cc/contents_scaling_layer.h

   1 // Copyright 2012 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_CONTENTS_SCALING_LAYER_H_
   6 #define CC_CONTENTS_SCALING_LAYER_H_
   7
   8 #include "cc/cc_export.h"
   9 #include "cc/layer.h"
  10
  11 namespace cc {
  12
  13 // Base class for layers that need contents scale.
  14 // The content bounds are determined by bounds and scale of the contents.
  15 class CC_EXPORT ContentsScalingLayer : public Layer {
  16  public:
  17   virtual void calculateContentsScale(
  18       float ideal_contents_scale,
  19       float* contents_scale_x,
  20       float* contents_scale_y,
  21       gfx::Size* content_bounds) OVERRIDE;
  22   virtual void didUpdateBounds() OVERRIDE;
  23
  24   virtual void update(
  25     ResourceUpdateQueue& queue,
  26     const OcclusionTracker* occlusion,
  27     RenderingStats& stats) OVERRIDE;
  28
  29  protected:
  30   ContentsScalingLayer();
  31   virtual ~ContentsScalingLayer();
  32
  33   gfx::Size computeContentBoundsForScale(float scaleX, float scaleY) const;
  34
  35  private:
  36   float last_update_contents_scale_x_;
  37   float last_update_contents_scale_y_;
  38 };
  39
  40 }  // namespace cc
  41
  42 #endif  // CC_CONTENTS_SCALING_LAYER_H__