third_party/blink/renderer/platform/graphics/begin_frame_provider.cc

// Copyright 2018 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 "third_party/blink/renderer/platform/graphics/begin_frame_provider.h"

#include "base/single_thread_task_runner.h"
#include "third_party/blink/public/platform/interface_provider.h"
#include "third_party/blink/public/platform/platform.h"
#include "third_party/blink/renderer/platform/scheduler/public/thread_scheduler.h"
#include "third_party/blink/renderer/platform/web_task_runner.h"

namespace blink {

BeginFrameProvider::BeginFrameProvider(
    const BeginFrameProviderParams& begin_frame_provider_params,
    BeginFrameProviderClient* client)
    : needs_begin_frame_(false),
      requested_needs_begin_frame_(false),
      cfs_binding_(this),
      efs_binding_(this),
      frame_sink_id_(begin_frame_provider_params.frame_sink_id),
      parent_frame_sink_id_(begin_frame_provider_params.parent_frame_sink_id),
      begin_frame_client_(client),
      weak_factory_(this) {}

void BeginFrameProvider::ResetCompositorFrameSink() {
  compositor_frame_sink_.reset();
  efs_binding_.Close();
  cfs_binding_.Close();
  if (needs_begin_frame_) {
    needs_begin_frame_ = false;
    RequestBeginFrame();
  }
}

void BeginFrameProvider::OnMojoConnectionError(uint32_t custom_reason,
                                               const std::string& description) {
  if (custom_reason) {
    DLOG(ERROR) << description;
  }
  ResetCompositorFrameSink();
}

bool BeginFrameProvider::IsValidFrameProvider() {
  if (!parent_frame_sink_id_.is_valid() || !frame_sink_id_.is_valid()) {
    return false;
  }

  return true;
}

void BeginFrameProvider::CreateCompositorFrameSinkIfNeeded() {
  if (!parent_frame_sink_id_.is_valid() || !frame_sink_id_.is_valid()) {
    return;
  }

  if (compositor_frame_sink_.is_bound())
    return;

  mojom::blink::EmbeddedFrameSinkProviderPtr provider;
  Platform::Current()->GetInterfaceProvider()->GetInterface(
      mojo::MakeRequest(&provider));

  scoped_refptr<base::SingleThreadTaskRunner> task_runner =
      ThreadScheduler::Current()->CompositorTaskRunner();

  mojom::blink::EmbeddedFrameSinkClientPtr efs_client;
  efs_binding_.Bind(mojo::MakeRequest(&efs_client), task_runner);

  viz::mojom::blink::CompositorFrameSinkClientPtr client;
  cfs_binding_.Bind(mojo::MakeRequest(&client), task_runner);

  provider->CreateSimpleCompositorFrameSink(
      parent_frame_sink_id_, frame_sink_id_, std::move(efs_client),
      std::move(client), mojo::MakeRequest(&compositor_frame_sink_));

  compositor_frame_sink_.set_connection_error_with_reason_handler(
      base::BindOnce(&BeginFrameProvider::OnMojoConnectionError,
                     weak_factory_.GetWeakPtr()));
}

void BeginFrameProvider::RequestBeginFrame() {
  requested_needs_begin_frame_ = true;
  if (needs_begin_frame_) {
    return;
  }

  CreateCompositorFrameSinkIfNeeded();

  needs_begin_frame_ = true;
  compositor_frame_sink_->SetNeedsBeginFrame(true);
}

void BeginFrameProvider::OnBeginFrame(const viz::BeginFrameArgs& args) {
  // If there was no need for a BeginFrame, just skip it.
  if (needs_begin_frame_ && requested_needs_begin_frame_) {
    requested_needs_begin_frame_ = false;
    begin_frame_client_->BeginFrame();
  } else {
    if (!requested_needs_begin_frame_) {
      needs_begin_frame_ = false;
      compositor_frame_sink_->SetNeedsBeginFrame(false);
    }
  }

  compositor_frame_sink_->DidNotProduceFrame(viz::BeginFrameAck(args, false));
}

}  // namespace blink