nine_patch_layer_impl.h

// 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.

#ifndef CC_LAYERS_NINE_PATCH_LAYER_IMPL_H_
#define CC_LAYERS_NINE_PATCH_LAYER_IMPL_H_

#include <string>

#include "cc/base/cc_export.h"
#include "cc/layers/layer_impl.h"
#include "cc/layers/ui_resource_layer_impl.h"
#include "cc/resources/resource_provider.h"
#include "cc/resources/ui_resource_client.h"
#include "ui/gfx/rect.h"
#include "ui/gfx/size.h"

namespace base {
class DictionaryValue;
}

namespace cc {

class CC_EXPORT NinePatchLayerImpl : public UIResourceLayerImpl {
 public:
  static scoped_ptr<NinePatchLayerImpl> Create(LayerTreeImpl* tree_impl,
                                               int id) {
    return make_scoped_ptr(new NinePatchLayerImpl(tree_impl, id));
  }
  virtual ~NinePatchLayerImpl();

  // The bitmap stretches out the bounds of the layer.  The following picture
  // illustrates the parameters associated with the dimensions.
  //
  // Layer space layout              Bitmap space layout
  //
  // ------------------------       ~~~~~~~~~~ W ~~~~~~~~~~
  // |          :           |       :     :                |
  // |          C           |       :     Y                |
  // |          :           |       :     :                |
  // |     ------------     |       :~~X~~------------     |
  // |     |          |     |       :     |          :     |
  // |     |          |     |       :     |          :     |
  // |~~A~~|          |~~B~~|       H     |          Q     |
  // |     |          |     |       :     |          :     |
  // |     ------------     |       :     ~~~~~P~~~~~      |
  // |          :           |       :                      |
  // |          D           |       :                      |
  // |          :           |       :                      |
  // ------------------------       ------------------------
  //
  // |image_bounds| = (W, H)
  // |image_aperture| = (X, Y, P, Q)
  // |border| = (A, C, A + B, C + D)
  // |fill_center| indicates whether to draw the center quad or not.
  void SetLayout(const gfx::Rect& image_aperture,
                 const gfx::Rect& border,
                 bool fill_center);

  virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl)
      OVERRIDE;
  virtual void PushPropertiesTo(LayerImpl* layer) OVERRIDE;

  virtual void AppendQuads(RenderPass* render_pass,
                           const OcclusionTracker<LayerImpl>& occlusion_tracker,
                           AppendQuadsData* append_quads_data) OVERRIDE;

  virtual base::DictionaryValue* LayerTreeAsJson() const OVERRIDE;

 protected:
  NinePatchLayerImpl(LayerTreeImpl* tree_impl, int id);

 private:
  virtual const char* LayerTypeAsString() const OVERRIDE;

  void CheckGeometryLimitations();

  // The transparent center region that shows the parent layer's contents in
  // image space.
  gfx::Rect image_aperture_;

  // An inset border that the patches will be mapped to.
  gfx::Rect border_;

  bool fill_center_;

  DISALLOW_COPY_AND_ASSIGN(NinePatchLayerImpl);
};

}  // namespace cc

#endif  // CC_LAYERS_NINE_PATCH_LAYER_IMPL_H_