UI Resource Manager

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
===================================================================
--- cc/trees/layer_tree_host.cc	(revision 210393)
+++ cc/trees/layer_tree_host.cc	(working copy)
@@ -73,7 +73,8 @@
 
 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),
@@ -248,7 +249,6 @@
 // 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.
@@ -349,6 +349,26 @@
     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) {
@@ -1055,4 +1075,41 @@
   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