pjs/gfx/layers/Layers.h

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/* -*- Mode: C++; tab-width: 2; 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_LAYERS_H
#define GFX_LAYERS_H
#include "gfxTypes.h"
#include "gfxASurface.h"
#include "nsRegion.h"
#include "nsPoint.h"
#include "nsRect.h"
#include "nsISupportsImpl.h"
#include "nsAutoPtr.h"
#include "gfx3DMatrix.h"
#include "gfxColor.h"
#include "gfxPattern.h"
#include "nsTArray.h"
#include "nsThreadUtils.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/TimeStamp.h"
#if defined(DEBUG) || defined(PR_LOGGING)
# include <stdio.h> // FILE
# include "prlog.h"
# define MOZ_LAYERS_HAVE_LOG
# define MOZ_LAYERS_LOG(_args) \
PR_LOG(LayerManager::GetLog(), PR_LOG_DEBUG, _args)
#else
struct PRLogModuleInfo;
# define MOZ_LAYERS_LOG(_args)
#endif // if defined(DEBUG) || defined(PR_LOGGING)
class gfxContext;
class nsPaintEvent;
namespace mozilla {
namespace gl {
class GLContext;
}
namespace layers {
class Layer;
class ThebesLayer;
class ContainerLayer;
class ImageLayer;
class ColorLayer;
class ImageContainer;
class CanvasLayer;
class ReadbackLayer;
class ReadbackProcessor;
class ShadowLayer;
class ShadowLayerForwarder;
class ShadowLayerManager;
class SpecificLayerAttributes;
/**
* The viewport and displayport metrics for the painted frame at the
* time of a layer-tree transaction. These metrics are especially
* useful for shadow layers, because the metrics values are updated
* atomically with new pixels.
*/
struct THEBES_API FrameMetrics {
public:
// We use IDs to identify frames across processes.
typedef PRUint64 ViewID;
static const ViewID NULL_SCROLL_ID; // This container layer does not scroll.
static const ViewID ROOT_SCROLL_ID; // This is the root scroll frame.
static const ViewID START_SCROLL_ID; // This is the ID that scrolling subframes
// will begin at.
FrameMetrics()
: mViewport(0, 0, 0, 0)
, mContentSize(0, 0)
, mViewportScrollOffset(0, 0)
, mScrollId(NULL_SCROLL_ID)
{}
// Default copy ctor and operator= are fine
bool operator==(const FrameMetrics& aOther) const
{
return (mViewport.IsEqualEdges(aOther.mViewport) &&
mViewportScrollOffset == aOther.mViewportScrollOffset &&
mDisplayPort.IsEqualEdges(aOther.mDisplayPort) &&
mScrollId == aOther.mScrollId);
}
bool operator!=(const FrameMetrics& aOther) const
{
return !operator==(aOther);
}
bool IsDefault() const
{
return (FrameMetrics() == *this);
}
bool IsRootScrollable() const
{
return mScrollId == ROOT_SCROLL_ID;
}
bool IsScrollable() const
{
return mScrollId != NULL_SCROLL_ID;
}
// These are all in layer coordinate space.
nsIntRect mViewport;
nsIntSize mContentSize;
nsIntPoint mViewportScrollOffset;
nsIntRect mDisplayPort;
ViewID mScrollId;
};
#define MOZ_LAYER_DECL_NAME(n, e) \
virtual const char* Name() const { return n; } \
virtual LayerType GetType() const { return e; }
/**
* Base class for userdata objects attached to layers and layer managers.
*/
class THEBES_API LayerUserData {
public:
virtual ~LayerUserData() {}
};
/*
* Motivation: For truly smooth animation and video playback, we need to
* be able to compose frames and render them on a dedicated thread (i.e.
* off the main thread where DOM manipulation, script execution and layout
* induce difficult-to-bound latency). This requires Gecko to construct
* some kind of persistent scene structure (graph or tree) that can be
* safely transmitted across threads. We have other scenarios (e.g. mobile
* browsing) where retaining some rendered data between paints is desired
* for performance, so again we need a retained scene structure.
*
* Our retained scene structure is a layer tree. Each layer represents
* content which can be composited onto a destination surface; the root
* layer is usually composited into a window, and non-root layers are
* composited into their parent layers. Layers have attributes (e.g.
* opacity and clipping) that influence their compositing.
*
* We want to support a variety of layer implementations, including
* a simple "immediate mode" implementation that doesn't retain any
* rendered data between paints (i.e. uses cairo in just the way that
* Gecko used it before layers were introduced). But we also don't want
* to have bifurcated "layers"/"non-layers" rendering paths in Gecko.
* Therefore the layers API is carefully designed to permit maximally
* efficient implementation in an "immediate mode" style. See the
* BasicLayerManager for such an implementation.
*/
/**
* Helper class to manage user data for layers and LayerManagers.
*/
class THEBES_API LayerUserDataSet {
public:
LayerUserDataSet() : mKey(nsnull) {}
void Set(void* aKey, LayerUserData* aValue)
{
NS_ASSERTION(!mKey || mKey == aKey,
"Multiple LayerUserData objects not supported");
mKey = aKey;
mValue = aValue;
}
/**
* This can be used anytime. Ownership passes to the caller!
*/
LayerUserData* Remove(void* aKey)
{
if (mKey == aKey) {
mKey = nsnull;
LayerUserData* d = mValue.forget();
return d;
}
return nsnull;
}
/**
* This getter can be used anytime.
