cc/animation/animation.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_ANIMATION_ANIMATION_H_
   6 #define CC_ANIMATION_ANIMATION_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "cc/base/cc_export.h"
  11
  12 namespace cc {
  13
  14 class AnimationCurve;
  15
  16 // An Animation contains all the state required to play an AnimationCurve.
  17 // Specifically, the affected property, the run state (paused, finished, etc.),
  18 // loop count, last pause time, and the total time spent paused.
  19 class CC_EXPORT Animation {
  20  public:
  21   // Animations begin in the 'WaitingForTargetAvailability' state. An Animation
  22   // waiting for target availibility will run as soon as its target property
  23   // is free (and all the animations animating with it are also able to run).
  24   // When this time arrives, the controller will move the animation into the
  25   // Starting state, and then into the Running state. Running animations may
  26   // toggle between Running and Paused, and may be stopped by moving into either
  27   // the Aborted or Finished states. A Finished animation was allowed to run to
  28   // completion, but an Aborted animation was not.
  29   enum RunState {
  30     WaitingForTargetAvailability = 0,
  31     WaitingForDeletion,
  32     Starting,
  33     Running,
  34     Paused,
  35     Finished,
  36     Aborted,
  37     // This sentinel must be last.
  38     RunStateEnumSize
  39   };
  40
  41   enum TargetProperty {
  42     Transform = 0,
  43     Opacity,
  44     Filter,
  45     ScrollOffset,
  46     BackgroundColor,
  47     // This sentinel must be last.
  48     TargetPropertyEnumSize
  49   };
  50
  51   enum Direction { Normal, Reverse, Alternate, AlternateReverse };
  52
  53   static scoped_ptr<Animation> Create(scoped_ptr<AnimationCurve> curve,
  54                                       int animation_id,
  55                                       int group_id,
  56                                       TargetProperty target_property);
  57
  58   virtual ~Animation();
  59
  60   int id() const { return id_; }
  61   int group() const { return group_; }
  62   TargetProperty target_property() const { return target_property_; }
  63
  64   RunState run_state() const { return run_state_; }
  65   void SetRunState(RunState run_state, double monotonic_time);
  66
  67   // This is the number of times that the animation will play. If this
  68   // value is zero the animation will not play. If it is negative, then
  69   // the animation will loop indefinitely.
  70   int iterations() const { return iterations_; }
  71   void set_iterations(int n) { iterations_ = n; }
  72
  73   double start_time() const { return start_time_; }
  74   void set_start_time(double monotonic_time) { start_time_ = monotonic_time; }
  75   bool has_set_start_time() const { return !!start_time_; }
  76
  77   double time_offset() const { return time_offset_; }
  78   void set_time_offset(double monotonic_time) { time_offset_ = monotonic_time; }
  79
  80   void Suspend(double monotonic_time);
  81   void Resume(double monotonic_time);
  82
  83   Direction direction() { return direction_; }
  84   void set_direction(Direction direction) { direction_ = direction; }
  85
  86   bool IsFinishedAt(double monotonic_time) const;
  87   bool is_finished() const {
  88     return run_state_ == Finished ||
  89         run_state_ == Aborted ||
  90         run_state_ == WaitingForDeletion;
  91   }
  92
  93   AnimationCurve* curve() { return curve_.get(); }
  94   const AnimationCurve* curve() const { return curve_.get(); }
  95
  96   // If this is true, even if the animation is running, it will not be tickable
  97   // until it is given a start time. This is true for animations running on the
  98   // main thread.
  99   bool needs_synchronized_start_time() const {
 100     return needs_synchronized_start_time_;
 101   }
 102   void set_needs_synchronized_start_time(bool needs_synchronized_start_time) {
 103     needs_synchronized_start_time_ = needs_synchronized_start_time;
 104   }
 105
 106   // This is true for animations running on the main thread when the Finished
 107   // event sent by the corresponding impl animation has been received.
 108   bool received_finished_event() const {
 109     return received_finished_event_;
 110   }
 111   void set_received_finished_event(bool received_finished_event) {
 112     received_finished_event_ = received_finished_event;
 113   }
 114
 115   // Takes the given absolute time, and using the start time and the number
 116   // of iterations, returns the relative time in the current iteration.
