/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
// Main header first:
#include "nsSVGIntegrationUtils.h"
// Keep others in (case-insensitive) order:
#include "gfxDrawable.h"
#include "gfxPrefs.h"
#include "nsCSSAnonBoxes.h"
#include "nsCSSClipPathInstance.h"
#include "nsDisplayList.h"
#include "nsFilterInstance.h"
#include "nsLayoutUtils.h"
#include "gfxContext.h"
#include "nsSVGClipPathFrame.h"
#include "SVGObserverUtils.h"
#include "nsSVGElement.h"
#include "nsSVGFilterPaintCallback.h"
#include "nsSVGMaskFrame.h"
#include "nsSVGPaintServerFrame.h"
#include "nsSVGUtils.h"
#include "FrameLayerBuilder.h"
#include "BasicLayers.h"
#include "mozilla/gfx/Point.h"
#include "nsCSSRendering.h"
#include "mozilla/Unused.h"
#ifdef MOZ_OLD_STYLE
#include "mozilla/GeckoRestyleManager.h"
#endif
using namespace mozilla;
using namespace mozilla::layers;
using namespace mozilla::gfx;
using namespace mozilla::image;
// ----------------------------------------------------------------------
/**
* This class is used to get the pre-effects visual overflow rect of a frame,
* or, in the case of a frame with continuations, to collect the union of the
* pre-effects visual overflow rects of all the continuations. The result is
* relative to the origin (top left corner of the border box) of the frame, or,
* if the frame has continuations, the origin of the _first_ continuation.
*/
class PreEffectsVisualOverflowCollector : public nsLayoutUtils::BoxCallback {
public:
/**
* If the pre-effects visual overflow rect of the frame being examined
* happens to be known, it can be passed in as aCurrentFrame and its
* pre-effects visual overflow rect can be passed in as
* aCurrentFrameOverflowArea. This is just an optimization to save a
* frame property lookup - these arguments are optional.
*/
PreEffectsVisualOverflowCollector(nsIFrame* aFirstContinuation,
nsIFrame* aCurrentFrame,
const nsRect& aCurrentFrameOverflowArea,
bool aInReflow)
: mFirstContinuation(aFirstContinuation),
mCurrentFrame(aCurrentFrame),
mCurrentFrameOverflowArea(aCurrentFrameOverflowArea),
mInReflow(aInReflow) {
NS_ASSERTION(!mFirstContinuation->GetPrevContinuation(),
"We want the first continuation here");
}
virtual void AddBox(nsIFrame* aFrame) override {
nsRect overflow = (aFrame == mCurrentFrame)
? mCurrentFrameOverflowArea
: GetPreEffectsVisualOverflowRect(aFrame, mInReflow);
mResult.UnionRect(mResult,
overflow + aFrame->GetOffsetTo(mFirstContinuation));
}
nsRect GetResult() const { return mResult; }
private:
static nsRect GetPreEffectsVisualOverflowRect(nsIFrame* aFrame,
bool aInReflow) {
nsRect* r = aFrame->GetProperty(nsIFrame::PreEffectsBBoxProperty());
if (r) {
return *r;
}
#ifdef DEBUG
// Having PreTransformOverflowAreasProperty cached means
// GetVisualOverflowRect() will return post-effect rect, which is not what
// we want. This function intentional reports pre-effect rect. But it does
// not matter if there is no SVG effect on this frame, since no effect
// means post-effect rect matches pre-effect rect.
//
// This function may be called during reflow or painting. We should only
// do this check in painting process since the PreEffectsBBoxProperty of
// continuations are not set correctly while reflowing.
if (nsSVGIntegrationUtils::UsingEffectsForFrame(aFrame) && !aInReflow) {
nsOverflowAreas* preTransformOverflows =
aFrame->GetProperty(aFrame->PreTransformOverflowAreasProperty());
MOZ_ASSERT(!preTransformOverflows,
"GetVisualOverflowRect() won't return the pre-effects rect!");
}
#endif
return aFrame->GetVisualOverflowRect();
}
nsIFrame* mFirstContinuation;
nsIFrame* mCurrentFrame;
const nsRect& mCurrentFrameOverflowArea;
nsRect mResult;
bool mInReflow;
};
/**
* Gets the union of the pre-effects visual overflow rects of all of a frame's
* continuations, in "user space".
*/
static nsRect GetPreEffectsVisualOverflowUnion(
nsIFrame* aFirstContinuation, nsIFrame* aCurrentFrame,
const nsRect& aCurrentFramePreEffectsOverflow,
const nsPoint& aFirstContinuationToUserSpace, bool aInReflow) {
NS_ASSERTION(!aFirstContinuation->GetPrevContinuation(),
"Need first continuation here");
PreEffectsVisualOverflowCollector collector(aFirstContinuation, aCurrentFrame,
aCurrentFramePreEffectsOverflow,
aInReflow);
// Compute union of all overflow areas relative to aFirstContinuation:
nsLayoutUtils::GetAllInFlowBoxes(aFirstContinuation, &collector);
// Return the result in user space:
return collector.GetResult() + aFirstContinuationToUserSpace;
}
/**
* Gets the pre-effects visual overflow rect of aCurrentFrame in "user space".
*/
static nsRect GetPreEffectsVisualOverflow(
nsIFrame* aFirstContinuation, nsIFrame* aCurrentFrame,
const nsPoint& aFirstContinuationToUserSpace) {
NS_ASSERTION(!aFirstContinuation->GetPrevContinuation(),
"Need first continuation here");
PreEffectsVisualOverflowCollector collector(aFirstContinuation, nullptr,
nsRect(), false);
// Compute overflow areas of current frame relative to aFirstContinuation:
nsLayoutUtils::AddBoxesForFrame(aCurrentFrame, &collector);
// Return the result in user space:
return collector.GetResult() + aFirstContinuationToUserSpace;
}
bool nsSVGIntegrationUtils::UsingEffectsForFrame(const nsIFrame* aFrame) {
// Even when SVG display lists are disabled, returning true for SVG frames
// does not adversely affect any of our callers. Therefore we don't bother
// checking the SDL prefs here, since we don't know if we're being called for
// painting or hit-testing anyway.