*/
bool Has(void* aKey)
{
return mKey == aKey;
}
/**
* This getter can be used anytime. Ownership is retained by this object.
*/
LayerUserData* Get(void* aKey)
{
return mKey == aKey ? mValue.get() : nsnull;
}
/**
* Clear out current user data.
*/
void Clear()
{
mKey = nsnull;
mValue = nsnull;
}
private:
void* mKey;
nsAutoPtr<LayerUserData> mValue;
};
/**
* A LayerManager controls a tree of layers. All layers in the tree
* must use the same LayerManager.
*
* All modifications to a layer tree must happen inside a transaction.
* Only the state of the layer tree at the end of a transaction is
* rendered. Transactions cannot be nested
*
* Each transaction has two phases:
* 1) Construction: layers are created, inserted, removed and have
* properties set on them in this phase.
* BeginTransaction and BeginTransactionWithTarget start a transaction in
* the Construction phase. When the client has finished constructing the layer
* tree, it should call EndConstruction() to enter the drawing phase.
* 2) Drawing: ThebesLayers are rendered into in this phase, in tree
* order. When the client has finished drawing into the ThebesLayers, it should
* call EndTransaction to complete the transaction.
*
* All layer API calls happen on the main thread.
*
* Layers are refcounted. The layer manager holds a reference to the
* root layer, and each container layer holds a reference to its children.
*/
class THEBES_API LayerManager {
NS_INLINE_DECL_REFCOUNTING(LayerManager)
public:
enum LayersBackend {
LAYERS_NONE = 0,
LAYERS_BASIC,
LAYERS_OPENGL,
LAYERS_D3D9,
LAYERS_D3D10,
LAYERS_LAST
};
LayerManager() : mDestroyed(false), mSnapEffectiveTransforms(true)
{
InitLog();
}
virtual ~LayerManager() {}
/**
* Release layers and resources held by this layer manager, and mark
* it as destroyed. Should do any cleanup necessary in preparation
* for its widget going away. After this call, only user data calls
* are valid on the layer manager.
*/
virtual void Destroy() { mDestroyed = true; mUserData.Clear(); }
bool IsDestroyed() { return mDestroyed; }
virtual ShadowLayerForwarder* AsShadowForwarder()
{ return nsnull; }
virtual ShadowLayerManager* AsShadowManager()
{ return nsnull; }
/**
* Start a new transaction. Nested transactions are not allowed so
* there must be no transaction currently in progress.
* This transaction will update the state of the window from which
* this LayerManager was obtained.
*/
virtual void BeginTransaction() = 0;
/**
* Start a new transaction. Nested transactions are not allowed so
* there must be no transaction currently in progress.
* This transaction will render the contents of the layer tree to
* the given target context. The rendering will be complete when
* EndTransaction returns.
*/
virtual void BeginTransactionWithTarget(gfxContext* aTarget) = 0;
/**
* Attempts to end an "empty transaction". There must have been no
* changes to the layer tree since the BeginTransaction().
* It's possible for this to fail; ThebesLayers may need to be updated
* due to VRAM data being lost, for example. In such cases this method
* returns false, and the caller must proceed with a normal layer tree
* update and EndTransaction.
*/
virtual bool EndEmptyTransaction() = 0;
/**
* Function called to draw the contents of each ThebesLayer.
* aRegionToDraw contains the region that needs to be drawn.
* This would normally be a subregion of the visible region.
* The callee must draw all of aRegionToDraw. Drawing outside
* aRegionToDraw will be clipped out or ignored.
* The callee must draw all of aRegionToDraw.
* This region is relative to 0,0 in the ThebesLayer.
*
* aRegionToInvalidate contains a region whose contents have been
* changed by the layer manager and which must therefore be invalidated.
* For example, this could be non-empty if a retained layer internally
* switches from RGBA to RGB or back ... we might want to repaint it to
* consistently use subpixel-AA or not.
* This region is relative to 0,0 in the ThebesLayer.
* aRegionToInvalidate may contain areas that are outside
* aRegionToDraw; the callee must ensure that these areas are repainted
* in the current layer manager transaction or in a later layer
* manager transaction.
*
* aContext must not be used after the call has returned.
* We guarantee that buffered contents in the visible
* region are valid once drawing is complete.
*
* The origin of aContext is 0,0 in the ThebesLayer.
*/
typedef void (* DrawThebesLayerCallback)(ThebesLayer* aLayer,
gfxContext* aContext,
const nsIntRegion& aRegionToDraw,
const nsIntRegion& aRegionToInvalidate,
void* aCallbackData);
enum EndTransactionFlags {
END_DEFAULT = 0,
END_NO_IMMEDIATE_REDRAW = 1 << 0 // Do not perform the drawing phase
};
/**
* Finish the construction phase of the transaction, perform the
* drawing phase, and end the transaction.
* During the drawing phase, all ThebesLayers in the tree are
* drawn in tree order, exactly once each, except for those layers
* where it is known that the visible region is empty.
*/
virtual void EndTransaction(DrawThebesLayerCallback aCallback,
void* aCallbackData,
EndTransactionFlags aFlags = END_DEFAULT) = 0;
bool IsSnappingEffectiveTransforms() { return mSnapEffectiveTransforms; }
/**
* CONSTRUCTION PHASE ONLY
* Set the root layer. The root layer is initially null. If there is
* no root layer, EndTransaction won't draw anything.
