Allow CopyOutputRequests on all render passes of a surface

cc/surfaces/surface_aggregator.cc

Index: cc/surfaces/surface_aggregator.cc
diff --git a/cc/surfaces/surface_aggregator.cc b/cc/surfaces/surface_aggregator.cc
index 620ada738264db8151307cfce4269c90a2352d05..88f320d5d3d499dba82618e222df4344c5736c70 100644
--- a/cc/surfaces/surface_aggregator.cc
+++ b/cc/surfaces/surface_aggregator.cc
@@ -21,6 +21,22 @@
 #include "cc/trees/blocking_task_runner.h"
 
 namespace cc {
+namespace {
+
+void MoveMatchingRequests(
+    RenderPassId id,
+    std::multimap<RenderPassId, CopyOutputRequest*>* copy_requests,
+    ScopedPtrVector<CopyOutputRequest>* output_requests) {
+  auto request_range = copy_requests->equal_range(id);
+  for (auto it = request_range.first; it != request_range.second; ++it) {
+    DCHECK(it->second);
+    output_requests->push_back(scoped_ptr<CopyOutputRequest>(it->second));
+    it->second = nullptr;
+  }
+  copy_requests->erase(request_range.first, request_range.second);
+}
+
+}  // namespace
 
 SurfaceAggregator::SurfaceAggregator(SurfaceManager* manager,
                                      ResourceProvider* provider)
@@ -165,16 +181,21 @@ void SurfaceAggregator::HandleSurfaceQuad(const SurfaceDrawQuad* surface_quad,
   if (!frame_data)
     return;
 
+  std::multimap<RenderPassId, CopyOutputRequest*> copy_requests;
+  surface->TakeCopyOutputRequests(&copy_requests);
+
   RenderPassList render_pass_list;
   bool invalid_frame = TakeResources(surface, frame_data, &render_pass_list);
-  if (invalid_frame)
+  if (invalid_frame) {
+    for (auto& request : copy_requests) {
+      request.second->SendEmptyResult();
+      delete request.second;
+    }
     return;
+  }
 
   SurfaceSet::iterator it = referenced_surfaces_.insert(surface_id).first;
 
-  ScopedPtrVector<CopyOutputRequest> copy_requests;
-  surface->TakeCopyOutputRequests(&copy_requests);
-
   bool merge_pass = copy_requests.empty();
 
   const RenderPassList& referenced_passes = render_pass_list;
@@ -195,6 +216,8 @@ void SurfaceAggregator::HandleSurfaceQuad(const SurfaceDrawQuad* surface_quad,
                       source.transform_to_root_target,
                       source.has_transparent_background);
 
+    MoveMatchingRequests(source.id, &copy_requests, &copy_pass->copy_requests);

[jamesr, 2014/10/15 23:51:24]

the RenderPassIds in copy_requests will be in the surface's ID namespace, right?
 Don't we have to map them into the aggregated namespace (i.e. call RemapPassId)
in order for them to refer to aggregated pass IDs?

+
     // Contributing passes aggregated in to the pass list need to take the
     // transform of the surface quad into account to update their transform to
     // the root surface.
@@ -226,8 +249,6 @@ void SurfaceAggregator::HandleSurfaceQuad(const SurfaceDrawQuad* surface_quad,
   } else {
     RenderPassId remapped_pass_id = RemapPassId(last_pass.id, surface_id);
 
-    dest_pass_list_->back()->copy_requests.swap(copy_requests);
-
     SharedQuadState* shared_quad_state =
         dest_pass->CreateAndAppendSharedQuadState();
     shared_quad_state->CopyFrom(surface_quad->shared_quad_state);
@@ -319,8 +340,18 @@ void SurfaceAggregator::CopyQuadsToPass(
   }
 }
 
-void SurfaceAggregator::CopyPasses(const RenderPassList& source_pass_list,
-                                   const Surface* surface) {
+void SurfaceAggregator::CopyPasses(const DelegatedFrameData* frame_data,
+                                   Surface* surface) {
+  RenderPassList source_pass_list;
+
+  // The root surface is allowed to have copy output requests, so grab them
+  // off its render passes.
+  std::multimap<RenderPassId, CopyOutputRequest*> copy_requests;
+  surface->TakeCopyOutputRequests(&copy_requests);
+
+  bool invalid_frame = TakeResources(surface, frame_data, &source_pass_list);
+  DCHECK(!invalid_frame);
+
   for (size_t i = 0; i < source_pass_list.size(); ++i) {
     const RenderPass& source = *source_pass_list[i];
 
@@ -328,6 +359,8 @@ void SurfaceAggregator::CopyPasses(const RenderPassList& source_pass_list,
     size_t dq_size = source.quad_list.size();
     scoped_ptr<RenderPass> copy_pass(RenderPass::Create(sqs_size, dq_size));
 
+    MoveMatchingRequests(source.id, &copy_requests, &copy_pass->copy_requests);
+
     RenderPassId remapped_pass_id =
         RemapPassId(source.id, surface->surface_id());
 
@@ -361,20 +394,12 @@ scoped_ptr<CompositorFrame> SurfaceAggregator::Aggregate(SurfaceId surface_id) {
 
   DCHECK(root_surface_frame->delegated_frame_data);
 
-  RenderPassList source_pass_list;
-
   SurfaceSet::iterator it = referenced_surfaces_.insert(surface_id).first;
 
   dest_resource_list_ = &frame->delegated_frame_data->resource_list;
   dest_pass_list_ = &frame->delegated_frame_data->render_pass_list;
 
-  bool invalid_frame =
-      TakeResources(surface,
-                    root_surface_frame->delegated_frame_data.get(),
-                    &source_pass_list);
-  DCHECK(!invalid_frame);
-
-  CopyPasses(source_pass_list, surface);
+  CopyPasses(root_surface_frame->delegated_frame_data.get(), surface);
 
   referenced_surfaces_.erase(it);
   DCHECK(referenced_surfaces_.empty());