cc: Implement unified BeginFrame on aura

ui/compositor/compositor.cc

 // Copyright (c) 2012 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/compositor/compositor.h"
 
 #include <algorithm>
 #include <deque>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
 #include "base/sys_info.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/base/latency_info_swap_promise.h"
 #include "cc/base/switches.h"
 #include "cc/input/input_handler.h"
 #include "cc/layers/layer.h"
 #include "cc/output/begin_frame_args.h"
 #include "cc/output/context_provider.h"
 #include "cc/scheduler/begin_frame_source.h"
 #include "cc/surfaces/surface_id_allocator.h"
 #include "cc/trees/layer_tree_host.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/compositor_switches.h"
-#include "ui/compositor/compositor_vsync_manager.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animator_collection.h"
 #include "ui/gfx/frame_time.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_switches.h"
 
 namespace {
 
 const double kDefaultRefreshRate = 60.0;
@@ skipping 25 matching lines @@
 }
 
 Compositor::Compositor(gfx::AcceleratedWidget widget,
                        ui::ContextFactory* context_factory,
                        scoped_refptr<base::SingleThreadTaskRunner> task_runner)
     : context_factory_(context_factory),
       root_layer_(NULL),
       widget_(widget),
       surface_id_allocator_(context_factory->CreateSurfaceIdAllocator()),
       task_runner_(task_runner),
-      vsync_manager_(new CompositorVSyncManager()),
       device_scale_factor_(0.0f),
       last_started_frame_(0),
       last_ended_frame_(0),
       disable_schedule_composite_(false),
       compositor_lock_(NULL),
       layer_animator_collection_(this),
       weak_ptr_factory_(this) {
   root_web_layer_ = cc::Layer::Create();
 
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
 
   cc::LayerTreeSettings settings;
   // When impl-side painting is enabled, this will ensure PictureLayers always
   // can have LCD text, to match the previous behaviour with ContentLayers,
   // where LCD-not-allowed notifications were ignored.
   settings.layers_always_allowed_lcd_text = true;
   settings.renderer_settings.refresh_rate =
       context_factory_->DoesCreateTestContexts() ? kTestRefreshRate
                                                  : kDefaultRefreshRate;
   settings.main_frame_before_activation_enabled = false;
   settings.throttle_frame_production =
       !command_line->HasSwitch(switches::kDisableGpuVsync);
+#if defined(USE_AURA)
+  settings.forward_begin_frames_to_children = true;

[brianderson, 2015/03/02 22:38:16]

This flag doesn't seem useful like we thought it would be. Just get rid of it?

Followup patch is fine, but please open a new issue.

[simonhong, 2015/03/03 22:54:12]

Yep, setting state_machine.SetChildrenNeedBeginFrames() is sufficient.
Removed.

+#endif
 #if !defined(OS_MACOSX)
   settings.renderer_settings.partial_swap_enabled =
       !command_line->HasSwitch(cc::switches::kUIDisablePartialSwap);
 #endif
 #if defined(OS_CHROMEOS)
   settings.per_tile_painting_enabled = true;
 #endif
 #if defined(OS_WIN)
   settings.disable_hi_res_timer_tasks_on_battery =
       !context_factory_->DoesCreateTestContexts();
@@ skipping 38 matching lines @@
 
 Compositor::~Compositor() {
   TRACE_EVENT0("shutdown", "Compositor::destructor");
 
   CancelCompositorLock();
   DCHECK(!compositor_lock_);
 
   FOR_EACH_OBSERVER(CompositorObserver, observer_list_,
                     OnCompositingShuttingDown(this));
 
+  DCHECK(!begin_frame_observer_list_.might_have_observers());
+
   if (root_layer_)
     root_layer_->SetCompositor(NULL);
 
   // Stop all outstanding draws before telling the ContextFactory to tear
   // down any contexts that the |host_| may rely upon.
   host_.reset();
 
   context_factory_->RemoveCompositor(this);
 }
 
@@ skipping 76 matching lines @@
 }
 
 void Compositor::SetVisible(bool visible) {
   host_->SetVisible(visible);
 }
 
 bool Compositor::IsVisible() {
   return host_->visible();
 }
 
-scoped_refptr<CompositorVSyncManager> Compositor::vsync_manager() const {
-  return vsync_manager_;
+void Compositor::SetAuthoritativeVSyncInterval(
+    const base::TimeDelta& interval) {
+  host_->SetAuthoritativeVSyncInterval(interval);
 }
 
 void Compositor::AddObserver(CompositorObserver* observer) {
   observer_list_.AddObserver(observer);
 }
 
 void Compositor::RemoveObserver(CompositorObserver* observer) {
   observer_list_.RemoveObserver(observer);
 }
 
 bool Compositor::HasObserver(const CompositorObserver* observer) const {
   return observer_list_.HasObserver(observer);
 }
 
 void Compositor::AddAnimationObserver(CompositorAnimationObserver* observer) {
   animation_observer_list_.AddObserver(observer);
   host_->SetNeedsAnimate();
 }
 
 void Compositor::RemoveAnimationObserver(
     CompositorAnimationObserver* observer) {
   animation_observer_list_.RemoveObserver(observer);
 }
 
 bool Compositor::HasAnimationObserver(
     const CompositorAnimationObserver* observer) const {
   return animation_observer_list_.HasObserver(observer);
 }
 
