cc/resources/resource_format.cc

   1 // Copyright 2013 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 #include "cc/resources/resource_format.h"
   6
   7 #include "third_party/khronos/GLES2/gl2.h"
   8 #include "third_party/khronos/GLES2/gl2ext.h"
   9
  10 namespace cc {
  11
  12 SkColorType ResourceFormatToSkColorType(ResourceFormat format) {
  13   switch (format) {
  14     case RGBA_4444:
  15       return kARGB_4444_SkColorType;
  16     case RGBA_8888:
  17     case BGRA_8888:
  18       return kN32_SkColorType;
  19     case ETC1:
  20     case ALPHA_8:
  21     case LUMINANCE_8:
  22     case RGB_565:
  23     case RED_8:
  24       NOTREACHED();
  25       break;
  26   }
  27   NOTREACHED();
  28   return kN32_SkColorType;
  29 }
  30
  31 int BitsPerPixel(ResourceFormat format) {
  32   switch (format) {
  33     case BGRA_8888:
  34     case RGBA_8888:
  35       return 32;
  36     case RGBA_4444:
  37     case RGB_565:
  38       return 16;
  39     case ALPHA_8:
  40     case LUMINANCE_8:
  41     case RED_8:
  42       return 8;
  43     case ETC1:
  44       return 4;
  45   }
  46   NOTREACHED();
  47   return 0;
  48 }
  49
  50 GLenum GLDataType(ResourceFormat format) {
  51   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
  52   static const GLenum format_gl_data_type[] = {
  53       GL_UNSIGNED_BYTE,           // RGBA_8888
  54       GL_UNSIGNED_SHORT_4_4_4_4,  // RGBA_4444
  55       GL_UNSIGNED_BYTE,           // BGRA_8888
  56       GL_UNSIGNED_BYTE,           // ALPHA_8
  57       GL_UNSIGNED_BYTE,           // LUMINANCE_8
  58       GL_UNSIGNED_SHORT_5_6_5,    // RGB_565,
  59       GL_UNSIGNED_BYTE,           // ETC1
  60       GL_UNSIGNED_BYTE            // RED_8
  61   };
  62   static_assert(arraysize(format_gl_data_type) == (RESOURCE_FORMAT_MAX + 1),
  63                 "format_gl_data_type does not handle all cases.");
  64
  65   return format_gl_data_type[format];
  66 }
  67
  68 GLenum GLDataFormat(ResourceFormat format) {
  69   DCHECK_LE(format, RESOURCE_FORMAT_MAX);
  70   static const GLenum format_gl_data_format[] = {
  71       GL_RGBA,           // RGBA_8888
  72       GL_RGBA,           // RGBA_4444
  73       GL_BGRA_EXT,       // BGRA_8888
  74       GL_ALPHA,          // ALPHA_8
  75       GL_LUMINANCE,      // LUMINANCE_8
  76       GL_RGB,            // RGB_565
  77       GL_ETC1_RGB8_OES,  // ETC1
  78       GL_RED_EXT         // RED_8
  79   };
  80   static_assert(arraysize(format_gl_data_format) == (RESOURCE_FORMAT_MAX + 1),
  81                 "format_gl_data_format does not handle all cases.");
  82
  83   return format_gl_data_format[format];
  84 }
  85
  86 GLenum GLInternalFormat(ResourceFormat format) {
  87   return GLDataFormat(format);
  88 }
  89
  90 }  // namespace cc