cc/layers/video_frame_provider_client_impl.cc

   1 // Copyright 2013 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 "cc/layers/video_frame_provider_client_impl.h"
   6
   7 #include "base/trace_event/trace_event.h"
   8 #include "cc/base/math_util.h"
   9 #include "cc/layers/video_layer_impl.h"
  10 #include "media/base/video_frame.h"
  11
  12 namespace cc {
  13
  14 // static
  15 scoped_refptr<VideoFrameProviderClientImpl>
  16 VideoFrameProviderClientImpl::Create(VideoFrameProvider* provider,
  17                                      VideoFrameControllerClient* client) {
  18   return make_scoped_refptr(new VideoFrameProviderClientImpl(provider, client));
  19 }
  20
  21 VideoFrameProviderClientImpl::VideoFrameProviderClientImpl(
  22     VideoFrameProvider* provider,
  23     VideoFrameControllerClient* client)
  24     : provider_(provider),
  25       client_(client),
  26       active_video_layer_(nullptr),
  27       stopped_(false),
  28       rendering_(false) {
  29   // This only happens during a commit on the compositor thread while the main
  30   // thread is blocked. That makes this a thread-safe call to set the video
  31   // frame provider client that does not require a lock. The same is true of
  32   // the call to Stop().
  33   provider_->SetVideoFrameProviderClient(this);
  34
  35   // This matrix is the default transformation for stream textures, and flips
  36   // on the Y axis.
  37   stream_texture_matrix_ = gfx::Transform(
  38       1.0, 0.0, 0.0, 0.0,
  39       0.0, -1.0, 0.0, 1.0,
  40       0.0, 0.0, 1.0, 0.0,
  41       0.0, 0.0, 0.0, 1.0);
  42 }
  43
  44 VideoFrameProviderClientImpl::~VideoFrameProviderClientImpl() {
  45   DCHECK(thread_checker_.CalledOnValidThread());
  46   DCHECK(stopped_);
  47 }
  48
  49 VideoLayerImpl* VideoFrameProviderClientImpl::ActiveVideoLayer() const {
  50   DCHECK(thread_checker_.CalledOnValidThread());
  51   return active_video_layer_;
  52 }
  53
  54 void VideoFrameProviderClientImpl::SetActiveVideoLayer(
  55     VideoLayerImpl* video_layer) {
  56   DCHECK(thread_checker_.CalledOnValidThread());
  57   DCHECK(video_layer);
  58   active_video_layer_ = video_layer;
  59 }
  60
  61 void VideoFrameProviderClientImpl::Stop() {
  62   DCHECK(thread_checker_.CalledOnValidThread());
  63   // It's called when the main thread is blocked, so lock isn't needed.
  64   if (provider_) {
  65     provider_->SetVideoFrameProviderClient(nullptr);
  66     provider_ = nullptr;
  67   }
  68   if (rendering_)
  69     StopRendering();
  70   active_video_layer_ = nullptr;
  71   stopped_ = true;
  72 }
  73
  74 bool VideoFrameProviderClientImpl::Stopped() const {
  75   DCHECK(thread_checker_.CalledOnValidThread());
  76   return stopped_;
  77 }
  78
  79 scoped_refptr<media::VideoFrame>
  80 VideoFrameProviderClientImpl::AcquireLockAndCurrentFrame() {
  81   DCHECK(thread_checker_.CalledOnValidThread());
  82   provider_lock_.Acquire();  // Balanced by call to ReleaseLock().
  83   if (!provider_)
  84     return nullptr;
  85
  86   return provider_->GetCurrentFrame();
  87 }
  88
  89 void VideoFrameProviderClientImpl::PutCurrentFrame() {
  90   DCHECK(thread_checker_.CalledOnValidThread());
  91   provider_lock_.AssertAcquired();
  92   provider_->PutCurrentFrame();
  93 }
  94
  95 void VideoFrameProviderClientImpl::ReleaseLock() {
  96   DCHECK(thread_checker_.CalledOnValidThread());
  97   provider_lock_.AssertAcquired();
  98   provider_lock_.Release();
  99 }
 100
 101 const gfx::Transform& VideoFrameProviderClientImpl::StreamTextureMatrix()
 102     const {
 103   DCHECK(thread_checker_.CalledOnValidThread());
 104   return stream_texture_matrix_;
 105 }
 106
 107 void VideoFrameProviderClientImpl::StopUsingProvider() {
 108   // Block the provider from shutting down until this client is done
 109   // using the frame.
 110   base::AutoLock locker(provider_lock_);
 111   provider_ = nullptr;
 112   if (rendering_)
 113     StopRendering();
 114 }
 115
 116 void VideoFrameProviderClientImpl::StartRendering() {
 117   DCHECK(thread_checker_.CalledOnValidThread());
 118   TRACE_EVENT0("cc", "VideoFrameProviderClientImpl::StartRendering");
 119   DCHECK(!rendering_);
 120   DCHECK(!stopped_);
 121   rendering_ = true;
 122   client_->AddVideoFrameController(this);
 123 }
 124
 125 void VideoFrameProviderClientImpl::StopRendering() {
 126   DCHECK(thread_checker_.CalledOnValidThread());
 127   TRACE_EVENT0("cc", "VideoFrameProviderClientImpl::StopRendering");
 128   DCHECK(rendering_);
 129   DCHECK(!stopped_);
 130   client_->RemoveVideoFrameController(this);
 131   rendering_ = false;
 132 }
 133
 134 void VideoFrameProviderClientImpl::DidReceiveFrame() {
 135   TRACE_EVENT1("cc",
 136                "VideoFrameProviderClientImpl::DidReceiveFrame",
 137                "active_video_layer",
 138                !!active_video_layer_);
 139   DCHECK(thread_checker_.CalledOnValidThread());
 140   if (active_video_layer_)
 141     active_video_layer_->SetNeedsRedraw();
 142 }
 143
 144 void VideoFrameProviderClientImpl::DidUpdateMatrix(const float* matrix) {
 145   DCHECK(thread_checker_.CalledOnValidThread());
 146   stream_texture_matrix_ = gfx::Transform(
 147       matrix[0], matrix[4], matrix[8], matrix[12],
 148       matrix[1], matrix[5], matrix[9], matrix[13],
 149       matrix[2], matrix[6], matrix[10], matrix[14],
 150       matrix[3], matrix[7], matrix[11], matrix[15]);
 151   if (active_video_layer_)
 152     active_video_layer_->SetNeedsRedraw();
 153 }
 154
 155 void VideoFrameProviderClientImpl::OnBeginFrame(const BeginFrameArgs& args) {
 156   DCHECK(thread_checker_.CalledOnValidThread());
 157   DCHECK(rendering_);
 158   DCHECK(!stopped_);
 159
 160   TRACE_EVENT0("cc", "VideoFrameProviderClientImpl::OnBeginFrame");
 161   base::AutoLock locker(provider_lock_);
 162
 163   // We use frame_time + interval here because that is the estimated time at
 164   // which a frame returned during this phase will end up being displayed.
 165   if (!provider_ ||
 166       !provider_->UpdateCurrentFrame(args.frame_time + args.interval,
 167                                      args.frame_time + 2 * args.interval)) {
 168     return;
 169   }
 170
 171   DidReceiveFrame();
 172 }
 173
 174 }  // namespace cc