Display Compositor: Allocate LocalFrameId in client.

ui/aura/mus/window_compositor_frame_sink.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 "ui/aura/mus/window_compositor_frame_sink.h"
 
 #include "base/bind.h"
 #include "cc/output/compositor_frame_sink_client.h"
 #include "gpu/ipc/client/gpu_channel_host.h"
 
@@ skipping 46 matching lines @@
   compositor_frame_sink_.reset();
   cc::CompositorFrameSink::DetachFromClient();
 }
 
 void WindowCompositorFrameSink::SubmitCompositorFrame(
     cc::CompositorFrame frame) {
   DCHECK(thread_checker_);
   DCHECK(thread_checker_->CalledOnValidThread());
   if (!compositor_frame_sink_)
     return;
-  compositor_frame_sink_->SubmitCompositorFrame(std::move(frame));
+
+  gfx::Size frame_size;
+  if (!frame.render_pass_list.empty())

[sadrul, 2016/11/22 19:22:25]

Is it valid for a frame to have no render-pass? (applies to all the rest of the
places this is checked)

[Fady Samuel, 2016/11/22 19:24:38]

The pattern of submitting an empty CompositorFrame is used in some places to
evict resources used by the previous frame.

[sadrul, 2016/11/22 19:25:48]

I see. Should that reset the frame/frame-sink size and id?

+    frame_size = frame.render_pass_list[0]->output_rect.size();
+  if (!local_frame_id_.is_valid() || frame_size != last_submitted_frame_size_)
+    local_frame_id_ = id_allocator_.GenerateId();
+
+  compositor_frame_sink_->SubmitCompositorFrame(local_frame_id_,
+                                                std::move(frame));
+
+  last_submitted_frame_size_ = frame_size;
 }
 
 WindowCompositorFrameSink::WindowCompositorFrameSink(
     scoped_refptr<cc::ContextProvider> context_provider,
     gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
-    mojo::InterfacePtrInfo<cc::mojom::MojoCompositorFrameSink>
-        compositor_frame_sink_info,
+    cc::mojom::MojoCompositorFrameSinkPtrInfo compositor_frame_sink_info,
     cc::mojom::MojoCompositorFrameSinkClientRequest client_request)
     : cc::CompositorFrameSink(std::move(context_provider),
                               nullptr,
                               gpu_memory_buffer_manager,
                               nullptr),
       compositor_frame_sink_info_(std::move(compositor_frame_sink_info)),
       client_request_(std::move(client_request)) {}
 
 void WindowCompositorFrameSink::DidReceiveCompositorFrameAck() {
   DCHECK(thread_checker_);
@@ skipping 24 matching lines @@
 WindowCompositorFrameSinkBinding::~WindowCompositorFrameSinkBinding() {}
 
 WindowCompositorFrameSinkBinding::WindowCompositorFrameSinkBinding(
     cc::mojom::MojoCompositorFrameSinkRequest compositor_frame_sink_request,
     mojo::InterfacePtrInfo<cc::mojom::MojoCompositorFrameSinkClient>
         compositor_frame_sink_client)
     : compositor_frame_sink_request_(std::move(compositor_frame_sink_request)),
       compositor_frame_sink_client_(std::move(compositor_frame_sink_client)) {}
 
 }  // namespace aura