cc: Add mask and replica layer ids to the effect tree

cc/trees/tree_synchronizer.cc

 // Copyright 2011 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 "cc/trees/tree_synchronizer.h"
 
 #include <stddef.h>
 
 #include <set>
 
 #include "base/logging.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/layers/layer.h"
 #include "cc/layers/layer_collections.h"
 #include "cc/layers/layer_impl.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_impl.h"
 
 namespace cc {
 
-template <typename LayerType>
-void SynchronizeTreesInternal(LayerType* layer_root, LayerTreeImpl* tree_impl) {
+template <typename LayerType, typename LayerTreeType>
+void SynchronizeTreesInternal(LayerType* layer_root,

[jaydasika, 2016/06/14 06:12:06]

I think layer_root is a redundant argument for this function. What PushLayerList
really needs is source_tree. 

[ajuma, 2016/06/14 12:45:26]

Done. This also allowed merging PushLayerList and PushLayerListInternal, since
they were really only separate so that PushLayerList could get a tree from
layer_root and pass this tree to PushLayerListInternal.

+                              LayerTreeType* source_tree,
+                              LayerTreeImpl* tree_impl,
+                              PropertyTrees* property_trees) {
   DCHECK(tree_impl);
 
   TRACE_EVENT0("cc", "TreeSynchronizer::SynchronizeTrees");
   std::unique_ptr<OwnedLayerImplList> old_layers(tree_impl->DetachLayers());
 
   OwnedLayerImplMap old_layer_map;
   for (auto& it : *old_layers)
     old_layer_map[it->id()] = std::move(it);
 
   PushLayerList(&old_layer_map, layer_root, tree_impl);
 
-  for (auto& it : old_layer_map) {
-    if (it.second) {
-      // Need to ensure that layer destruction doesn't tear down other layers
-      // linked to this LayerImpl that have been used in the new tree.
-      it.second->ClearLinksToOtherLayers();
-    }
+  for (int id : property_trees->effect_tree.mask_replica_layer_ids()) {
+    std::unique_ptr<LayerImpl> layer_impl(ReuseOrCreateLayerImpl(
+        &old_layer_map, source_tree->LayerById(id), tree_impl));
+    tree_impl->AddLayer(std::move(layer_impl));
   }
 }
 
 void TreeSynchronizer::SynchronizeTrees(Layer* layer_root,
                                         LayerTreeImpl* tree_impl) {
-  if (!layer_root)
+  if (!layer_root) {
     tree_impl->DetachLayers();
-  else
-    SynchronizeTreesInternal(layer_root, tree_impl);
+  } else {
+    SynchronizeTreesInternal(layer_root, layer_root->layer_tree_host(),
+                             tree_impl,
+                             layer_root->layer_tree_host()->property_trees());
+  }
 }
 
 void TreeSynchronizer::SynchronizeTrees(LayerImpl* layer_root,
                                         LayerTreeImpl* tree_impl) {
-  if (!layer_root)
+  if (!layer_root) {
     tree_impl->DetachLayers();
-  else
-    SynchronizeTreesInternal(layer_root, tree_impl);
+  } else {
+    SynchronizeTreesInternal(layer_root, layer_root->layer_tree_impl(),
+                             tree_impl,
+                             layer_root->layer_tree_impl()->property_trees());
+  }
 }
 
 template <typename LayerType>
 std::unique_ptr<LayerImpl> ReuseOrCreateLayerImpl(OwnedLayerImplMap* old_layers,
                                                   LayerType* layer,
                                                   LayerTreeImpl* tree_impl) {
   if (!layer)
     return nullptr;
   std::unique_ptr<LayerImpl> layer_impl = std::move((*old_layers)[layer->id()]);
   if (!layer_impl)
     layer_impl = layer->CreateLayerImpl(tree_impl);
   return layer_impl;
 }
 
-static void SynchronizeReplicaLayer(LayerImpl* layer_impl,
-                                    std::unique_ptr<LayerImpl> new_replica,
-                                    LayerTreeImpl* tree_impl) {
-  if (layer_impl->replica_layer() &&
-      layer_impl->replica_layer() == new_replica.get()) {
-    // In this case, we only need to update the ownership, as we're essentially
-    // just resetting the replica layer.
-    tree_impl->AddLayer(std::move(new_replica));
-  } else {
-    layer_impl->SetReplicaLayer(std::move(new_replica));
-  }
-}
-
-static void SynchronizeMaskLayer(LayerImpl* layer_impl,
-                                 std::unique_ptr<LayerImpl> new_mask,
-                                 LayerTreeImpl* tree_impl) {
-  if (layer_impl->mask_layer() && layer_impl->mask_layer() == new_mask.get()) {
-    // In this case, we only need to update the ownership, as we're essentially
-    // just resetting the mask layer.
-    tree_impl->AddLayer(std::move(new_mask));
-  } else {
-    layer_impl->SetMaskLayer(std::move(new_mask));
-  }
-}
-
 template <typename LayerTreeType>
 void PushLayerListInternal(OwnedLayerImplMap* old_layers,
                            LayerTreeType* host,
                            LayerTreeImpl* tree_impl) {
   tree_impl->ClearLayerList();
   for (auto* layer : *host) {
     std::unique_ptr<LayerImpl> layer_impl(
         ReuseOrCreateLayerImpl(old_layers, layer, tree_impl));
 
-    std::unique_ptr<LayerImpl> mask_layer(
-        ReuseOrCreateLayerImpl(old_layers, layer->mask_layer(), tree_impl));
-    SynchronizeMaskLayer(layer_impl.get(), std::move(mask_layer), tree_impl);
-
-    std::unique_ptr<LayerImpl> replica_layer(
-        ReuseOrCreateLayerImpl(old_layers, layer->replica_layer(), tree_impl));
-    SynchronizeReplicaLayer(layer_impl.get(), std::move(replica_layer),
-                            tree_impl);
-    if (layer->replica_layer()) {
-      std::unique_ptr<LayerImpl> replica_mask_layer(ReuseOrCreateLayerImpl(
-          old_layers, layer->replica_layer()->mask_layer(), tree_impl));
-      SynchronizeMaskLayer(layer_impl->replica_layer(),
-                           std::move(replica_mask_layer), tree_impl);
-    }
     tree_impl->AddToLayerList(layer_impl.get());
     tree_impl->AddLayer(std::move(layer_impl));
   }
 }
 
 void PushLayerList(OwnedLayerImplMap* old_layers,
                    Layer* old_root,
                    LayerTreeImpl* tree_impl) {
   PushLayerListInternal(old_layers, old_root->layer_tree_host(), tree_impl);
   tree_impl->SetRootLayerFromLayerList();
@@ skipping 23 matching lines @@
                               active_tree);
 }
 
 void TreeSynchronizer::PushLayerProperties(LayerTreeHost* host_tree,
                                            LayerTreeImpl* impl_tree) {
   PushLayerPropertiesInternal(host_tree->LayersThatShouldPushProperties(),
                               impl_tree);
 }
 
 }  // namespace cc