A2UI:
 864     case GL_RGBA16UI:
 865     case GL_RGBA16I:
 866     case GL_RGBA32UI:
 867     case GL_RGBA32I:
 868       return GL_RGBA_INTEGER;
 869     default:
 870       return GL_RGBA;
 871   }
 872 }
 873
 874 uint32 GLES2Util::GetGLReadPixelsImplementationType(
 875     uint32 internal_format, uint32 texture_type) {
 876   switch (internal_format) {
 877     case GL_R16UI:
 878     case GL_RG16UI:
 879     case GL_RGBA16UI:
 880     case GL_RGB10_A2:
 881     case GL_RGB10_A2UI:
 882       return GL_UNSIGNED_SHORT;
 883     case GL_R32UI:
 884     case GL_RG32UI:
 885     case GL_RGBA32UI:
 886       return GL_UNSIGNED_INT;
 887     case GL_R8I:
 888     case GL_RG8I:
 889     case GL_RGBA8I:
 890       return GL_BYTE;
 891     case GL_R16I:
 892     case GL_RG16I:
 893     case GL_RGBA16I:
 894       return GL_SHORT;
 895     case GL_R32I:
 896     case GL_RG32I:
 897     case GL_RGBA32I:
 898       return GL_INT;
 899     case GL_R32F:
 900     case GL_RG32F:
 901     case GL_RGB32F:
 902     case GL_RGBA32F:
 903       return GL_FLOAT;
 904     case GL_R16F:
 905     case GL_RG16F:
 906     case GL_R11F_G11F_B10F:
 907     case GL_RGB16F:
 908     case GL_RGBA16F:
 909       // TODO(zmo): Consider return GL_UNSIGNED_INT_10F_11F_11F_REV and
 910       // GL_HALF_FLOAT.
 911       return GL_FLOAT;
 912     case GL_RGBA:
 913     case GL_RGB:
 914       // Unsized internal format, check the type
 915       switch (texture_type) {
 916         case GL_FLOAT:
 917         case GL_HALF_FLOAT_OES:
 918           return GL_FLOAT;
 919         // TODO(zmo): Consider return GL_UNSIGNED_SHORT_5_6_5,
 920         // GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_5_5_5_1, and
 921         // GL_UNSIGNED_INT_2_10_10_10_REV.
 922         default:
 923           return GL_UNSIGNED_BYTE;
 924       }
 925     default:
 926       return GL_UNSIGNED_BYTE;
 927   }
 928 }
 929
 930 uint32 GLES2Util::GetChannelsForFormat(int format) {
 931   switch (format) {
 932     case GL_ALPHA:
 933     case GL_ALPHA16F_EXT:
 934     case GL_ALPHA32F_EXT:
 935       return kAlpha;
 936     case GL_LUMINANCE:
 937       return kRGB;
 938     case GL_LUMINANCE_ALPHA:
 939       return kRGBA;
 940     case GL_RGB:
 941     case GL_RGB8_OES:
 942     case GL_RGB565:
 943     case GL_RGB16F_EXT:
 944     case GL_RGB32F_EXT:
 945     case GL_SRGB_EXT:
 946     case GL_SRGB8:
 947     case GL_RGB8_SNORM:
 948     case GL_R11F_G11F_B10F:
 949     case GL_RGB9_E5:
 950     case GL_RGB8UI:
 951     case GL_RGB8I:
 952     case GL_RGB16UI:
 953     case GL_RGB16I:
 954     case GL_RGB32UI:
 955     case GL_RGB32I:
 956       return kRGB;
 957     case GL_BGRA_EXT:
 958     case GL_BGRA8_EXT:
 959     case GL_RGBA16F_EXT:
 960     case GL_RGBA32F_EXT:
 961     case GL_RGBA:
 962     case GL_RGBA8_OES:
 963     case GL_RGBA4:
 964     case GL_RGB5_A1:
 965     case GL_SRGB_ALPHA_EXT:
 966     case GL_SRGB8_ALPHA8_EXT:
 967     case GL_RGBA8_SNORM:
 968     case GL_RGB10_A2:
 969     case GL_RGBA8UI:
 970     case GL_RGBA8I:
 971     case GL_RGB10_A2UI:
 972     case GL_RGBA16UI:
 973     case GL_RGBA16I:
 974     case GL_RGBA32UI:
 975     case GL_RGBA32I:
 976       return kRGBA;
 977     case GL_DEPTH_COMPONENT32_OES:
 978     case GL_DEPTH_COMPONENT24_OES:
 979     case GL_DEPTH_COMPONENT16:
 980     case GL_DEPTH_COMPONENT:
 981     case GL_DEPTH_COMPONENT32F:
 982       return kDepth;
 983     case GL_STENCIL_INDEX8:
 984       return kStencil;
 985     case GL_DEPTH_STENCIL_OES:
 986     case GL_DEPTH24_STENCIL8_OES:
 987     case GL_DEPTH32F_STENCIL8:
 988       return kDepth | kStencil;
 989     case GL_RED_EXT:
 990     case GL_R8:
 991     case GL_R8_SNORM:
 992     case GL_R16F:
 993     case GL_R32F:
 994     case GL_R8UI:
 995     case GL_R8I:
 996     case GL_R16UI:
 997     case GL_R16I:
 998     case GL_R32UI:
 999     case GL_R32I:
1000       return kRed;
1001     case GL_RG_EXT:
1002     case GL_RG8:
1003     case GL_RG8_SNORM:
1004     case GL_RG16F:
1005     case GL_RG32F:
1006     case GL_RG8UI:
1007     case GL_RG8I:
1008     case GL_RG16UI:
1009     case GL_RG16I:
1010     case GL_RG32UI:
1011     case GL_RG32I:
1012       return kRed | kGreen;
1013     default:
1014       return 0x0000;
1015   }
1016 }
1017
1018 uint32 GLES2Util::GetChannelsNeededForAttachmentType(
1019     int type, uint32 max_color_attachments) {
1020   switch (type) {
1021     case GL_DEPTH_ATTACHMENT:
1022       return kDepth;
1023     case GL_STENCIL_ATTACHMENT:
1024       return kStencil;
1025     default:
1026       if (type >= GL_COLOR_ATTACHMENT0 &&
1027           type < static_cast<int>(
1028               GL_COLOR_ATTACHMENT0 + max_color_attachments)) {
1029         return kRGBA;
1030       }
1031       return 0x0000;
1032   }
1033 }
1034
1035 std::string GLES2Util::GetStringEnum(uint32 value) {
1036   const EnumToString* entry = enum_to_string_table_;
1037   const EnumToString* end = entry + enum_to_string_table_len_;
1038   for (;entry < end; ++entry) {
1039     if (value == entry->value) {
1040       return entry->name;
1041     }
1042   }
1043   std::stringstream ss;
1044   ss.fill('0');
1045   ss.width(value < 0x10000 ? 4 : 8);
1046   ss << std::hex << value;
1047   return "0x" + ss.str();
1048 }
1049
1050 std::string GLES2Util::GetStringError(uint32 value) {
1051   static EnumToString string_table[] = {
1052     { GL_NONE, "GL_NONE" },
1053   };
1054   return GLES2Util::GetQualifiedEnumString(
1055       string_table, arraysize(string_table), value);
1056 }
1057
1058 std::string GLES2Util::GetStringBool(uint32 value) {