const nsStyleSVGReset* style = aFrame->StyleSVGReset();
return aFrame->StyleEffects()->HasFilters() || style->HasClipPath() ||
style->HasMask();
}
bool nsSVGIntegrationUtils::UsingMaskOrClipPathForFrame(
const nsIFrame* aFrame) {
const nsStyleSVGReset* style = aFrame->StyleSVGReset();
return style->HasClipPath() || style->HasMask();
}
nsPoint nsSVGIntegrationUtils::GetOffsetToBoundingBox(nsIFrame* aFrame) {
if ((aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT)) {
// Do NOT call GetAllInFlowRectsUnion for SVG - it will get the
// covered region relative to the nsSVGOuterSVGFrame, which is absolutely
// not what we want. SVG frames are always in user space, so they have
// no offset adjustment to make.
return nsPoint();
}
// The GetAllInFlowRectsUnion() call gets the union of the frame border-box
// rects over all continuations, relative to the origin (top-left of the
// border box) of its second argument (here, aFrame, the first continuation).
return -nsLayoutUtils::GetAllInFlowRectsUnion(aFrame, aFrame).TopLeft();
}
/* static */ nsSize nsSVGIntegrationUtils::GetContinuationUnionSize(
nsIFrame* aNonSVGFrame) {
NS_ASSERTION(!aNonSVGFrame->IsFrameOfType(nsIFrame::eSVG),
"SVG frames should not get here");
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aNonSVGFrame);
return nsLayoutUtils::GetAllInFlowRectsUnion(firstFrame, firstFrame).Size();
}
/* static */ gfx::Size nsSVGIntegrationUtils::GetSVGCoordContextForNonSVGFrame(
nsIFrame* aNonSVGFrame) {
NS_ASSERTION(!aNonSVGFrame->IsFrameOfType(nsIFrame::eSVG),
"SVG frames should not get here");
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aNonSVGFrame);
nsRect r = nsLayoutUtils::GetAllInFlowRectsUnion(firstFrame, firstFrame);
nsPresContext* presContext = firstFrame->PresContext();
return gfx::Size(presContext->AppUnitsToFloatCSSPixels(r.width),
presContext->AppUnitsToFloatCSSPixels(r.height));
}
gfxRect nsSVGIntegrationUtils::GetSVGBBoxForNonSVGFrame(
nsIFrame* aNonSVGFrame, bool aUnionContinuations) {
// Except for nsSVGOuterSVGFrame, we shouldn't be getting here with SVG
// frames at all. This function is for elements that are laid out using the
// CSS box model rules.
NS_ASSERTION(!(aNonSVGFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT),
"Frames with SVG layout should not get here");
MOZ_ASSERT(!aNonSVGFrame->IsFrameOfType(nsIFrame::eSVG) ||
aNonSVGFrame->IsSVGOuterSVGFrame());
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aNonSVGFrame);
// 'r' is in "user space":
nsRect r =
(aUnionContinuations)
? GetPreEffectsVisualOverflowUnion(firstFrame, nullptr, nsRect(),
GetOffsetToBoundingBox(firstFrame),
false)
: GetPreEffectsVisualOverflow(firstFrame, aNonSVGFrame,
GetOffsetToBoundingBox(firstFrame));
return nsLayoutUtils::RectToGfxRect(
r, aNonSVGFrame->PresContext()->AppUnitsPerCSSPixel());
}
// XXX Since we're called during reflow, this method is broken for frames with
// continuations. When we're called for a frame with continuations, we're
// called for each continuation in turn as it's reflowed. However, it isn't
// until the last continuation is reflowed that this method's
// GetOffsetToBoundingBox() and GetPreEffectsVisualOverflowUnion() calls will
// obtain valid border boxes for all the continuations. As a result, we'll
// end up returning bogus post-filter visual overflow rects for all the prior
// continuations. Unfortunately, by the time the last continuation is
// reflowed, it's too late to go back and set and propagate the overflow
// rects on the previous continuations.
//
// The reason that we need to pass an override bbox to
// GetPreEffectsVisualOverflowUnion rather than just letting it call into our
// GetSVGBBoxForNonSVGFrame method is because we get called by
// ComputeEffectsRect when it has been called with
// aStoreRectProperties set to false. In this case the pre-effects visual
// overflow rect that it has been passed may be different to that stored on
// aFrame, resulting in a different bbox.
//
// XXXjwatt The pre-effects visual overflow rect passed to
// ComputeEffectsRect won't include continuation overflows, so
// for frames with continuation the following filter analysis will likely end
// up being carried out with a bbox created as if the frame didn't have
// continuations.
//
// XXXjwatt Using aPreEffectsOverflowRect to create the bbox isn't really right
// for SVG frames, since for SVG frames the SVG spec defines the bbox to be
// something quite different to the pre-effects visual overflow rect. However,
// we're essentially calculating an invalidation area here, and using the
// pre-effects overflow rect will actually overestimate that area which, while
// being a bit wasteful, isn't otherwise a problem.
//
nsRect nsSVGIntegrationUtils::ComputePostEffectsVisualOverflowRect(
nsIFrame* aFrame, const nsRect& aPreEffectsOverflowRect) {
NS_ASSERTION(!(aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT),
"Don't call this on SVG child frames");
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aFrame);
SVGObserverUtils::EffectProperties effectProperties =
SVGObserverUtils::GetEffectProperties(firstFrame);
if (!effectProperties.HasValidFilter()) {
return aPreEffectsOverflowRect;
}
// Create an override bbox - see comment above:
nsPoint firstFrameToBoundingBox = GetOffsetToBoundingBox(firstFrame);
// overrideBBox is in "user space", in _CSS_ pixels:
// XXX Why are we rounding out to pixel boundaries? We don't do that in
// GetSVGBBoxForNonSVGFrame, and it doesn't appear to be necessary.
