cc/ipc/mojo_compositor_frame_sink.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.

module cc.mojom;

import "cc/ipc/compositor_frame.mojom";
import "cc/ipc/returned_resource.mojom";

// A MojoCompositorFrameSink is an interface for receiving CompositorFrame
// structs. A CompositorFrame contains the complete output meant for display.
// Each time a client has a graphical update, and receives an OnBeginFrame, it
// is responsible for creating a CompositorFrame to update its portion of the
// screen.
interface MojoCompositorFrameSink {
  // After the submitted frame is either drawn for the first time by the display
  // compositor or discarded, the callback will be called. Clients should use
  // this acknowledgement to ratelimit frame submissions.
  // TODO(fsamuel): We should support identifying the CF in the callback.
  SubmitCompositorFrame(cc.mojom.CompositorFrame frame) => ();

  // Lets the display compositor know that the client wishes to receive the next
  // BeginFrame event.
  SetNeedsBeginFrame(bool needs_begin_frame);

  // TODO(fsamuel): ReadbackBitmap API would be useful here.
};

interface MojoCompositorFrameSinkClient {
  ReturnResources(array<cc.mojom.ReturnedResource> resources);
};