sync compositor: Add output_surface_id

content/browser/android/synchronous_compositor_host.cc

 // Copyright 2015 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 "content/browser/android/synchronous_compositor_host.h"
 
 #include <utility>
 
 #include "base/containers/hash_tables.h"
 #include "base/memory/shared_memory.h"
@@ skipping 22 matching lines @@
     bool use_in_proc_software_draw)
     : rwhva_(rwhva),
       client_(client),
       ui_task_runner_(
           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI)),
       routing_id_(rwhva_->GetRenderWidgetHost()->GetRoutingID()),
       sender_(rwhva_->GetRenderWidgetHost()),
       use_in_process_zero_copy_software_draw_(use_in_proc_software_draw),
       is_active_(false),
       bytes_limit_(0u),
+      current_output_surface_id_(0u),

[hush (inactive), 2016/03/08 23:55:49]

Not sure where we get the correct value of current_output_surface_id_. Is 0 a
guaranteed invalid id?
Also it is only set during ReturnResources. And we keep using 0u as surface id
in PopulateCommonParams until resources are returned?

We should assign the current_output_surface_id_ during DrawHW at least.

[boliu, 2016/03/09 00:29:59]

Yes
Yeah. The resource list is guaranteed to be empty before the first
ReturnResources. So having an invalid output surface id doesn't really matter.
no! the output_surface_id should refers to the resources that are in the
returned resource array, not what's in the current/new frame

hmm, maybe I should rename this var or add a comment

[hush (inactive), 2016/03/09 02:36:17]

yeah. Renaming the variable name to indicate this would be good.

       root_scroll_offset_updated_by_browser_(false),
       renderer_param_version_(0u),
       need_animate_scroll_(false),
       need_invalidate_count_(0u),
       need_begin_frame_(false),
       did_activate_pending_tree_count_(0u),
       weak_ptr_factory_(this) {
   client_->DidInitializeCompositor(this);
 }
 
@@ skipping 10 matching lines @@
     IPC_MESSAGE_HANDLER(SyncCompositorHostMsg_OverScroll, OnOverScroll)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void SynchronousCompositorHost::DidBecomeCurrent() {
   client_->DidBecomeCurrent(this);
 }
 
-scoped_ptr<cc::CompositorFrame> SynchronousCompositorHost::DemandDrawHw(
+SynchronousCompositor::Frame SynchronousCompositorHost::DemandDrawHw(
     const gfx::Size& surface_size,
     const gfx::Transform& transform,
     const gfx::Rect& viewport,
     const gfx::Rect& clip,
     const gfx::Rect& viewport_rect_for_tile_priority,
     const gfx::Transform& transform_for_tile_priority) {
   SyncCompositorDemandDrawHwParams params(surface_size, transform, viewport,
                                           clip, viewport_rect_for_tile_priority,
                                           transform_for_tile_priority);
-  scoped_ptr<cc::CompositorFrame> frame(new cc::CompositorFrame);
+  SynchronousCompositor::Frame frame;
+  frame.frame.reset(new cc::CompositorFrame);
   SyncCompositorCommonBrowserParams common_browser_params;
   PopulateCommonParams(&common_browser_params);
   SyncCompositorCommonRendererParams common_renderer_params;
   if (!sender_->Send(new SyncCompositorMsg_DemandDrawHw(
           routing_id_, common_browser_params, params, &common_renderer_params,
-          frame.get()))) {
-    return nullptr;
+          &frame.output_surface_id, frame.frame.get()))) {
+    return SynchronousCompositor::Frame();
   }
   ProcessCommonParams(common_renderer_params);
-  if (!frame->delegated_frame_data) {
+  if (!frame.frame->delegated_frame_data) {
     // This can happen if compositor did not swap in this draw.
-    frame.reset();
+    frame.frame.reset();
   }
-  if (frame)
-    UpdateFrameMetaData(frame->metadata);
+  if (frame.frame)
+    UpdateFrameMetaData(frame.frame->metadata);
   return frame;
 }
 
 void SynchronousCompositorHost::UpdateFrameMetaData(
     const cc::CompositorFrameMetadata& frame_metadata) {
   rwhva_->SynchronousFrameMetadata(frame_metadata);
 }
 
 namespace {
 
@@ skipping 151 matching lines @@
   software_draw_shm_ = std::move(software_draw_shm);
   ProcessCommonParams(common_renderer_params);
 }
 
 void SynchronousCompositorHost::SendZeroMemory() {
   // No need to check return value.
   sender_->Send(new SyncCompositorMsg_ZeroSharedMemory(routing_id_));
 }
 
 void SynchronousCompositorHost::ReturnResources(
+    uint32_t output_surface_id,
     const cc::CompositorFrameAck& frame_ack) {
+  if (current_output_surface_id_ != output_surface_id) {
+    returned_resources_.clear();
+    current_output_surface_id_ = output_surface_id;
+  }
   returned_resources_.insert(returned_resources_.end(),
                              frame_ack.resources.begin(),
                              frame_ack.resources.end());
 }
 
 void SynchronousCompositorHost::SetMemoryPolicy(size_t bytes_limit) {
   if (bytes_limit_ == bytes_limit)
     return;
   size_t current_bytes_limit = bytes_limit_;
   bytes_limit_ = bytes_limit;
@@ skipping 92 matching lines @@
   client_->DidOverscroll(over_scroll_params.accumulated_overscroll,
                          over_scroll_params.latest_overscroll_delta,
                          over_scroll_params.current_fling_velocity);
 }
 
 void SynchronousCompositorHost::PopulateCommonParams(
     SyncCompositorCommonBrowserParams* params) {
   DCHECK(params);
   DCHECK(params->ack.resources.empty());
   params->bytes_limit = bytes_limit_;
+  params->output_surface_id = current_output_surface_id_;
   params->ack.resources.swap(returned_resources_);
   if (root_scroll_offset_updated_by_browser_) {
     params->root_scroll_offset = root_scroll_offset_;
     params->update_root_scroll_offset = root_scroll_offset_updated_by_browser_;
     root_scroll_offset_updated_by_browser_ = false;
   }
   params->begin_frame_source_paused = !is_active_;
 
   weak_ptr_factory_.InvalidateWeakPtrs();
 }
@@ skipping 34 matching lines @@
         params.scrollable_size, params.page_scale_factor,
         params.min_page_scale_factor, params.max_page_scale_factor);
   }
 }
 
 void SynchronousCompositorHost::UpdateNeedsBeginFrames() {
   rwhva_->OnSetNeedsBeginFrames(is_active_ && need_begin_frame_);
 }
 
 }  // namespace content