gfxRect overrideBBox = nsLayoutUtils::RectToGfxRect(
GetPreEffectsVisualOverflowUnion(firstFrame, aFrame,
aPreEffectsOverflowRect,
firstFrameToBoundingBox, true),
aFrame->PresContext()->AppUnitsPerCSSPixel());
overrideBBox.RoundOut();
nsRect overflowRect =
nsFilterInstance::GetPostFilterBounds(firstFrame, &overrideBBox);
// Return overflowRect relative to aFrame, rather than "user space":
return overflowRect -
(aFrame->GetOffsetTo(firstFrame) + firstFrameToBoundingBox);
}
nsIntRegion nsSVGIntegrationUtils::AdjustInvalidAreaForSVGEffects(
nsIFrame* aFrame, const nsPoint& aToReferenceFrame,
const nsIntRegion& aInvalidRegion) {
if (aInvalidRegion.IsEmpty()) {
return nsIntRect();
}
// Don't bother calling GetEffectProperties; the filter property should
// already have been set up during reflow/ComputeFrameEffectsRect
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aFrame);
nsSVGFilterProperty* prop = SVGObserverUtils::GetFilterProperty(firstFrame);
if (!prop || !prop->IsInObserverLists()) {
return aInvalidRegion;
}
int32_t appUnitsPerDevPixel = aFrame->PresContext()->AppUnitsPerDevPixel();
if (!prop || !prop->ReferencesValidResources()) {
// The frame is either not there or not currently available,
// perhaps because we're in the middle of tearing stuff down.
// Be conservative, return our visual overflow rect relative
// to the reference frame.
nsRect overflow = aFrame->GetVisualOverflowRect() + aToReferenceFrame;
return overflow.ToOutsidePixels(appUnitsPerDevPixel);
}
// Convert aInvalidRegion into bounding box frame space in app units:
nsPoint toBoundingBox =
aFrame->GetOffsetTo(firstFrame) + GetOffsetToBoundingBox(firstFrame);
// The initial rect was relative to the reference frame, so we need to
// remove that offset to get a rect relative to the current frame.
toBoundingBox -= aToReferenceFrame;
nsRegion preEffectsRegion =
aInvalidRegion.ToAppUnits(appUnitsPerDevPixel).MovedBy(toBoundingBox);
// Adjust the dirty area for effects, and shift it back to being relative to
// the reference frame.
nsRegion result =
nsFilterInstance::GetPostFilterDirtyArea(firstFrame, preEffectsRegion)
.MovedBy(-toBoundingBox);
// Return the result, in pixels relative to the reference frame.
return result.ToOutsidePixels(appUnitsPerDevPixel);
}
nsRect nsSVGIntegrationUtils::GetRequiredSourceForInvalidArea(
nsIFrame* aFrame, const nsRect& aDirtyRect) {
// Don't bother calling GetEffectProperties; the filter property should
// already have been set up during reflow/ComputeFrameEffectsRect
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aFrame);
nsSVGFilterProperty* prop = SVGObserverUtils::GetFilterProperty(firstFrame);
if (!prop || !prop->ReferencesValidResources()) {
return aDirtyRect;
}
// Convert aDirtyRect into "user space" in app units:
nsPoint toUserSpace =
aFrame->GetOffsetTo(firstFrame) + GetOffsetToBoundingBox(firstFrame);
nsRect postEffectsRect = aDirtyRect + toUserSpace;
// Return ther result, relative to aFrame, not in user space:
return nsFilterInstance::GetPreFilterNeededArea(firstFrame, postEffectsRect)
.GetBounds() -
toUserSpace;
}
bool nsSVGIntegrationUtils::HitTestFrameForEffects(nsIFrame* aFrame,
const nsPoint& aPt) {
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aFrame);
// Convert aPt to user space:
nsPoint toUserSpace;
if (aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) {
// XXXmstange Isn't this wrong for svg:use and innerSVG frames?
toUserSpace = aFrame->GetPosition();
} else {
toUserSpace =
aFrame->GetOffsetTo(firstFrame) + GetOffsetToBoundingBox(firstFrame);
}
nsPoint pt = aPt + toUserSpace;
gfxPoint userSpacePt =
gfxPoint(pt.x, pt.y) / aFrame->PresContext()->AppUnitsPerCSSPixel();
return nsSVGUtils::HitTestClip(firstFrame, userSpacePt);
}
class RegularFramePaintCallback : public nsSVGFilterPaintCallback {
public:
RegularFramePaintCallback(nsDisplayListBuilder* aBuilder,
LayerManager* aManager,
const gfxPoint& aUserSpaceToFrameSpaceOffset)
: mBuilder(aBuilder),
mLayerManager(aManager),
mUserSpaceToFrameSpaceOffset(aUserSpaceToFrameSpaceOffset) {}
virtual void Paint(gfxContext& aContext, nsIFrame* aTarget,
const gfxMatrix& aTransform, const nsIntRect* aDirtyRect,
imgDrawingParams& aImgParams) override {
BasicLayerManager* basic = mLayerManager->AsBasicLayerManager();
RefPtr<gfxContext> oldCtx = basic->GetTarget();
basic->SetTarget(&aContext);
gfxContextMatrixAutoSaveRestore autoSR(&aContext);
aContext.SetMatrixDouble(aContext.CurrentMatrixDouble().PreTranslate(
-mUserSpaceToFrameSpaceOffset));
mLayerManager->EndTransaction(FrameLayerBuilder::DrawPaintedLayer,
mBuilder);
basic->SetTarget(oldCtx);
}
private:
nsDisplayListBuilder* mBuilder;
LayerManager* mLayerManager;
gfxPoint mUserSpaceToFrameSpaceOffset;
};
typedef nsSVGIntegrationUtils::PaintFramesParams PaintFramesParams;
/**
* Paint css-positioned-mask onto a given target(aMaskDT).