1059   return value ? "GL_TRUE" : "GL_FALSE";
1060 }
1061
1062 std::string GLES2Util::GetQualifiedEnumString(
1063     const EnumToString* table, size_t count, uint32 value) {
1064   for (const EnumToString* end = table + count; table < end; ++table) {
1065     if (table->value == value) {
1066       return table->name;
1067     }
1068   }
1069   return GetStringEnum(value);
1070 }
1071
1072 bool GLES2Util::ParseUniformName(
1073     const std::string& name,
1074     size_t* array_pos,
1075     int* element_index,
1076     bool* getting_array) {
1077   if (name.empty())
1078     return false;
1079   bool getting_array_location = false;
1080   size_t open_pos = std::string::npos;
1081   base::CheckedNumeric<int> index = 0;
1082   if (name[name.size() - 1] == ']') {
1083     if (name.size() < 3) {
1084       return false;
1085     }
1086     open_pos = name.find_last_of('[');
1087     if (open_pos == std::string::npos ||
1088         open_pos >= name.size() - 2) {
1089       return false;
1090     }
1091     size_t last = name.size() - 1;
1092     for (size_t pos = open_pos + 1; pos < last; ++pos) {
1093       int8 digit = name[pos] - '0';
1094       if (digit < 0 || digit > 9) {
1095         return false;
1096       }
1097       index = index * 10 + digit;
1098     }
1099     if (!index.IsValid()) {
1100       return false;
1101     }
1102     getting_array_location = true;
1103   }
1104   *getting_array = getting_array_location;
1105   *element_index = index.ValueOrDie();
1106   *array_pos = open_pos;
1107   return true;
1108 }
1109
1110 size_t GLES2Util::CalcClearBufferivDataCount(int buffer) {
1111   switch (buffer) {
1112     case GL_COLOR:
1113       return 4;
1114     case GL_STENCIL:
1115       return 1;
1116     default:
1117       return 0;
1118   }
1119 }
1120
1121 size_t GLES2Util::CalcClearBufferfvDataCount(int buffer) {
1122   switch (buffer) {
1123     case GL_COLOR:
1124       return 4;
1125     case GL_DEPTH:
1126       return 1;
1127     default:
1128       return 0;
1129   }
1130 }
1131
1132 // static
1133 void GLES2Util::MapUint64ToTwoUint32(
1134     uint64_t v64, uint32_t* v32_0, uint32_t* v32_1) {
1135   DCHECK(v32_0 && v32_1);
1136   *v32_0 = static_cast<uint32_t>(v64 & 0xFFFFFFFF);
1137   *v32_1 = static_cast<uint32_t>((v64 & 0xFFFFFFFF00000000) >> 32);
1138 }
1139
1140 // static
1141 uint64_t GLES2Util::MapTwoUint32ToUint64(uint32_t v32_0, uint32_t v32_1) {
1142   uint64_t v64 = v32_1;
1143   return (v64 << 32) | v32_0;
1144 }
1145
1146 // static
1147 uint32_t GLES2Util::MapBufferTargetToBindingEnum(uint32_t target) {
1148   switch (target) {
1149     case GL_ARRAY_BUFFER:
1150       return GL_ARRAY_BUFFER_BINDING;
1151     case GL_COPY_READ_BUFFER:
1152       return GL_COPY_READ_BUFFER_BINDING;
