content/browser/renderer_host/begin_frame_observer_proxy.cc

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/renderer_host/begin_frame_observer_proxy.h"
   6
   7 namespace content {
   8
   9 BeginFrameObserverProxy::BeginFrameObserverProxy(
  10     BeginFrameObserverProxyClient* client)
  11     : needs_begin_frames_(false),
  12       client_(client),
  13       compositor_(nullptr) {
  14 }
  15
  16 BeginFrameObserverProxy::~BeginFrameObserverProxy() {
  17 }
  18
  19 void BeginFrameObserverProxy::SetNeedsBeginFrames(bool needs_begin_frames) {
  20   if (needs_begin_frames_ == needs_begin_frames)
  21     return;
  22
  23   needs_begin_frames_ = needs_begin_frames;
  24
  25   // In some cases, BeginFrame message is requested before |client_|'s window is
  26   // added in the root window hierarchy.
  27   if (!compositor_)
  28     return;
  29
  30   if (needs_begin_frames)
  31     StartObservingBeginFrames();
  32   else
  33     StopObservingBeginFrames();
  34 }
  35
  36 void BeginFrameObserverProxy::SetCompositor(ui::Compositor* compositor) {
  37   DCHECK(!compositor_);
  38   DCHECK(compositor);
  39
  40   compositor_ = compositor;
  41   if (needs_begin_frames_)
  42     StartObservingBeginFrames();
  43 }
  44
  45 void BeginFrameObserverProxy::ResetCompositor() {
  46   if (!compositor_)
  47     return;
  48
  49   if (needs_begin_frames_)
  50     StopObservingBeginFrames();
  51   compositor_ = nullptr;
  52 }
  53
  54 void BeginFrameObserverProxy::OnSendBeginFrame(const cc::BeginFrameArgs& args) {
  55   if (last_sent_begin_frame_args_.frame_time != args.frame_time)
  56     client_->SendBeginFrame(args);
  57   last_sent_begin_frame_args_ = args;
  58 }
  59
  60 void BeginFrameObserverProxy::StartObservingBeginFrames() {
  61   DCHECK(compositor_);
  62   compositor_->AddBeginFrameObserver(this);
  63 }
  64
  65 void BeginFrameObserverProxy::StopObservingBeginFrames() {
  66   DCHECK(compositor_);
  67   compositor_->RemoveBeginFrameObserver(this);
  68 }
  69
  70 }  // namespace content