*/
static void PaintMaskSurface(const PaintFramesParams& aParams,
DrawTarget* aMaskDT, float aOpacity,
nsStyleContext* aSC,
const nsTArray<nsSVGMaskFrame*>& aMaskFrames,
const Matrix& aMaskSurfaceMatrix,
const nsPoint& aOffsetToUserSpace) {
MOZ_ASSERT(aMaskFrames.Length() > 0);
MOZ_ASSERT(aMaskDT->GetFormat() == SurfaceFormat::A8);
MOZ_ASSERT(aOpacity == 1.0 || aMaskFrames.Length() == 1);
const nsStyleSVGReset* svgReset = aSC->StyleSVGReset();
gfxMatrix cssPxToDevPxMatrix =
nsSVGUtils::GetCSSPxToDevPxMatrix(aParams.frame);
nsPresContext* presContext = aParams.frame->PresContext();
gfxPoint devPixelOffsetToUserSpace = nsLayoutUtils::PointToGfxPoint(
aOffsetToUserSpace, presContext->AppUnitsPerDevPixel());
RefPtr<gfxContext> maskContext = gfxContext::CreateOrNull(aMaskDT);
MOZ_ASSERT(maskContext);
maskContext->SetMatrix(aMaskSurfaceMatrix);
// Multiple SVG masks interleave with image mask. Paint each layer onto
// aMaskDT one at a time.
for (int i = aMaskFrames.Length() - 1; i >= 0; i--) {
nsSVGMaskFrame* maskFrame = aMaskFrames[i];
CompositionOp compositionOp =
(i == int(aMaskFrames.Length() - 1))
? CompositionOp::OP_OVER
: nsCSSRendering::GetGFXCompositeMode(
svgReset->mMask.mLayers[i].mComposite);
// maskFrame != nullptr means we get a SVG mask.
// maskFrame == nullptr means we get an image mask.
if (maskFrame) {
Matrix svgMaskMatrix;
nsSVGMaskFrame::MaskParams params(
maskContext, aParams.frame, cssPxToDevPxMatrix, aOpacity,
&svgMaskMatrix, svgReset->mMask.mLayers[i].mMaskMode,
aParams.imgParams);
RefPtr<SourceSurface> svgMask = maskFrame->GetMaskForMaskedFrame(params);
if (svgMask) {
gfxContextMatrixAutoSaveRestore matRestore(maskContext);
maskContext->Multiply(ThebesMatrix(svgMaskMatrix));
aMaskDT->MaskSurface(ColorPattern(Color(0.0, 0.0, 0.0, 1.0)), svgMask,
Point(0, 0), DrawOptions(1.0, compositionOp));
}
} else if (svgReset->mMask.mLayers[i].mImage.IsResolved()) {
gfxContextMatrixAutoSaveRestore matRestore(maskContext);
maskContext->Multiply(gfxMatrix::Translation(-devPixelOffsetToUserSpace));
nsCSSRendering::PaintBGParams params =
nsCSSRendering::PaintBGParams::ForSingleLayer(
*presContext, aParams.dirtyRect, aParams.borderArea,
aParams.frame,
aParams.builder->GetBackgroundPaintFlags() |
nsCSSRendering::PAINTBG_MASK_IMAGE,
i, compositionOp, aOpacity);
aParams.imgParams.result &= nsCSSRendering::PaintStyleImageLayerWithSC(
params, *maskContext, aSC, *aParams.frame->StyleBorder());
} else {
aParams.imgParams.result &= ImgDrawResult::NOT_READY;
}
}
}
struct MaskPaintResult {
RefPtr<SourceSurface> maskSurface;
Matrix maskTransform;
bool transparentBlackMask;
bool opacityApplied;
MaskPaintResult() : transparentBlackMask(false), opacityApplied(false) {}
};
static MaskPaintResult CreateAndPaintMaskSurface(
const PaintFramesParams& aParams, float aOpacity, nsStyleContext* aSC,
const nsTArray<nsSVGMaskFrame*>& aMaskFrames,
const nsPoint& aOffsetToUserSpace) {
const nsStyleSVGReset* svgReset = aSC->StyleSVGReset();
MOZ_ASSERT(aMaskFrames.Length() > 0);
MaskPaintResult paintResult;
gfxContext& ctx = aParams.ctx;
// Optimization for single SVG mask.
if (((aMaskFrames.Length() == 1) && aMaskFrames[0])) {
gfxMatrix cssPxToDevPxMatrix =
nsSVGUtils::GetCSSPxToDevPxMatrix(aParams.frame);
paintResult.opacityApplied = true;
nsSVGMaskFrame::MaskParams params(&ctx, aParams.frame, cssPxToDevPxMatrix,
aOpacity, &paintResult.maskTransform,
svgReset->mMask.mLayers[0].mMaskMode,
aParams.imgParams);
paintResult.maskSurface = aMaskFrames[0]->GetMaskForMaskedFrame(params);
if (!paintResult.maskSurface) {
paintResult.transparentBlackMask = true;
}
return paintResult;
}
const IntRect& maskSurfaceRect = aParams.maskRect;
if (maskSurfaceRect.IsEmpty()) {
paintResult.transparentBlackMask = true;
return paintResult;
}
RefPtr<DrawTarget> maskDT = ctx.GetDrawTarget()->CreateSimilarDrawTarget(
maskSurfaceRect.Size(), SurfaceFormat::A8);
if (!maskDT || !maskDT->IsValid()) {
return paintResult;
}
// We can paint mask along with opacity only if
// 1. There is only one mask, or
// 2. No overlap among masks.
// Collision detect in #2 is not that trivial, we only accept #1 here.
paintResult.opacityApplied = (aMaskFrames.Length() == 1);
// Set context's matrix on maskContext, offset by the maskSurfaceRect's
// position. This makes sure that we combine the masks in device space.
Matrix maskSurfaceMatrix =
ctx.CurrentMatrix() * Matrix::Translation(-aParams.maskRect.TopLeft());
PaintMaskSurface(aParams, maskDT, paintResult.opacityApplied ? aOpacity : 1.0,
aSC, aMaskFrames, maskSurfaceMatrix, aOffsetToUserSpace);
if (aParams.imgParams.result != ImgDrawResult::SUCCESS) {
// Now we know the status of mask resource since we used it while painting.
// According to the return value of PaintMaskSurface, we know whether mask
// resource is resolvable or not.
//
// For a HTML doc:
// According to css-masking spec, always create a mask surface when
// we have any item in maskFrame even if all of those items are
// non-resolvable <mask-sources> or <images>.
// Set paintResult.transparentBlackMask as true, the caller should stop
// painting masked content as if this mask is a transparent black one.
// For a SVG doc:
// SVG 1.1 say that if we fail to resolve a mask, we should draw the
// object unmasked.
