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Diffstat (limited to '')
| -rw-r--r-- | gfx/thebes/COLRFonts.cpp | 2673 |
1 files changed, 2673 insertions, 0 deletions
diff --git a/gfx/thebes/COLRFonts.cpp b/gfx/thebes/COLRFonts.cpp new file mode 100644 index 0000000000..89ca35661e --- /dev/null +++ b/gfx/thebes/COLRFonts.cpp @@ -0,0 +1,2673 @@ +/* -*- Mode: C++; tab-width: 20; 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/. */ + +#include "COLRFonts.h" +#include "gfxFontUtils.h" +#include "gfxUtils.h" +#include "harfbuzz/hb.h" +#include "harfbuzz/hb-ot.h" +#include "mozilla/gfx/Helpers.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/StaticPrefs_gfx.h" +#include "TextDrawTarget.h" + +#include <limits> + +using namespace mozilla; +using namespace mozilla::gfx; + +namespace { // anonymous namespace for implementation internals + +#pragma pack(1) // ensure no padding is added to the COLR structs + +// Alias bigendian-reading types from gfxFontUtils to names used in the spec. +using int16 = AutoSwap_PRInt16; +using uint16 = AutoSwap_PRUint16; +using int32 = AutoSwap_PRInt32; +using uint32 = AutoSwap_PRUint32; +using FWORD = AutoSwap_PRInt16; +using UFWORD = AutoSwap_PRUint16; +using Offset16 = AutoSwap_PRUint16; +using Offset24 = AutoSwap_PRUint24; +using Offset32 = AutoSwap_PRUint32; + +struct COLRv1Header; +struct ClipList; +struct LayerRecord; +struct BaseGlyphRecord; +struct DeltaSetIndexMap; +struct ItemVariationStore; + +struct COLRHeader { + uint16 version; + uint16 numBaseGlyphRecords; + Offset32 baseGlyphRecordsOffset; + Offset32 layerRecordsOffset; + uint16 numLayerRecords; + + const BaseGlyphRecord* GetBaseGlyphRecords() const { + return reinterpret_cast<const BaseGlyphRecord*>( + reinterpret_cast<const char*>(this) + baseGlyphRecordsOffset); + } + + const LayerRecord* GetLayerRecords() const { + return reinterpret_cast<const LayerRecord*>( + reinterpret_cast<const char*>(this) + layerRecordsOffset); + } + + bool Validate(uint64_t aLength) const; +}; + +struct BaseGlyphPaintRecord { + uint16 glyphID; + Offset32 paintOffset; +}; + +struct BaseGlyphList { + uint32 numBaseGlyphPaintRecords; + // BaseGlyphPaintRecord baseGlyphPaintRecords[numBaseGlyphPaintRecords]; + const BaseGlyphPaintRecord* baseGlyphPaintRecords() const { + return reinterpret_cast<const BaseGlyphPaintRecord*>(this + 1); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +struct LayerList { + uint32 numLayers; + // uint32 paintOffsets[numLayers]; + const uint32* paintOffsets() const { + return reinterpret_cast<const uint32*>(this + 1); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +struct COLRv1Header { + COLRHeader base; + Offset32 baseGlyphListOffset; + Offset32 layerListOffset; + Offset32 clipListOffset; + Offset32 varIndexMapOffset; + Offset32 itemVariationStoreOffset; + + bool Validate(uint64_t aLength) const; + + const BaseGlyphList* baseGlyphList() const { + uint32_t offset = baseGlyphListOffset; + if (!offset) { + return nullptr; + } + const char* ptr = reinterpret_cast<const char*>(this) + offset; + return reinterpret_cast<const struct BaseGlyphList*>(ptr); + } + + const LayerList* layerList() const { + uint32_t offset = layerListOffset; + if (!offset) { + return nullptr; + } + const char* ptr = reinterpret_cast<const char*>(this) + offset; + return reinterpret_cast<const LayerList*>(ptr); + } + + const struct ClipList* clipList() const { + uint32_t offset = clipListOffset; + if (!offset) { + return nullptr; + } + const char* ptr = reinterpret_cast<const char*>(this) + offset; + return reinterpret_cast<const ClipList*>(ptr); + } + + const struct DeltaSetIndexMap* varIndexMap() const { + uint32_t offset = varIndexMapOffset; + if (!offset) { + return nullptr; + } + const char* ptr = reinterpret_cast<const char*>(this) + offset; + return reinterpret_cast<const DeltaSetIndexMap*>(ptr); + } + + const struct ItemVariationStore* itemVariationStore() const { + uint32_t offset = itemVariationStoreOffset; + if (!offset) { + return nullptr; + } + const char* ptr = reinterpret_cast<const char*>(this) + offset; + return reinterpret_cast<const ItemVariationStore*>(ptr); + } + + const BaseGlyphPaintRecord* GetBaseGlyphPaint(uint32_t aGlyphId) const; +}; + +struct PaintState { + union { + const COLRHeader* v0; + const COLRv1Header* v1; + } mHeader; + const sRGBColor* mPalette; + DrawTarget* mDrawTarget; + ScaledFont* mScaledFont; + const int* mCoords; + DrawOptions mDrawOptions; + uint32_t mCOLRLength; + sRGBColor mCurrentColor; + float mFontUnitsToPixels; + uint16_t mNumColors; + uint16_t mCoordCount; + nsTArray<uint32_t>* mVisited; + + const