+void Compositor::AddBeginFrameObserver(

[brianderson, 2015/03/02 22:38:17]

Please add unit tests for this since the last_begin_frame_args_sent_to_observer
logic is hard to get right.

+    CompositorBeginFrameObserver* observer,
+    const cc::BeginFrameArgs& last_begin_frame_args_sent_to_observer) {
+  // If |last_begin_frame_args_| is still effective, send it to the new
+  // |observer| immediately.
+  if (!last_begin_frame_args_sent_to_observer.deadline.is_null() &&

[brianderson, 2015/03/02 22:38:16]

Is this check for a null deadline necessary?

[simonhong, 2015/03/03 22:54:12]

I also can't remember why I added this a while ago. ;)
Removed.

+      last_begin_frame_args_sent_to_observer != missed_begin_frame_args_) {

[brianderson, 2015/03/02 22:38:16]

It is possible that last_begin_frame_args_sent_to_observer.type and 
missed_begin_frame_args_.type are not equal even though they are otherwise
equal.

Can you compare the frame_time's instead so that the type doesn't mess us up?

[simonhong, 2015/03/03 22:54:12]

Done.

+    missed_begin_frame_args_.type = cc::BeginFrameArgs::MISSED;

[brianderson, 2015/03/02 22:38:17]

Can you move this line to the end of Compositor::SendBeginFramesToChildren?

[simonhong, 2015/03/03 22:54:12]

Done.

+    observer->OnSendBeginFrame(missed_begin_frame_args_);
+  }
+
+  if (!begin_frame_observer_list_.might_have_observers())
+    SetChildrenNeedBeginFrames(true);
+  begin_frame_observer_list_.AddObserver(observer);
+}
+
+void Compositor::RemoveBeginFrameObserver(
+    CompositorBeginFrameObserver* observer) {
+  DCHECK(begin_frame_observer_list_.HasObserver(observer));
+  begin_frame_observer_list_.RemoveObserver(observer);
+
+  if (!begin_frame_observer_list_.might_have_observers())
+    SetChildrenNeedBeginFrames(false);
+}
+
 void Compositor::BeginMainFrame(const cc::BeginFrameArgs& args) {
   FOR_EACH_OBSERVER(CompositorAnimationObserver,
                     animation_observer_list_,
                     OnAnimationStep(args.frame_time));
   if (animation_observer_list_.might_have_observers())
     host_->SetNeedsAnimate();
 }
 
 void Compositor::BeginMainFrameNotExpectedSoon() {
 }
@@ skipping 40 matching lines @@
   FOR_EACH_OBSERVER(CompositorObserver, observer_list_,
                     OnCompositingStarted(this, start_time));
 }
 
 void Compositor::DidAbortSwapBuffers() {
   FOR_EACH_OBSERVER(CompositorObserver,
                     observer_list_,
                     OnCompositingAborted(this));
 }
 
+void Compositor::SendBeginFramesToChildren(const cc::BeginFrameArgs& args) {
+  FOR_EACH_OBSERVER(CompositorBeginFrameObserver,
+                    begin_frame_observer_list_,
+                    OnSendBeginFrame(args));
+  missed_begin_frame_args_ = args;
+}
+
 const cc::LayerTreeDebugState& Compositor::GetLayerTreeDebugState() const {
   return host_->debug_state();
 }
 
 void Compositor::SetLayerTreeDebugState(
     const cc::LayerTreeDebugState& debug_state) {
   host_->SetDebugState(debug_state);
 }
 
 const cc::RendererSettings& Compositor::GetRendererSettings() const {
@@ skipping 18 matching lines @@
   FOR_EACH_OBSERVER(CompositorObserver,
                     observer_list_,
                     OnCompositingLockStateChanged(this));
 }
 
 void Compositor::CancelCompositorLock() {
   if (compositor_lock_)
     compositor_lock_->CancelLock();
 }
 
+void Compositor::SetChildrenNeedBeginFrames(bool need_begin_frames) {
+  host_->SetChildrenNeedBeginFrames(need_begin_frames);
+}
+
 }  // namespace ui