// Left patinResult.maskSurface empty, the caller should paint all
// masked content as if this mask is an opaque white one(no mask).
paintResult.transparentBlackMask =
!(aParams.frame->GetStateBits() & NS_FRAME_SVG_LAYOUT);
MOZ_ASSERT(!paintResult.maskSurface);
return paintResult;
}
paintResult.maskTransform = maskSurfaceMatrix;
if (!paintResult.maskTransform.Invert()) {
return paintResult;
}
paintResult.maskSurface = maskDT->Snapshot();
return paintResult;
}
static bool ValidateSVGFrame(nsIFrame* aFrame) {
#ifdef DEBUG
NS_ASSERTION(!(aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT) ||
(NS_SVGDisplayListPaintingEnabled() &&
!(aFrame->GetStateBits() & NS_FRAME_IS_NONDISPLAY)),
"Should not use nsSVGIntegrationUtils on this SVG frame");
#endif
bool hasSVGLayout = (aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT);
if (hasSVGLayout) {
#ifdef DEBUG
nsSVGDisplayableFrame* svgFrame = do_QueryFrame(aFrame);
MOZ_ASSERT(svgFrame && aFrame->GetContent()->IsSVGElement(),
"A non-SVG frame carries NS_FRAME_SVG_LAYOUT flag?");
#endif
const nsIContent* content = aFrame->GetContent();
if (!static_cast<const nsSVGElement*>(content)->HasValidDimensions()) {
// The SVG spec says not to draw _anything_
return false;
}
}
return true;
}
struct EffectOffsets {
// The offset between the reference frame and the bounding box of the
// target frame in app unit.
nsPoint offsetToBoundingBox;
// The offset between the reference frame and the bounding box of the
// target frame in app unit.
nsPoint offsetToUserSpace;
// The offset between the reference frame and the bounding box of the
// target frame in device unit.
gfxPoint offsetToUserSpaceInDevPx;
};
static EffectOffsets ComputeEffectOffset(nsIFrame* aFrame,
const PaintFramesParams& aParams) {
EffectOffsets result;
result.offsetToBoundingBox =
aParams.builder->ToReferenceFrame(aFrame) -
nsSVGIntegrationUtils::GetOffsetToBoundingBox(aFrame);
if (!aFrame->IsFrameOfType(nsIFrame::eSVG)) {
/* Snap the offset if the reference frame is not a SVG frame,
* since other frames will be snapped to pixel when rendering. */
result.offsetToBoundingBox =
nsPoint(aFrame->PresContext()->RoundAppUnitsToNearestDevPixels(
result.offsetToBoundingBox.x),
aFrame->PresContext()->RoundAppUnitsToNearestDevPixels(
result.offsetToBoundingBox.y));
}
// After applying only "aOffsetToBoundingBox", aParams.ctx would have its
// origin at the top left corner of frame's bounding box (over all
// continuations).
// However, SVG painting needs the origin to be located at the origin of the
// SVG frame's "user space", i.e. the space in which, for example, the
// frame's BBox lives.
// SVG geometry frames and foreignObject frames apply their own offsets, so
// their position is relative to their user space. So for these frame types,
// if we want aParams.ctx to be in user space, we first need to subtract the
// frame's position so that SVG painting can later add it again and the
// frame is painted in the right place.
gfxPoint toUserSpaceGfx =
nsSVGUtils::FrameSpaceInCSSPxToUserSpaceOffset(aFrame);
nsPoint toUserSpace =
nsPoint(nsPresContext::CSSPixelsToAppUnits(float(toUserSpaceGfx.x)),
nsPresContext::CSSPixelsToAppUnits(float(toUserSpaceGfx.y)));
result.offsetToUserSpace = result.offsetToBoundingBox - toUserSpace;
#ifdef DEBUG
bool hasSVGLayout = (aFrame->GetStateBits() & NS_FRAME_SVG_LAYOUT);
NS_ASSERTION(
hasSVGLayout || result.offsetToBoundingBox == result.offsetToUserSpace,
"For non-SVG frames there shouldn't be any additional offset");
#endif
result.offsetToUserSpaceInDevPx = nsLayoutUtils::PointToGfxPoint(
result.offsetToUserSpace, aFrame->PresContext()->AppUnitsPerDevPixel());
return result;
}
/**
* Setup transform matrix of a gfx context by a specific frame. Move the
* origin of aParams.ctx to the user space of aFrame.
*/
static EffectOffsets MoveContextOriginToUserSpace(
nsIFrame* aFrame, const PaintFramesParams& aParams) {
EffectOffsets offset = ComputeEffectOffset(aFrame, aParams);
aParams.ctx.SetMatrixDouble(aParams.ctx.CurrentMatrixDouble().PreTranslate(
offset.offsetToUserSpaceInDevPx));
return offset;
}
bool nsSVGIntegrationUtils::IsMaskResourceReady(nsIFrame* aFrame) {
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(aFrame);
SVGObserverUtils::EffectProperties effectProperties =
SVGObserverUtils::GetEffectProperties(firstFrame);
nsTArray<nsSVGMaskFrame*> maskFrames = effectProperties.GetMaskFrames();
const nsStyleSVGReset* svgReset = firstFrame->StyleSVGReset();
for (uint32_t i = 0; i < maskFrames.Length(); i++) {
// Refers to a valid SVG mask.
if (maskFrames[i]) {
continue;
}
// Refers to an external resource, which is not ready yet.
if (!svgReset->mMask.mLayers[i].mImage.IsComplete()) {
return false;
}
}
// Either all mask resources are ready, or no mask resource is needed.
return true;
}
class AutoPopGroup {
public:
AutoPopGroup() : mContext(nullptr) {}
~AutoPopGroup() {
if (mContext) {
mContext->PopGroupAndBlend();
}
}
void SetContext(gfxContext* aContext) { mContext = aContext; }
private:
gfxContext* mContext;
};
void nsSVGIntegrationUtils::PaintMask(const PaintFramesParams& aParams) {
nsSVGUtils::MaskUsage maskUsage;
nsSVGUtils::DetermineMaskUsage(aParams.frame, aParams.handleOpacity,
maskUsage);
nsIFrame* frame = aParams.frame;
if (!ValidateSVGFrame(frame)) {
return;
}
gfxContext& ctx = aParams.ctx;
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(frame);
SVGObserverUtils::EffectProperties effectProperties =
SVGObserverUtils::GetEffectProperties(firstFrame);
RefPtr<DrawTarget> maskTarget = ctx.GetDrawTarget();
if (maskUsage.shouldGenerateMaskLayer &&
(maskUsage.shouldGenerateClipMaskLayer ||
maskUsage.shouldApplyClipPath)) {
// We will paint both mask of positioned mask and clip-path into
// maskTarget.