char* COLRv1BaseAddr() const { + return reinterpret_cast<const char*>(mHeader.v1); + } + + DeviceColor GetColor(uint16_t aPaletteIndex, float aAlpha) const; + + // Convert from FUnits (either integer or Fixed 16.16) to device pixels. + template <typename T> + float F2P(T aPixels) const { + return mFontUnitsToPixels * float(aPixels); + } +}; + +DeviceColor PaintState::GetColor(uint16_t aPaletteIndex, float aAlpha) const { + sRGBColor color; + if (aPaletteIndex < mNumColors) { + color = mPalette[uint16_t(aPaletteIndex)]; + } else if (aPaletteIndex == 0xffff) { + color = mCurrentColor; + } else { // Palette index out of range! Return transparent black. + color = sRGBColor(); + } + color.a *= aAlpha; + return ToDeviceColor(color); +} + +static bool DispatchPaint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds /* may be nullptr if unknown */); +static UniquePtr<Pattern> DispatchMakePattern(const PaintState& aState, + uint32_t aOffset); +static Rect DispatchGetBounds(const PaintState& aState, uint32_t aOffset); +static Matrix DispatchGetMatrix(const PaintState& aState, uint32_t aOffset); + +// Variation-data types +struct Fixed { + enum { kFractionBits = 16 }; + operator float() const { + return float(int32_t(value)) / float(1 << kFractionBits); + } + int32_t intRepr() const { return int32_t(value); } + + private: + int32 value; +}; + +struct F2DOT14 { + enum { kFractionBits = 14 }; + operator float() const { + return float(int16_t(value)) / float(1 << kFractionBits); + } + int32_t intRepr() const { return int16_t(value); } + + private: + int16 value; +}; + +// Saturating addition used for variation indexes to avoid wrap-around. +static uint32_t SatAdd(uint32_t a, uint32_t b) { + if (a <= std::numeric_limits<uint32_t>::max() - b) { + return a + b; + } + return std::numeric_limits<uint32_t>::max(); +} + +struct RegionAxisCoordinates { + F2DOT14 startCoord; + F2DOT14 peakCoord; + F2DOT14 endCoord; +}; + +struct VariationRegion { + // RegionAxisCoordinates regionAxes[axisCount]; + const RegionAxisCoordinates* regionAxes() const { + return reinterpret_cast<const RegionAxisCoordinates*>(this); + } +}; + +struct VariationRegionList { + uint16 axisCount; + uint16 regionCount; + // VariationRegion variationRegions[regionCount]; + const char* variationRegionsBase() const { + return reinterpret_cast<const char*>(this + 1); + } + size_t regionSize() const { + return uint16_t(axisCount) * sizeof(RegionAxisCoordinates); + } + const VariationRegion* getRegion(uint16_t i) const { + if (i >= uint16_t(regionCount)) { + return nullptr; + } + return reinterpret_cast<const VariationRegion*>(variationRegionsBase() + + i * regionSize()); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const { + if (variationRegionsBase() - reinterpret_cast<const char*>(aHeader) + + uint16_t(regionCount) * regionSize() > + aLength) { + return false; + } + return true; + } +}; + +struct DeltaSet { + // (int16 and int8) + // *or* + // (int32 and int16) deltaData[regionIndexCount]; +}; + +struct DeltaSetIndexMap { + enum { INNER_INDEX_BIT_COUNT_MASK = 0x0f, MAP_ENTRY_SIZE_MASK = 0x30 }; + uint8_t format; + uint8_t entryFormat; + union { + struct { + uint16 mapCount; + // uint8 mapData[variable]; + } v0; + struct { + uint32 mapCount; + // uint8 mapData[variable]; + } v1; + }; + uint32_t entrySize() const { + return (((entryFormat & MAP_ENTRY_SIZE_MASK) >> 4) + 1); + } + uint32_t map(uint32_t aIndex) const { + uint32_t mapCount; + const uint8_t* mapData; + switch (format) { + case 0: + mapCount = uint32_t(v0.mapCount); + mapData = reinterpret_cast<const uint8_t*>(&v0.mapCount) + + sizeof(v0.mapCount); + break; + case 1: + mapCount = uint32_t(v1.mapCount); + mapData = reinterpret_cast<const uint8_t*>(&v1.mapCount) + + sizeof(v1.mapCount); + break; + default: + // unknown DeltaSetIndexMap format + return aIndex; + } + if (!mapCount) { + return aIndex; + } + if (aIndex >= mapCount) { + aIndex = mapCount - 1; + } + const uint8_t* entryData = mapData + aIndex * entrySize(); + uint32_t entry = 0; + for (uint32_t i = 0; i < entrySize(); ++i) { + entry = (entry << 8) + entryData[i]; + } + uint16_t outerIndex = + entry >> ((entryFormat & INNER_INDEX_BIT_COUNT_MASK) + 1); + uint16_t innerIndex = + entry & ((1 << ((entryFormat & INNER_INDEX_BIT_COUNT_MASK) + 1)) - 1); + return (uint32_t(outerIndex) << 16) + innerIndex; + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +enum EntryFormatMasks { + INNER_INDEX_BIT_COUNT_MASK = 0x0f, + MAP_ENTRY_SIZE_MASK = 0x30 +}; + +struct ItemVariationData { + enum { WORD_DELTA_COUNT_MASK = 0x7FFF, LONG_WORDS = 0x8000 }; + uint16 