gecko/gfx/layers/ImageLayers.h

477 lines
16 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Corporation code.
*
* The Initial Developer of the Original Code is Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Robert O'Callahan <robert@ocallahan.org>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef GFX_IMAGELAYER_H
#define GFX_IMAGELAYER_H
#include "Layers.h"
#include "gfxPattern.h"
#include "nsThreadUtils.h"
#include "nsCoreAnimationSupport.h"
#include "mozilla/Monitor.h"
#include "mozilla/TimeStamp.h"
namespace mozilla {
namespace layers {
enum StereoMode {
STEREO_MODE_MONO,
STEREO_MODE_LEFT_RIGHT,
STEREO_MODE_RIGHT_LEFT,
STEREO_MODE_BOTTOM_TOP,
STEREO_MODE_TOP_BOTTOM
};
/**
* A class representing a buffer of pixel data. The data can be in one
* of various formats including YCbCr.
*
* Create an image using an ImageContainer. Fill the image with data, and
* then call ImageContainer::SetImage to display it. An image must not be
* modified after calling SetImage. Image implementations do not need to
* perform locking; when filling an Image, the Image client is responsible
* for ensuring only one thread accesses the Image at a time, and after
* SetImage the image is immutable.
*
* When resampling an Image, only pixels within the buffer should be
* sampled. For example, cairo images should be sampled in EXTEND_PAD mode.
*/
class THEBES_API Image {
THEBES_INLINE_DECL_THREADSAFE_REFCOUNTING(Image)
public:
virtual ~Image() {}
enum Format {
/**
* The PLANAR_YCBCR format creates a PlanarYCbCrImage. All backends should
* support this format, because the Ogg video decoder depends on it.
* The maximum image width and height is 16384.
*/
PLANAR_YCBCR,
/**
* The CAIRO_SURFACE format creates a CairoImage. All backends should
* support this format, because video rendering sometimes requires it.
*
* This format is useful even though a ThebesLayer could be used.
* It makes it easy to render a cairo surface when another Image format
* could be used. It can also avoid copying the surface data in some
* cases.
*
* Images in CAIRO_SURFACE format should only be created and
* manipulated on the main thread, since the underlying cairo surface
* is main-thread-only.
*/
CAIRO_SURFACE,
/**
* The MAC_IO_SURFACE format creates a MacIOSurfaceImage. This
* is only supported on Mac with OpenGL layers.
*
* It wraps an IOSurface object and binds it directly to a GL texture.
*/
MAC_IO_SURFACE
};
Format GetFormat() { return mFormat; }
void* GetImplData() { return mImplData; }
protected:
Image(void* aImplData, Format aFormat) :
mImplData(aImplData),
mFormat(aFormat)
{}
void* mImplData;
Format mFormat;
};
/**
* A class that manages Images for an ImageLayer. The only reason
* we need a separate class here is that ImageLayers aren't threadsafe
* (because layers can only be used on the main thread) and we want to
* be able to set the current Image from any thread, to facilitate
* video playback without involving the main thread, for example.
*/
class THEBES_API ImageContainer {
THEBES_INLINE_DECL_THREADSAFE_REFCOUNTING(ImageContainer)
public:
ImageContainer() :
mMonitor("ImageContainer"),
mPaintCount(0),
mPreviousImagePainted(PR_FALSE)
{}
virtual ~ImageContainer() {}
/**
* Create an Image in one of the given formats.
* Picks the "best" format from the list and creates an Image of that
* format.
* Returns null if this backend does not support any of the formats.
* Can be called on any thread. This method takes mMonitor when accessing
* thread-shared state.
*/
virtual already_AddRefed<Image> CreateImage(const Image::Format* aFormats,
PRUint32 aNumFormats) = 0;
/**
* Set an Image as the current image to display. The Image must have
* been created by this ImageContainer.
* Can be called on any thread. This method takes mMonitor when accessing
* thread-shared state.
*
* The Image data must not be modified after this method is called!
*/
virtual void SetCurrentImage(Image* aImage) = 0;
/**
* Get the current Image.
* This has to add a reference since otherwise there are race conditions
* where the current image is destroyed before the caller can add
* a reference.
* Can be called on any thread. This method takes mMonitor when accessing
* thread-shared state.
* Implementations must call CurrentImageChanged() while holding mMonitor.
*
*/
virtual already_AddRefed<Image> GetCurrentImage() = 0;
/**
* Get the current image as a gfxASurface. This is useful for fallback
* rendering.
* This can only be called from the main thread, since cairo objects
* can only be used from the main thread.
