UI Resource Manager

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
===================================================================
--- cc/trees/layer_tree_host.cc	(revision 214760)
+++ cc/trees/layer_tree_host.cc	(working copy)
@@ -29,6 +29,7 @@
 #include "cc/layers/render_surface.h"
 #include "cc/layers/scrollbar_layer.h"
 #include "cc/resources/prioritized_resource_manager.h"
+#include "cc/resources/ui_resource_client.h"
 #include "cc/trees/layer_tree_host_client.h"
 #include "cc/trees/layer_tree_host_common.h"
 #include "cc/trees/layer_tree_host_impl.h"
@@ -59,6 +60,11 @@
 
 RendererCapabilities::~RendererCapabilities() {}
 
+UIResourceRequest::UIResourceRequest()
+    : type(UIResourceInvalidRequest), id(0), bitmap(NULL) {}
+
+UIResourceRequest::~UIResourceRequest() {}
+
 bool LayerTreeHost::AnyLayerTreeHostInstanceExists() {
   return s_num_layer_tree_instances > 0;
 }
@@ -78,7 +84,8 @@
 
 LayerTreeHost::LayerTreeHost(LayerTreeHostClient* client,
                              const LayerTreeSettings& settings)
-    : animating_(false),
+    : next_ui_resource_id_(1),
+      animating_(false),
       needs_full_tree_sync_(true),
       needs_filter_context_(false),
       client_(client),
@@ -354,6 +361,15 @@
     pending_page_scale_animation_.reset();
   }
 
+  if (!ui_resource_request_queue_.empty()) {
+    sync_tree->set_ui_resource_request_queue(ui_resource_request_queue_);
+    ui_resource_request_queue_.clear();
+    // Process any ui resource requests in the queue.  For impl-side-painting,
+    // the queue is processed in LayerTreeHostImpl::ActivatePendingTree.
+    if (!settings_.impl_side_painting)
+      sync_tree->ProcessUIResourceRequestQueue();
+  }
+
   DCHECK(!sync_tree->ViewportSizeInvalid());
 
   if (new_impl_tree_has_no_evicted_resources) {
@@ -419,6 +435,8 @@
   if (output_surface_lost_)
     return;
 
+  DidLoseUIResources();
+
   num_failed_recreate_attempts_ = 0;
   output_surface_lost_ = true;
   SetNeedsCommit();
@@ -1046,7 +1064,7 @@
 }
 
 void LayerTreeHost::SetDeviceScaleFactor(float device_scale_factor) {
-  if (device_scale_factor ==  device_scale_factor_)
+  if (device_scale_factor == device_scale_factor_)
     return;
   device_scale_factor_ = device_scale_factor;
 
@@ -1102,4 +1120,68 @@
   }
 }
 
+UIResourceId LayerTreeHost::CreateUIResource(UIResourceClient* client) {
+  DCHECK(client);
+
+  UIResourceRequest request;
+  bool resource_lost = false;
+  request.type = UIResourceCreate;
+  request.id = next_ui_resource_id_++;
+
+  DCHECK(ui_resource_client_map_.find(request.id) ==
+         ui_resource_client_map_.end());
+
+  request.bitmap = client->GetBitmap(request.id, resource_lost);
+  ui_resource_request_queue_.push_back(request);
+  ui_resource_client_map_[request.id] = client;
+  return request.id;
+}
+
+// Deletes a UI resource.  May safely be called more than once.
+void LayerTreeHost::DeleteUIResource(UIResourceId uid) {
+  UIResourceClientMap::iterator iter = ui_resource_client_map_.find(uid);
+  if (iter != ui_resource_client_map_.end()) {

[enne (OOO), 2013/07/31 22:02:40]

style nit: make this an early return rather than a large conditional block? (and
same below?)

[powei, 2013/08/01 00:05:10]

Done.

+    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 uid) {
+  UIResourceClientMap::iterator iter = ui_resource_client_map_.find(uid);
+  if (iter != ui_resource_client_map_.end()) {
+    UIResourceRequest request;
+    bool resource_lost = true;
+    request.type = UIResourceCreate;
+    request.id = uid;
+    request.bitmap = iter->second->GetBitmap(uid, resource_lost);
+    DCHECK(request.bitmap.get());
+    ui_resource_request_queue_.push_back(request);
+  }
+}
+
+void LayerTreeHost::DidLoseUIResources() {
+  typedef base::hash_set<UIResourceId> UIResourceIdSet;
+  UIResourceIdSet request_set;

[aelias_OOO_until_Jul13, 2013/07/31 21:00:30]

Is this needed anymore?  For simplicity, can we just call UIResourceLost on all
resources in the map?

[powei, 2013/07/31 21:29:39]

If a user has created a resource, but the context was lost before the creation
can be carried out on the impl-side, should we honor the original request or
make a new resource-lost request?  I don't know the use-cases well-enough to say
one way or another.  What are your thoughts?

[aelias_OOO_until_Jul13, 2013/07/31 21:56:51]

It doesn't matter much as long as we don't crash, leak, or incorrectly delete a
resource.  I think we should optimize to make the code simpler.

[powei, 2013/08/01 00:05:10]

Done.

+
+  for (UIResourceRequestQueue::iterator iter =
+           ui_resource_request_queue_.begin();
+       iter != ui_resource_request_queue_.end();
+       ++iter) {
+    request_set.insert(iter->id);
+  }
+
+  // When output surface is lost, we need to recreate the resource.
+  for (UIResourceClientMap::iterator iter = ui_resource_client_map_.begin();
+       iter != ui_resource_client_map_.end();
+       ++iter) {
+    // If the resource was to be created/deleted, then the original request will
+    // be honored instead of treating it as resource lost.
+    if (request_set.find(iter->first) == request_set.end())
+      UIResourceLost(iter->first);
+  }
+}
+
 }  // namespace cc