gecko-dev/layout/svg/nsSVGMaskFrame.h

130 lines
3.7 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 __NS_SVGMASKFRAME_H__
#define __NS_SVGMASKFRAME_H__
#include "mozilla/Attributes.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/RefPtr.h"
#include "gfxPattern.h"
#include "gfxMatrix.h"
#include "nsSVGContainerFrame.h"
#include "nsSVGUtils.h"
class gfxContext;
typedef nsSVGContainerFrame nsSVGMaskFrameBase;
/**
* Byte offsets of channels in a native packed gfxColor or cairo image surface.
*/
#ifdef IS_BIG_ENDIAN
#define GFX_ARGB32_OFFSET_A 0
#define GFX_ARGB32_OFFSET_R 1
#define GFX_ARGB32_OFFSET_G 2
#define GFX_ARGB32_OFFSET_B 3
#else
#define GFX_ARGB32_OFFSET_A 3
#define GFX_ARGB32_OFFSET_R 2
#define GFX_ARGB32_OFFSET_G 1
#define GFX_ARGB32_OFFSET_B 0
#endif
class nsSVGMaskFrame final : public nsSVGMaskFrameBase
{
friend nsIFrame*
NS_NewSVGMaskFrame(nsIPresShell* aPresShell, nsStyleContext* aContext);
typedef mozilla::gfx::Matrix Matrix;
typedef mozilla::gfx::SourceSurface SourceSurface;
protected:
explicit nsSVGMaskFrame(nsStyleContext* aContext)
: nsSVGMaskFrameBase(aContext)
, mInUse(false)
{
AddStateBits(NS_FRAME_IS_NONDISPLAY);
}
public:
NS_DECL_FRAMEARENA_HELPERS
// nsSVGMaskFrame method:
already_AddRefed<SourceSurface>
GetMaskForMaskedFrame(gfxContext* aContext,
nsIFrame* aMaskedFrame,
const gfxMatrix &aMatrix,
float aOpacity,
Matrix* aMaskTransform);
virtual nsresult AttributeChanged(int32_t aNameSpaceID,
nsIAtom* aAttribute,
int32_t aModType) override;
#ifdef DEBUG
virtual void Init(nsIContent* aContent,
nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) override;
#endif
virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists) override {}
/**
* Get the "type" of the frame
*
* @see nsGkAtoms::svgMaskFrame
*/
virtual nsIAtom* GetType() const override;
#ifdef DEBUG_FRAME_DUMP
virtual nsresult GetFrameName(nsAString& aResult) const override
{
return MakeFrameName(NS_LITERAL_STRING("SVGMask"), aResult);
}
#endif
private:
/**
* If the mask element transforms its children due to
* maskContentUnits="objectBoundingBox" being set on it, this function
* returns the resulting transform.
*/
gfxMatrix GetMaskTransform(nsIFrame* aMaskedFrame);
// A helper class to allow us to paint masks safely. The helper
// automatically sets and clears the mInUse flag on the mask frame
// (to prevent nasty reference loops). It's easy to mess this up
// and break things, so this helper makes the code far more robust.
class MOZ_RAII AutoMaskReferencer
{
public:
explicit AutoMaskReferencer(nsSVGMaskFrame *aFrame
MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
: mFrame(aFrame) {
MOZ_GUARD_OBJECT_NOTIFIER_INIT;
NS_ASSERTION(!mFrame->mInUse, "reference loop!");
mFrame->mInUse = true;
}
~AutoMaskReferencer() {
mFrame->mInUse = false;
}
private:
nsSVGMaskFrame *mFrame;
MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
};
gfxMatrix mMatrixForChildren;
// recursion prevention flag
bool mInUse;
// nsSVGContainerFrame methods:
virtual gfxMatrix GetCanvasTM() override;
};
#endif