Simplify FrameConsumer interface. Remove FrameProducer interface.

remoting/client/plugin/pepper_video_renderer_2d.cc

Index: remoting/client/plugin/pepper_video_renderer_2d.cc
diff --git a/remoting/client/plugin/pepper_video_renderer_2d.cc b/remoting/client/plugin/pepper_video_renderer_2d.cc
index feca26b2e95095a66239b7c97ebcabd818e68379..5d07277e7f751338e2b917bf2c76a1a325daf919 100644
--- a/remoting/client/plugin/pepper_video_renderer_2d.cc
+++ b/remoting/client/plugin/pepper_video_renderer_2d.cc
@@ -4,12 +4,10 @@
 
 #include "remoting/client/plugin/pepper_video_renderer_2d.h"
 
-#include <functional>
-
 #include "base/bind.h"
+#include "base/callback_helpers.h"
 #include "base/strings/string_util.h"
-#include "base/synchronization/waitable_event.h"
-#include "base/time/time.h"
+#include "base/task_runner_util.h"
 #include "ppapi/cpp/completion_callback.h"
 #include "ppapi/cpp/image_data.h"
 #include "ppapi/cpp/instance.h"
@@ -19,19 +17,26 @@
 #include "remoting/base/util.h"
 #include "remoting/client/chromoting_stats.h"
 #include "remoting/client/client_context.h"
-#include "remoting/client/frame_consumer_proxy.h"
-#include "remoting/client/frame_producer.h"
 #include "remoting/client/software_video_renderer.h"
 #include "remoting/proto/video.pb.h"
+#include "third_party/libyuv/include/libyuv/scale_argb.h"
 #include "third_party/webrtc/modules/desktop_capture/desktop_frame.h"
 
+namespace remoting {
+
 namespace {
 
 // DesktopFrame that wraps a supplied pp::ImageData
 class PepperDesktopFrame : public webrtc::DesktopFrame {
  public:
   // Wraps the supplied ImageData.
-  explicit PepperDesktopFrame(const pp::ImageData& buffer);
+  explicit PepperDesktopFrame(const pp::ImageData& buffer)
+      : DesktopFrame(
+            webrtc::DesktopSize(buffer.size().width(), buffer.size().height()),
+            buffer.stride(),
+            reinterpret_cast<uint8_t*>(buffer.data()),
+            nullptr),
+        buffer_(buffer) {}
 
   // Access to underlying pepper representation.
   const pp::ImageData& buffer() const {
@@ -42,57 +47,18 @@ class PepperDesktopFrame : public webrtc::DesktopFrame {
   pp::ImageData buffer_;
 };
 
-PepperDesktopFrame::PepperDesktopFrame(const pp::ImageData& buffer)
-  : DesktopFrame(webrtc::DesktopSize(buffer.size().width(),
-                                     buffer.size().height()),
-                 buffer.stride(),
-                 reinterpret_cast<uint8_t*>(buffer.data()),
-                 nullptr),
-    buffer_(buffer) {}
-
-}  // namespace
-
-namespace remoting {
-
-namespace {
-
-// The maximum number of image buffers to be allocated at any point of time.
-const size_t kMaxPendingBuffersCount = 2;
-
 }  // namespace
 
 PepperVideoRenderer2D::PepperVideoRenderer2D()
-    : instance_(nullptr),
-      event_handler_(nullptr),
-      merge_buffer_(nullptr),
-      dips_to_device_scale_(1.0f),
-      dips_to_view_scale_(1.0f),
-      flush_pending_(false),
-      frame_received_(false),
-      debug_dirty_region_(false),
-      callback_factory_(this),
-      weak_factory_(this) {
-}
+    : callback_factory_(this),
+      weak_factory_(this) {}
 