itemCount; + uint16 wordDeltaCount; + uint16 regionIndexCount; + // uint16 regionIndexes[regionIndexCount]; + const uint16* regionIndexes() const { + return reinterpret_cast<const uint16*>( + reinterpret_cast<const char*>(this + 1)); + } + // DeltaSet deltaSets[itemCount]; + const DeltaSet* deltaSets() const { + return reinterpret_cast<const DeltaSet*>( + reinterpret_cast<const char*>(this + 1) + + uint16_t(regionIndexCount) * sizeof(uint16)); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +struct ItemVariationStore { + uint16 format; + Offset32 variationRegionListOffset; + uint16 itemVariationDataCount; + // Offset32 itemVariationDataOffsets[itemVariationDataCount]; + const Offset32* itemVariationDataOffsets() const { + return reinterpret_cast<const Offset32*>( + reinterpret_cast<const char*>(this + 1)); + } + const VariationRegionList* variationRegionList() const { + return reinterpret_cast<const VariationRegionList*>( + reinterpret_cast<const char*>(this) + variationRegionListOffset); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +static int32_t ApplyVariation(const PaintState& aState, int32_t aValue, + uint32_t aIndex) { + if (aIndex == 0xffffffff) { + return aValue; + } + const auto* store = aState.mHeader.v1->itemVariationStore(); + if (!store || uint16_t(store->format) != 1) { + return aValue; + } + const DeltaSetIndexMap* map = aState.mHeader.v1->varIndexMap(); + uint32_t mappedIndex = map ? map->map(aIndex) : aIndex; + uint16_t outerIndex = mappedIndex >> 16; + uint16_t innerIndex = mappedIndex & 0xffff; + const auto* itemVariationDataOffsets = store->itemVariationDataOffsets(); + if (mappedIndex == 0xffffffff || + outerIndex >= uint16_t(store->itemVariationDataCount) || + !itemVariationDataOffsets[outerIndex]) { + return aValue; + } + const auto* regionList = store->variationRegionList(); + if (outerIndex >= uint16_t(store->itemVariationDataCount)) { + return aValue; + } + const auto* variationData = reinterpret_cast<const ItemVariationData*>( + reinterpret_cast<const char*>(store) + + itemVariationDataOffsets[outerIndex]); + if (innerIndex >= uint16_t(variationData->itemCount)) { + return aValue; + } + const auto* regionIndexes = variationData->regionIndexes(); + uint16_t regionIndexCount = variationData->regionIndexCount; + const DeltaSet* deltaSets = variationData->deltaSets(); + uint16_t wordDeltaCount = variationData->wordDeltaCount; + bool longWords = wordDeltaCount & ItemVariationData::LONG_WORDS; + wordDeltaCount &= ItemVariationData::WORD_DELTA_COUNT_MASK; + uint32_t deltaSetSize = (regionIndexCount + wordDeltaCount) << longWords; + const uint8_t* deltaData = + reinterpret_cast<const uint8_t*>(deltaSets) + deltaSetSize * innerIndex; + uint16_t deltaSize = longWords ? 4 : 2; + int32_t result = aValue; + for (uint16_t i = 0; i < regionIndexCount; ++i, deltaData += deltaSize) { + if (i == wordDeltaCount) { + deltaSize >>= 1; + } + const auto* region = regionList->getRegion(uint16_t(regionIndexes[i])); + if (!region) { + return aValue; + } + // XXX Should we do the calculations here in fixed-point? Check spec. + float scalar = -1.0; + for (uint16_t axisIndex = 0; axisIndex < uint16_t(regionList->axisCount); + ++axisIndex) { + const auto& axis = region->regionAxes()[axisIndex]; + float peak = axis.peakCoord; + if (peak == 0.0) { + // This axis cannot contribute to scalar. + continue; + } + float start = axis.startCoord; + float end = axis.endCoord; + float value = axisIndex < aState.mCoordCount + ? float(aState.mCoords[axisIndex]) / 16384.0f + : 0.0; + if (value < start || value > end) { + // Out of range: this region is not applicable. + scalar = -1.0; + break; + } + if (scalar < 0.0) { + scalar = 1.0; + } + if (value == peak) { + continue; + } + if (value < peak && peak > start) { + scalar *= (value - start) / (peak - start); + } else if (value > peak && peak < end) { + scalar *= (end - value) / (end - peak); + } + } + if (scalar <= 0.0) { + continue; + } + int32_t delta = *reinterpret_cast<const int8_t*>(deltaData); // sign-extend + for (uint16_t j = 1; j < deltaSize; ++j) { + delta = (delta << 8) | deltaData[j]; + } + delta = int32_t(floorf((float(delta) * scalar) + 0.5f)); + result += delta; + } + return result; +}; + +static float ApplyVariation(const PaintState& aState, Fixed aValue, + uint32_t aIndex) { + return float(ApplyVariation(aState, aValue.intRepr(), aIndex)) / + (1 << Fixed::kFractionBits); +} + +static float ApplyVariation(const PaintState& aState, F2DOT14 aValue, + uint32_t aIndex) { + return float(ApplyVariation(aState, aValue.intRepr(), aIndex)) / + (1 << F2DOT14::kFractionBits); +} + +struct