Clarify property tree id-to-index map names.

cc/trees/property_tree.cc

 // 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.
 
 #include <stddef.h>
 
 #include <set>
 #include <vector>
 
 #include "base/logging.h"
@@ skipping 1514 matching lines @@
   clip_tree.SetPropertyTrees(this);
   scroll_tree.SetPropertyTrees(this);
 }
 
 PropertyTrees::~PropertyTrees() {}
 
 bool PropertyTrees::operator==(const PropertyTrees& other) const {
   return transform_tree == other.transform_tree &&
          effect_tree == other.effect_tree && clip_tree == other.clip_tree &&
          scroll_tree == other.scroll_tree &&
-         transform_id_to_index_map == other.transform_id_to_index_map &&
-         effect_id_to_index_map == other.effect_id_to_index_map &&
-         clip_id_to_index_map == other.clip_id_to_index_map &&
-         scroll_id_to_index_map == other.scroll_id_to_index_map &&
+         layer_id_to_transform_node_index ==
+             other.layer_id_to_transform_node_index &&
+         layer_id_to_effect_node_index == other.layer_id_to_effect_node_index &&
+         layer_id_to_clip_node_index == other.layer_id_to_clip_node_index &&
+         layer_id_to_scroll_node_index == other.layer_id_to_scroll_node_index &&
          always_use_active_tree_opacity_effect_ids ==
              other.always_use_active_tree_opacity_effect_ids &&
          needs_rebuild == other.needs_rebuild && changed == other.changed &&
          full_tree_damaged == other.full_tree_damaged &&
          is_main_thread == other.is_main_thread &&
          is_active == other.is_active &&
          non_root_surfaces_enabled == other.non_root_surfaces_enabled &&
          sequence_number == other.sequence_number;
 }
 
 PropertyTrees& PropertyTrees::operator=(const PropertyTrees& from) {
   transform_tree = from.transform_tree;
   effect_tree = from.effect_tree;
   clip_tree = from.clip_tree;
   scroll_tree = from.scroll_tree;
-  transform_id_to_index_map = from.transform_id_to_index_map;
-  effect_id_to_index_map = from.effect_id_to_index_map;
+  layer_id_to_transform_node_index = from.layer_id_to_transform_node_index;
+  layer_id_to_effect_node_index = from.layer_id_to_effect_node_index;
   always_use_active_tree_opacity_effect_ids =
       from.always_use_active_tree_opacity_effect_ids;
-  clip_id_to_index_map = from.clip_id_to_index_map;
-  scroll_id_to_index_map = from.scroll_id_to_index_map;
+  layer_id_to_clip_node_index = from.layer_id_to_clip_node_index;
+  layer_id_to_scroll_node_index = from.layer_id_to_scroll_node_index;
   needs_rebuild = from.needs_rebuild;
   changed = from.changed;
   full_tree_damaged = from.full_tree_damaged;
   non_root_surfaces_enabled = from.non_root_surfaces_enabled;
   sequence_number = from.sequence_number;
   is_main_thread = from.is_main_thread;
   is_active = from.is_active;
   inner_viewport_container_bounds_delta_ =
       from.inner_viewport_container_bounds_delta();
   outer_viewport_container_bounds_delta_ =
       from.outer_viewport_container_bounds_delta();
   inner_viewport_scroll_bounds_delta_ =
       from.inner_viewport_scroll_bounds_delta();
   transform_tree.SetPropertyTrees(this);
   effect_tree.SetPropertyTrees(this);
   clip_tree.SetPropertyTrees(this);
   scroll_tree.SetPropertyTrees(this);
   ResetCachedData();
   return *this;
 }
 
 void PropertyTrees::clear() {
   transform_tree.clear();
   clip_tree.clear();
   effect_tree.clear();
   scroll_tree.clear();
-  transform_id_to_index_map.clear();
-  effect_id_to_index_map.clear();
-  clip_id_to_index_map.clear();
-  scroll_id_to_index_map.clear();
+  layer_id_to_transform_node_index.clear();
+  layer_id_to_effect_node_index.clear();
+  layer_id_to_clip_node_index.clear();
+  layer_id_to_scroll_node_index.clear();
   always_use_active_tree_opacity_effect_ids.clear();
 
   needs_rebuild = true;
   full_tree_damaged = false;
   changed = false;
   non_root_surfaces_enabled = true;
   sequence_number++;
 