//
// Create one extra draw target for drawing positioned mask, so that we do
// not have to copy the content of maskTarget before painting
// clip-path into it.
maskTarget = maskTarget->CreateSimilarDrawTarget(maskTarget->GetSize(),
SurfaceFormat::A8);
}
nsTArray<nsSVGMaskFrame*> maskFrames = effectProperties.GetMaskFrames();
AutoPopGroup autoPop;
bool shouldPushOpacity =
(maskUsage.opacity != 1.0) && (maskFrames.Length() != 1);
if (shouldPushOpacity) {
ctx.PushGroupForBlendBack(gfxContentType::COLOR_ALPHA, maskUsage.opacity);
autoPop.SetContext(&ctx);
}
gfxContextMatrixAutoSaveRestore matSR;
// Paint clip-path-basic-shape onto ctx
gfxContextAutoSaveRestore basicShapeSR;
if (maskUsage.shouldApplyBasicShape) {
matSR.SetContext(&ctx);
MoveContextOriginToUserSpace(firstFrame, aParams);
basicShapeSR.SetContext(&ctx);
nsCSSClipPathInstance::ApplyBasicShapeClip(ctx, frame);
if (!maskUsage.shouldGenerateMaskLayer) {
// Only have basic-shape clip-path effect. Fill clipped region by
// opaque white.
ctx.SetColor(Color(1.0, 1.0, 1.0, 1.0));
ctx.Fill();
return;
}
}
// Paint mask onto ctx.
if (maskUsage.shouldGenerateMaskLayer) {
matSR.Restore();
matSR.SetContext(&ctx);
EffectOffsets offsets = MoveContextOriginToUserSpace(frame, aParams);
PaintMaskSurface(aParams, maskTarget,
shouldPushOpacity ? 1.0 : maskUsage.opacity,
firstFrame->StyleContext(), maskFrames,
ctx.CurrentMatrix(), offsets.offsetToUserSpace);
}
// Paint clip-path onto ctx.
if (maskUsage.shouldGenerateClipMaskLayer || maskUsage.shouldApplyClipPath) {
matSR.Restore();
matSR.SetContext(&ctx);
MoveContextOriginToUserSpace(firstFrame, aParams);
Matrix clipMaskTransform;
gfxMatrix cssPxToDevPxMatrix = nsSVGUtils::GetCSSPxToDevPxMatrix(frame);
nsSVGClipPathFrame* clipPathFrame = effectProperties.GetClipPathFrame();
RefPtr<SourceSurface> maskSurface =
maskUsage.shouldGenerateMaskLayer ? maskTarget->Snapshot() : nullptr;
clipPathFrame->PaintClipMask(ctx, frame, cssPxToDevPxMatrix,
&clipMaskTransform, maskSurface,
ctx.CurrentMatrix());
}
}
void nsSVGIntegrationUtils::PaintMaskAndClipPath(
const PaintFramesParams& aParams) {
MOZ_ASSERT(UsingMaskOrClipPathForFrame(aParams.frame),
"Should not use this method when no mask or clipPath effect"
"on this frame");
/* SVG defines the following rendering model:
*
* 1. Render geometry
* 2. Apply filter
* 3. Apply clipping, masking, group opacity
*
* We handle #3 here and perform a couple of optimizations:
*
* + Use cairo's clipPath when representable natively (single object
* clip region).
*
* + Merge opacity and masking if both used together.
*/
nsIFrame* frame = aParams.frame;
if (!ValidateSVGFrame(frame)) {
return;
}
nsSVGUtils::MaskUsage maskUsage;
nsSVGUtils::DetermineMaskUsage(aParams.frame, aParams.handleOpacity,
maskUsage);
if (maskUsage.opacity == 0.0f) {
return;
}
gfxContext& context = aParams.ctx;
gfxContextMatrixAutoSaveRestore matrixAutoSaveRestore(&context);
/* Properties are added lazily and may have been removed by a restyle,
so make sure all applicable ones are set again. */
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(frame);
SVGObserverUtils::EffectProperties effectProperties =
SVGObserverUtils::GetEffectProperties(firstFrame);
nsSVGClipPathFrame* clipPathFrame = effectProperties.GetClipPathFrame();
gfxMatrix cssPxToDevPxMatrix = nsSVGUtils::GetCSSPxToDevPxMatrix(frame);
nsTArray<nsSVGMaskFrame*> maskFrames = effectProperties.GetMaskFrames();
bool shouldGenerateMask =
(maskUsage.opacity != 1.0f || maskUsage.shouldGenerateClipMaskLayer ||
maskUsage.shouldGenerateMaskLayer);
bool shouldPushMask = false;
/* Check if we need to do additional operations on this child's
* rendering, which necessitates rendering into another surface. */
if (shouldGenerateMask) {
gfxContextMatrixAutoSaveRestore matSR;
Matrix maskTransform;
RefPtr<SourceSurface> maskSurface;
bool opacityApplied = false;
if (maskUsage.shouldGenerateMaskLayer) {
matSR.SetContext(&context);
// For css-mask, we want to generate a mask for each continuation frame,
// so we setup context matrix by the position of the current frame,
// instead of the first continuation frame.
