Mypal/gfx/layers/basic/BasicLayers.h

218 lines
8.5 KiB
C++

/* -*- Mode: C++; tab-width: 2; 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 GFX_BASICLAYERS_H
#define GFX_BASICLAYERS_H
#include <stdint.h> // for INT32_MAX, int32_t
#include "Layers.h" // for Layer (ptr only), etc
#include "gfxTypes.h"
#include "gfxContext.h" // for gfxContext
#include "mozilla/Attributes.h" // for override
#include "mozilla/WidgetUtils.h" // for ScreenRotation
#include "mozilla/layers/LayersTypes.h" // for BufferMode, LayersBackend, etc
#include "nsAString.h"
#include "nsCOMPtr.h" // for already_AddRefed
#include "nsISupportsImpl.h" // for gfxContext::AddRef, etc
#include "nsRegion.h" // for nsIntRegion
#include "nscore.h" // for nsAString, etc
class nsIWidget;
namespace mozilla {
namespace layers {
class ImageFactory;
class ImageLayer;
class PaintLayerContext;
class ReadbackLayer;
/**
* This is a cairo/Thebes-only, main-thread-only implementation of layers.
*
* In each transaction, the client sets up the layer tree and then during
* the drawing phase, each PaintedLayer is painted directly into the target
* context (with appropriate clipping and Push/PopGroups performed
* between layers).
*/
class BasicLayerManager final :
public LayerManager
{
public:
enum BasicLayerManagerType {
BLM_WIDGET,
BLM_OFFSCREEN,
BLM_INACTIVE
};
/**
* Construct a BasicLayerManager which will have no default
* target context. SetDefaultTarget or BeginTransactionWithTarget
* must be called for any rendering to happen. PaintedLayers will not
* be retained.
*/
explicit BasicLayerManager(BasicLayerManagerType aType);
/**
* Construct a BasicLayerManager which will have no default
* target context. SetDefaultTarget or BeginTransactionWithTarget
* must be called for any rendering to happen. PaintedLayers will be
* retained; that is, we will try to retain the visible contents of
* PaintedLayers as cairo surfaces. We create PaintedLayer buffers by
* creating similar surfaces to the default target context, or to
* aWidget's GetThebesSurface if there is no default target context, or
* to the passed-in context if there is no widget and no default
* target context.
*
* This does not keep a strong reference to the widget, so the caller
* must ensure that the widget outlives the layer manager or call
* ClearWidget before the widget dies.
*/
explicit BasicLayerManager(nsIWidget* aWidget);
protected:
virtual ~BasicLayerManager();
public:
BasicLayerManager* AsBasicLayerManager() override { return this; }
/**
* Set the default target context that will be used when BeginTransaction
* is called. This can only be called outside a transaction.
*
* aDoubleBuffering can request double-buffering for drawing to the
* default target. When BUFFERED, the layer manager avoids blitting
* temporary results to aContext and then overpainting them with final
* results, by using a temporary buffer when necessary. In BUFFERED
* mode we always completely overwrite the contents of aContext's
* destination surface (within the clip region) using OP_SOURCE.
*/
void SetDefaultTarget(gfxContext* aContext);
virtual void SetDefaultTargetConfiguration(BufferMode aDoubleBuffering, ScreenRotation aRotation);
gfxContext* GetDefaultTarget() { return mDefaultTarget; }
nsIWidget* GetRetainerWidget() { return mWidget; }
void ClearRetainerWidget() { mWidget = nullptr; }
virtual bool IsWidgetLayerManager() override { return mWidget != nullptr; }
virtual bool IsInactiveLayerManager() override { return mType == BLM_INACTIVE; }
virtual bool BeginTransaction() override;
virtual bool BeginTransactionWithTarget(gfxContext* aTarget) override;
virtual bool EndEmptyTransaction(EndTransactionFlags aFlags = END_DEFAULT) override;
virtual void EndTransaction(DrawPaintedLayerCallback aCallback,
void* aCallbackData,
EndTransactionFlags aFlags = END_DEFAULT) override;
virtual bool ShouldAvoidComponentAlphaLayers() override { return IsWidgetLayerManager(); }
void AbortTransaction();
virtual void SetRoot(Layer* aLayer) override;
virtual already_AddRefed<PaintedLayer> CreatePaintedLayer() override;
virtual already_AddRefed<ContainerLayer> CreateContainerLayer() override;
virtual already_AddRefed<ImageLayer> CreateImageLayer() override;
virtual already_AddRefed<CanvasLayer> CreateCanvasLayer() override;
virtual already_AddRefed<ColorLayer> CreateColorLayer() override;
virtual already_AddRefed<ReadbackLayer> CreateReadbackLayer() override;
virtual ImageFactory *GetImageFactory();
virtual LayersBackend GetBackendType() override { return LayersBackend::LAYERS_BASIC; }
virtual void GetBackendName(nsAString& name) override { name.AssignLiteral("Basic"); }
bool InConstruction() { return mPhase == PHASE_CONSTRUCTION; }
#ifdef DEBUG
bool InDrawing() { return mPhase == PHASE_DRAWING; }
bool InForward() { return mPhase == PHASE_FORWARD; }
#endif
bool InTransaction() { return mPhase != PHASE_NONE; }
gfxContext* GetTarget() { return mTarget; }
void SetTarget(gfxContext* aTarget) { mUsingDefaultTarget = false; mTarget = aTarget; }
bool IsRetained() { return mWidget != nullptr; }
virtual const char* Name() const override { return "Basic"; }
// Clear the cached contents of this layer tree.