* This is defined here and not on Image because it's possible (likely)
* that some backends will make an Image "ready to draw" only when it
* becomes the current image for an image container.
* Returns null if there is no current image.
* Returns the size in aSize.
* The returned surface will never be modified. The caller must not
* modify it.
* Can be called on any thread. This method takes mMonitor when accessing
* thread-shared state.
*/
virtual already_AddRefed<gfxASurface> GetCurrentAsSurface(gfxIntSize* aSizeResult) = 0;
/**
* Returns the layer manager for this container. This can only
* be used on the main thread, since layer managers should only be
* accessed on the main thread.
*/
LayerManager* Manager()
{
NS_PRECONDITION(NS_IsMainThread(), "Must be called on main thread");
return mManager;
}
/**
* Returns the size of the image in pixels.
* Can be called on any thread. This method takes mMonitor when accessing
* thread-shared state.
*/
virtual gfxIntSize GetCurrentSize() = 0;
/**
* Set a new layer manager for this image container. It must be
* either of the same type as the container's current layer manager,
* or null. TRUE is returned on success. Main thread only.
*/
virtual PRBool SetLayerManager(LayerManager *aManager) = 0;
/**
* Sets a size that the image is expected to be rendered at.
* This is a hint for image backends to optimize scaling.
* Default implementation in this class is to ignore the hint.
* Can be called on any thread. This method takes mMonitor when accessing
* thread-shared state.
*/
virtual void SetScaleHint(const gfxIntSize& /* aScaleHint */) { }
/**
* Get the layer manager type this image container was created with,
* presumably its users might want to do something special if types do not
* match. Can be called on any thread.
*/
virtual LayerManager::LayersBackend GetBackendType() = 0;
/**
* Returns the time at which the currently contained image was first
* painted. This is reset every time a new image is set as the current
* image. Note this may return a null timestamp if the current image
* has not yet been painted. Can be called from any thread.
*/
TimeStamp GetPaintTime() {
MonitorAutoEnter mon(mMonitor);
return mPaintTime;
}
/**
* Returns the number of images which have been contained in this container
* and painted at least once. Can be called from any thread.
*/
PRUint32 GetPaintCount() {
MonitorAutoEnter mon(mMonitor);
return mPaintCount;
}
/**
* Increments mPaintCount if this is the first time aPainted has been
* painted, and sets mPaintTime if the painted image is the current image.
* current image. Can be called from any thread.
*/
void NotifyPaintedImage(Image* aPainted) {
MonitorAutoEnter mon(mMonitor);
nsRefPtr<Image> current = GetCurrentImage();
if (aPainted == current) {
if (mPaintTime.IsNull()) {
mPaintTime = TimeStamp::Now();
mPaintCount++;
}
} else if (!mPreviousImagePainted) {
// While we were painting this image, the current image changed. We
// still must count it as painted, but can't set mPaintTime, since we're
// no longer the current image.
mPaintCount++;
mPreviousImagePainted = PR_TRUE;
}
}
protected:
typedef mozilla::Monitor Monitor;
LayerManager* mManager;
// Monitor to protect thread safe access to the "current image", and any
// other state which is shared between threads.
Monitor mMonitor;
ImageContainer(LayerManager* aManager) :
mManager(aManager),
mMonitor("ImageContainer"),
mPaintCount(0),
mPreviousImagePainted(PR_FALSE)
{}
// Performs necessary housekeeping to ensure the painted frame statistics
// are accurate. Must be called by SetCurrentImage() implementations with
// mMonitor held.
void CurrentImageChanged() {
mMonitor.AssertCurrentThreadIn();
mPreviousImagePainted = !mPaintTime.IsNull();
mPaintTime = TimeStamp();
}
// Number of contained images that have been painted at least once. It's up
// to the ImageContainer implementation to ensure accesses to this are
// threadsafe.
PRUint32 mPaintCount;
// Time stamp at which the current image was first painted. It's up to the
// ImageContainer implementation to ensure accesses to this are threadsafe.
TimeStamp mPaintTime;
// Denotes whether the previous image was painted.
PRPackedBool mPreviousImagePainted;
};
/**
* A Layer which renders an Image.
*/
class THEBES_API ImageLayer : public Layer {
public:
/**
* CONSTRUCTION PHASE ONLY
* Set the ImageContainer. aContainer must have the same layer manager
* as this layer.
*/
void SetContainer(ImageContainer* aContainer)
{
NS_ASSERTION(!aContainer->Manager() || aContainer->Manager() == Manager(),
"ImageContainer must have the same manager as the ImageLayer");
mContainer = aContainer;
}
/**
* CONSTRUCTION PHASE ONLY
* Set the filter used to resample this image if necessary.
