cc/layers/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_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
  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   void CalculateContentsScale(float ideal_contents_scale,
  18                               float* contents_scale_x,
  19                               float* contents_scale_y,
  20                               gfx::Size* content_bounds) override;
  21
  22   bool Update(ResourceUpdateQueue* queue,
  23               const OcclusionTracker<Layer>* occlusion) override;
  24
  25  protected:
  26   ContentsScalingLayer();
  27   ~ContentsScalingLayer() override;
  28
  29   gfx::Size ComputeContentBoundsForScale(float scale_x, float scale_y) const;
  30
  31  private:
  32   float last_update_contents_scale_x_;
  33   float last_update_contents_scale_y_;
  34
  35   DISALLOW_COPY_AND_ASSIGN(ContentsScalingLayer);
  36 };
  37
  38 }  // namespace cc
  39
  40 #endif  // CC_LAYERS_CONTENTS_SCALING_LAYER_H__