cc: Move Layer Id to Node Map to Individual Property Tree Private

cc/trees/property_tree.h

 // Copyright 2014 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_TREES_PROPERTY_TREE_H_
 #define CC_TREES_PROPERTY_TREE_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 35 matching lines @@
 template <typename T>
 class CC_EXPORT PropertyTree {
  public:
   PropertyTree();
   PropertyTree(const PropertyTree& other) = delete;
 
   // These C++ special member functions cannot be implicit inline because
   // they are exported by CC_EXPORT. They will be instantiated in every
   // compilation units that included this header, and compilation can fail
   // because T may be incomplete.
-  ~PropertyTree();
+  virtual ~PropertyTree();
   PropertyTree<T>& operator=(const PropertyTree<T>&);
 
   // Property tree node starts from index 0.
   static const int kInvalidNodeId = -1;
   static const int kRootNodeId = 0;
 
   bool operator==(const PropertyTree<T>& other) const;
 
   int Insert(const T& tree_node, int parent_id);
 
@@ skipping 23 matching lines @@
 
   int next_available_id() const { return static_cast<int>(size()); }
 
   void SetPropertyTrees(PropertyTrees* property_trees) {
     property_trees_ = property_trees;
   }
   PropertyTrees* property_trees() const { return property_trees_; }
 
   void AsValueInto(base::trace_event::TracedValue* value) const;
 
+  T* FindNodeFromOwningId(int id) {
+    return Node(FindNodeIndexFromOwningId(id));
+  }
+  int FindNodeIndexFromOwningId(int id) const {

[pdr., 2017/03/16 20:30:28]

I think we should move away from using the "owning id" term because layers don't
really own nodes anymore. WDYT of switching this to be something like
FindNodeIndexFromLayerId?

+    auto iter = layer_id_to_node_index.find(id);
+    if (iter == layer_id_to_node_index.end())
+      return kInvalidNodeId;
+    else
+      return iter->second;
+  }
+
+  void InsertOwningIdForNode(const T* node, int id) {

[pdr., 2017/03/16 20:30:28]

WDYT of using Set* instead of Insert*?

+    if (!node) {
+      layer_id_to_node_index[id] = kInvalidNodeId;
+      return;
+    }
+
+    DCHECK(node == Node(node->id));
+    layer_id_to_node_index[id] = node->id;
+  }
+
  private:
   std::vector<T> nodes_;
 
+  // These maps map from layer id to the property tree node index.
+  std::unordered_map<int, int> layer_id_to_node_index;
+
   bool needs_update_;
   PropertyTrees* property_trees_;
 };
 
 struct StickyPositionNodeData {
   int scroll_ancestor;
   LayerStickyPositionConstraint constraints;
 
   // This is the offset that blink has already applied to counteract the main
   // thread scroll offset of the scroll ancestor. We need to account for this
   // by computing the additional offset necessary to keep the element stuck.
   gfx::Vector2dF main_thread_offset;
 
   StickyPositionNodeData() : scroll_ancestor(-1) {}
 };
 
 class CC_EXPORT TransformTree final : public PropertyTree<TransformNode> {
  public:
   TransformTree();
 
   // These C++ special member functions cannot be implicit inline because
   // they are exported by CC_EXPORT. They will be instantiated in every
   // compilation units that included this header, and compilation can fail
   // because TransformCachedNodeData may be incomplete.
   TransformTree(const TransformTree&) = delete;
-  ~TransformTree();
+  ~TransformTree() final;
   TransformTree& operator=(const TransformTree&);
 
   bool operator==(const TransformTree& other) const;
 
   static const int kContentsRootNodeId = 1;
 
   int Insert(const TransformNode& tree_node, int parent_id);
 
   void clear();
 
@@ skipping 144 matching lines @@
 
   static const int kViewportNodeId = 1;
 
   void SetViewportClip(gfx::RectF viewport_rect);
   gfx::RectF ViewportClip() const;
 };
 
 class CC_EXPORT EffectTree final : public PropertyTree<EffectNode> {
  public:
   EffectTree();
-  ~EffectTree();
+  ~EffectTree() final;
 
