UI Resource Manager

cc/trees/layer_tree_host.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/layer_tree_host.h"
 
 #include <algorithm>
 #include <stack>
 
 #include "base/bind.h"
@@ skipping 55 matching lines @@
     scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner) {
   scoped_ptr<LayerTreeHost> layer_tree_host(new LayerTreeHost(client,
                                                               settings));
   if (!layer_tree_host->Initialize(impl_task_runner))
     return scoped_ptr<LayerTreeHost>();
   return layer_tree_host.Pass();
 }
 
 LayerTreeHost::LayerTreeHost(LayerTreeHostClient* client,
                              const LayerTreeSettings& settings)
-    : animating_(false),
+    : ui_resource_id_(1),
+      animating_(false),
       needs_full_tree_sync_(true),
       needs_filter_context_(false),
       client_(client),
       commit_number_(0),
       rendering_stats_instrumentation_(RenderingStatsInstrumentation::Create()),
       output_surface_can_be_initialized_(true),
       output_surface_lost_(true),
       num_failed_recreate_attempts_(0),
       settings_(settings),
       debug_state_(settings.initial_debug_state),
@@ skipping 154 matching lines @@
   TRACE_EVENT0("cc", "LayerTreeHost::CommitTo");
 }
 
 // This function commits the LayerTreeHost to an impl tree. When modifying
 // this function, keep in mind that the function *runs* on the impl thread! Any
 // code that is logically a main thread operation, e.g. deletion of a Layer,
 // should be delayed until the LayerTreeHost::CommitComplete, which will run
 // after the commit, but on the main thread.
 void LayerTreeHost::FinishCommitOnImplThread(LayerTreeHostImpl* host_impl) {
   DCHECK(proxy_->IsImplThread());
-
   // If there are linked evicted backings, these backings' resources may be put
   // into the impl tree, so we can't draw yet. Determine this before clearing
   // all evicted backings.
   bool new_impl_tree_has_no_evicted_resources = false;
   if (contents_texture_manager_) {
     new_impl_tree_has_no_evicted_resources =
         !contents_texture_manager_->LinkedEvictedBackingsExist();
 
     // If the memory limit has been increased since this now-finishing
     // commit began, and the extra now-available memory would have been used,
@@ skipping 80 matching lines @@
   if (pending_page_scale_animation_) {
     host_impl->StartPageScaleAnimation(
         pending_page_scale_animation_->target_offset,
         pending_page_scale_animation_->use_anchor,
         pending_page_scale_animation_->scale,
         base::TimeTicks::Now(),
         pending_page_scale_animation_->duration);
     pending_page_scale_animation_.reset();
   }
 
+  if (!ui_resource_request_queue_.empty()) {
+    if (settings_.impl_side_painting) {
+      host_impl->set_ui_resource_request_queue(ui_resource_request_queue_);
+      ui_resource_request_queue_.clear();
+    } else {
+      while (ui_resource_request_queue_.size() > 0) {

[enne (OOO), 2013/07/22 23:09:15]

Can you share this commit-time queue-processing functionality with the one
during activation?

[powei, 2013/07/24 02:28:29]

Done.

+        UIResourceRequest req = ui_resource_request_queue_.front();
+        ui_resource_request_queue_.pop_front();
+        switch (req.type) {
+          case UIResourceCreate:
+            host_impl->CreateUIResource(req.id, req.bitmap);
+            break;
+          case UIResourceDelete:
+            host_impl->DeleteUIResource(req.id);
+            break;
+        }
+      }
+    }
+  }
+
   DCHECK(!sync_tree->ViewportSizeInvalid());
 
   if (new_impl_tree_has_no_evicted_resources) {
     if (sync_tree->ContentsTexturesPurged())
       sync_tree->ResetContentsTexturesPurged();
   }
 
   if (!settings_.impl_side_painting) {
     // If we're not in impl-side painting, the tree is immediately
     // considered active.
@@ skipping 686 matching lines @@
     (*iter).second->Animate(monotonic_time);
     bool start_ready_animations = true;
     (*iter).second->UpdateState(start_ready_animations, NULL);
   }
 }
 
 skia::RefPtr<SkPicture> LayerTreeHost::CapturePicture() {
   return proxy_->CapturePicture();
 }
 
+
+UIResourceId
+LayerTreeHost::CreateUIResource(const UIResourceCallback& bitmap_cb) {
+  UIResourceRequest request;
+  request.type = UIResourceCreate;
+  request.id = ui_resource_id_++;
+  // The boolean parameter indicates this retrieval is not due to a

[enne (OOO), 2013/07/22 23:09:15]

style nit: Rather than a comment, just say "bool resource_lost = false" and pass
that to bitmap-cb.Run().

[powei, 2013/07/24 02:28:29]

Done.

+  // resource lost.
+  request.bitmap = bitmap_cb.Run(false);
+  ui_resource_request_queue_.push_back(request);
+  ui_resource_client_map_[request.id] = bitmap_cb;

[enne (OOO), 2013/07/22 23:09:15]

Can you DCHECK that this doesn't exist in the map yet?

[powei, 2013/07/24 02:28:29]

Done.

+  return request.id;
+}
+
+// Deletes a UI resource.  May safely be called more than once.
+void LayerTreeHost::DeleteUIResource(UIResourceId uid) {
+  if (ui_resource_client_map_.find(uid) != ui_resource_client_map_.end()) {
+    UIResourceRequest request;
+    request.type = UIResourceDelete;
+    request.id = uid;
+    ui_resource_request_queue_.push_back(request);
+    ui_resource_client_map_.erase(uid);
+  }
+}
+
+void LayerTreeHost::UIResourceLost(UIResourceId id) {
+  UIResourceClientMap::iterator iter = ui_resource_client_map_.find(id);
+  if (iter != ui_resource_client_map_.end()) {
+    UIResourceRequest request;
+    request.type = UIResourceCreate;
+    request.id = id;
+    request.bitmap = iter->second.Run(true);

[aelias_OOO_until_Jul13, 2013/07/23 00:06:48]

I think that if this callback is a destroyed weak_ptr, you will probably get a
return value of NULL.  You should do something appropriate in that circumstance
(I guess create a 1x1 white resource).  Please also add a unit test for this
case.

[powei, 2013/07/24 02:28:29]

I don't know if a weak_ptr can be passed with the callback.  See comment in
scrollbar_layer.cc.

+    ui_resource_request_queue_.push_back(request);
+  }
+}
+
+
 }  // namespace cc