*/
virtual void SetRoot(Layer* aLayer) = 0;
/**
* Can be called anytime
*/
Layer* GetRoot() { return mRoot; }
/**
* CONSTRUCTION PHASE ONLY
* Called when a managee has mutated.
* Subclasses overriding this method must first call their
* superclass's impl
*/
#ifdef DEBUG
// In debug builds, we check some properties of |aLayer|.
virtual void Mutated(Layer* aLayer);
#else
virtual void Mutated(Layer* aLayer) { }
#endif
/**
* CONSTRUCTION PHASE ONLY
* Create a ThebesLayer for this manager's layer tree.
*/
virtual already_AddRefed<ThebesLayer> CreateThebesLayer() = 0;
/**
* CONSTRUCTION PHASE ONLY
* Create a ContainerLayer for this manager's layer tree.
*/
virtual already_AddRefed<ContainerLayer> CreateContainerLayer() = 0;
/**
* CONSTRUCTION PHASE ONLY
* Create an ImageLayer for this manager's layer tree.
*/
virtual already_AddRefed<ImageLayer> CreateImageLayer() = 0;
/**
* CONSTRUCTION PHASE ONLY
* Create a ColorLayer for this manager's layer tree.
*/
virtual already_AddRefed<ColorLayer> CreateColorLayer() = 0;
/**
* CONSTRUCTION PHASE ONLY
* Create a CanvasLayer for this manager's layer tree.
*/
virtual already_AddRefed<CanvasLayer> CreateCanvasLayer() = 0;
/**
* CONSTRUCTION PHASE ONLY
* Create a ReadbackLayer for this manager's layer tree.
*/
virtual already_AddRefed<ReadbackLayer> CreateReadbackLayer() { return nsnull; }
/**
* Can be called anytime, from any thread.
*/
static already_AddRefed<ImageContainer> CreateImageContainer();
/**
* Type of layer manager his is. This is to be used sparsely in order to
* avoid a lot of Layers backend specific code. It should be used only when
* Layers backend specific functionality is necessary.
*/
virtual LayersBackend GetBackendType() = 0;
/**
* Creates a layer which is optimized for inter-operating with this layer
* manager.
*/
virtual already_AddRefed<gfxASurface>
CreateOptimalSurface(const gfxIntSize &aSize,
gfxASurface::gfxImageFormat imageFormat);
/**
* Creates a DrawTarget which is optimized for inter-operating with this
* layermanager.
*/
virtual TemporaryRef<mozilla::gfx::DrawTarget>
CreateDrawTarget(const mozilla::gfx::IntSize &aSize,
mozilla::gfx::SurfaceFormat aFormat);
virtual bool CanUseCanvasLayerForSize(const gfxIntSize &aSize) { return true; }
/**
* Return the name of the layer manager's backend.
*/
virtual void GetBackendName(nsAString& aName) = 0;
/**
* This setter can be used anytime. The user data for all keys is
* initially null. Ownership pases to the layer manager.
*/
void SetUserData(void* aKey, LayerUserData* aData)
{ mUserData.Set(aKey, aData); }
/**
* This can be used anytime. Ownership passes to the caller!
*/
nsAutoPtr<LayerUserData> RemoveUserData(void* aKey)
{ nsAutoPtr<LayerUserData> d(mUserData.Remove(aKey)); return d; }
/**
* This getter can be used anytime.
*/
bool HasUserData(void* aKey)
{ return mUserData.Has(aKey); }
/**
* This getter can be used anytime. Ownership is retained by the layer
* manager.
*/
LayerUserData* GetUserData(void* aKey)
{ return mUserData.Get(aKey); }
// We always declare the following logging symbols, because it's
// extremely tricky to conditionally declare them. However, for
// ifndef MOZ_LAYERS_HAVE_LOG builds, they only have trivial
// definitions in Layers.cpp.
virtual const char* Name() const { return "???"; }
/**
* Dump information about this layer manager and its managed tree to
* aFile, which defaults to stderr.
*/
void Dump(FILE* aFile=NULL, const char* aPrefix="");
/**
* Dump information about just this layer manager itself to aFile,
* which defaults to stderr.
*/
void DumpSelf(FILE* aFile=NULL, const char* aPrefix="");
/**
* Log information about this layer manager and its managed tree to
* the NSPR log (if enabled for "Layers").
*/
void Log(const char* aPrefix="");
/**
* Log information about just this layer manager itself to the NSPR
* log (if enabled for "Layers").
*/
void LogSelf(const char* aPrefix="");
void StartFrameTimeRecording();
nsTArray<float> StopFrameTimeRecording();
void PostPresent();
static bool IsLogEnabled();
static PRLogModuleInfo* GetLog() { return sLog; }
bool IsCompositingCheap(LayerManager::LayersBackend aBackend)
{ return LAYERS_BASIC != aBackend; }
virtual bool IsCompositingCheap() { return true; }
protected:
nsRefPtr<Layer> mRoot;
LayerUserDataSet mUserData;
bool mDestroyed;
bool mSnapEffectiveTransforms;
// Print interesting information about this into aTo. Internally
// used to implement Dump*() and Log*().
