gecko/gfx/layers/ipc/PCompositor.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/. */

include LayersSurfaces;
include protocol PGrallocBuffer;
include protocol PLayerTransaction;
include "mozilla/GfxMessageUtils.h";
include "nsRegion.h";

using struct mozilla::null_t from "ipc/IPCMessageUtils.h";
using struct mozilla::layers::TextureFactoryIdentifier from "mozilla/layers/CompositorTypes.h";
using struct mozilla::layers::FrameMetrics from "FrameMetrics.h";
using mozilla::layers::FrameMetrics::ViewID from "FrameMetrics.h";
using mozilla::layers::LayersBackend from "mozilla/layers/LayersTypes.h";
using mozilla::CrossProcessMutexHandle from "mozilla/ipc/CrossProcessMutex.h";
using mozilla::ipc::SharedMemoryBasic::Handle from "mozilla/ipc/SharedMemoryBasic.h";
using class mozilla::TimeStamp from "mozilla/TimeStamp.h";

namespace mozilla {
namespace layers {


/**
 * The PCompositor protocol is used to manage communication between
 * the main thread and the compositor thread context. It's primary
 * purpose is to manage the PLayerTransaction sub protocol.
 */
// This should really be 'sync', but we're using 'rpc' as a workaround
// for Bug 716631.
intr protocol PCompositor
{
  // A Compositor manages a single Layer Manager (PLayerTransaction)
  manages PLayerTransaction;

child:
  // The child should invalidate everything so that the whole window is redrawn.
  async InvalidateAll();

  // The compositor completed a layers transaction. id is the layers id
  // of the child layer tree that was composited (or 0 when notifying
  // the root layer tree).
  async DidComposite(uint64_t id);

parent:

  // The child is about to be destroyed, so perform any necessary cleanup.
  sync WillStop();

  // Clean up in preparation for own destruction.
  sync Stop();

  // Pause/resume the compositor. These are intended to be used on mobile, when
  // the compositor needs to pause/resume in lockstep with the application.
  sync Pause();
  sync Resume();

  async NotifyChildCreated(uint64_t id);

  // Make a snapshot of the content that would have been drawn to our
  // render target at the time this message is received.  If the size
  // or format of |inSnapshot| doesn't match our render target,
  // results are undefined.
  //
  // NB: this message will result in animations, transforms, effects,
  // and so forth being interpolated.  That's what we want to happen.
  sync MakeSnapshot(SurfaceDescriptor inSnapshot)
    returns (SurfaceDescriptor outSnapshot);

  // Make sure any pending composites are started immediately and
  // block until they are completed.
  sync FlushRendering();

  sync StartFrameTimeRecording(int32_t bufferSize)
    returns (uint32_t startIndex);

  sync StopFrameTimeRecording(uint32_t startIndex)
    returns (float[] intervals);

  // layersBackendHints is an ordered list of preffered backends where
  // layersBackendHints[0] is the best backend. If any hints are LayersBackend::LAYERS_NONE
  // that hint is ignored.
  sync PLayerTransaction(LayersBackend[] layersBackendHints, uint64_t id)
    returns (TextureFactoryIdentifier textureFactoryIdentifier, bool success);

  // Notify the compositor that a region of the screen has been invalidated.
  async NotifyRegionInvalidated(nsIntRegion region);

child:
  // Send back Compositor Frame Metrics from APZCs so tiled layers can
  // update progressively.
  async SharedCompositorFrameMetrics(Handle metrics, CrossProcessMutexHandle mutex, uint32_t aAPZCId);
  async ReleaseSharedCompositorFrameMetrics(ViewID aId, uint32_t aAPZCId);
};

} // layers
} // mozilla