CC Animations: Establish AnimationHost, AnimationTimeline and AnimationPlayer

cc/animation/animation_player.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CC_ANIMATION_ANIMATION_PLAYER_H_
+#define CC_ANIMATION_ANIMATION_PLAYER_H_
+
+#include "base/memory/ref_counted.h"
+#include "cc/animation/layer_animation_controller.h"
+#include "cc/animation/layer_animation_value_observer.h"
+#include "cc/animation/layer_animation_value_provider.h"
+#include "cc/base/cc_export.h"
+
+namespace gfx {
+class ScrollOffset;
+class Transform;
+}
+
+namespace cc {
+
+class AnimationHost;
+class AnimationTimeline;
+class FilterOperations;
+class Layer;
+
+// An AnimationPlayer owns all animations to be run on particular CC Layer.
+// Multiple AnimationPlayers can be attached to one layer. In this case,
+// they share common LayerAnimationController (temp solution) so the
+// LayerAnimationController-to-Layer relationship stays the same (1:1, LACs
+// have same IDs as their correspondent Layers).
+// For now, the blink logic is responsible for handling conflicting
+// same-property animations.
+// Each AnimationPlayer has it's copy on the impl thread.
+// This is a CC counterpart for blink::AnimationPlayer (in 1:1 relationship).
+class CC_EXPORT AnimationPlayer : public base::RefCounted<AnimationPlayer>,

[Ian Vollick, 2015/05/05 03:52:06]

Why RefCounted?

[loyso (OOO), 2015/05/05 06:51:18]

It's in shared ownership between blink::AnimationPlayer and
cc::AnimationTimeline/cc::AnimationHost(=Registrar). Same idea as for cc::Layer.

[Ian Vollick, 2015/05/07 13:58:42]

This is probably a dumb question, but can players outlive their timelines or be
created before them?

[loyso (OOO), 2015/05/08 01:04:35]

Yes, sure. Typically you create them in blink in advance. So you can attach it
to an element and add animations later.

[loyso (OOO), 2015/06/22 07:48:51]

Class diagrams added to the design doc.

[Ian Vollick, 2015/06/22 13:58:39]

These diagrams are amazing. Thank you!

+                                  public LayerAnimationValueProvider {
+ public:
+  static scoped_refptr<AnimationPlayer> Create(int id);
+  scoped_refptr<AnimationPlayer> CreateImplInstance() const;
+
+  int id() const { return id_; }
+  int layer_id() const { return layer_id_; }
+
+  // Parent AnimationHost. AnimationPlayer can be detached from
+  // AnimationTimeline.
+  AnimationHost* animation_host() { return animation_host_; }
+  const AnimationHost* animation_host() const { return animation_host_; }
+  void SetAnimationHost(AnimationHost* animation_host);
+
+  // Parent AnimationTimeline.
+  AnimationTimeline* animation_timeline() { return animation_timeline_; }
+  const AnimationTimeline* animation_timeline() const {
+    return animation_timeline_;
+  }
+  void SetAnimationTimeline(AnimationTimeline* timeline);
+
+  LayerAnimationController* layer_animation_controller() const {
+    return layer_animation_controller_.get();
+  }
+
+  void set_layer_animation_delegate(AnimationDelegate* delegate);
+
+  void AttachLayer(int layer_id);
+  void DetachLayer();
+
+  void LayerRegistered(int layer_id, bool is_active_tree);
+  void LayerUnregistered(int layer_id, bool is_active_tree);
+
+  void AddAnimation(scoped_ptr<Animation> animation);
+  void PauseAnimation(int animation_id, double time_offset);
+  void RemoveAnimation(int animation_id);
+
+  void PushPropertiesTo(AnimationPlayer* player_impl);
+
+  bool has_active_value_observer_for_testing() const {
+    return active_value_observer_;
+  }
+  bool has_pending_value_observer_for_testing() const {
+    return pending_value_observer_;
+  }
+
+ private:
+  friend class base::RefCounted<AnimationPlayer>;
+
+  explicit AnimationPlayer(int id);
+  ~AnimationPlayer() override;
+
+  void SetNeedsCommit();
+
+  void SetFilterMutated(bool active_tree, const FilterOperations& filters);
+  void SetOpacityMutated(bool active_tree, float opacity);
+  void SetTransformMutated(bool active_tree, const gfx::Transform& transform);
+  void SetScrollOffsetMutated(bool active_tree,
+                              const gfx::ScrollOffset& scroll_offset);
+
+  void AddControllerToTimeline();
+  void RemoveControllerFromTimeline();
+
+  void CreateActiveValueObserver();
+  void DestroyActiveValueObserver();
+
+  void CreatePendingValueObserver();
+  void DestroyPendingValueObserver();
+
+  // LayerAnimationValueProvider implementation.
+  gfx::ScrollOffset ScrollOffsetForAnimation() const override;
+
+  class ValueObserver;
+  scoped_ptr<ValueObserver> active_value_observer_;
+  scoped_ptr<ValueObserver> pending_value_observer_;
+
+  scoped_refptr<LayerAnimationController> layer_animation_controller_;
+  AnimationHost* animation_host_;
+  AnimationTimeline* animation_timeline_;
+  AnimationDelegate* layer_animation_delegate_;
+
+  int id_;
+  int layer_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(AnimationPlayer);
+};
+
+}  // namespace cc
+
+#endif  // CC_ANIMATION_ANIMATION_PLAYER_H_