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
static void InitLog();
static PRLogModuleInfo* sLog;
private:
TimeStamp mLastFrameTime;
nsTArray<float> mFrameTimes;
};
class ThebesLayer;
/**
* A Layer represents anything that can be rendered onto a destination
* surface.
*/
class THEBES_API Layer {
NS_INLINE_DECL_REFCOUNTING(Layer)
public:
// Keep these in alphabetical order
enum LayerType {
TYPE_CANVAS,
TYPE_COLOR,
TYPE_CONTAINER,
TYPE_IMAGE,
TYPE_READBACK,
TYPE_SHADOW,
TYPE_THEBES
};
virtual ~Layer() {}
/**
* Returns the LayerManager this Layer belongs to. Note that the layer
* manager might be in a destroyed state, at which point it's only
* valid to set/get user data from it.
*/
LayerManager* Manager() { return mManager; }
enum {
/**
* If this is set, the caller is promising that by the end of this
* transaction the entire visible region (as specified by
* SetVisibleRegion) will be filled with opaque content.
*/
CONTENT_OPAQUE = 0x01,
/**
* If this is set, the caller is notifying that the contents of this layer
* require per-component alpha for optimal fidelity. However, there is no
* guarantee that component alpha will be supported for this layer at
* paint time.
* This should never be set at the same time as CONTENT_OPAQUE.
*/
CONTENT_COMPONENT_ALPHA = 0x02,
/**
* If this is set then this layer is part of a preserve-3d group, and should
* be sorted with sibling layers that are also part of the same group.
*/
CONTENT_PRESERVE_3D = 0x04
};
/**
* CONSTRUCTION PHASE ONLY
* This lets layout make some promises about what will be drawn into the
* visible region of the ThebesLayer. This enables internal quality
* and performance optimizations.
*/
void SetContentFlags(PRUint32 aFlags)
{
NS_ASSERTION((aFlags & (CONTENT_OPAQUE | CONTENT_COMPONENT_ALPHA)) !=
(CONTENT_OPAQUE | CONTENT_COMPONENT_ALPHA),
"Can't be opaque and require component alpha");
mContentFlags = aFlags;
Mutated();
}
/**
* CONSTRUCTION PHASE ONLY
* Tell this layer which region will be visible. The visible region
* is a region which contains all the contents of the layer that can
* actually affect the rendering of the window. It can exclude areas
* that are covered by opaque contents of other layers, and it can
* exclude areas where this layer simply contains no content at all.
* (This can be an overapproximation to the "true" visible region.)
*
* There is no general guarantee that drawing outside the bounds of the
* visible region will be ignored. So if a layer draws outside the bounds
* of its visible region, it needs to ensure that what it draws is valid.
*/
virtual void SetVisibleRegion(const nsIntRegion& aRegion)
{
mVisibleRegion = aRegion;
Mutated();
}
/**
* CONSTRUCTION PHASE ONLY
* Set the opacity which will be applied to this layer as it
* is composited to the destination.
*/
void SetOpacity(float aOpacity)
{
mOpacity = aOpacity;
Mutated();
}
/**
* CONSTRUCTION PHASE ONLY
* Set a clip rect which will be applied to this layer as it is
* composited to the destination. The coordinates are relative to
* the parent layer (i.e. the contents of this layer
* are transformed before this clip rect is applied).
* For the root layer, the coordinates are relative to the widget,
* in device pixels.
* If aRect is null no clipping will be performed.
*/
void SetClipRect(const nsIntRect* aRect)
{
mUseClipRect = aRect != nsnull;
if (aRect) {
mClipRect = *aRect;
}
Mutated();
}
/**
* CONSTRUCTION PHASE ONLY
* Set a clip rect which will be applied to this layer as it is
* composited to the destination. The coordinates are relative to
* the parent layer (i.e. the contents of this layer
* are transformed before this clip rect is applied).
* For the root layer, the coordinates are relative to the widget,
* in device pixels.
* The provided rect is intersected with any existing clip rect.
*/
void IntersectClipRect(const nsIntRect& aRect)
{
if (mUseClipRect) {
mClipRect.IntersectRect(mClipRect, aRect);
} else {
mUseClipRect = true;
mClipRect = aRect;
}
Mutated();
}
/**
* CONSTRUCTION PHASE ONLY
* Tell this layer what its transform should be. The transformation
* is applied when compositing the layer into its parent container.
* XXX Currently only transformations corresponding to 2D affine transforms
* are supported.
*/
void SetTransform(const gfx3DMatrix& aMatrix)
{
mTransform = aMatrix;
Mutated();
}
/**
* CONSTRUCTION PHASE ONLY
*
* Define a subrect of this layer that will be used as the source
* image for tiling this layer's visible region. The coordinates
* are in the un-transformed space of this layer (i.e. the visible
* region of this this layer is tiled before being transformed).
* The visible region is tiled "outwards" from the source rect; that
* is, the source rect is drawn "in place", then repeated to cover
* the layer's visible region.
*
* The interpretation of the source rect varies depending on
* underlying layer type. For ImageLayers and CanvasLayers, it
* doesn't make sense to set a source rect not fully contained by
* the bounds of their underlying images. For ThebesLayers, thebes
* content may need to be rendered to fill the source rect. For
* ColorLayers, a source rect for tiling doesn't make sense at all.
*
* If aRect is null no tiling will be performed.
*
* NB: this interface is only implemented for BasicImageLayers, and
* then only for source rects the same size as the layers'
* underlying images.