EffectOffsets offsets = MoveContextOriginToUserSpace(frame, aParams);
MaskPaintResult paintResult = CreateAndPaintMaskSurface(
aParams, maskUsage.opacity, firstFrame->StyleContext(), maskFrames,
offsets.offsetToUserSpace);
if (paintResult.transparentBlackMask) {
return;
}
maskSurface = paintResult.maskSurface;
if (maskSurface) {
shouldPushMask = true;
maskTransform = paintResult.maskTransform;
opacityApplied = paintResult.opacityApplied;
}
}
if (maskUsage.shouldGenerateClipMaskLayer) {
matSR.Restore();
matSR.SetContext(&context);
MoveContextOriginToUserSpace(firstFrame, aParams);
Matrix clipMaskTransform;
RefPtr<SourceSurface> clipMaskSurface = clipPathFrame->GetClipMask(
context, frame, cssPxToDevPxMatrix, &clipMaskTransform, maskSurface,
maskTransform);
if (clipMaskSurface) {
maskSurface = clipMaskSurface;
maskTransform = clipMaskTransform;
} else {
// Either entire surface is clipped out, or gfx buffer allocation
// failure in nsSVGClipPathFrame::GetClipMask.
return;
}
shouldPushMask = true;
}
// opacity != 1.0f.
if (!maskUsage.shouldGenerateClipMaskLayer &&
!maskUsage.shouldGenerateMaskLayer) {
MOZ_ASSERT(maskUsage.opacity != 1.0f);
matSR.SetContext(&context);
MoveContextOriginToUserSpace(firstFrame, aParams);
shouldPushMask = true;
}
if (shouldPushMask) {
if (aParams.layerManager->GetRoot()->GetContentFlags() &
Layer::CONTENT_COMPONENT_ALPHA) {
context.PushGroupAndCopyBackground(
gfxContentType::COLOR_ALPHA,
opacityApplied ? 1.0 : maskUsage.opacity, maskSurface,
maskTransform);
} else {
context.PushGroupForBlendBack(gfxContentType::COLOR_ALPHA,
opacityApplied ? 1.0 : maskUsage.opacity,
maskSurface, maskTransform);
}
}
}
/* If this frame has only a trivial clipPath, set up cairo's clipping now so
* we can just do normal painting and get it clipped appropriately.
*/
if (maskUsage.shouldApplyClipPath || maskUsage.shouldApplyBasicShape) {
gfxContextMatrixAutoSaveRestore matSR(&context);
MoveContextOriginToUserSpace(firstFrame, aParams);
MOZ_ASSERT(!maskUsage.shouldApplyClipPath ||
!maskUsage.shouldApplyBasicShape);
if (maskUsage.shouldApplyClipPath) {
clipPathFrame->ApplyClipPath(context, frame, cssPxToDevPxMatrix);
} else {
nsCSSClipPathInstance::ApplyBasicShapeClip(context, frame);
}
}
/* Paint the child */
context.SetMatrix(matrixAutoSaveRestore.Matrix());
BasicLayerManager* basic = aParams.layerManager->AsBasicLayerManager();
RefPtr<gfxContext> oldCtx = basic->GetTarget();
basic->SetTarget(&context);
aParams.layerManager->EndTransaction(FrameLayerBuilder::DrawPaintedLayer,
aParams.builder);
basic->SetTarget(oldCtx);
if (gfxPrefs::DrawMaskLayer()) {
gfxContextAutoSaveRestore saver(&context);
context.NewPath();
gfxRect drawingRect = nsLayoutUtils::RectToGfxRect(
aParams.borderArea, frame->PresContext()->AppUnitsPerDevPixel());
context.Rectangle(drawingRect, true);
Color overlayColor(0.0f, 0.0f, 0.0f, 0.8f);
if (maskUsage.shouldGenerateMaskLayer) {
overlayColor.r = 1.0f; // red represents css positioned mask.
}
if (maskUsage.shouldApplyClipPath ||
maskUsage.shouldGenerateClipMaskLayer) {
overlayColor.g = 1.0f; // green represents clip-path:<clip-source>.
}
if (maskUsage.shouldApplyBasicShape) {
overlayColor.b = 1.0f; // blue represents
// clip-path:<basic-shape>||<geometry-box>.
}
context.SetColor(overlayColor);
context.Fill();
}
if (maskUsage.shouldApplyClipPath || maskUsage.shouldApplyBasicShape) {
context.PopClip();
}
if (shouldPushMask) {
context.PopGroupAndBlend();
}
}
void nsSVGIntegrationUtils::PaintFilter(const PaintFramesParams& aParams) {
MOZ_ASSERT(!aParams.builder->IsForGenerateGlyphMask(),
"Filter effect is discarded while generating glyph mask.");
MOZ_ASSERT(aParams.frame->StyleEffects()->HasFilters(),
"Should not use this method when no filter effect on this frame");
nsIFrame* frame = aParams.frame;
if (!ValidateSVGFrame(frame)) {
return;
}
float opacity = nsSVGUtils::ComputeOpacity(frame, aParams.handleOpacity);
if (opacity == 0.0f) {
return;
}
/* Properties are added lazily and may have been removed by a restyle,
so make sure all applicable ones are set again. */
nsIFrame* firstFrame =
nsLayoutUtils::FirstContinuationOrIBSplitSibling(frame);
SVGObserverUtils::EffectProperties effectProperties =
SVGObserverUtils::GetEffectProperties(firstFrame);
if (effectProperties.HasInvalidFilter()) {
return;
}
gfxContext& context = aParams.ctx;
gfxContextAutoSaveRestore autoSR(&context);
EffectOffsets offsets = MoveContextOriginToUserSpace(firstFrame, aParams);
if (opacity != 1.0f) {
context.PushGroupForBlendBack(gfxContentType::COLOR_ALPHA, opacity, nullptr,
Matrix());
}
/* Paint the child and apply filters */
RegularFramePaintCallback callback(aParams.builder, aParams.layerManager,
offsets.offsetToUserSpaceInDevPx);
nsRegion dirtyRegion = aParams.dirtyRect - offsets.offsetToBoundingBox;
nsFilterInstance::PaintFilteredFrame(frame, &context, &callback, &dirtyRegion,
aParams.imgParams);
if (opacity != 1.0f) {
context.PopGroupAndBlend();
}
}
class PaintFrameCallback : public gfxDrawingCallback {
public:
PaintFrameCallback(nsIFrame* aFrame, const nsSize aPaintServerSize,
const IntSize aRenderSize, uint32_t aFlags)
: mFrame(aFrame),
mPaintServerSize(aPaintServerSize),
mRenderSize(aRenderSize),
mFlags(aFlags) {}
virtual bool operator()(gfxContext* aContext, const gfxRect& aFillRect,
const SamplingFilter aSamplingFilter,
const gfxMatrix& aTransform) override;
private:
nsIFrame* mFrame;
nsSize mPaintServerSize;
IntSize mRenderSize;
uint32_t mFlags;
};
bool PaintFrameCallback::operator()(gfxContext* aContext,
const gfxRect& aFillRect,
const SamplingFilter aSamplingFilter,
const gfxMatrix& aTransform) {
if (mFrame->GetStateBits() & NS_FRAME_DRAWING_AS_PAINTSERVER) return false;
AutoSetRestorePaintServerState paintServer(mFrame);
aContext->Save();
// Clip to aFillRect so that we don't paint outside.