-PepperVideoRenderer2D::~PepperVideoRenderer2D() {
-  // The producer should now return any pending buffers. At this point, however,
-  // ReturnBuffer() tasks scheduled by the producer will not be delivered,
-  // so we free all the buffers once the producer's queue is empty.
-  base::WaitableEvent done_event(true, false);
-  software_video_renderer_->RequestReturnBuffers(
-      base::Bind(&base::WaitableEvent::Signal, base::Unretained(&done_event)));
-  done_event.Wait();
-
-  merge_buffer_ = nullptr;
-  while (!buffers_.empty()) {
-    FreeBuffer(buffers_.front());
-  }
-}
+PepperVideoRenderer2D::~PepperVideoRenderer2D() {}
 
 bool PepperVideoRenderer2D::Initialize(pp::Instance* instance,
                                        const ClientContext& context,
                                        EventHandler* event_handler) {
-  DCHECK(CalledOnValidThread());
+  DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(!instance_);
   DCHECK(!event_handler_);
   DCHECK(instance);
@@ -100,83 +66,29 @@ bool PepperVideoRenderer2D::Initialize(pp::Instance* instance,
 
   instance_ = instance;
   event_handler_ = event_handler;
-  scoped_ptr<FrameConsumerProxy> frame_consumer_proxy =
-      make_scoped_ptr(new FrameConsumerProxy(weak_factory_.GetWeakPtr()));
-  software_video_renderer_.reset(new SoftwareVideoRenderer(
-      context.main_task_runner(), context.decode_task_runner(),
-      frame_consumer_proxy.Pass()));
+  software_video_renderer_.reset(
+      new SoftwareVideoRenderer(context.decode_task_runner(), this));
 
   return true;
 }
 
 void PepperVideoRenderer2D::OnViewChanged(const pp::View& view) {
-  DCHECK(CalledOnValidThread());
-
-  bool view_changed = false;
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   pp::Rect pp_size = view.GetRect();
-  webrtc::DesktopSize new_dips_size(pp_size.width(), pp_size.height());
-  float new_dips_to_device_scale = view.GetDeviceScale();
-
-  if (!dips_size_.equals(new_dips_size) ||
-      dips_to_device_scale_ != new_dips_to_device_scale) {
-    view_changed = true;
-    dips_to_device_scale_ = new_dips_to_device_scale;
-    dips_size_ = new_dips_size;
-
-    // If |dips_to_device_scale_| is > 1.0 then the device is high-DPI, and
-    // there are actually |view_device_scale_| physical pixels for every one
-    // Density Independent Pixel (DIP).  If we specify a scale of 1.0 to
-    // Graphics2D then we can render at DIP resolution and let PPAPI up-scale
-    // for high-DPI devices.
-    dips_to_view_scale_ = 1.0f;
-    view_size_ = dips_size_;
-
-    // If the view's DIP dimensions don't match the source then let the frame
-    // producer do the scaling, and render at device resolution.
-    if (!dips_size_.equals(source_size_)) {
-      dips_to_view_scale_ = dips_to_device_scale_;
-      view_size_.set(ceilf(dips_size_.width() * dips_to_view_scale_),
-                     ceilf(dips_size_.height() * dips_to_view_scale_));
-    }
-
-    // Create a 2D rendering context at the chosen frame dimensions.
-    pp::Size pp_size = pp::Size(view_size_.width(), view_size_.height());
-    graphics2d_ = pp::Graphics2D(instance_, pp_size, false);
+  view_size_ = webrtc::DesktopSize(pp_size.width(), pp_size.height());
 
-    // Specify the scale from our coordinates to DIPs.
-    graphics2d_.SetScale(1.0f / dips_to_view_scale_);
+  // Update scale if graphics2d has been initialized.
+  if (!graphics2d_.is_null() && source_size_.width() > 0) {
+    graphics2d_.SetScale(static_cast<float>(view_size_.width()) /
+                         source_size_.width());
 
