content/browser/android/edge_effect.h

   1 // Copyright (c) 2013 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 CONTENT_BROWSER_ANDROID_EDGE_EFFECT_H_
   6 #define CONTENT_BROWSER_ANDROID_EDGE_EFFECT_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/time/time.h"
  11 #include "ui/gfx/size_f.h"
  12
  13 namespace cc {
  14 class Layer;
  15 }
  16
  17 namespace content {
  18
  19 /* |EdgeEffect| mirrors its Android counterpart, EdgeEffect.java.
  20  * The primary difference is ownership; the Android version manages render
  21  * resources directly, while this version simply applies the effect to
  22  * existing resources. Conscious tradeoffs were made to align this as closely
  23  * as possible with the original Android java version.
  24  * All coordinates and dimensions are in device pixels.
  25  */
  26 class EdgeEffect {
  27 public:
  28   enum Edge {
  29     EDGE_TOP = 0,
  30     EDGE_LEFT,
  31     EDGE_BOTTOM,
  32     EDGE_RIGHT,
  33     EDGE_COUNT
  34   };
  35
  36   EdgeEffect(scoped_refptr<cc::Layer> edge, scoped_refptr<cc::Layer> glow);
  37   ~EdgeEffect();
  38
  39   void Pull(base::TimeTicks current_time, float delta_distance);
  40   void Absorb(base::TimeTicks current_time, float velocity);
  41   bool Update(base::TimeTicks current_time);
  42   void Release(base::TimeTicks current_time);
  43
  44   void Finish();
  45   bool IsFinished() const;
  46
  47   void ApplyToLayers(gfx::SizeF window_size,
  48                      Edge edge,
  49                      float edge_height,
  50                      float glow_height,
  51                      float offset);
  52
  53 private:
  54
  55   enum State {
  56     STATE_IDLE = 0,
  57     STATE_PULL,
  58     STATE_ABSORB,
  59     STATE_RECEDE,
  60     STATE_PULL_DECAY
  61   };
  62
  63   scoped_refptr<cc::Layer> edge_;
  64   scoped_refptr<cc::Layer> glow_;
  65
  66   float edge_alpha_;
  67   float edge_scale_y_;
  68   float glow_alpha_;
  69   float glow_scale_y_;
  70
  71   float edge_alpha_start_;
  72   float edge_alpha_finish_;
  73   float edge_scale_y_start_;
  74   float edge_scale_y_finish_;
  75   float glow_alpha_start_;
  76   float glow_alpha_finish_;
  77   float glow_scale_y_start_;
  78   float glow_scale_y_finish_;
  79
  80   base::TimeTicks start_time_;
  81   base::TimeDelta duration_;
  82
  83   State state_;
  84
  85   float pull_distance_;
  86
  87   DISALLOW_COPY_AND_ASSIGN(EdgeEffect);
  88 };
  89
  90 }  // namespace content
  91
  92 #endif  // CONTENT_BROWSER_ANDROID_EDGE_EFFECT_H_