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Diffstat (limited to '')
| -rw-r--r-- | layout/generic/TextDrawTarget.h | 618 |
1 files changed, 618 insertions, 0 deletions
diff --git a/layout/generic/TextDrawTarget.h b/layout/generic/TextDrawTarget.h new file mode 100644 index 0000000000..fadd7049fb --- /dev/null +++ b/layout/generic/TextDrawTarget.h @@ -0,0 +1,618 @@ +/* -*- 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/. */ + +#ifndef TextDrawTarget_h +#define TextDrawTarget_h + +#include "mozilla/gfx/2D.h" +#include "mozilla/layers/RenderRootStateManager.h" +#include "mozilla/layers/WebRenderLayerManager.h" +#include "mozilla/layers/WebRenderBridgeChild.h" +#include "mozilla/webrender/WebRenderAPI.h" +#include "mozilla/layers/StackingContextHelper.h" +#include "mozilla/layers/IpcResourceUpdateQueue.h" + +namespace mozilla { +namespace layout { + +using namespace gfx; + +// This class is a fake DrawTarget, used to intercept text draw calls, while +// also collecting up the other aspects of text natively. +// +// When using advanced-layers in nsDisplayText's constructor, we construct this +// and run the full painting algorithm with this as the DrawTarget. This is +// done to avoid having to massively refactor gecko's text painting code (which +// has lots of components shared between other rendering algorithms). +// +// In some phases of the painting algorithm, we can grab the relevant values +// and feed them directly into TextDrawTarget. For instance, selections, +// decorations, and shadows are handled in this manner. In those cases we can +// also short-circuit the painting algorithm to save work. +// +// In other phases, the computed values are sufficiently buried in complex +// code that it's best for us to just intercept the final draw calls. This +// is how we handle computing the glyphs of the main text and text-emphasis +// (see our overloaded FillGlyphs implementation). +// +// To be clear: this is a big hack. With time we hope to refactor the codebase +// so that all the elements of text are handled directly by TextDrawTarget, +// which is to say everything is done like we do selections and shadows now. +// This design is a good step for doing this work incrementally. +// +// This is also likely to be a bit buggy (missing or misinterpreted info) +// while we further develop the design. +// +// TextDrawTarget doesn't yet support all features. See mHasUnsupportedFeatures +// for details. +class TextDrawTarget : public DrawTarget { + public: + explicit TextDrawTarget(wr::DisplayListBuilder& aBuilder, + wr::IpcResourceUpdateQueue& aResources, + const layers::StackingContextHelper& aSc, + layers::RenderRootStateManager* aManager, + nsDisplayItem* aItem, nsRect& aBounds, + bool aCallerDoesSaveRestore = false) + : mCallerDoesSaveRestore(aCallerDoesSaveRestore), mBuilder(aBuilder) { + Reinitialize(aResources, aSc, aManager, aItem, aBounds); + } + + // Prevent this from being copied + TextDrawTarget(const TextDrawTarget& src) = delete; + TextDrawTarget& operator=(const TextDrawTarget&) = delete; + + ~TextDrawTarget() { MOZ_ASSERT(mFinished); } + + void Reinitialize(wr::IpcResourceUpdateQueue& aResources, + const layers::StackingContextHelper& aSc, + layers::RenderRootStateManager* aManager, + nsDisplayItem* aItem, nsRect& aBounds) { + mResources = &aResources; + mSc = &aSc; + mManager = aManager; + mHasUnsupportedFeatures = false; + mHasShadows = false; + + SetPermitSubpixelAA(!aItem->IsSubpixelAADisabled()); + + // Compute clip/bounds + auto appUnitsPerDevPixel = + aItem->Frame()->PresContext()->AppUnitsPerDevPixel(); + LayoutDeviceRect layoutBoundsRect = + LayoutDeviceRect::FromAppUnits(aBounds, appUnitsPerDevPixel); + LayoutDeviceRect layoutClipRect = layoutBoundsRect; + mBoundsRect = wr::ToLayoutRect(layoutBoundsRect); + + // Add 1 pixel of dirty area around clip rect to allow us to paint + // antialiased pixels beyond the measured text extents. + layoutClipRect.Inflate(1); + mSize = IntSize::Ceil(layoutClipRect.Width(), layoutClipRect.Height()); + mClipStack.ClearAndRetainStorage(); + mClipStack.AppendElement(layoutClipRect); + + mBackfaceVisible = !aItem->BackfaceIsHidden(); + + if (!mCallerDoesSaveRestore) { + mBuilder.Save(); + } + } + + void