contents_scaling_layer.h revision 7dbb3d5cf0c15f500944d211057644d6a2f37371 
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_LAYERS_CONTENTS_SCALING_LAYER_H_
6#define CC_LAYERS_CONTENTS_SCALING_LAYER_H_
7
8#include "cc/base/cc_export.h"
9#include "cc/layers/layer.h"
10
11namespace cc {
12
13// Base class for layers that need contents scale.
14// The content bounds are determined by bounds and scale of the contents.
15class CC_EXPORT ContentsScalingLayer : public Layer {
16 public:
17  virtual void CalculateContentsScale(
18      float ideal_contents_scale,
19      float device_scale_factor,
20      float page_scale_factor,
21      bool animating_transform_to_screen,
22      float* contents_scale_x,
23      float* contents_scale_y,
24      gfx::Size* content_bounds) OVERRIDE;
25
26  virtual bool Update(
27    ResourceUpdateQueue* queue,
28    const OcclusionTracker* occlusion) OVERRIDE;
29
30 protected:
31  ContentsScalingLayer();
32  virtual ~ContentsScalingLayer();
33
34  gfx::Size ComputeContentBoundsForScale(float scale_x, float scale_y) const;
35
36 private:
37  float last_update_contents_scale_x_;
38  float last_update_contents_scale_y_;
39
40  DISALLOW_COPY_AND_ASSIGN(ContentsScalingLayer);
41};
42
43}  // namespace cc
44
45#endif  // CC_LAYERS_CONTENTS_SCALING_LAYER_H__
46