*/
void SetFilter(gfxPattern::GraphicsFilter aFilter) { mFilter = aFilter; }
ImageContainer* GetContainer() { return mContainer; }
gfxPattern::GraphicsFilter GetFilter() { return mFilter; }
MOZ_LAYER_DECL_NAME("ImageLayer", TYPE_IMAGE)
virtual void ComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface)
{
// Snap image edges to pixel boundaries
gfxRect snap(0, 0, 0, 0);
if (mContainer) {
gfxIntSize size = mContainer->GetCurrentSize();
snap.SizeTo(gfxSize(size.width, size.height));
}
// Snap our local transform first, and snap the inherited transform as well.
// This makes our snapping equivalent to what would happen if our content
// was drawn into a ThebesLayer (gfxContext would snap using the local
// transform, then we'd snap again when compositing the ThebesLayer).
mEffectiveTransform =
SnapTransform(GetLocalTransform(), snap, nsnull)*
SnapTransform(aTransformToSurface, gfxRect(0, 0, 0, 0), nsnull);
}
protected:
ImageLayer(LayerManager* aManager, void* aImplData)
: Layer(aManager, aImplData), mFilter(gfxPattern::FILTER_GOOD) {}
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
nsRefPtr<ImageContainer> mContainer;
gfxPattern::GraphicsFilter mFilter;
};
/****** Image subtypes for the different formats ******/
/**
* We assume that the image data is in the REC 470M color space (see
* Theora specification, section 4.3.1).
*
* The YCbCr format can be:
*
* 4:4:4 - CbCr width/height are the same as Y.
* 4:2:2 - CbCr width is half that of Y. Height is the same.
* 4:2:0 - CbCr width and height is half that of Y.
*
* The color format is detected based on the height/width ratios
* defined above.
*
* The Image that is rendered is the picture region defined by
* mPicX, mPicY and mPicSize. The size of the rendered image is
* mPicSize, not mYSize or mCbCrSize.
*/
class THEBES_API PlanarYCbCrImage : public Image {
public:
struct Data {
// Luminance buffer
PRUint8* mYChannel;
PRInt32 mYStride;
gfxIntSize mYSize;
// Chroma buffers
PRUint8* mCbChannel;
PRUint8* mCrChannel;
PRInt32 mCbCrStride;
gfxIntSize mCbCrSize;
// Picture region
PRUint32 mPicX;
PRUint32 mPicY;
gfxIntSize mPicSize;
StereoMode mStereoMode;
};
enum {
MAX_DIMENSION = 16384
};
/**
* This makes a copy of the data buffers.
* XXX Eventually we will change this to not make a copy of the data,
* Right now it doesn't matter because the BasicLayer implementation
* does YCbCr conversion here anyway.
*/
virtual void SetData(const Data& aData) = 0;
protected:
PlanarYCbCrImage(void* aImplData) : Image(aImplData, PLANAR_YCBCR) {}
};
/**
* Currently, the data in a CairoImage surface is treated as being in the
* device output color space.
*/
class THEBES_API CairoImage : public Image {
public:
struct Data {
gfxASurface* mSurface;
gfxIntSize mSize;
};
/**
* This can only be called on the main thread. It may add a reference
* to the surface (which will eventually be released on the main thread).
* The surface must not be modified after this call!!!
*/
virtual void SetData(const Data& aData) = 0;
protected:
CairoImage(void* aImplData) : Image(aImplData, CAIRO_SURFACE) {}
};
#ifdef XP_MACOSX
class THEBES_API MacIOSurfaceImage : public Image {
public:
struct Data {
nsIOSurface* mIOSurface;
};
/**
* This can only be called on the main thread. It may add a reference
* to the surface (which will eventually be released on the main thread).
* The surface must not be modified after this call!!!
*/
virtual void SetData(const Data& aData) = 0;
/**
* Temporary hacks to force plugin drawing during an empty transaction.
* This should not be used for anything else, and will be removed
* when async plugin rendering is complete.
*/
typedef void (*UpdateSurfaceCallback)(ImageContainer* aContainer, void* aInstanceOwner);
virtual void SetUpdateCallback(UpdateSurfaceCallback aCallback, void* aInstanceOwner) = 0;
typedef void (*DestroyCallback)(void* aInstanceOwner);
virtual void SetDestroyCallback(DestroyCallback aCallback) = 0;
protected:
MacIOSurfaceImage(void* aImplData) : Image(aImplData, MAC_IO_SURFACE) {}
};
#endif
}
}
#endif /* GFX_IMAGELAYER_H */