gecko/gfx/layers/ipc/ImageContainerParent.h
2012-07-30 17:20:58 +03:00

139 lines
4.6 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* 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/. */
#ifndef MOZILLA_GFX_IMAGECONTAINERPARENT_H
#define MOZILLA_GFX_IMAGECONTAINERPARENT_H
#include "mozilla/layers/PImageContainerParent.h"
namespace mozilla {
namespace layers {
class ImageBridgeParent;
/**
* Handles reception of SharedImages on the compositor side.
*
* Received SharedImages are stored in a global map that can be accessed
* from the compositor thread only.
* This way, ShadowImageLayers can access SharedImages using the image's ID
* without holding a reference to the ImageContainerParent.
* The ID is passed to the ShadowImageLayer through a regular PCompositor
* transaction.
* All ImageContainerParent's method must be called from the Compositor thread
* only.
*/
class ImageContainerParent : public PImageContainerParent
{
public:
ImageContainerParent(ImageBridgeParent* aBridge, PRUint32 aContainerID);
~ImageContainerParent();
// Overriden from PImageContainerParent (see ImageContainer.ipdl)
bool RecvPublishImage(const SharedImage& aImage) MOZ_OVERRIDE;
// Overriden from PImageContainerParent (see DoStop)
bool RecvStop() MOZ_OVERRIDE;
// Overriden from PImageContainerParent (see ImageContainer.ipdl)
bool Recv__delete__() MOZ_OVERRIDE;
// Overriden from PImageContainerParent (see ImageContainer.ipdl)
bool RecvFlush() MOZ_OVERRIDE;
/**
* Called by RecvStop and ImageBridgeChild::RecvStop.
*
* puts the ImageContainerChild in a state in which it cannot send async
* messages to the child side, in order to not race with the upcomming
* __delete__ message.
*/
void DoStop();
static SharedImage* GetSharedImage(PRUint64 aID);
/**
* Every time a SharedImage is swaped, a version counter associated with the
* iamge's ID is incremented. This allows ImageLayers to compare the current
* image with the one that has been displayed last (in particular on OGL
* backend we can avoid uploading the same texture twice if composition
* happens more frequently than ImageBridge transfers);
*/
static PRUint32 GetSharedImageVersion(PRUint64 aID);
/**
* Returns true if this ID exists in the global SharedImage table.
*
* Should be called from the Compositor thread
*/
static bool IsExistingID(PRUint64 aID);
/**
* Associates an image with a compositor ID, so that when the ImageContainerParent
* receives an image with a given ID, it can lookup the right compositor and
* ask it to recomposite.
*
* This should be called by the ShadowImageLayer each time it renders a shared
* image, to make sure the compositor ID is updated if the image stream changes
* compositor (for instance when the tab containing the stream is dragged to
* another window).
*/
static bool SetCompositorIDForImage(PRUint64 aImageID, PRUint64 aCompositorID);
/**
* Must be called on the compositor thread.
*/
static PRUint64 GetCompositorIDForImage(PRUint64 aImageID);
/**
* Must be called before the first use of ImageBridge and Compositor.
*/
static void CreateSharedImageMap();
/**
* Must be called after the last use of ImageBridge and Compositor.
*/
static void DestroySharedImageMap();
protected:
virtual PGrallocBufferParent*
AllocPGrallocBuffer(const gfxIntSize&, const gfxContentType&,
MaybeMagicGrallocBufferHandle*) MOZ_OVERRIDE
{ return nullptr; }
virtual bool
DeallocPGrallocBuffer(PGrallocBufferParent* actor) MOZ_OVERRIDE
{ return false; }
/**
* Sets the image associated with t aID in the global SharedImage table and
* returns the previous image that was associated with aID.
*
* If the global SharedImage table does not yet have an entry for aID, it
* creates one and returns nullptr since there was no previous image for aID.
* Must be called from the Compositor thread.
*/
static SharedImage* SwapSharedImage(PRUint64 aID, SharedImage* aImage);
/**
* Removes an entry from the global SharedImage table and returns the
* SharedImage that was stored in the table for aID or nullptr if there
* was no entry for aID.
*
* It is safe to call this function on an ID that does not exist in the table.
* Must be called from the Compositor thread.
*/
static SharedImage* RemoveSharedImage(PRUint64 aID);
private:
PRUint64 mID;
ImageBridgeParent* mBridge;
bool mStop;
};
} // namespace
} // namespace
#endif