+    // Bind graphics2d_ again after changing the scale to work around
+    // crbug.com/521745 .
+    instance_->BindGraphics(graphics2d_);
     bool result = instance_->BindGraphics(graphics2d_);
-
-    // There is no good way to handle this error currently.
     DCHECK(result) << "Couldn't bind the device context.";
   }
-
-  // Ignore clip rectangle provided by the browser because it may not be
-  // correct. See crbug.com/360240 . In case when the plugin is not visible
-  // (e.g. another tab is selected) |clip_area_| is set to empty rectangle,
-  // otherwise it's set to a rectangle that covers the whole plugin.
-  //
-  // TODO(sergeyu): Use view.GetClipRect() here after bug 360240 is fixed.
-  webrtc::DesktopRect new_clip =
-      view.IsVisible() ? webrtc::DesktopRect::MakeWH(
-                             ceilf(pp_size.width() * dips_to_view_scale_),
-                             ceilf(pp_size.height() * dips_to_view_scale_))
-                       : webrtc::DesktopRect();
-  if (!clip_area_.equals(new_clip)) {
-    view_changed = true;
-
-    // YUV to RGB conversion may require even X and Y coordinates for
-    // the top left corner of the clipping area.
-    clip_area_ = AlignRect(new_clip);
-    clip_area_.IntersectWith(webrtc::DesktopRect::MakeSize(view_size_));
-  }
-
-  if (view_changed) {
-    software_video_renderer_->SetOutputSizeAndClip(view_size_, clip_area_);
-    AllocateBuffers();
-  }
 }
 
 void PepperVideoRenderer2D::EnableDebugDirtyRegion(bool enable) {
@@ -185,194 +97,132 @@ void PepperVideoRenderer2D::EnableDebugDirtyRegion(bool enable) {
 
 void PepperVideoRenderer2D::OnSessionConfig(
     const protocol::SessionConfig& config) {
-  DCHECK(CalledOnValidThread());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   software_video_renderer_->OnSessionConfig(config);
-  AllocateBuffers();
 }
 
 ChromotingStats* PepperVideoRenderer2D::GetStats() {
-  DCHECK(CalledOnValidThread());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   return software_video_renderer_->GetStats();
 }
 
 protocol::VideoStub* PepperVideoRenderer2D::GetVideoStub() {
-  DCHECK(CalledOnValidThread());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   return software_video_renderer_->GetVideoStub();
 }
 
-void PepperVideoRenderer2D::ApplyBuffer(const webrtc::DesktopSize& view_size,
-                                        const webrtc::DesktopRect& clip_area,
-                                        webrtc::DesktopFrame* buffer,
-                                        const webrtc::DesktopRegion& region,
-                                        const webrtc::DesktopRegion* shape) {
-  DCHECK(CalledOnValidThread());
+scoped_ptr<webrtc::DesktopFrame> PepperVideoRenderer2D::AllocateFrame(
+    const webrtc::DesktopSize& size) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  pp::ImageData buffer_data(instance_, PP_IMAGEDATAFORMAT_BGRA_PREMUL,
+                            pp::Size(size.width(), size.height()), false);
+  return make_scoped_ptr(new PepperDesktopFrame(buffer_data));
+}
+
+void PepperVideoRenderer2D::DrawFrame(scoped_ptr<webrtc::DesktopFrame> frame,
+                                      const base::Closure& done) {
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   if (!frame_received_) {
     event_handler_->OnVideoFirstFrameReceived();
     frame_received_ = true;
   }
-  // We cannot use the data in the buffer if its dimensions don't match the
-  // current view size.
-  if (!view_size_.equals(view_size)) {
-    FreeBuffer(buffer);
-    AllocateBuffers();
-  } else {
-    FlushBuffer(clip_area, buffer, region);
-    if (shape) {
-      if (!source_shape_ || !source_shape_->Equals(*shape)) {
-        source_shape_ = make_scoped_ptr(new webrtc::DesktopRegion(*shape));
-        event_handler_->OnVideoShape(source_shape_.get());
-      }
-    } else if (source_shape_) {
-      source_shape_ = nullptr;
-      event_handler_->OnVideoShape(nullptr);
-    }
-  }
-}
-
-void PepperVideoRenderer2D::ReturnBuffer(webrtc::DesktopFrame* buffer) {
-  DCHECK(CalledOnValidThread());
-
-  // Reuse the buffer if it is large enough, otherwise drop it on the floor
-  // and allocate a new one.
-  if (buffer->size().width() >= clip_area_.width() &&
-      buffer->size().height() >= clip_area_.height()) {
-    software_video_renderer_->DrawBuffer(buffer);
-  } else {
-    FreeBuffer(buffer);
-    AllocateBuffers();
-  }
-}
 