*/
void SetTileSourceRect(const nsIntRect* aRect)
{
mUseTileSourceRect = aRect != nsnull;
if (aRect) {
mTileSourceRect = *aRect;
}
Mutated();
}
void SetIsFixedPosition(bool aFixedPosition) { mIsFixedPosition = aFixedPosition; }
// These getters can be used anytime.
float GetOpacity() { return mOpacity; }
const nsIntRect* GetClipRect() { return mUseClipRect ? &mClipRect : nsnull; }
PRUint32 GetContentFlags() { return mContentFlags; }
const nsIntRegion& GetVisibleRegion() { return mVisibleRegion; }
ContainerLayer* GetParent() { return mParent; }
Layer* GetNextSibling() { return mNextSibling; }
Layer* GetPrevSibling() { return mPrevSibling; }
virtual Layer* GetFirstChild() { return nsnull; }
virtual Layer* GetLastChild() { return nsnull; }
const gfx3DMatrix& GetTransform() { return mTransform; }
const nsIntRect* GetTileSourceRect() { return mUseTileSourceRect ? &mTileSourceRect : nsnull; }
bool GetIsFixedPosition() { return mIsFixedPosition; }
/**
* DRAWING PHASE ONLY
*
* Write layer-subtype-specific attributes into aAttrs. Used to
* synchronize layer attributes to their shadows'.
*/
virtual void FillSpecificAttributes(SpecificLayerAttributes& aAttrs) { }
// Returns true if it's OK to save the contents of aLayer in an
// opaque surface (a surface without an alpha channel).
// If we can use a surface without an alpha channel, we should, because
// it will often make painting of antialiased text faster and higher
// quality.
bool CanUseOpaqueSurface();
enum SurfaceMode {
SURFACE_OPAQUE,
SURFACE_SINGLE_CHANNEL_ALPHA,
SURFACE_COMPONENT_ALPHA
};
SurfaceMode GetSurfaceMode()
{
if (CanUseOpaqueSurface())
return SURFACE_OPAQUE;
if (mContentFlags & CONTENT_COMPONENT_ALPHA)
return SURFACE_COMPONENT_ALPHA;
return SURFACE_SINGLE_CHANNEL_ALPHA;
}
/**
* This setter can be used anytime. The user data for all keys is
* initially null. Ownership pases to the layer manager.
*/
void SetUserData(void* aKey, LayerUserData* aData)
{ mUserData.Set(aKey, aData); }
/**
* This can be used anytime. Ownership passes to the caller!
*/
nsAutoPtr<LayerUserData> RemoveUserData(void* aKey)
{ nsAutoPtr<LayerUserData> d(mUserData.Remove(aKey)); return d; }
/**
* This getter can be used anytime.
*/
bool HasUserData(void* aKey)
{ return mUserData.Has(aKey); }
/**
* This getter can be used anytime. Ownership is retained by the layer
* manager.
*/
LayerUserData* GetUserData(void* aKey)
{ return mUserData.Get(aKey); }
/**
* |Disconnect()| is used by layers hooked up over IPC. It may be
* called at any time, and may not be called at all. Using an
* IPC-enabled layer after Destroy() (drawing etc.) results in a
* safe no-op; no crashy or uaf etc.
*
* XXX: this interface is essentially LayerManager::Destroy, but at
* Layer granularity. It might be beneficial to unify them.
*/
virtual void Disconnect() {}
/**
* Dynamic downcast to a Thebes layer. Returns null if this is not
* a ThebesLayer.
*/
virtual ThebesLayer* AsThebesLayer() { return nsnull; }
/**
* Dynamic cast to a ContainerLayer. Returns null if this is not
* a ContainerLayer.
*/
virtual ContainerLayer* AsContainerLayer() { return nsnull; }
/**
* Dynamic cast to a ShadowLayer. Return null if this is not a
* ShadowLayer. Can be used anytime.
*/
virtual ShadowLayer* AsShadowLayer() { return nsnull; }
// These getters can be used anytime. They return the effective
// values that should be used when drawing this layer to screen,
// accounting for this layer possibly being a shadow.
const nsIntRect* GetEffectiveClipRect();
const nsIntRegion& GetEffectiveVisibleRegion();
/**
* Returns the product of the opacities of this layer and all ancestors up
* to and excluding the nearest ancestor that has UseIntermediateSurface() set.
*/
float GetEffectiveOpacity();
/**
* This returns the effective transform computed by
* ComputeEffectiveTransforms. Typically this is a transform that transforms
* this layer all the way to some intermediate surface or destination
* surface. For non-BasicLayers this will be a transform to the nearest
* ancestor with UseIntermediateSurface() (or to the root, if there is no
* such ancestor), but for BasicLayers it's different.
*/
const gfx3DMatrix& GetEffectiveTransform() const { return mEffectiveTransform; }
/**
* @param aTransformToSurface the composition of the transforms
* from the parent layer (if any) to the destination pixel grid.
*
* Computes mEffectiveTransform for this layer and all its descendants.
* mEffectiveTransform transforms this layer up to the destination
* pixel grid (whatever aTransformToSurface is relative to).
*
* We promise that when this is called on a layer, all ancestor layers
* have already had ComputeEffectiveTransforms called.
*/
virtual void ComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface) = 0;
/**
* Calculate the scissor rect required when rendering this layer.