virtual void ClearCachedResources(Layer* aSubtree = nullptr) override;
void SetTransactionIncomplete() { mTransactionIncomplete = true; }
bool IsTransactionIncomplete() { return mTransactionIncomplete; }
struct PushedGroup
{
PushedGroup() : mFinalTarget(nullptr), mNeedsClipToVisibleRegion(false), mOperator(gfx::CompositionOp::OP_COUNT), mOpacity(0.0f){}
gfxContext* mFinalTarget;
RefPtr<gfxContext> mGroupTarget;
nsIntRegion mVisibleRegion;
bool mNeedsClipToVisibleRegion;
gfx::IntPoint mGroupOffset;
gfx::CompositionOp mOperator;
gfx::Float mOpacity;
RefPtr<gfx::SourceSurface> mMaskSurface;
gfx::Matrix mMaskTransform;
};
// Construct a PushedGroup for a specific layer.
// Return false if it has some errors in PushGroupForLayer(). Then, the
// "aGroupResult" is unavailable for future using.
bool PushGroupForLayer(gfxContext* aContext, Layer* aLayerContext, const nsIntRegion& aRegion, PushedGroup& aGroupResult);
void PopGroupForLayer(PushedGroup& aGroup);
virtual bool IsCompositingCheap() override { return false; }
virtual int32_t GetMaxTextureSize() const override { return INT32_MAX; }
bool CompositorMightResample() { return mCompositorMightResample; }
protected:
enum TransactionPhase {
PHASE_NONE, PHASE_CONSTRUCTION, PHASE_DRAWING, PHASE_FORWARD
};
TransactionPhase mPhase;
// This is the main body of the PaintLayer routine which will if it has
// children, recurse into PaintLayer() otherwise it will paint using the
// underlying Paint() method of the Layer. It will not do both.
void PaintSelfOrChildren(PaintLayerContext& aPaintContext, gfxContext* aGroupTarget);
// Paint the group onto the underlying target. This is used by PaintLayer to
// flush the group to the underlying target.
void FlushGroup(PaintLayerContext& aPaintContext, bool aNeedsClipToVisibleRegion);
// Paints aLayer to mTarget.
void PaintLayer(gfxContext* aTarget,
Layer* aLayer,
DrawPaintedLayerCallback aCallback,
void* aCallbackData);
// Clear the contents of a layer
void ClearLayer(Layer* aLayer);
bool EndTransactionInternal(DrawPaintedLayerCallback aCallback,
void* aCallbackData,
EndTransactionFlags aFlags = END_DEFAULT);
void FlashWidgetUpdateArea(gfxContext* aContext);
// Widget whose surface should be used as the basis for PaintedLayer
// buffers.
nsIWidget* mWidget;
// The default context for BeginTransaction.
RefPtr<gfxContext> mDefaultTarget;
// The context to draw into.
RefPtr<gfxContext> mTarget;
// Image factory we use.
RefPtr<ImageFactory> mFactory;
BufferMode mDoubleBuffering;
BasicLayerManagerType mType;
bool mUsingDefaultTarget;
bool mTransactionIncomplete;
bool mCompositorMightResample;
};
} // namespace layers
} // namespace mozilla
#endif /* GFX_BASICLAYERS_H */