FoundUnsupportedFeature() { mHasUnsupportedFeatures = true; } + bool CheckHasUnsupportedFeatures() { + MOZ_ASSERT(mCallerDoesSaveRestore); +#ifdef DEBUG + MOZ_ASSERT(!mFinished); + mFinished = true; +#endif + return mHasUnsupportedFeatures; + } + + bool Finish() { + MOZ_ASSERT(!mCallerDoesSaveRestore); +#ifdef DEBUG + mFinished = true; +#endif + if (mHasUnsupportedFeatures) { + mBuilder.Restore(); + return false; + } + mBuilder.ClearSave(); + return true; + } + + wr::FontInstanceFlags GetWRGlyphFlags() const { return mWRGlyphFlags; } + void SetWRGlyphFlags(wr::FontInstanceFlags aFlags) { mWRGlyphFlags = aFlags; } + + class AutoRestoreWRGlyphFlags { + public: + ~AutoRestoreWRGlyphFlags() { + if (mTarget) { + mTarget->SetWRGlyphFlags(mFlags); + } + } + + void Save(TextDrawTarget* aTarget) { + // This allows for recursive saves, in case the flags need to be modified + // under multiple conditions (i.e. transforms and synthetic italics), + // since the flags will be restored to the first saved value in the + // destructor on scope exit. + if (!mTarget) { + // Only record the first save with the original flags that will be + // restored. + mTarget = aTarget; + mFlags = aTarget->GetWRGlyphFlags(); + } else { + // Ensure that this is actually a recursive save to the same target + MOZ_ASSERT( + mTarget == aTarget, + "Recursive save of WR glyph flags to different TextDrawTargets"); + } + } + + private: + TextDrawTarget* mTarget = nullptr; + wr::FontInstanceFlags mFlags = {0}; + }; + + // This overload just stores the glyphs/font/color. + void FillGlyphs(ScaledFont* aFont, const GlyphBuffer& aBuffer, + const Pattern& aPattern, + const DrawOptions& aOptions) override { + // Make sure we're only given boring color patterns + MOZ_RELEASE_ASSERT(aOptions.mCompositionOp == CompositionOp::OP_OVER); + MOZ_RELEASE_ASSERT(aOptions.mAlpha == 1.0f); + MOZ_RELEASE_ASSERT(aPattern.GetType() == PatternType::COLOR); + + // Make sure the font exists, and can be serialized + MOZ_RELEASE_ASSERT(aFont); + if (!aFont->CanSerialize()) { + FoundUnsupportedFeature(); + return; + } + + auto* colorPat = static_cast<const ColorPattern*>(&aPattern); + auto color = wr::ToColorF(colorPat->mColor); + MOZ_ASSERT(aBuffer.mNumGlyphs); + auto glyphs = Range<const wr::GlyphInstance>( + reinterpret_cast<const wr::GlyphInstance*>(aBuffer.mGlyphs), + aBuffer.mNumGlyphs); + // MSVC won't let us use offsetof on the following directly so we give it a + // name with typedef + typedef std::remove_reference<decltype(aBuffer.mGlyphs[0])>::type GlyphType; + // Compare gfx::Glyph and wr::GlyphInstance to make sure that they are + // structurally equivalent to ensure that our cast above was ok + static_assert( + std::is_same<decltype(aBuffer.mGlyphs[0].mIndex), + decltype(glyphs[0].index)>() && + std::is_same<decltype(aBuffer.mGlyphs[0].mPosition.x), + decltype(glyphs[0].point.x)>() && + std::is_same<decltype(aBuffer.mGlyphs[0].mPosition.y), + decltype(glyphs[0].point.y)>() && + offsetof(GlyphType, mIndex) == offsetof(wr::GlyphInstance, index) && + offsetof(GlyphType, mPosition) == + offsetof(wr::GlyphInstance, point) && + offsetof(decltype(aBuffer.mGlyphs[0].mPosition), x) == + offsetof(decltype(glyphs[0].point), x) && + offsetof(decltype(aBuffer.mGlyphs[0].mPosition), y) == + offsetof(decltype(glyphs[0].point), y) && + std::is_standard_layout< + std::remove_reference<decltype(aBuffer.mGlyphs[0])>>::value && + std::is_standard_layout< + std::remove_reference<decltype(glyphs[0])>>::value && + sizeof(aBuffer.mGlyphs[0]) == sizeof(glyphs[0]) && + sizeof(aBuffer.mGlyphs[0].mPosition) == sizeof(glyphs[0].point), + "glyph buf types don't match"); + + wr::GlyphOptions glyphOptions; + glyphOptions.render_mode = + wr::ToFontRenderMode(aOptions.mAntialiasMode, GetPermitSubpixelAA()); + glyphOptions.flags = mWRGlyphFlags; + + mManager->WrBridge()->PushGlyphs(mBuilder, glyphs, aFont, color, *mSc, + mBoundsRect, ClipRect(), mBackfaceVisible, + &glyphOptions); + } + + void PushClipRect(const Rect& aRect) override { + LayoutDeviceRect rect = LayoutDeviceRect::FromUnknownRect(aRect); + rect = rect.Intersect(mClipStack.LastElement()); + mClipStack.AppendElement(rect); + } + + void PopClip() override { mClipStack.RemoveLastElement(); } + + IntSize GetSize() const