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// 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_RESOURCES_SKPICTURE_CONTENT_LAYER_UPDATER_H_
#define CC_RESOURCES_SKPICTURE_CONTENT_LAYER_UPDATER_H_

#include "cc/resources/content_layer_updater.h"
#include "third_party/skia/include/core/SkPicture.h"

class SkCanvas;

namespace cc {

class LayerPainter;

// This class records the content_rect into an SkPicture. Subclasses, provide
// different implementations of tile updating based on this recorded picture.
// The BitmapSkPictureContentLayerUpdater and
// FrameBufferSkPictureContentLayerUpdater are two examples of such
// implementations.
class SkPictureContentLayerUpdater : public ContentLayerUpdater {
 protected:
  SkPictureContentLayerUpdater(
      scoped_ptr<LayerPainter> painter,
      RenderingStatsInstrumentation* stats_instrumentation,
      int layer_id);
  virtual ~SkPictureContentLayerUpdater();

  virtual void PrepareToUpdate(gfx::Rect content_rect,
                               gfx::Size tile_size,
                               float contents_width_scale,
                               float contents_height_scale,
                               gfx::Rect* resulting_opaque_rect) OVERRIDE;
  void DrawPicture(SkCanvas* canvas);

 private:
  // Recording canvas.
  SkPicture picture_;

  DISALLOW_COPY_AND_ASSIGN(SkPictureContentLayerUpdater);
};

}  // namespace cc

#endif  // CC_RESOURCES_SKPICTURE_CONTENT_LAYER_UPDATER_H_