The Sky compositor should recycle textures

sky/compositor/resource_manager.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 "sky/compositor/resource_manager.h"
 
 #ifndef GL_GLEXT_PROTOTYPES
 #define GL_GLEXT_PROTOTYPES
 #endif
 
@@ skipping 13 matching lines @@
     : gl_context_(gl_context), next_resource_id_(0) {
 }
 
 ResourceManager::~ResourceManager() {
   STLDeleteContainerPairSecondPointers(resource_to_texture_map_.begin(),
                                        resource_to_texture_map_.end());
 }
 
 scoped_ptr<mojo::GLTexture> ResourceManager::CreateTexture(
     const gfx::Size& size) {
+  if (!available_textures_.empty()) {
+    scoped_ptr<mojo::GLTexture> texture(available_textures_.back());
+    available_textures_.back() = nullptr;
+    available_textures_.pop_back();
+    if (texture->size() == size)
+      return texture.Pass();
+    // Currently we only support caching textures of a constant size.
+    available_textures_.clear();
+  }
+
   gl_context_->MakeCurrent();
   return make_scoped_ptr(new mojo::GLTexture(
       gl_context_, mojo::TypeConverter<mojo::Size, gfx::Size>::Convert(size)));
 }
 
 mojo::TransferableResourcePtr ResourceManager::CreateTransferableResource(
     Layer* layer) {
   scoped_ptr<mojo::GLTexture> texture = layer->GetTexture();
   mojo::Size size = texture->size();
 
@@ skipping 31 matching lines @@
   gl_context_->MakeCurrent();
   for (size_t i = 0u; i < resources.size(); ++i) {
     mojo::ReturnedResourcePtr resource = resources[i].Pass();
     DCHECK_EQ(1, resource->count);
     auto iter = resource_to_texture_map_.find(resource->id);
     if (iter == resource_to_texture_map_.end())
       continue;
     mojo::GLTexture* texture = iter->second;
     DCHECK_NE(0u, texture->texture_id());
     resource_to_texture_map_.erase(iter);
     // TODO(abarth): Consider recycling the texture.

[jamesr, 2015/01/15 18:51:50]

this can go away now

     glWaitSyncPointCHROMIUM(resource->sync_point);
-    delete texture;
+    available_textures_.push_back(texture);
   }
 }
 
 }  // namespace examples