cc: Adding support for RGBA_4444 tile textures

cc/resources/resource.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/resources/resource.h"
 #include "third_party/khronos/GLES2/gl2ext.h"
 
 namespace cc {
 
 size_t Resource::bytes() const {
   if (size_.IsEmpty())
     return 0;
 
-  return MemorySizeBytes(size_, format_);
+  return MemorySizeBytes(size_, format_, is_16_bit_resource_);
 }
 
-size_t Resource::BytesPerPixel(GLenum format) {
+size_t Resource::BytesPerPixel(GLenum format, bool is_16_bit_resource) {

[epennerAtGoogle, 2013/09/05 01:54:15]

Could we just pass in the GL type here rather than the extra boolean? And then
DCHECK that only the supported combos of format/type are passed in?

[Sami, 2013/09/05 14:13:26]

+1, I think that would make this a lot cleaner.

[kaanb, 2013/09/06 02:05:54]

On my TODO list for tomorrow.

   size_t components_per_pixel = 0;
   size_t bytes_per_component = 1;
   switch (format) {
     case GL_RGBA:
+      components_per_pixel = (is_16_bit_resource) ? 2 : 4;
+      break;
     case GL_BGRA_EXT:
       components_per_pixel = 4;
       break;
     case GL_LUMINANCE:
       components_per_pixel = 1;
       break;
     default:
       NOTREACHED();
   }
   return components_per_pixel * bytes_per_component;
 }
 
-size_t Resource::MemorySizeBytes(gfx::Size size, GLenum format) {
-  return BytesPerPixel(format) * size.width() * size.height();
+size_t Resource::MemorySizeBytes(
+    gfx::Size size, GLenum format, bool is_16_bit_resource) {
+  return
+      BytesPerPixel(format, is_16_bit_resource) * size.width() * size.height();
 }
 
 
 }  // namespace cc