-void PepperVideoRenderer2D::SetSourceSize(
-    const webrtc::DesktopSize& source_size,
-    const webrtc::DesktopVector& source_dpi) {
-  DCHECK(CalledOnValidThread());
-
-  if (source_size_.equals(source_size) && source_dpi_.equals(source_dpi))
-    return;
+  bool size_changed = !source_size_.equals(frame->size());
+  if (size_changed) {
+    source_size_ = frame->size();
 
-  source_size_ = source_size;
-  source_dpi_ = source_dpi;
+    // Create a 2D rendering context with the new dimensions.
+    graphics2d_ = pp::Graphics2D(
+        instance_, pp::Size(source_size_.width(), source_size_.height()), true);
+    graphics2d_.SetScale(static_cast<float>(view_size_.width()) /
+                         source_size_.width());
+    bool result = instance_->BindGraphics(graphics2d_);
+    DCHECK(result) << "Couldn't bind the device context.";
+  }
 
-  // Notify JavaScript of the change in source size.
-  event_handler_->OnVideoSize(source_size, source_dpi);
-}
 
-FrameConsumer::PixelFormat PepperVideoRenderer2D::GetPixelFormat() {
-  return FORMAT_BGRA;
-}
+  if (size_changed || !source_dpi_.equals(frame->dpi())) {
+    source_dpi_ = frame->dpi();
 
-void PepperVideoRenderer2D::AllocateBuffers() {
-  if (clip_area_.width() == 0 || clip_area_.height() == 0)
-    return;
+    // Notify JavaScript of the change in source size.
+    event_handler_->OnVideoSize(source_size_, source_dpi_);
+  }
 
-  while (buffers_.size() < kMaxPendingBuffersCount) {
-    // Create an image buffer of the required size, but don't zero it.
-    pp::ImageData buffer_data(instance_, PP_IMAGEDATAFORMAT_BGRA_PREMUL,
-                              pp::Size(clip_area_.width(), clip_area_.height()),
-                              false);
-    if (buffer_data.is_null()) {
-      LOG(WARNING) << "Not enough memory for frame buffers.";
-      break;
+  const webrtc::DesktopRegion* shape = frame->shape();
+  if (shape) {
+    if (!source_shape_ || !source_shape_->Equals(*shape)) {
+      source_shape_ = make_scoped_ptr(new webrtc::DesktopRegion(*shape));
+      event_handler_->OnVideoShape(source_shape_.get());
     }
-
-    webrtc::DesktopFrame* buffer = new PepperDesktopFrame(buffer_data);
-    buffers_.push_back(buffer);
-    software_video_renderer_->DrawBuffer(buffer);
+  } else if (source_shape_) {
+    source_shape_ = nullptr;
+    event_handler_->OnVideoShape(nullptr);
   }
-}
 
-void PepperVideoRenderer2D::FreeBuffer(webrtc::DesktopFrame* buffer) {
-  DCHECK(std::find(buffers_.begin(), buffers_.end(), buffer) != buffers_.end());
-
-  buffers_.remove(buffer);
-  delete buffer;
-}
+  // If Debug dirty region is enabled then emit it.
+  if (debug_dirty_region_)
+    event_handler_->OnVideoFrameDirtyRegion(frame->updated_region());
+
+  const pp::ImageData& image_data =
+      static_cast<PepperDesktopFrame*>(frame.get())->buffer();
+  for (webrtc::DesktopRegion::Iterator i(frame->updated_region()); !i.IsAtEnd();
+       i.Advance()) {
+    graphics2d_.PaintImageData(image_data, pp::Point(0, 0),
+                               pp::Rect(i.rect().left(), i.rect().top(),
+                                        i.rect().width(), i.rect().height()));
+  }
 
-void PepperVideoRenderer2D::FlushBuffer(const webrtc::DesktopRect& clip_area,
-                                        webrtc::DesktopFrame* buffer,
-                                        const webrtc::DesktopRegion& region) {
-  // Defer drawing if the flush is already in progress.
-  if (flush_pending_) {
-    // |merge_buffer_| is guaranteed to be free here because we allocate only
-    // two buffers simultaneously. If more buffers are allowed this code should
-    // apply all pending changes to the screen.
-    DCHECK(merge_buffer_ == nullptr);
-
-    merge_clip_area_ = clip_area;
-    merge_buffer_ = buffer;
-    merge_region_ = region;
-    return;
+  if (!done.is_null()) {
+    pending_frames_done_callbacks_.push_back(
+        new base::ScopedClosureRunner(done));
   }
 