   EffectTree& operator=(const EffectTree& from);
   bool operator==(const EffectTree& other) const;
 
   static const int kContentsRootNodeId = 1;
 
   int Insert(const EffectNode& tree_node, int parent_id);
 
   void clear();
 
@@ skipping 59 matching lines @@
   // Unsorted list of all mask layer ids that effect nodes refer to.
   std::vector<int> mask_layer_ids_;
 
   // Indexed by node id.
   std::vector<std::unique_ptr<RenderSurfaceImpl>> render_surfaces_;
 };
 
 class CC_EXPORT ScrollTree final : public PropertyTree<ScrollNode> {
  public:
   ScrollTree();
-  ~ScrollTree();
+  ~ScrollTree() final;
 
   ScrollTree& operator=(const ScrollTree& from);
   bool operator==(const ScrollTree& other) const;
 
   void clear();
 
   gfx::ScrollOffset MaxScrollOffset(int scroll_node_id) const;
   void OnScrollOffsetAnimated(int layer_id,
                               int scroll_tree_index,
                               const gfx::ScrollOffset& scroll_offset,
@@ skipping 174 matching lines @@
 
 class CC_EXPORT PropertyTrees final {
  public:
   PropertyTrees();
   PropertyTrees(const PropertyTrees& other) = delete;
   ~PropertyTrees();
 
   bool operator==(const PropertyTrees& other) const;
   PropertyTrees& operator=(const PropertyTrees& from);
 
-  // These maps map from layer id to the index for each of the respective
-  // property node types.
-  std::unordered_map<int, int> layer_id_to_transform_node_index;
-  std::unordered_map<int, int> layer_id_to_effect_node_index;
-  std::unordered_map<int, int> layer_id_to_clip_node_index;
-  std::unordered_map<int, int> layer_id_to_scroll_node_index;
-  enum TreeType { TRANSFORM, EFFECT, CLIP, SCROLL };
-
   // These maps allow mapping directly from a compositor element id to the
   // respective property node. This will eventually allow simplifying logic in
   // various places that today has to map from element id to layer id, and then
   // from layer id to the respective property node. Completing that work is
   // pending the launch of Slimming Paint v2 and reworking UI compositor logic
   // to produce cc property trees and these maps.
   std::unordered_map<ElementId, int, ElementIdHash>
       element_id_to_effect_node_index;
   std::unordered_map<ElementId, int, ElementIdHash>
       element_id_to_scroll_node_index;
@@ skipping 22 matching lines @@
   bool is_main_thread;
   bool is_active;
 
   void clear();
 
   void SetInnerViewportContainerBoundsDelta(gfx::Vector2dF bounds_delta);
   void SetOuterViewportContainerBoundsDelta(gfx::Vector2dF bounds_delta);
   void SetInnerViewportScrollBoundsDelta(gfx::Vector2dF bounds_delta);
   void PushOpacityIfNeeded(PropertyTrees* target_tree);
   void RemoveIdFromIdToIndexMaps(int id);
-  bool IsInIdToIndexMap(TreeType tree_type, int id);
   void UpdateChangeTracking();
   void PushChangeTrackingTo(PropertyTrees* tree);
   void ResetAllChangeTracking();
 
   gfx::Vector2dF inner_viewport_container_bounds_delta() const {
     return inner_viewport_container_bounds_delta_;
   }
 
   gfx::Vector2dF outer_viewport_container_bounds_delta() const {
     return outer_viewport_container_bounds_delta_;
@@ skipping 33 matching lines @@
   DrawTransforms& GetDrawTransforms(int transform_id, int effect_id) const;
   DrawTransformData& FetchDrawTransformsDataFromCache(int transform_id,
                                                       int effect_id) const;
 
   PropertyTreesCachedData cached_data_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_PROPERTY_TREE_H_