cc: Async readback.

cc/quads/render_pass.h

 // Copyright 2011 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.
 
 #ifndef CC_QUADS_RENDER_PASS_H_
 #define CC_QUADS_RENDER_PASS_H_
 
 #include <utility>
 #include <vector>
 
 #include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/hash_tables.h"

[piman, 2013/04/26 00:15:02]

nit: not using this

 #include "cc/base/cc_export.h"
 #include "cc/base/hash_pair.h"
 #include "cc/base/scoped_ptr_hash_map.h"
 #include "cc/base/scoped_ptr_vector.h"
 #include "skia/ext/refptr.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebFilterOperations.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkImageFilter.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/rect_f.h"
@@ skipping 68 matching lines @@
   // render pass' |output_rect|.
   gfx::Transform transform_to_root_target;
 
   // If false, the pixels in the render pass' texture are all opaque.
   bool has_transparent_background;
 
   // If true, then there may be pixels in the render pass' texture that are not
   // complete, since they are occluded.
   bool has_occlusion_from_outside_target_surface;
 
+  // If non-empty, the renderer should produce a copy of the render pass'
+  // contents as a bitmap, and give a copy of the bitmap to each callback in
+  // this list. This property should not be serialized between compositors, as
+  // it only makes sense in the root compositor.
+  typedef base::Callback<void(scoped_ptr<SkBitmap>)>
+      RequestCopyAsBitmapCallback;
+  std::vector<RequestCopyAsBitmapCallback> copy_callbacks;
+
   QuadList quad_list;
   SharedQuadStateList shared_quad_state_list;
 
  protected:
   RenderPass();
 
   DISALLOW_COPY_AND_ASSIGN(RenderPass);
 };
 
 }  // namespace cc
@@ skipping 17 matching lines @@
 #error define a hash function for your compiler
 #endif  // COMPILER
 }
 
 namespace cc {
 typedef ScopedPtrVector<RenderPass> RenderPassList;
 typedef base::hash_map<RenderPass::Id, RenderPass*> RenderPassIdHashMap;
 }  // namespace cc
 
 #endif  // CC_QUADS_RENDER_PASS_H_