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Diffstat (limited to 'layout/svg/nsSVGClipPathFrame.h')
| -rw-r--r-- | layout/svg/nsSVGClipPathFrame.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/layout/svg/nsSVGClipPathFrame.h b/layout/svg/nsSVGClipPathFrame.h new file mode 100644 index 0000000000..42a8d16ffd --- /dev/null +++ b/layout/svg/nsSVGClipPathFrame.h @@ -0,0 +1,160 @@ +/* -*- 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 __NS_SVGCLIPPATHFRAME_H__ +#define __NS_SVGCLIPPATHFRAME_H__ + +#include "AutoReferenceLimiter.h" +#include "gfxMatrix.h" +#include "mozilla/Attributes.h" +#include "nsSVGContainerFrame.h" +#include "nsSVGUtils.h" + +class gfxContext; +class nsISVGChildFrame; + +class nsSVGClipPathFrame : public nsSVGContainerFrame +{ + friend nsIFrame* + NS_NewSVGClipPathFrame(nsIPresShell* aPresShell, nsStyleContext* aContext); + + typedef mozilla::gfx::Matrix Matrix; + typedef mozilla::gfx::SourceSurface SourceSurface; + typedef mozilla::image::DrawResult DrawResult; + +protected: + explicit nsSVGClipPathFrame(nsStyleContext* aContext) + : nsSVGContainerFrame(aContext) + , mReferencing(mozilla::AutoReferenceLimiter::notReferencing) + { + AddStateBits(NS_FRAME_IS_NONDISPLAY); + } + +public: + NS_DECL_FRAMEARENA_HELPERS + + // nsIFrame methods: + virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder, + const nsRect& aDirtyRect, + const nsDisplayListSet& aLists) override {} + + // nsSVGClipPathFrame methods: + + /** + * Applies the clipPath by pushing a clip path onto the DrawTarget. + * + * This method must only be used if IsTrivial() returns true, otherwise use + * GetClipMask. + * + * @param aContext The context that the clip path is to be applied to. + * @param aClippedFrame The/an nsIFrame of the element that references this + * clipPath that is currently being processed. + * @param aMatrix The transform from aClippedFrame's user space to aContext's + * current transform. + */ + void ApplyClipPath(gfxContext& aContext, + nsIFrame* aClippedFrame, + const gfxMatrix &aMatrix); + + /** + * Returns an alpha mask surface containing the clipping geometry. + * + * This method must only be used if IsTrivial() returns false, otherwise use + * ApplyClipPath. + * + * @param aReferenceContext Used to determine the backend for and size of the + * returned SourceSurface, the size being limited to the device space clip + * extents on the context. + * @param aClippedFrame The/an nsIFrame of the element that references this + * clipPath that is currently being processed. + * @param aMatrix The transform from aClippedFrame's user space to aContext's + * current transform. + * @param [out] aMaskTransform The transform to use with the returned + * surface. + * @param [in, optional] aExtraMask An extra surface that the returned + * surface should be masked with. + * @param [in, optional] aExtraMasksTransform The transform to use with + * aExtraMask. Should be passed when aExtraMask is passed. + * @param [out, optional] aResult returns the result of drawing action. + */ + already_AddRefed<SourceSurface> + GetClipMask(gfxContext& aReferenceContext, nsIFrame* aClippedFrame, + const gfxMatrix& aMatrix, Matrix* aMaskTransform, + SourceSurface* aExtraMask = nullptr, + const Matrix& aExtraMasksTransform = Matrix(), + DrawResult* aResult = nullptr); + + /** + * aPoint is expected to be in aClippedFrame's SVG user space. + */ + bool PointIsInsideClipPath(nsIFrame* aClippedFrame, const gfxPoint &aPoint); + + // Check if this clipPath is made up of more than one geometry object. + // If so, the clipping API in cairo isn't enough and we need to use + // mask based clipping. + bool IsTrivial(nsISVGChildFrame **aSingleChild = nullptr); + + bool IsValid(); + + // nsIFrame interface: + virtual nsresult AttributeChanged(int32_t aNameSpaceID, + nsIAtom* aAttribute, + int32_t aModType) override; + + virtual void Init(nsIContent* aContent, + nsContainerFrame* aParent, + nsIFrame* aPrevInFlow) override; + + /** + * Get the "type" of the frame + * + * @see nsGkAtoms::svgClipPathFrame + */ + virtual nsIAtom* GetType() const override; + +#ifdef DEBUG_FRAME_DUMP + virtual nsresult GetFrameName(nsAString& aResult) const override + { + return MakeFrameName(NS_LITERAL_STRING("SVGClipPath"), aResult); + } +#endif + + SVGBBox + GetBBoxForClipPathFrame(const SVGBBox &aBBox, const gfxMatrix &aMatrix); + + /** + * If the clipPath element transforms its children due to + * clipPathUnits="objectBoundingBox" being set on it and/or due to the + * 'transform' attribute being set on it, this function returns the resulting + * transform. + */ + gfxMatrix GetClipPathTransform(nsIFrame* aClippedFrame); + +private: + + // nsSVGContainerFrame methods: + virtual gfxMatrix GetCanvasTM() override; + + // Set, during a GetClipMask() call, to the transform that still needs to be + // concatenated to the transform of the DrawTarget that was passed to + // GetClipMask in order to establish the coordinate space that the clipPath + // establishes for its contents (i.e. including applying 'clipPathUnits' and + // any 'transform' attribute set on the clipPath) specifically for clipping + // the frame that was passed to GetClipMask at that moment in time. This is + // set so that if our GetCanvasTM method is called while GetClipMask is + // painting its children, the returned matrix will include the transforms + // that should be used when creating the mask for the frame passed to + // GetClipMask. + // + // Note: The removal of GetCanvasTM is nearly complete, so our GetCanvasTM + // may not even be called soon/any more. + gfxMatrix mMatrixForChildren; + + // Flag used by AutoReferenceLimiter while we're processing an instance of + // this class to protect against (break) reference loops. + int16_t mReferencing; +}; + +#endif |