* Returns a rectangle relative to the intermediate surface belonging to the
* nearest ancestor that has an intermediate surface, or relative to the root
* viewport if no ancestor has an intermediate surface, corresponding to the
* clip rect for this layer intersected with aCurrentScissorRect.
* If no ancestor has an intermediate surface, the clip rect is transformed
* by aWorldTransform before being combined with aCurrentScissorRect, if
* aWorldTransform is non-null.
*/
nsIntRect CalculateScissorRect(const nsIntRect& aCurrentScissorRect,
const gfxMatrix* aWorldTransform);
virtual const char* Name() const =0;
virtual LayerType GetType() const =0;
/**
* Only the implementation should call this. This is per-implementation
* private data. Normally, all layers with a given layer manager
* use the same type of ImplData.
*/
void* ImplData() { return mImplData; }
/**
* Only the implementation should use these methods.
*/
void SetParent(ContainerLayer* aParent) { mParent = aParent; }
void SetNextSibling(Layer* aSibling) { mNextSibling = aSibling; }
void SetPrevSibling(Layer* aSibling) { mPrevSibling = aSibling; }
/**
* Dump information about this layer manager and its managed tree to
* aFile, which defaults to stderr.
*/
void Dump(FILE* aFile=NULL, const char* aPrefix="");
/**
* Dump information about just this layer manager itself to aFile,
* which defaults to stderr.
*/
void DumpSelf(FILE* aFile=NULL, const char* aPrefix="");
/**
* Log information about this layer manager and its managed tree to
* the NSPR log (if enabled for "Layers").
*/
void Log(const char* aPrefix="");
/**
* Log information about just this layer manager itself to the NSPR
* log (if enabled for "Layers").
*/
void LogSelf(const char* aPrefix="");
static bool IsLogEnabled() { return LayerManager::IsLogEnabled(); }
protected:
Layer(LayerManager* aManager, void* aImplData) :
mManager(aManager),
mParent(nsnull),
mNextSibling(nsnull),
mPrevSibling(nsnull),
mImplData(aImplData),
mOpacity(1.0),
mContentFlags(0),
mUseClipRect(false),
mUseTileSourceRect(false),
mIsFixedPosition(false)
{}
void Mutated() { mManager->Mutated(this); }
// Print interesting information about this into aTo. Internally
// used to implement Dump*() and Log*(). If subclasses have
// additional interesting properties, they should override this with
// an implementation that first calls the base implementation then
// appends additional info to aTo.
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
/**
* Returns the local transform for this layer: either mTransform or,
* for shadow layers, GetShadowTransform()
*/
const gfx3DMatrix& GetLocalTransform();
/**
* Computes a tweaked version of aTransform that snaps a point or a rectangle
* to pixel boundaries. Snapping is only performed if this layer's
* layer manager has enabled snapping (which is the default).
* @param aSnapRect a rectangle whose edges should be snapped to pixel
* boundaries in the destination surface. If the rectangle is empty,
* then the snapping process should preserve the scale factors of the
* transform matrix
* @param aResidualTransform a transform to apply before mEffectiveTransform
* in order to get the results to completely match aTransform
*/
gfx3DMatrix SnapTransform(const gfx3DMatrix& aTransform,
const gfxRect& aSnapRect,
gfxMatrix* aResidualTransform);
LayerManager* mManager;
ContainerLayer* mParent;
Layer* mNextSibling;
Layer* mPrevSibling;
void* mImplData;
LayerUserDataSet mUserData;
nsIntRegion mVisibleRegion;
gfx3DMatrix mTransform;
gfx3DMatrix mEffectiveTransform;
float mOpacity;
nsIntRect mClipRect;
nsIntRect mTileSourceRect;
PRUint32 mContentFlags;
bool mUseClipRect;
bool mUseTileSourceRect;
bool mIsFixedPosition;
};
/**
* A Layer which we can draw into using Thebes. It is a conceptually
* infinite surface, but each ThebesLayer has an associated "valid region"
* of contents that it is currently storing, which is finite. ThebesLayer
* implementations can store content between paints.
*
* ThebesLayers are rendered into during the drawing phase of a transaction.
*
* Currently the contents of a ThebesLayer are in the device output color
* space.
*/
class THEBES_API ThebesLayer : public Layer {
public:
/**
* CONSTRUCTION PHASE ONLY
* Tell this layer that the content in some region has changed and
* will need to be repainted. This area is removed from the valid
* region.
*/
virtual void InvalidateRegion(const nsIntRegion& aRegion) = 0;
/**
* CONSTRUCTION PHASE ONLY
* Set whether ComputeEffectiveTransforms should compute the
* "residual translation" --- the translation that should be applied *before*
* mEffectiveTransform to get the ideal transform for this ThebesLayer.
* When this is true, ComputeEffectiveTransforms will compute the residual
* and ensure that the layer is invalidated whenever the residual changes.
* When it's false, a change in the residual will not trigger invalidation
* and GetResidualTranslation will return 0,0.
* So when the residual is to be ignored, set this to false for better
* performance.