1153     case GL_COPY_WRITE_BUFFER:
1154       return GL_COPY_WRITE_BUFFER_BINDING;
1155     case GL_ELEMENT_ARRAY_BUFFER:
1156       return GL_ELEMENT_ARRAY_BUFFER_BINDING;
1157     case GL_PIXEL_PACK_BUFFER:
1158       return GL_PIXEL_PACK_BUFFER_BINDING;
1159     case GL_PIXEL_UNPACK_BUFFER:
1160       return GL_PIXEL_UNPACK_BUFFER_BINDING;
1161     case GL_TRANSFORM_FEEDBACK_BUFFER:
1162       return GL_TRANSFORM_FEEDBACK_BUFFER_BINDING;
1163     case GL_UNIFORM_BUFFER:
1164       return GL_UNIFORM_BUFFER_BINDING;
1165     default:
1166       return 0;
1167   }
1168 }
1169
1170 // static
1171 bool GLES2Util::IsUnsignedIntegerFormat(uint32_t internal_format) {
1172   switch (internal_format) {
1173     case GL_R8UI:
1174     case GL_R16UI:
1175     case GL_R32UI:
1176     case GL_RG8UI:
1177     case GL_RG16UI:
1178     case GL_RG32UI:
1179     case GL_RGBA8UI:
1180     case GL_RGB10_A2UI:
1181     case GL_RGBA16UI:
1182     case GL_RGBA32UI:
1183       return true;
1184     default:
1185       return false;
1186   }
1187 }
1188
1189 // static
1190 bool GLES2Util::IsSignedIntegerFormat(uint32_t internal_format) {
1191   switch (internal_format) {
1192     case GL_R8I:
1193     case GL_R16I:
1194     case GL_R32I:
1195     case GL_RG8I:
1196     case GL_RG16I:
1197     case GL_RG32I:
1198     case GL_RGBA8I:
1199     case GL_RGBA16I:
1200     case GL_RGBA32I:
1201       return true;
1202     default:
1203       return false;
1204   }
1205 }
1206
1207 // static
1208 bool GLES2Util::IsIntegerFormat(uint32_t internal_format) {
1209   return (IsUnsignedIntegerFormat(internal_format) ||
1210           IsSignedIntegerFormat(internal_format));
1211 }
1212
1213
1214 namespace {
1215
1216 // WebGraphicsContext3DCommandBufferImpl configuration attributes. Those in
1217 // the 16-bit range are the same as used by EGL. Those outside the 16-bit range
1218 // are unique to Chromium. Attributes are matched using a closest fit algorithm.
1219
1220 // From <EGL/egl.h>.
1221 const int32 kAlphaSize       = 0x3021;  // EGL_ALPHA_SIZE
1222 const int32 kBlueSize        = 0x3022;  // EGL_BLUE_SIZE
1223 const int32 kGreenSize       = 0x3023;  // EGL_GREEN_SIZE
1224 const int32 kRedSize         = 0x3024;  // EGL_RED_SIZE
1225 const int32 kDepthSize       = 0x3025;  // EGL_DEPTH_SIZE
1226 const int32 kStencilSize     = 0x3026;  // EGL_STENCIL_SIZE
1227 const int32 kSamples         = 0x3031;  // EGL_SAMPLES
1228 const int32 kSampleBuffers   = 0x3032;  // EGL_SAMPLE_BUFFERS
1229 const int32 kNone            = 0x3038;  // EGL_NONE
1230 const int32 kSwapBehavior    = 0x3093;  // EGL_SWAP_BEHAVIOR
1231 const int32 kBufferPreserved = 0x3094;  // EGL_BUFFER_PRESERVED
1232 const int32 kBufferDestroyed = 0x3095;  // EGL_BUFFER_DESTROYED
1233
1234 // Chromium only.