 #if DCHECK_IS_ON()
   PropertyTrees tree;
@@ skipping 33 matching lines @@
   transform_tree.UpdateOuterViewportContainerBoundsDelta();
 }
 
 void PropertyTrees::SetInnerViewportScrollBoundsDelta(
     gfx::Vector2dF bounds_delta) {
   inner_viewport_scroll_bounds_delta_ = bounds_delta;
 }
 
 void PropertyTrees::PushOpacityIfNeeded(PropertyTrees* target_tree) {
   for (int id : target_tree->always_use_active_tree_opacity_effect_ids) {
-    if (effect_id_to_index_map.find(id) == effect_id_to_index_map.end())
+    if (layer_id_to_effect_node_index.find(id) ==
+        layer_id_to_effect_node_index.end())
       continue;
     EffectNode* source_effect_node =
-        effect_tree.Node(effect_id_to_index_map[id]);
-    EffectNode* target_effect_node =
-        target_tree->effect_tree.Node(target_tree->effect_id_to_index_map[id]);
+        effect_tree.Node(layer_id_to_effect_node_index[id]);
+    EffectNode* target_effect_node = target_tree->effect_tree.Node(
+        target_tree->layer_id_to_effect_node_index[id]);
     float source_opacity = source_effect_node->opacity;
     float target_opacity = target_effect_node->opacity;
     if (source_opacity == target_opacity)
       continue;
     target_effect_node->opacity = source_opacity;
     target_tree->effect_tree.set_needs_update(true);
   }
 }
 
 void PropertyTrees::RemoveIdFromIdToIndexMaps(int id) {
-  transform_id_to_index_map.erase(id);
-  effect_id_to_index_map.erase(id);
-  clip_id_to_index_map.erase(id);
-  scroll_id_to_index_map.erase(id);
+  layer_id_to_transform_node_index.erase(id);
+  layer_id_to_effect_node_index.erase(id);
+  layer_id_to_clip_node_index.erase(id);
+  layer_id_to_scroll_node_index.erase(id);
 }
 
 bool PropertyTrees::IsInIdToIndexMap(TreeType tree_type, int id) {
   std::unordered_map<int, int>* id_to_index_map = nullptr;
   switch (tree_type) {
     case TRANSFORM:
-      id_to_index_map = &transform_id_to_index_map;
+      id_to_index_map = &layer_id_to_transform_node_index;
       break;
     case EFFECT:
-      id_to_index_map = &effect_id_to_index_map;
+      id_to_index_map = &layer_id_to_effect_node_index;
       break;
     case CLIP:
-      id_to_index_map = &clip_id_to_index_map;
+      id_to_index_map = &layer_id_to_clip_node_index;
       break;
     case SCROLL:
-      id_to_index_map = &scroll_id_to_index_map;
+      id_to_index_map = &layer_id_to_scroll_node_index;
       break;
   }
   return id_to_index_map->find(id) != id_to_index_map->end();
 }
 
 void PropertyTrees::UpdateChangeTracking() {
   for (int id = 1; id < static_cast<int>(effect_tree.size()); ++id) {
     EffectNode* node = effect_tree.Node(id);
     EffectNode* parent_node = effect_tree.parent(node);
     effect_tree.UpdateEffectChanged(node, parent_node);
@@ skipping 363 matching lines @@
 
   const EffectNode* effect_node = effect_tree.Node(effect_id);
 
   bool success = GetFromTarget(transform_id, effect_id, transform);
   transform->Scale(effect_node->surface_contents_scale.x(),
                    effect_node->surface_contents_scale.y());
   return success;
 }
 
 }  // namespace cc