mojo/services/media/core/interfaces/timeline_controller.mojom

// Copyright 2016 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.

[DartPackage="mojo_services"]
module mojo.media;

import "mojo/services/media/common/interfaces/timelines.mojom";

// Timing controller for a media graph.
interface MediaTimelineController {
  // Associates a control site with the controller.
  AddControlSite(MediaTimelineControlSite control_site);

  // Gets a timeline control site interface for the controller.
  GetControlSite(MediaTimelineControlSite& control_site);
};

// Media graph component controlled by a MediaTimelineController.
interface MediaTimelineControlSite {
  const uint64 kInitialStatus = 0;

  // Gets the status. To get the status immediately, call
  // GetStatus(kInitialStatus). To get updates thereafter, pass
  // the version sent in the previous callback.
  GetStatus(uint64 version_last_seen) =>
      (uint64 version, MediaTimelineControlSiteStatus status);

  // Gets a timeline consumer interface for the control site.
  GetTimelineConsumer(TimelineConsumer& timeline_consumer);
};

// Status returned by MediaTimelineControlSite's GetStatus method.
struct MediaTimelineControlSiteStatus {
  // Current timeline transform.
  mojo.TimelineTransform timeline_transform;

  // Indicates whether presentation has reached end-of-stream.
  bool end_of_stream;
};