-  // Notify Pepper API about the updated areas and flush pixels to the screen.
-  base::Time start_time = base::Time::Now();
+  need_flush_ = true;
 
-  for (webrtc::DesktopRegion::Iterator i(region); !i.IsAtEnd(); i.Advance()) {
-    webrtc::DesktopRect rect = i.rect();
+  Flush();
+}
 
-    // Re-clip |region| with the current clipping area |clip_area_| because
-    // the latter could change from the time the buffer was drawn.
-    rect.IntersectWith(clip_area_);
-    if (rect.is_empty())
-      continue;
+FrameConsumer::PixelFormat PepperVideoRenderer2D::GetPixelFormat() {
+  return FORMAT_BGRA;
+}
 
-    // Specify the rectangle coordinates relative to the clipping area.
-    rect.Translate(-clip_area.left(), -clip_area.top());
+void PepperVideoRenderer2D::Flush() {
+  DCHECK(thread_checker_.CalledOnValidThread());
 
-    // Pepper Graphics 2D has a strange and badly documented API that the
-    // point here is the offset from the source rect. Why?
-    graphics2d_.PaintImageData(
-        static_cast<PepperDesktopFrame*>(buffer)->buffer(),
-        pp::Point(clip_area.left(), clip_area.top()),
-        pp::Rect(rect.left(), rect.top(), rect.width(), rect.height()));
-  }
+  if (flush_pending_ || !need_flush_)
+    return;
 
-  // Notify the producer that some parts of the region weren't painted because
-  // the clipping area has changed already.
-  if (!clip_area.equals(clip_area_)) {
-    webrtc::DesktopRegion not_painted = region;
-    not_painted.Subtract(clip_area_);
-    if (!not_painted.is_empty()) {
-      software_video_renderer_->InvalidateRegion(not_painted);
-    }
-  }
+  need_flush_ = false;
+
+  // Move callbacks from |pending_frames_done_callbacks_| to
+  // |flushing_frames_done_callbacks_| so the callbacks are called when flush is
+  // finished.
+  DCHECK(flushing_frames_done_callbacks_.empty());
+  flushing_frames_done_callbacks_ = pending_frames_done_callbacks_.Pass();
 
   // Flush the updated areas to the screen.
-  pp::CompletionCallback callback = callback_factory_.NewCallback(
-      &PepperVideoRenderer2D::OnFlushDone, start_time, buffer);
-  int error = graphics2d_.Flush(callback);
+  int error = graphics2d_.Flush(
+      callback_factory_.NewCallback(&PepperVideoRenderer2D::OnFlushDone));
   CHECK(error == PP_OK_COMPLETIONPENDING);
   flush_pending_ = true;
-
-  // If Debug dirty region is enabled then emit it.
-  if (debug_dirty_region_) {
-    event_handler_->OnVideoFrameDirtyRegion(region);
-  }
 }
 
-void PepperVideoRenderer2D::OnFlushDone(int result,
-                                        const base::Time& paint_start,
-                                        webrtc::DesktopFrame* buffer) {
-  DCHECK(CalledOnValidThread());
-  DCHECK(flush_pending_);
-
-  software_video_renderer_->GetStats()->RecordPaintTime(
-      (base::Time::Now() - paint_start).InMilliseconds());
+void PepperVideoRenderer2D::OnFlushDone(int result) {
+  DCHECK(thread_checker_.CalledOnValidThread());
 
+  DCHECK(flush_pending_);
   flush_pending_ = false;
-  ReturnBuffer(buffer);
 
-  // If there is a buffer queued for rendering then render it now.
-  if (merge_buffer_) {
-    buffer = merge_buffer_;
-    merge_buffer_ = nullptr;
-    FlushBuffer(merge_clip_area_, buffer, merge_region_);
-  }
+  // Call all callbacks for the frames we've just flushed.
+  flushing_frames_done_callbacks_.clear();
+
+  // Flush again if necessary.
+  Flush();
 }
 
 }  // namespace remoting