ClipBoxFormat1 { + enum { kFormat = 1 }; + uint8_t format; + FWORD xMin; + FWORD yMin; + FWORD xMax; + FWORD yMax; + + Rect GetRect(const PaintState& aState) const { + MOZ_ASSERT(format == kFormat); + int32_t x0 = int16_t(xMin); + int32_t y0 = int16_t(yMin); + int32_t x1 = int16_t(xMax); + int32_t y1 = int16_t(yMax); + // Flip the y-coordinates to map from OpenType to Moz2d space. + return Rect(aState.F2P(x0), -aState.F2P(y1), aState.F2P(x1 - x0), + aState.F2P(y1 - y0)); + } +}; + +struct ClipBoxFormat2 : public ClipBoxFormat1 { + enum { kFormat = 2 }; + uint32 varIndexBase; + + Rect GetRect(const PaintState& aState) const { + MOZ_ASSERT(format == kFormat); + int32_t x0 = ApplyVariation(aState, int16_t(xMin), varIndexBase); + int32_t y0 = ApplyVariation(aState, int16_t(yMin), SatAdd(varIndexBase, 1)); + int32_t x1 = ApplyVariation(aState, int16_t(xMax), SatAdd(varIndexBase, 2)); + int32_t y1 = ApplyVariation(aState, int16_t(yMax), SatAdd(varIndexBase, 3)); + return Rect(aState.F2P(x0), -aState.F2P(y1), aState.F2P(x1 - x0), + aState.F2P(y1 - y0)); + } +}; + +struct Clip { + uint16 startGlyphID; + uint16 endGlyphID; + Offset24 clipBoxOffset; + + Rect GetRect(const PaintState& aState) const { + uint32_t offset = aState.mHeader.v1->clipListOffset + clipBoxOffset; + const auto* box = aState.COLRv1BaseAddr() + offset; + switch (*box) { + case 1: + return reinterpret_cast<const ClipBoxFormat1*>(box)->GetRect(aState); + case 2: + return reinterpret_cast<const ClipBoxFormat2*>(box)->GetRect(aState); + default: + // unknown ClipBoxFormat + break; + } + return Rect(); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +struct ClipList { + uint8_t format; + uint32 numClips; + // Clip clips[numClips] + const Clip* clips() const { return reinterpret_cast<const Clip*>(this + 1); } + const Clip* GetClip(uint32_t aGlyphId) const { + auto compare = [](const void* key, const void* data) -> int { + uint32_t glyphId = (uint32_t)(uintptr_t)key; + const auto* clip = reinterpret_cast<const Clip*>(data); + uint32_t start = uint16_t(clip->startGlyphID); + uint32_t end = uint16_t(clip->endGlyphID); + if (start <= glyphId && end >= glyphId) { + return 0; + } + return start > glyphId ? -1 : 1; + }; + return reinterpret_cast<const Clip*>(bsearch((void*)(uintptr_t)aGlyphId, + clips(), uint32_t(numClips), + sizeof(Clip), compare)); + } + bool Validate(const COLRv1Header* aHeader, uint64_t aLength) const; +}; + +struct LayerRecord { + uint16 glyphId; + uint16 paletteEntryIndex; + + bool Paint(const PaintState& aState, float aAlpha, + const Point& aPoint) const { + Glyph glyph{uint16_t(glyphId), aPoint}; + GlyphBuffer buffer{&glyph, 1}; + aState.mDrawTarget->FillGlyphs( + aState.mScaledFont, buffer, + ColorPattern(aState.GetColor(paletteEntryIndex, aAlpha)), + aState.mDrawOptions); + return true; + } +}; + +struct BaseGlyphRecord { + uint16 glyphId; + uint16 firstLayerIndex; + uint16 numLayers; + + bool Paint(const PaintState& aState, float aAlpha, + const Point& aPoint) const { + uint32_t layerIndex = uint16_t(firstLayerIndex); + uint32_t end = layerIndex + uint16_t(numLayers); + if (end > uint16_t(aState.mHeader.v0->numLayerRecords)) { + MOZ_ASSERT_UNREACHABLE("bad COLRv0 table"); + return false; + } + const auto* layers = aState.mHeader.v0->GetLayerRecords(); + while (layerIndex < end) { + if (!layers[layerIndex].Paint(aState, aAlpha, aPoint)) { + return false; + } + ++layerIndex; + } + return true; + } +}; + +struct ColorStop { + F2DOT14 stopOffset; + uint16 paletteIndex; + F2DOT14 alpha; + + float GetStopOffset(const PaintState& aState) const { return stopOffset; } + uint16_t GetPaletteIndex() const { return paletteIndex; } + float GetAlpha(const PaintState& aState) const { return alpha; } +}; + +struct VarColorStop : public ColorStop { + uint32 varIndexBase; + + float GetStopOffset(const PaintState& aState) const { + return ApplyVariation(aState, stopOffset, varIndexBase); + } + float GetAlpha(const PaintState& aState) const { + return ApplyVariation(aState, alpha, SatAdd(varIndexBase, 1)); + } +}; + +template <typename T> +struct ColorLineT { + enum { EXTEND_PAD = 0, EXTEND_REPEAT = 1, EXTEND_REFLECT = 2 }; + uint8_t extend; + uint16 numStops; + const T* colorStops() const { return reinterpret_cast<const T*>(this + 1); } + + // If the color line has only one stop, return it as a simple ColorPattern. + UniquePtr<Pattern> AsSolidColor(const PaintState& aState) const { + if (uint16_t(numStops) != 1) { + return nullptr; + } + const auto* stop = colorStops(); + return MakeUnique<ColorPattern>( + aState.GetColor(stop->GetPaletteIndex(), stop->GetAlpha(aState))); + } + + // Retrieve the color stops into an array of GradientStop records. The stops + // are normalized to the range [0 .. 