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   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__