1235 const int32 kBindGeneratesResource = 0x10000;
1236 const int32 kFailIfMajorPerfCaveat = 0x10001;
1237 const int32 kLoseContextWhenOutOfMemory = 0x10002;
1238 const int32 kWebGLVersion = 0x10003;
1239
1240 }  // namespace
1241
1242 ContextCreationAttribHelper::ContextCreationAttribHelper()
1243     : alpha_size(-1),
1244       blue_size(-1),
1245       green_size(-1),
1246       red_size(-1),
1247       depth_size(-1),
1248       stencil_size(-1),
1249       samples(-1),
1250       sample_buffers(-1),
1251       buffer_preserved(true),
1252       bind_generates_resource(true),
1253       fail_if_major_perf_caveat(false),
1254       lose_context_when_out_of_memory(false),
1255       webgl_version(0) {
1256 }
1257
1258 void ContextCreationAttribHelper::Serialize(std::vector<int32>* attribs) const {
1259   if (alpha_size != -1) {
1260     attribs->push_back(kAlphaSize);
1261     attribs->push_back(alpha_size);
1262   }
1263   if (blue_size != -1) {
1264     attribs->push_back(kBlueSize);
1265     attribs->push_back(blue_size);
1266   }
1267   if (green_size != -1) {
1268     attribs->push_back(kGreenSize);
1269     attribs->push_back(green_size);
1270   }
1271   if (red_size != -1) {
1272     attribs->push_back(kRedSize);
1273     attribs->push_back(red_size);
1274   }
1275   if (depth_size != -1) {
1276     attribs->push_back(kDepthSize);
1277     attribs->push_back(depth_size);
1278   }
1279   if (stencil_size != -1) {
1280     attribs->push_back(kStencilSize);
1281     attribs->push_back(stencil_size);
1282   }
1283   if (samples != -1) {
1284     attribs->push_back(kSamples);
1285     attribs->push_back(samples);
1286   }
1287   if (sample_buffers != -1) {
1288     attribs->push_back(kSampleBuffers);
1289     attribs->push_back(sample_buffers);
1290   }
1291   attribs->push_back(kSwapBehavior);
1292   attribs->push_back(buffer_preserved ? kBufferPreserved : kBufferDestroyed);
1293   attribs->push_back(kBindGeneratesResource);
1294   attribs->push_back(bind_generates_resource ? 1 : 0);
1295   attribs->push_back(kFailIfMajorPerfCaveat);
1296   attribs->push_back(fail_if_major_perf_caveat ? 1 : 0);
1297   attribs->push_back(kLoseContextWhenOutOfMemory);
1298   attribs->push_back(lose_context_when_out_of_memory ? 1 : 0);
1299   attribs->push_back(kWebGLVersion);
1300   attribs->push_back(webgl_version);
1301   attribs->push_back(kNone);
1302 }
1303
1304 bool ContextCreationAttribHelper::Parse(const std::vector<int32>& attribs) {
1305   for (size_t i = 0; i < attribs.size(); i += 2) {
1306     const int32 attrib = attribs[i];
1307     if (i + 1 >= attribs.size()) {
1308       if (attrib == kNone) {
1309         return true;
1310       }
1311
1312       DLOG(ERROR) << "Missing value after context creation attribute: "
1313                   << attrib;
1314       return false;
1315     }
1316
1317     const int32 value = attribs[i+1];
1318     switch (attrib) {
1319       case kAlphaSize:
1320         alpha_size = value;
1321         break;
1322       case kBlueSize:
1323         blue_size = value;
1324         break;
1325       case kGreenSize:
1326         green_size = value;
1327         break;
1328       case kRedSize:
1329         red_size = value;
1330         break;
1331       case kDepthSize:
1332         depth_size = value;
1333         break;
1334       case kStencilSize:
1335         stencil_size = value;
1336         break;
1337       case kSamples:
1338         samples = value;
1339         break;
1340       case kSampleBuffers:
1341         sample_buffers = value;
1342         break;
1343       case kSwapBehavior:
1344         buffer_preserved = value == kBufferPreserved;
1345         break;
1346       case kBindGeneratesResource:
1347         bind_generates_resource = value != 0;
1348         break;
1349       case kFailIfMajorPerfCaveat:
1350         fail_if_major_perf_caveat = value != 0;
1351         break;
1352       case kLoseContextWhenOutOfMemory:
1353         lose_context_when_out_of_memory = value != 0;
1354         break;
1355       case kWebGLVersion:
1356         webgl_version = value;
1357         break;
1358       case kNone:
1359         // Terminate list, even if more attributes.
1360         return true;
1361       default:
1362         DLOG(ERROR) << "Invalid context creation attribute: " << attrib;
1363         return false;
1364     }
1365   }
1366
1367   return true;
1368 }
1369
1370 #include "gpu/command_buffer/common/gles2_cmd_utils_implementation_autogen.h"
1371
1372 }  // namespace gles2
1373 }  // namespace gpu
1374