1], and the original offsets of the + // first and last stops are returned. + // If aReverse is true, the color line is reversed. + void CollectGradientStops(const PaintState& aState, + nsTArray<GradientStop>& aStops, float* aFirstStop, + float* aLastStop, bool aReverse = false) const { + MOZ_ASSERT(aStops.IsEmpty()); + uint16_t count = numStops; + if (!count) { + return; + } + const auto* stop = colorStops(); + if (reinterpret_cast<const char*>(stop) + count * sizeof(T) > + aState.COLRv1BaseAddr() + aState.mCOLRLength) { + return; + } + aStops.SetCapacity(count); + for (uint16_t i = 0; i < count; ++i, ++stop) { + DeviceColor color = + aState.GetColor(stop->GetPaletteIndex(), stop->GetAlpha(aState)); + aStops.AppendElement(GradientStop{stop->GetStopOffset(aState), color}); + } + if (count == 1) { + *aFirstStop = *aLastStop = aStops[0].offset; + return; + } + aStops.StableSort(nsDefaultComparator<GradientStop, GradientStop>()); + if (aReverse) { + float a = aStops[0].offset; + float b = aStops.LastElement().offset; + aStops.Reverse(); + for (auto& gs : aStops) { + gs.offset = a + b - gs.offset; + } + } + // Normalize stops to the range 0.0 .. 1.0, and return the original + // start & end. + // Note that if all stops are at the same offset, no normalization + // will be done. + *aFirstStop = aStops[0].offset; + *aLastStop = aStops.LastElement().offset; + if ((*aLastStop > *aFirstStop) && + (*aLastStop != 1.0f || *aFirstStop != 0.0f)) { + float f = 1.0f / (*aLastStop - *aFirstStop); + for (auto& gs : aStops) { + gs.offset = (gs.offset - *aFirstStop) * f; + } + } + } + + // Create a gfx::GradientStops representing the given color line stops, + // applying our extend mode. + already_AddRefed<GradientStops> MakeGradientStops( + const PaintState& aState, nsTArray<GradientStop>& aStops) const { + auto mapExtendMode = [](uint8_t aExtend) -> ExtendMode { + switch (aExtend) { + case EXTEND_REPEAT: + return ExtendMode::REPEAT; + case EXTEND_REFLECT: + return ExtendMode::REFLECT; + case EXTEND_PAD: + default: + return ExtendMode::CLAMP; + } + }; + return aState.mDrawTarget->CreateGradientStops( + aStops.Elements(), aStops.Length(), mapExtendMode(extend)); + } + + already_AddRefed<GradientStops> MakeGradientStops( + const PaintState& aState, float* aFirstStop, float* aLastStop, + bool aReverse = false) const { + AutoTArray<GradientStop, 8> stops; + CollectGradientStops(aState, stops, aFirstStop, aLastStop, aReverse); + if (stops.IsEmpty()) { + return nullptr; + } + return MakeGradientStops(aState, stops); + } +}; + +using ColorLine = ColorLineT<ColorStop>; +using VarColorLine = ColorLineT<VarColorStop>; + +// Used to check for cycles in the paint graph, and bail out to avoid infinite +// recursion when traversing the graph in Paint() or GetBoundingRect(). (Only +// PaintColrLayers and PaintColrGlyph can cause cycles; all other paint types +// have only forward references within the table.) +#define IF_CYCLE_RETURN(retval) \ + if (aState.mVisited->Contains(aOffset)) { \ + return retval; \ + } \ + aState.mVisited->AppendElement(aOffset); \ + ScopeExit e([aState]() { aState.mVisited->RemoveLastElement(); }) + +struct PaintColrLayers { + enum { kFormat = 1 }; + uint8_t format; + uint8_t numLayers; + uint32 firstLayerIndex; + + bool Paint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) const { + MOZ_ASSERT(format == kFormat); + IF_CYCLE_RETURN(true); + const auto* layerList = aState.mHeader.v1->layerList(); + if (!layerList) { + return false; + } + if (uint64_t(firstLayerIndex) + numLayers > layerList->numLayers) { + return false; + } + const auto* paintOffsets = layerList->paintOffsets() + firstLayerIndex; + for (uint32_t i = 0; i < numLayers; i++) { + if (!DispatchPaint(aState, + aState.mHeader.v1->layerListOffset + paintOffsets[i], + aBounds)) { + return false; + } + } + return true; + } + + Rect GetBoundingRect(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + IF_CYCLE_RETURN(Rect()); + const auto* layerList = aState.mHeader.v1->layerList(); + if (!layerList) { + return Rect(); + } + if (uint64_t(firstLayerIndex) + numLayers > layerList->numLayers) { + return Rect(); + } + Rect result; + const auto* paintOffsets = layerList->paintOffsets() + firstLayerIndex; + for (uint32_t i = 0; i < numLayers; i++) { + result = result.Union(DispatchGetBounds( + aState, aState.mHeader.v1->layerListOffset + paintOffsets[i])); + } + return result; + } +}; + +struct PaintPatternBase { + bool