cc/proto/compositor_message.proto

// 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.

syntax = "proto2";

option optimize_for = LITE_RUNTIME;

import "client_state_update.proto";
import "layer_tree_host.proto";

package cc.proto;

// A top level message for serialized state used by the compositor remote
// channels.
// TODO(khushalsagar): Remove CompositorMessage and stop using
// RemoteProtoChannel to plumb these to/from the browser. See crbug.com/648442
message CompositorMessage {
  // Engine -> Client
  // Frame Update.
  optional LayerTreeHost layer_tree_host = 3;

  // Client -> Engine
  // Sent from the client to the engine when a frame update was processed
  // on the client.
  optional bool frame_ack = 4;

  // Client -> Engine
  // Reports any changes made to the main thread state on the compositor thread
  // on the client.
  optional ClientStateUpdate client_state_update = 5;

  // Engine -> Client
  // Acknowledges the application of the client state update to the associated
  // state on the engine.
  // If the application of the update resulted in any additional changes to the
  // state on the engine, the ack will always be bundled with the resulting
  // frame update.
  optional bool client_state_update_ack = 6;
}