third_party/WebKit/Source/modules/mediacapturefromelement/TimedCanvasDrawListener.cpp

// Copyright 2015 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 "modules/mediacapturefromelement/TimedCanvasDrawListener.h"

#include <memory>
#include "core/dom/ExecutionContext.h"
#include "public/platform/TaskType.h"
#include "third_party/skia/include/core/SkImage.h"

namespace blink {

TimedCanvasDrawListener::TimedCanvasDrawListener(
    std::unique_ptr<WebCanvasCaptureHandler> handler,
    double frame_rate,
    ExecutionContext* context)
    : CanvasDrawListener(std::move(handler)),
      frame_interval_(TimeDelta::FromSecondsD(1 / frame_rate)),
      request_frame_timer_(context->GetTaskRunner(TaskType::kUnthrottled),
                           this,
                           &TimedCanvasDrawListener::RequestFrameTimerFired) {}

TimedCanvasDrawListener::~TimedCanvasDrawListener() {}

// static
TimedCanvasDrawListener* TimedCanvasDrawListener::Create(
    std::unique_ptr<WebCanvasCaptureHandler> handler,
    double frame_rate,
    ExecutionContext* context) {
  TimedCanvasDrawListener* listener =
      new TimedCanvasDrawListener(std::move(handler), frame_rate, context);
  listener->request_frame_timer_.StartRepeating(listener->frame_interval_,
                                                BLINK_FROM_HERE);
  return listener;
}

void TimedCanvasDrawListener::SendNewFrame(
    sk_sp<SkImage> image,
    base::WeakPtr<WebGraphicsContext3DProviderWrapper> context_provider) {
  frame_capture_requested_ = false;
  CanvasDrawListener::SendNewFrame(image, context_provider);
}

void TimedCanvasDrawListener::RequestFrameTimerFired(TimerBase*) {
  // TODO(emircan): Measure the jitter and log, see crbug.com/589974.
  frame_capture_requested_ = true;
}

}  // namespace blink