Paint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) const { + Matrix m = aState.mDrawTarget->GetTransform(); + if (m.Invert()) { + if (auto pattern = DispatchMakePattern(aState, aOffset)) { + aState.mDrawTarget->FillRect( + m.TransformBounds(IntRectToRect(aState.mDrawTarget->GetRect())), + *pattern, aState.mDrawOptions); + return true; + } + } + return false; + } + + Rect GetBoundingRect(const PaintState& aState, uint32_t aOffset) const { + return Rect(); + } +}; + +struct PaintSolid : public PaintPatternBase { + enum { kFormat = 2 }; + uint8_t format; + uint16 paletteIndex; + F2DOT14 alpha; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return MakeUnique<ColorPattern>(aState.GetColor(paletteIndex, alpha)); + } +}; + +struct PaintVarSolid : public PaintSolid { + enum { kFormat = 3 }; + uint32 varIndexBase; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return MakeUnique<ColorPattern>(aState.GetColor( + paletteIndex, ApplyVariation(aState, alpha, varIndexBase))); + } +}; + +struct PaintLinearGradient : public PaintPatternBase { + enum { kFormat = 4 }; + uint8_t format; + Offset24 colorLineOffset; + FWORD x0; + FWORD y0; + FWORD x1; + FWORD y1; + FWORD x2; + FWORD y2; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + uint32_t clOffset = aOffset + colorLineOffset; + if (clOffset + sizeof(ColorLine) + sizeof(ColorStop) > aState.mCOLRLength) { + return nullptr; + } + const auto* colorLine = + reinterpret_cast<const ColorLine*>(aState.COLRv1BaseAddr() + clOffset); + Point p0(aState.F2P(int16_t(x0)), aState.F2P(int16_t(y0))); + Point p1(aState.F2P(int16_t(x1)), aState.F2P(int16_t(y1))); + Point p2(aState.F2P(int16_t(x2)), aState.F2P(int16_t(y2))); + return NormalizeAndMakeGradient(aState, colorLine, p0, p1, p2); + } + + template <typename T> + UniquePtr<Pattern> NormalizeAndMakeGradient(const PaintState& aState, + const T* aColorLine, Point p0, + Point p1, Point p2) const { + // Ill-formed gradient should not be rendered. + if (p1 == p0 || p2 == p0) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + UniquePtr<Pattern> solidColor = aColorLine->AsSolidColor(aState); + if (solidColor) { + return solidColor; + } + float firstStop, lastStop; + AutoTArray<GradientStop, 8> stopArray; + aColorLine->CollectGradientStops(aState, stopArray, &firstStop, &lastStop); + if (stopArray.IsEmpty()) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + if (firstStop != 0.0 || lastStop != 1.0) { + if (firstStop == lastStop) { + if (aColorLine->extend != T::EXTEND_PAD) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + // For extend-pad, when the color line is zero-length, we add a "fake" + // color stop to create a [0.0..1.0]-normalized color line, so that the + // projection of points below works as expected. + for (auto& gs : stopArray) { + gs.offset = 0.0f; + } + stopArray.AppendElement( + GradientStop{1.0f, stopArray.LastElement().color}); + lastStop += 1.0f; + } + // Adjust positions of the points to account for normalization of the + // color line stop offsets. + Point v = p1 - p0; + p0 += v * firstStop; + p1 -= v * (1.0f - lastStop); + // Move the rotation vector to maintain the same direction from p0. + p2 += v * firstStop; + } + Point p3; + if (FuzzyEqualsMultiplicative(p2.y, p0.y)) { + // rotation vector is horizontal + p3 = Point(p0.x, p1.y); + } else if (FuzzyEqualsMultiplicative(p2.x, p0.x)) { + // rotation vector is vertical + p3 = Point(p1.x, p0.y); + } else { + float m = (p2.y - p0.y) / (p2.x - p0.x); // slope of line p0->p2 + float mInv = -1.0f / m; // slope of desired perpendicular p0->p3 + float c1 = p0.y - mInv * p0.x; // line p0->p3 is m * x - y + c1 = 0 + float c2 = p1.y - m * p1.x; // line p1->p3 is mInv * x - y + c2 = 0 + float x3 = (c1 - c2) / (m - mInv); + float y3 = (c1 * m - c2 * mInv) / (m - mInv); + p3 = Point(x3, y3); + } + RefPtr stops = aColorLine->MakeGradientStops(aState, stopArray); + return MakeUnique<LinearGradientPattern>(p0, p3, std::move(stops), + Matrix::Scaling(1.0, -1.0)); + } +}; + +struct PaintVarLinearGradient : public PaintLinearGradient { + enum { kFormat = 5 }; + uint32 varIndexBase; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + uint32_t clOffset = aOffset + colorLineOffset; + if (clOffset + sizeof(VarColorLine) + sizeof(VarColorStop) > + aState.mCOLRLength) { + return nullptr; + } + const auto* colorLine = reinterpret_cast<const VarColorLine*>( + aState.COLRv1BaseAddr() + clOffset); + Point p0(aState.F2P(ApplyVariation(aState, int16_t(x0), varIndexBase)), + aState.F2P( + ApplyVariation(aState, int16_t(y0), SatAdd(varIndexBase, 1)))); + Point p1(aState.F2P( + ApplyVariation(aState, int16_t(x1), SatAdd(varIndexBase, 