override { return mSize; } + + void AppendShadow(const wr::Shadow& aShadow, bool aInflate) { + mBuilder.PushShadow(mBoundsRect, ClipRect(), mBackfaceVisible, aShadow, + aInflate); + mHasShadows = true; + } + + void TerminateShadows() { + if (mHasShadows) { + mBuilder.PopAllShadows(); + mHasShadows = false; + } + } + + void AppendSelectionRect(const LayoutDeviceRect& aRect, + const DeviceColor& aColor) { + auto rect = wr::ToLayoutRect(aRect); + auto color = wr::ToColorF(aColor); + mBuilder.PushRect(rect, ClipRect(), mBackfaceVisible, color); + } + + // This function is basically designed to slide into the decoration drawing + // code of nsCSSRendering with minimum disruption, to minimize the + // chances of implementation drift. As such, it mostly looks like a call + // to a skia-style StrokeLine method: two end-points, with a thickness + // and style. Notably the end-points are *centered* in the block direction, + // even though webrender wants a rect-like representation, where the points + // are on corners. + // + // So we mangle the format here in a single centralized place, where neither + // webrender nor nsCSSRendering has to care about this mismatch. + // + // NOTE: we assume the points are axis-aligned, and aStart should be used + // as the top-left corner of the rect. + void AppendDecoration(const Point& aStart, const Point& aEnd, + const float aThickness, const bool aVertical, + const DeviceColor& aColor, const uint8_t aStyle) { + auto pos = LayoutDevicePoint::FromUnknownPoint(aStart); + LayoutDeviceSize size; + + if (aVertical) { + pos.x -= aThickness / 2; // adjust from center to corner + size = LayoutDeviceSize(aThickness, aEnd.y - aStart.y); + } else { + pos.y -= aThickness / 2; // adjust from center to corner + size = LayoutDeviceSize(aEnd.x - aStart.x, aThickness); + } + + wr::Line decoration; + decoration.bounds = wr::ToLayoutRect(LayoutDeviceRect(pos, size)); + decoration.wavyLineThickness = 0; // dummy value, unused + decoration.color = wr::ToColorF(aColor); + decoration.orientation = aVertical ? wr::LineOrientation::Vertical + : wr::LineOrientation::Horizontal; + + switch (aStyle) { + case NS_STYLE_TEXT_DECORATION_STYLE_SOLID: + decoration.style = wr::LineStyle::Solid; + break; + case NS_STYLE_TEXT_DECORATION_STYLE_DOTTED: + decoration.style = wr::LineStyle::Dotted; + break; + case NS_STYLE_TEXT_DECORATION_STYLE_DASHED: + decoration.style = wr::LineStyle::Dashed; + break; + // Wavy lines should go through AppendWavyDecoration + case NS_STYLE_TEXT_DECORATION_STYLE_WAVY: + // Double lines should be lowered to two solid lines + case NS_STYLE_TEXT_DECORATION_STYLE_DOUBLE: + default: + MOZ_CRASH("TextDrawTarget received unsupported line style"); + } + + mBuilder.PushLine(ClipRect(), mBackfaceVisible, decoration); + } + + // Seperated out from AppendDecoration because Wavy Lines are completely + // different, and trying to merge the concept is more of a mess than it's + // worth. + void AppendWavyDecoration(const Rect& aBounds, const float aThickness, + const bool aVertical, const DeviceColor& aColor) { + wr::Line decoration; + + decoration.bounds = + wr::ToLayoutRect(LayoutDeviceRect::FromUnknownRect(aBounds)); + decoration.wavyLineThickness = aThickness; + decoration.color = wr::ToColorF(aColor); + decoration.orientation = aVertical ? wr::LineOrientation::Vertical + : wr::LineOrientation::Horizontal; + decoration.style = wr::LineStyle::Wavy; + + mBuilder.PushLine(ClipRect(), mBackfaceVisible, decoration); + } + + layers::WebRenderBridgeChild* WrBridge() { return mManager->WrBridge(); } + layers::WebRenderLayerManager* WrLayerManager() { + return mManager->LayerManager(); + } + + Maybe<wr::ImageKey> DefineImage(const IntSize& aSize, uint32_t aStride, + SurfaceFormat aFormat, const uint8_t* aData) { + wr::ImageKey key = mManager->WrBridge()->GetNextImageKey(); + wr::ImageDescriptor desc(aSize, aStride, aFormat); + Range<uint8_t> bytes(const_cast<uint8_t*>(aData), aStride * aSize.height); + if (mResources->AddImage(key, desc, bytes)) { + return Some(key); + } + return Nothing(); + } + + void PushImage(wr::ImageKey aKey, const Rect& aBounds, const Rect& aClip, + wr::ImageRendering aFilter, const wr::ColorF& aColor) { + if (!aClip.Intersects(GeckoClipRect().ToUnknownRect())) { + return; + } + mBuilder.PushImage(wr::ToLayoutRect(aBounds), wr::ToLayoutRect(aClip), true, + aFilter, aKey, true, aColor); + } + + private: + wr::LayoutRect ClipRect() { + return wr::ToLayoutRect(mClipStack.LastElement()); + } + LayoutDeviceRect GeckoClipRect() { return mClipStack.LastElement(); } + // Whether anything unsupported was encountered. This will result in this + // text being emitted as a blob, which means subpixel-AA can't be used and + // that performance will probably be a bit worse. At this point, we've + // properly implemented everything that shows up a lot, so you can assume + // that the remaining things we don't implement are fairly rare. The complete + // set of things that we don't implement are as follows: + // + // * Unserializable Fonts: WR lives across an IPC boundary + // * Text-Combine-Upright Squishing: no one's really bothered to impl it yet + // * Text-Stroke: not a real standard (exists for webcompat) + // * SVG Glyphs: not a real standard (we got overzealous with svg) + // * Color Glyphs (Emoji) With Transparency: requires us to apply transparency + // with a composited layer (a single emoji can be many single-color glyphs) + // + // The transparent colored-glyphs issue is probably the most valuable to fix, + // since ideally it would also result in us fixing transparency for all + // intersecting glyphs (which currently look bad with or without webrender, + // so there's no fallback like with emoji). Specifically, transparency + // looks bad for "cursive" fonts where glyphs overlap at the seams. Since + // this is more common for non-latin scripts (e.g. मनीष), this amounts to us + // treating non-latin scripts poorly... unless they're emoji. Yikes! + bool mHasUnsupportedFeatures = false; + + // The caller promises to call Save/Restore on the builder as needed. + bool mCallerDoesSaveRestore = false; +#ifdef DEBUG + bool mFinished = false; +#endif + + // Whether PopAllShadows needs to be called + bool mHasShadows = false; + + // Things used to push to webrender + wr::DisplayListBuilder& mBuilder; + wr::IpcResourceUpdateQueue* mResources; + const layers::StackingContextHelper* mSc; + layers::RenderRootStateManager* mManager; + + // Computed facts + IntSize mSize; + wr::LayoutRect mBoundsRect; + AutoTArray<LayoutDeviceRect, 3> mClipStack; + bool mBackfaceVisible; + + wr::FontInstanceFlags mWRGlyphFlags = {0}; + + // The rest of this is dummy implementations of DrawTarget's API + public: + DrawTargetType GetType() const override { + return DrawTargetType::SOFTWARE_RASTER; + } + + BackendType GetBackendType() const override { + return BackendType::WEBRENDER_TEXT; + } + + bool IsRecording() const override { return true; } + bool IsCaptureDT() const override { return false; } + + already_AddRefed<SourceSurface> Snapshot() override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<SourceSurface> IntoLuminanceSource( + LuminanceType aLuminanceType, float aOpacity) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + void Flush() override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void DrawCapturedDT(DrawTargetCapture* aCaptureDT, + const Matrix& aTransform) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void DrawSurface(SourceSurface* aSurface, const Rect& aDest, + const Rect& aSource, const DrawSurfaceOptions& aSurfOptions, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void DrawFilter(FilterNode* aNode, const Rect& aSourceRect, + const Point& aDestPoint, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void DrawSurfaceWithShadow(SourceSurface* aSurface, const Point& aDest, + const DeviceColor& aColor, const Point& aOffset, + Float aSigma, CompositionOp aOperator) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void ClearRect(const Rect& aRect) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void CopySurface(SourceSurface* aSurface, const IntRect& aSourceRect, + const IntPoint& aDestination) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void FillRect(const Rect& aRect, const Pattern& aPattern, + const DrawOptions& aOptions = DrawOptions()) override { + MOZ_RELEASE_ASSERT(aPattern.GetType() == PatternType::COLOR); + + if (!aRect.Intersects(GeckoClipRect().ToUnknownRect())) { + return; + } + auto