*/
void SetAllowResidualTranslation(bool aAllow) { mAllowResidualTranslation = aAllow; }
/**
* Can be used anytime
*/
const nsIntRegion& GetValidRegion() const { return mValidRegion; }
virtual ThebesLayer* AsThebesLayer() { return this; }
MOZ_LAYER_DECL_NAME("ThebesLayer", TYPE_THEBES)
virtual void ComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface)
{
// The default implementation just snaps 0,0 to pixels.
gfx3DMatrix idealTransform = GetLocalTransform()*aTransformToSurface;
gfxMatrix residual;
mEffectiveTransform = SnapTransform(idealTransform, gfxRect(0, 0, 0, 0),
mAllowResidualTranslation ? &residual : nsnull);
// The residual can only be a translation because ThebesLayer snapping
// only aligns a single point with the pixel grid; scale factors are always
// preserved exactly
NS_ASSERTION(!residual.HasNonTranslation(),
"Residual transform can only be a translation");
if (residual.GetTranslation() != mResidualTranslation) {
mResidualTranslation = residual.GetTranslation();
NS_ASSERTION(-0.5 <= mResidualTranslation.x && mResidualTranslation.x < 0.5 &&
-0.5 <= mResidualTranslation.y && mResidualTranslation.y < 0.5,
"Residual translation out of range");
mValidRegion.SetEmpty();
}
}
bool UsedForReadback() { return mUsedForReadback; }
void SetUsedForReadback(bool aUsed) { mUsedForReadback = aUsed; }
/**
* Returns the residual translation. Apply this translation when drawing
* into the ThebesLayer so that when mEffectiveTransform is applied afterwards
* by layer compositing, the results exactly match the "ideal transform"
* (the product of the transform of this layer and its ancestors).
* Returns 0,0 unless SetAllowResidualTranslation(true) has been called.
* The residual translation components are always in the range [-0.5, 0.5).
*/
gfxPoint GetResidualTranslation() const { return mResidualTranslation; }
protected:
ThebesLayer(LayerManager* aManager, void* aImplData)
: Layer(aManager, aImplData)
, mValidRegion()
, mUsedForReadback(false)
, mAllowResidualTranslation(false)
{
mContentFlags = 0; // Clear NO_TEXT, NO_TEXT_OVER_TRANSPARENT
}
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
/**
* ComputeEffectiveTransforms snaps the ideal transform to get mEffectiveTransform.
* mResidualTranslation is the translation that should be applied *before*
* mEffectiveTransform to get the ideal transform.
*/
gfxPoint mResidualTranslation;
nsIntRegion mValidRegion;
/**
* Set when this ThebesLayer is participating in readback, i.e. some
* ReadbackLayer (may) be getting its background from this layer.
*/
bool mUsedForReadback;
/**
* True when
*/
bool mAllowResidualTranslation;
};
/**
* A Layer which other layers render into. It holds references to its
* children.
*/
class THEBES_API ContainerLayer : public Layer {
public:
/**
* CONSTRUCTION PHASE ONLY
* Insert aChild into the child list of this container. aChild must
* not be currently in any child list or the root for the layer manager.
* If aAfter is non-null, it must be a child of this container and
* we insert after that layer. If it's null we insert at the start.
*/
virtual void InsertAfter(Layer* aChild, Layer* aAfter) = 0;
/**
* CONSTRUCTION PHASE ONLY
* Remove aChild from the child list of this container. aChild must
* be a child of this container.
*/
virtual void RemoveChild(Layer* aChild) = 0;
/**
* CONSTRUCTION PHASE ONLY
* Set the (sub)document metrics used to render the Layer subtree
* rooted at this.
*/
void SetFrameMetrics(const FrameMetrics& aFrameMetrics)
{
mFrameMetrics = aFrameMetrics;
Mutated();
}
virtual void FillSpecificAttributes(SpecificLayerAttributes& aAttrs);
void SortChildrenBy3DZOrder(nsTArray<Layer*>& aArray);
// These getters can be used anytime.
virtual ContainerLayer* AsContainerLayer() { return this; }
virtual Layer* GetFirstChild() { return mFirstChild; }
virtual Layer* GetLastChild() { return mLastChild; }
const FrameMetrics& GetFrameMetrics() { return mFrameMetrics; }
MOZ_LAYER_DECL_NAME("ContainerLayer", TYPE_CONTAINER)
/**
* ContainerLayer backends need to override ComputeEffectiveTransforms
* since the decision about whether to use a temporary surface for the
* container is backend-specific. ComputeEffectiveTransforms must also set
* mUseIntermediateSurface.
*/
virtual void ComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface) = 0;
/**
* Call this only after ComputeEffectiveTransforms has been invoked
* on this layer.
* Returns true if this will use an intermediate surface. This is largely
* backend-dependent, but it affects the operation of GetEffectiveOpacity().
*/
bool UseIntermediateSurface() { return mUseIntermediateSurface; }
/**
* Returns the rectangle covered by the intermediate surface,
* in this layer's coordinate system
*/
nsIntRect GetIntermediateSurfaceRect()
{
NS_ASSERTION(mUseIntermediateSurface, "Must have intermediate surface");
return mVisibleRegion.GetBounds();
}
/**
* Returns true if this container has more than one non-empty child
*/
bool HasMultipleChildren();
/**
* Returns true if this container supports children with component alpha.
* Should only be called while painting a child of this layer.