 117   double TrimTimeToCurrentIteration(double monotonic_time) const;
 118
 119   scoped_ptr<Animation> CloneAndInitialize(RunState initial_run_state) const;
 120   bool is_controlling_instance() const { return is_controlling_instance_; }
 121
 122   void PushPropertiesTo(Animation* other) const;
 123
 124   void set_is_impl_only(bool is_impl_only) { is_impl_only_ = is_impl_only; }
 125   bool is_impl_only() const { return is_impl_only_; }
 126
 127   void set_affects_active_observers(bool affects_active_observers) {
 128     affects_active_observers_ = affects_active_observers;
 129   }
 130   bool affects_active_observers() const { return affects_active_observers_; }
 131
 132   void set_affects_pending_observers(bool affects_pending_observers) {
 133     affects_pending_observers_ = affects_pending_observers;
 134   }
 135   bool affects_pending_observers() const { return affects_pending_observers_; }
 136
 137  private:
 138   Animation(scoped_ptr<AnimationCurve> curve,
 139             int animation_id,
 140             int group_id,
 141             TargetProperty target_property);
 142
 143   scoped_ptr<AnimationCurve> curve_;
 144
 145   // IDs are not necessarily unique.
 146   int id_;
 147
 148   // Animations that must be run together are called 'grouped' and have the same
 149   // group id. Grouped animations are guaranteed to start at the same time and
 150   // no other animations may animate any of the group's target properties until
 151   // all animations in the group have finished animating. Note: an active
 152   // animation's group id and target property uniquely identify that animation.
 153   int group_;
 154
 155   TargetProperty target_property_;
 156   RunState run_state_;
 157   int iterations_;
 158   double start_time_;
 159   Direction direction_;
 160
 161   // The time offset effectively pushes the start of the animation back in time.
 162   // This is used for resuming paused animations -- an animation is added with a
 163   // non-zero time offset, causing the animation to skip ahead to the desired
 164   // point in time.
 165   double time_offset_;
 166
 167   bool needs_synchronized_start_time_;
 168   bool received_finished_event_;
 169
 170   // When an animation is suspended, it behaves as if it is paused and it also
 171   // ignores all run state changes until it is resumed. This is used for testing
 172   // purposes.
 173   bool suspended_;
 174
 175   // These are used in TrimTimeToCurrentIteration to account for time
 176   // spent while paused. This is not included in AnimationState since it
 177   // there is absolutely no need for clients of this controller to know
 178   // about these values.
 179   double pause_time_;
 180   double total_paused_time_;
 181
 182   // Animations lead dual lives. An active animation will be conceptually owned
 183   // by two controllers, one on the impl thread and one on the main. In reality,
 184   // there will be two separate Animation instances for the same animation. They
 185   // will have the same group id and the same target property (these two values
 186   // uniquely identify an animation). The instance on the impl thread is the
 187   // instance that ultimately controls the values of the animating layer and so
 188   // we will refer to it as the 'controlling instance'.
 189   bool is_controlling_instance_;
 190
 191   bool is_impl_only_;
 192
 193   // When pushed from a main-thread controller to a compositor-thread
 194   // controller, an animation will initially only affect pending observers
 195   // (corresponding to layers in the pending tree). Animations that only
 196   // affect pending observers are able to reach the Starting state and tick
 197   // pending observers, but cannot proceed any further and do not tick active
 198   // observers. After activation, such animations affect both kinds of observers
 199   // and are able to proceed past the Starting state. When the removal of
 200   // an animation is pushed from a main-thread controller to a
 201   // compositor-thread controller, this initially only makes the animation
 202   // stop affecting pending observers. After activation, such animations no
 203   // longer affect any observers, and are deleted.
 204   bool affects_active_observers_;
 205   bool affects_pending_observers_;
 206
 207   DISALLOW_COPY_AND_ASSIGN(Animation);
 208 };
 209
 210 }  // namespace cc
 211
 212 #endif  // CC_ANIMATION_ANIMATION_H_