rect = wr::ToLayoutRect(LayoutDeviceRect::FromUnknownRect(aRect)); + auto color = + wr::ToColorF(static_cast<const ColorPattern&>(aPattern).mColor); + mBuilder.PushRect(rect, ClipRect(), mBackfaceVisible, color); + } + + void StrokeRect(const Rect& aRect, const Pattern& aPattern, + const StrokeOptions& aStrokeOptions, + const DrawOptions& aOptions) override { + MOZ_RELEASE_ASSERT(aPattern.GetType() == PatternType::COLOR && + aStrokeOptions.mDashLength == 0); + + wr::LayoutSideOffsets widths = { + aStrokeOptions.mLineWidth, aStrokeOptions.mLineWidth, + aStrokeOptions.mLineWidth, aStrokeOptions.mLineWidth}; + wr::ColorF color = + wr::ToColorF(static_cast<const ColorPattern&>(aPattern).mColor); + wr::BorderSide sides[4] = {{color, wr::BorderStyle::Solid}, + {color, wr::BorderStyle::Solid}, + {color, wr::BorderStyle::Solid}, + {color, wr::BorderStyle::Solid}}; + wr::BorderRadius radius = {{0, 0}, {0, 0}, {0, 0}, {0, 0}}; + LayoutDeviceRect rect = LayoutDeviceRect::FromUnknownRect(aRect); + rect.Inflate(aStrokeOptions.mLineWidth / 2); + if (!rect.Intersects(GeckoClipRect())) { + return; + } + wr::LayoutRect bounds = wr::ToLayoutRect(rect); + mBuilder.PushBorder(bounds, ClipRect(), true, widths, + Range<const wr::BorderSide>(sides, 4), radius); + } + + void StrokeLine(const Point& aStart, const Point& aEnd, + const Pattern& aPattern, const StrokeOptions& aStrokeOptions, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void Stroke(const Path* aPath, const Pattern& aPattern, + const StrokeOptions& aStrokeOptions, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void Fill(const Path* aPath, const Pattern& aPattern, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void StrokeGlyphs(ScaledFont* aFont, const GlyphBuffer& aBuffer, + const Pattern& aPattern, + const StrokeOptions& aStrokeOptions, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void Mask(const Pattern& aSource, const Pattern& aMask, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void MaskSurface(const Pattern& aSource, SourceSurface* aMask, Point aOffset, + const DrawOptions& aOptions) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + bool Draw3DTransformedSurface(SourceSurface* aSurface, + const Matrix4x4& aMatrix) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void PushClip(const Path* aPath) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void PushDeviceSpaceClipRects(const IntRect* aRects, + uint32_t aCount) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } + + void PushLayer(bool aOpaque, Float aOpacity, SourceSurface* aMask, + const Matrix& aMaskTransform, const IntRect& aBounds, + bool aCopyBackground) override { + // Fine to pretend we do this + } + + void PopLayer() override { + // Fine to pretend we do this + } + + already_AddRefed<SourceSurface> CreateSourceSurfaceFromData( + unsigned char* aData, const IntSize& aSize, int32_t aStride, + SurfaceFormat aFormat) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<SourceSurface> OptimizeSourceSurface( + SourceSurface* aSurface) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<SourceSurface> CreateSourceSurfaceFromNativeSurface( + const NativeSurface& aSurface) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<DrawTarget> CreateSimilarDrawTarget( + const IntSize& aSize, SurfaceFormat aFormat) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + bool CanCreateSimilarDrawTarget(const IntSize& aSize, + SurfaceFormat aFormat) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return false; + } + + virtual RefPtr<DrawTarget> CreateClippedDrawTarget( + const Rect& aBounds, SurfaceFormat aFormat) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<PathBuilder> CreatePathBuilder( + FillRule aFillRule) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<FilterNode> CreateFilter(FilterType aType) override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + already_AddRefed<GradientStops> CreateGradientStops( + GradientStop* aStops, uint32_t aNumStops, + ExtendMode aExtendMode) const override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + return nullptr; + } + + void DetachAllSnapshots() override { + MOZ_CRASH("TextDrawTarget: Method shouldn't be called"); + } +}; + +} // namespace layout +} // namespace mozilla + +#endif |