*/
bool SupportsComponentAlphaChildren() { return mSupportsComponentAlphaChildren; }
protected:
friend class ReadbackProcessor;
void DidInsertChild(Layer* aLayer);
void DidRemoveChild(Layer* aLayer);
ContainerLayer(LayerManager* aManager, void* aImplData)
: Layer(aManager, aImplData),
mFirstChild(nsnull),
mLastChild(nsnull),
mUseIntermediateSurface(false),
mSupportsComponentAlphaChildren(false),
mMayHaveReadbackChild(false)
{
mContentFlags = 0; // Clear NO_TEXT, NO_TEXT_OVER_TRANSPARENT
}
/**
* A default implementation of ComputeEffectiveTransforms for use by OpenGL
* and D3D.
*/
void DefaultComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface);
/**
* Loops over the children calling ComputeEffectiveTransforms on them.
*/
void ComputeEffectiveTransformsForChildren(const gfx3DMatrix& aTransformToSurface);
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
Layer* mFirstChild;
Layer* mLastChild;
FrameMetrics mFrameMetrics;
bool mUseIntermediateSurface;
bool mSupportsComponentAlphaChildren;
bool mMayHaveReadbackChild;
};
/**
* A Layer which just renders a solid color in its visible region. It actually
* can fill any area that contains the visible region, so if you need to
* restrict the area filled, set a clip region on this layer.
*/
class THEBES_API ColorLayer : public Layer {
public:
/**
* CONSTRUCTION PHASE ONLY
* Set the color of the layer.
*/
virtual void SetColor(const gfxRGBA& aColor)
{
mColor = aColor;
}
// This getter can be used anytime.
virtual const gfxRGBA& GetColor() { return mColor; }
MOZ_LAYER_DECL_NAME("ColorLayer", TYPE_COLOR)
virtual void ComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface)
{
// Snap 0,0 to pixel boundaries, no extra internal transform.
gfx3DMatrix idealTransform = GetLocalTransform()*aTransformToSurface;
mEffectiveTransform = SnapTransform(idealTransform, gfxRect(0, 0, 0, 0), nsnull);
}
protected:
ColorLayer(LayerManager* aManager, void* aImplData)
: Layer(aManager, aImplData),
mColor(0.0, 0.0, 0.0, 0.0)
{}
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
gfxRGBA mColor;
};
/**
* A Layer for HTML Canvas elements. It's backed by either a
* gfxASurface or a GLContext (for WebGL layers), and has some control
* for intelligent updating from the source if necessary (for example,
* if hardware compositing is not available, for reading from the GL
* buffer into an image surface that we can layer composite.)
*
* After Initialize is called, the underlying canvas Surface/GLContext
* must not be modified during a layer transaction.
*/
class THEBES_API CanvasLayer : public Layer {
public:
struct Data {
Data()
: mSurface(nsnull), mGLContext(nsnull)
, mDrawTarget(nsnull), mGLBufferIsPremultiplied(false)
{ }
/* One of these two must be specified, but never both */
gfxASurface* mSurface; // a gfx Surface for the canvas contents
mozilla::gl::GLContext* mGLContext; // a GL PBuffer Context
mozilla::gfx::DrawTarget *mDrawTarget; // a DrawTarget for the canvas contents
/* The size of the canvas content */
nsIntSize mSize;
/* Whether the GLContext contains premultiplied alpha
* values in the framebuffer or not. Defaults to FALSE.
*/
bool mGLBufferIsPremultiplied;
};
/**
* CONSTRUCTION PHASE ONLY
* Initialize this CanvasLayer with the given data. The data must
* have either mSurface or mGLContext initialized (but not both), as
* well as mSize.
*
* This must only be called once.
*/
virtual void Initialize(const Data& aData) = 0;
/**
* Notify this CanvasLayer that the canvas surface contents have
* changed (or will change) before the next transaction.
*/
void Updated() { mDirty = true; }
/**
* Register a callback to be called at the end of each transaction.
*/
typedef void (* DidTransactionCallback)(void* aClosureData);
void SetDidTransactionCallback(DidTransactionCallback aCallback, void* aClosureData)
{
mCallback = aCallback;
mCallbackData = aClosureData;
}
/**
* CONSTRUCTION PHASE ONLY
* Set the filter used to resample this image (if necessary).
*/
void SetFilter(gfxPattern::GraphicsFilter aFilter) { mFilter = aFilter; }
gfxPattern::GraphicsFilter GetFilter() const { return mFilter; }
MOZ_LAYER_DECL_NAME("CanvasLayer", TYPE_CANVAS)
virtual void ComputeEffectiveTransforms(const gfx3DMatrix& aTransformToSurface)
{
// 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(), gfxRect(0, 0, mBounds.width, mBounds.height),
nsnull)*
SnapTransform(aTransformToSurface, gfxRect(0, 0, 0, 0), nsnull);
}
protected:
CanvasLayer(LayerManager* aManager, void* aImplData)
: Layer(aManager, aImplData),
mCallback(nsnull), mCallbackData(nsnull), mFilter(gfxPattern::FILTER_GOOD),
mDirty(false) {}
virtual nsACString& PrintInfo(nsACString& aTo, const char* aPrefix);
void FireDidTransactionCallback()
{
if (mCallback) {
mCallback(mCallbackData);
}
}
/**
* 0, 0, canvaswidth, canvasheight
*/
nsIntRect mBounds;
DidTransactionCallback mCallback;
void* mCallbackData;
gfxPattern::GraphicsFilter mFilter;
/**
* Set to true in Updated(), cleared during a transaction.
*/
bool mDirty;
};
}
}
#endif /* GFX_LAYERS_H */