cc/resources/platform_color.h

   1 // Copyright 2011 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 #ifndef CC_RESOURCES_PLATFORM_COLOR_H_
   6 #define CC_RESOURCES_PLATFORM_COLOR_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/logging.h"
  10 #include "cc/resources/resource_format.h"
  11 #include "third_party/skia/include/core/SkTypes.h"
  12
  13 namespace cc {
  14
  15 class PlatformColor {
  16  public:
  17   enum SourceDataFormat {
  18     SOURCE_FORMAT_RGBA8,
  19     SOURCE_FORMAT_BGRA8
  20   };
  21
  22   static SourceDataFormat Format() {
  23     return SK_B32_SHIFT ? SOURCE_FORMAT_RGBA8 : SOURCE_FORMAT_BGRA8;
  24   }
  25
  26   // Returns the most efficient texture format for this platform.
  27   static ResourceFormat BestTextureFormat(bool supports_bgra8888) {
  28     switch (Format()) {
  29       case SOURCE_FORMAT_BGRA8:
  30         return (supports_bgra8888) ? BGRA_8888 : RGBA_8888;
  31       case SOURCE_FORMAT_RGBA8:
  32         return RGBA_8888;
  33     }
  34     NOTREACHED();
  35     return RGBA_8888;
  36   }
  37
  38   // Return true if the given texture format has the same component order
  39   // as the color on this platform.
  40   static bool SameComponentOrder(ResourceFormat format) {
  41     switch (Format()) {
  42       case SOURCE_FORMAT_RGBA8:
  43         return format == RGBA_8888 || format == RGBA_4444;
  44       case SOURCE_FORMAT_BGRA8:
  45         return format == BGRA_8888 || format == RGBA_4444;
  46     }
  47     NOTREACHED();
  48     return false;
  49   }
  50
  51  private:
  52   DISALLOW_IMPLICIT_CONSTRUCTORS(PlatformColor);
  53 };
  54
  55 }  // namespace cc
  56
  57 #endif  // CC_RESOURCES_PLATFORM_COLOR_H_