aContext->NewPath();
aContext->Rectangle(aFillRect);
aContext->Clip();
gfxMatrix invmatrix = aTransform;
if (!invmatrix.Invert()) {
return false;
}
aContext->Multiply(invmatrix);
// nsLayoutUtils::PaintFrame will anchor its painting at mFrame. But we want
// to have it anchored at the top left corner of the bounding box of all of
// mFrame's continuations. So we add a translation transform.
int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
nsPoint offset = nsSVGIntegrationUtils::GetOffsetToBoundingBox(mFrame);
gfxPoint devPxOffset = gfxPoint(offset.x, offset.y) / appUnitsPerDevPixel;
aContext->Multiply(gfxMatrix::Translation(devPxOffset));
gfxSize paintServerSize =
gfxSize(mPaintServerSize.width, mPaintServerSize.height) /
mFrame->PresContext()->AppUnitsPerDevPixel();
// nsLayoutUtils::PaintFrame wants to render with paintServerSize, but we
// want it to render with mRenderSize, so we need to set up a scale transform.
gfxFloat scaleX = mRenderSize.width / paintServerSize.width;
gfxFloat scaleY = mRenderSize.height / paintServerSize.height;
aContext->Multiply(gfxMatrix::Scaling(scaleX, scaleY));
// Draw.
nsRect dirty(-offset.x, -offset.y, mPaintServerSize.width,
mPaintServerSize.height);
using PaintFrameFlags = nsLayoutUtils::PaintFrameFlags;
PaintFrameFlags flags = PaintFrameFlags::PAINT_IN_TRANSFORM;
if (mFlags & nsSVGIntegrationUtils::FLAG_SYNC_DECODE_IMAGES) {
flags |= PaintFrameFlags::PAINT_SYNC_DECODE_IMAGES;
}
nsLayoutUtils::PaintFrame(aContext, mFrame, dirty, NS_RGBA(0, 0, 0, 0),
nsDisplayListBuilderMode::PAINTING, flags);
nsIFrame* currentFrame = mFrame;
while ((currentFrame = currentFrame->GetNextContinuation()) != nullptr) {
offset = currentFrame->GetOffsetToCrossDoc(mFrame);
devPxOffset = gfxPoint(offset.x, offset.y) / appUnitsPerDevPixel;
aContext->Save();
aContext->Multiply(gfxMatrix::Scaling(1 / scaleX, 1 / scaleY));
aContext->Multiply(gfxMatrix::Translation(devPxOffset));
aContext->Multiply(gfxMatrix::Scaling(scaleX, scaleY));
nsLayoutUtils::PaintFrame(aContext, currentFrame, dirty - offset,
NS_RGBA(0, 0, 0, 0),
nsDisplayListBuilderMode::PAINTING, flags);
aContext->Restore();
}
aContext->Restore();
return true;
}
/* static */ already_AddRefed<gfxDrawable>
nsSVGIntegrationUtils::DrawableFromPaintServer(
nsIFrame* aFrame, nsIFrame* aTarget, const nsSize& aPaintServerSize,
const IntSize& aRenderSize, const DrawTarget* aDrawTarget,
const gfxMatrix& aContextMatrix, uint32_t aFlags) {
// aPaintServerSize is the size that would be filled when using
// background-repeat:no-repeat and background-size:auto. For normal background
// images, this would be the intrinsic size of the image; for gradients and
// patterns this would be the whole target frame fill area.
// aRenderSize is what we will be actually filling after accounting for
// background-size.
if (aFrame->IsFrameOfType(nsIFrame::eSVGPaintServer)) {
// aFrame is either a pattern or a gradient. These fill the whole target
// frame by default, so aPaintServerSize is the whole target background fill
// area.
nsSVGPaintServerFrame* server = static_cast<nsSVGPaintServerFrame*>(aFrame);
gfxRect overrideBounds(0, 0, aPaintServerSize.width,
aPaintServerSize.height);
overrideBounds.Scale(1.0 / aFrame->PresContext()->AppUnitsPerDevPixel());
imgDrawingParams imgParams(aFlags);
RefPtr<gfxPattern> pattern = server->GetPaintServerPattern(
aTarget, aDrawTarget, aContextMatrix, &nsStyleSVG::mFill, 1.0,
imgParams, &overrideBounds);
if (!pattern) return nullptr;
// pattern is now set up to fill aPaintServerSize. But we want it to
// fill aRenderSize, so we need to add a scaling transform.
// We couldn't just have set overrideBounds to aRenderSize - it would have
// worked for gradients, but for patterns it would result in a different
// pattern size.
gfxFloat scaleX = overrideBounds.Width() / aRenderSize.width;
gfxFloat scaleY = overrideBounds.Height() / aRenderSize.height;
gfxMatrix scaleMatrix = gfxMatrix::Scaling(scaleX, scaleY);
pattern->SetMatrix(scaleMatrix * pattern->GetMatrix());
RefPtr<gfxDrawable> drawable = new gfxPatternDrawable(pattern, aRenderSize);
return drawable.forget();
}
if (aFrame->IsFrameOfType(nsIFrame::eSVG) &&
!static_cast<nsSVGDisplayableFrame*>(do_QueryFrame(aFrame))) {
MOZ_ASSERT_UNREACHABLE(
"We should prevent painting of unpaintable SVG "
"before we get here");
return nullptr;
}
// We don't want to paint into a surface as long as we don't need to, so we
// set up a drawing callback.
RefPtr<gfxDrawingCallback> cb =
new PaintFrameCallback(aFrame, aPaintServerSize, aRenderSize, aFlags);
RefPtr<gfxDrawable> drawable = new gfxCallbackDrawable(cb, aRenderSize);
return drawable.forget();
}