gecko-dev/gfx/layers/ipc/PCanvas.ipdl

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: sw=2 ts=8 et : */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

using mozilla::CrossProcessSemaphoreHandle from "mozilla/ipc/CrossProcessSemaphore.h";
using mozilla::layers::TextureType from "mozilla/layers/LayersTypes.h";
using mozilla::ipc::SharedMemoryBasic::Handle from "mozilla/ipc/SharedMemoryBasic.h";

namespace mozilla {
namespace layers {

/**
 * PCanvas is the IPDL for recorded Canvas drawing.
 */
async refcounted protocol PCanvas {
parent:
  /**
   * Initialize a CanvasTranslator for a particular TextureType, which
   * translates events from a CanvasEventRingBuffer. aReadHandle is the shared
   * memory handle for the ring buffer. aReaderSem and aWriterSem are handles
   * for the semaphores to handle waiting on either side.
   */
  async InitTranslator(TextureType aTextureType, Handle aReadHandle,
                       CrossProcessSemaphoreHandle aReaderSem,
                       CrossProcessSemaphoreHandle aWriterSem);

  /**
   * Used to tell the CanvasTranslator to start translating again after it has
   * stopped due to a timeout waiting for events.
   */
  async ResumeTranslation();

  child:
  /**
   * Notify that the canvas device used by the translator has changed.
   */
  async NotifyDeviceChanged();
};

} // layers
} // mozilla