2))), + aState.F2P( + ApplyVariation(aState, int16_t(y1), SatAdd(varIndexBase, 3)))); + Point p2(aState.F2P( + ApplyVariation(aState, int16_t(x2), SatAdd(varIndexBase, 4))), + aState.F2P( + ApplyVariation(aState, int16_t(y2), SatAdd(varIndexBase, 5)))); + return NormalizeAndMakeGradient(aState, colorLine, p0, p1, p2); + } +}; + +struct PaintRadialGradient : public PaintPatternBase { + enum { kFormat = 6 }; + uint8_t format; + Offset24 colorLineOffset; + FWORD x0; + FWORD y0; + UFWORD radius0; + FWORD x1; + FWORD y1; + UFWORD radius1; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + uint32_t clOffset = aOffset + colorLineOffset; + if (clOffset + sizeof(ColorLine) + sizeof(ColorStop) > aState.mCOLRLength) { + return nullptr; + } + const auto* colorLine = + reinterpret_cast<const ColorLine*>(aState.COLRv1BaseAddr() + clOffset); + Point c1(aState.F2P(int16_t(x0)), aState.F2P(int16_t(y0))); + Point c2(aState.F2P(int16_t(x1)), aState.F2P(int16_t(y1))); + float r1 = aState.F2P(uint16_t(radius0)); + float r2 = aState.F2P(uint16_t(radius1)); + return NormalizeAndMakeGradient(aState, colorLine, c1, c2, r1, r2); + } + + // Helper function to trim the gradient stops array at the start or end. + void TruncateGradientStops(nsTArray<GradientStop>& aStops, float aStart, + float aEnd) const { + // For pad mode, we may need a sub-range of the line: figure out which + // stops to trim, and interpolate as needed at truncation point(s). + // (Currently this is only ever used to trim one end of the color line, + // so edge cases that may occur when trimming both ends are untested.) + MOZ_ASSERT(aStart == 0.0f || aEnd == 1.0f, + "Trimming both ends of color-line is untested!"); + + // Create a color that is |r| of the way from c1 to c2. + auto interpolateColor = [](DeviceColor c1, DeviceColor c2, float r) { + return DeviceColor( + c2.r * r + c1.r * (1.0f - r), c2.g * r + c1.g * (1.0f - r), + c2.b * r + c1.b * (1.0f - r), c2.a * r + c1.a * (1.0f - r)); + }; + + size_t count = aStops.Length(); + MOZ_ASSERT(count > 1); + + // Truncate at the start of the color line? + if (aStart > 0.0f) { + // Skip forward past any stops that can be dropped. + size_t i = 0; + while (i < count - 1 && aStops[i].offset < aStart) { + ++i; + } + // If we're not truncating exactly at a color-stop offset, shift the + // preceding stop to the truncation offset and interpolate its color. + if (i && aStops[i].offset > aStart) { + auto& prev = aStops[i - 1]; + auto& curr = aStops[i]; + float ratio = (aStart - prev.offset) / (curr.offset - prev.offset); + prev.color = interpolateColor(prev.color, curr.color, ratio); + prev.offset = aStart; + --i; // We don't want to remove this stop, as we adjusted it. + } + aStops.RemoveElementsAt(0, i); + // Re-normalize the remaining stops to the [0, 1] range. + if (aStart < 1.0f) { + float r = 1.0f / (1.0f - aStart); + for (auto& gs : aStops) { + gs.offset = r * (gs.offset - aStart); + } + } + } + + // Truncate at the end of the color line? + if (aEnd < 1.0f) { + // Skip back over any stops that can be dropped. + size_t i = count - 1; + while (i && aStops[i].offset > aEnd) { + --i; + } + // If we're not truncating exactly at a color-stop offset, shift the + // following stop to the truncation offset and interpolate its color. + if (i + 1 < count && aStops[i].offset < aEnd) { + auto& next = aStops[i + 1]; + auto& curr = aStops[i]; + float ratio = (aEnd - curr.offset) / (next.offset - curr.offset); + next.color = interpolateColor(curr.color, next.color, ratio); + next.offset = aEnd; + ++i; + } + aStops.RemoveElementsAt(i + 1, count - i - 1); + // Re-normalize the remaining stops to the [0, 1] range. + if (aEnd > 0.0f) { + float r = 1.0f / aEnd; + for (auto& gs : aStops) { + gs.offset = r * gs.offset; + } + } + } + } + + template <typename T> + UniquePtr<Pattern> NormalizeAndMakeGradient(const PaintState& aState, + const T* aColorLine, Point c1, + Point c2, float r1, + float r2) const { + if ((c1 == c2 && r1 == r2) || (r1 == 0.0 && r2 == 0.0)) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + UniquePtr<Pattern> solidColor = aColorLine->AsSolidColor(aState); + if (solidColor) { + return solidColor; + } + float firstStop, lastStop; + AutoTArray<GradientStop, 8> stopArray; + aColorLine->CollectGradientStops(aState, stopArray, &firstStop, &lastStop); + if (stopArray.IsEmpty()) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + // If the color stop offsets had to be normalized to the [0, 1] range, + // adjust the circle positions and radii to match. + if (firstStop != 0.0f || lastStop != 1.0f) { + if (firstStop == lastStop) { + if (aColorLine->extend != T::EXTEND_PAD) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + // For extend-pad, when the color line is zero-length, we add a "fake" + // color stop to ensure we'll maintain the orientation of the cone, + // otherwise when we adjust circles to account for the normalized color + // stops, the centers will coalesce and the cone or cylinder collapses. + for (auto& gs : stopArray) { + gs.offset = 0.0f; + } + stopArray.AppendElement( + GradientStop{1.0f, stopArray.LastElement().color}); + lastStop += 1.0f; + } + // Adjust centers along the vector between them, and scale radii for + // gradient line defined from 0.0 to 1.0. + Point vec = c2 - c1; + c1 += vec * firstStop; + c2 -= vec * (1.0f - lastStop); + float deltaR = r2 - r1; + r1 = r1 + deltaR * firstStop; + r2 = r2 - deltaR * (1.0f - lastStop); + } + if ((r1 < 0.0f || r2 < 0.0f) && aColorLine->extend == T::EXTEND_PAD) { + // For EXTEND_PAD, we can restrict the gradient definition to just its + // visible portion because the shader doesn't need to see any part of the + // color line that extends into the negative-radius "virtual cone". + if (r1 < 0.0f && r2 < 0.0f) { + // If both radii are negative, then only the color at the closer circle + // will appear in the projected positive cone (or if they're equal, + // nothing will be visible at all). + if (r1 == r2) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + // The defined range of the color line is entirely in the invisible + // cone; all that will project into visible space is a single color. + if (r1 < r2) { + // Keep only the last color stop. + stopArray.RemoveElementsAt(0, stopArray.Length() - 1); + } else { + // Keep only the first color stop. + stopArray.RemoveElementsAt(1, stopArray.Length() - 1); + } + } else { + // Truncate the gradient at the tip of the visible cone: find the color + // stops closest to that point and interpolate between them. + if (r1 < r2) { + float start = r1 / (r1 - r2); + TruncateGradientStops(stopArray, start, 1.0f); + r1 = 0.0f; + c1 = c1 * (1.0f - start) + c2 * start; + } else if (r2 < r1) { + float end = 1.0f - r2 / (r2 - r1); + TruncateGradientStops(stopArray, 0.0f, end); + r2 = 0.0f; + c2 = c1 * (1.0f - end) + c2 * end; + } + } + } + // Handle negative radii, which the shader won't understand directly, by + // projecting the circles along the cones such that both radii are positive. + if (r1 < 0.0f || r2 < 0.0f) { + float deltaR = r2 - r1; + // If deltaR is zero, then nothing is visible because the cone has + // degenerated into a negative-radius cylinder, and does not project + // into visible space at all. + if (deltaR == 0.0f) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + Point vec = c2 - c1; + if (aColorLine->extend == T::EXTEND_REFLECT) { + deltaR *= 2.0f; + vec = vec * 2.0f; + } + if (r2 < r1) { + vec = -vec; + deltaR = -deltaR; + } + // Number of repeats by which we need to shift. + float n = std::ceil(std::max(-r1, -r2) / deltaR); + deltaR *= n; + r1 += deltaR; + r2 += deltaR; + vec = vec * n; + c1 += vec; + c2 += vec; + } + RefPtr stops = aColorLine->MakeGradientStops(aState, stopArray); + if (!stops) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + return MakeUnique<RadialGradientPattern>(c1, c2, r1, r2, std::move(stops), + Matrix::Scaling(1.0, -1.0)); + } +}; + +struct PaintVarRadialGradient : public PaintRadialGradient { + enum { kFormat = 7 }; + uint32 varIndexBase; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + uint32_t clOffset = aOffset + colorLineOffset; + if (clOffset + sizeof(VarColorLine) + sizeof(VarColorStop) > + aState.mCOLRLength) { + return nullptr; + } + const auto* colorLine = reinterpret_cast<const VarColorLine*>( + aState.COLRv1BaseAddr() + clOffset); + Point c1(aState.F2P(ApplyVariation(aState, int16_t(x0), varIndexBase)), + aState.F2P( + ApplyVariation(aState, int16_t(y0), SatAdd(varIndexBase, 1)))); + float r1 = aState.F2P( + ApplyVariation(aState, uint16_t(radius0), SatAdd(varIndexBase, 2))); + Point c2(aState.F2P( + ApplyVariation(aState, int16_t(x1), SatAdd(varIndexBase, 3))), + aState.F2P( + ApplyVariation(aState, int16_t(y1), SatAdd(varIndexBase, 4)))); + float r2 = aState.F2P( + ApplyVariation(aState, uint16_t(radius1), SatAdd(varIndexBase, 5))); + return NormalizeAndMakeGradient(aState, colorLine, c1, c2, r1, r2); + } +}; + +struct PaintSweepGradient : public PaintPatternBase { + enum { kFormat = 8 }; + uint8_t format; + Offset24 colorLineOffset; + FWORD centerX; + FWORD centerY; + F2DOT14 startAngle; + F2DOT14 endAngle; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + uint32_t clOffset = aOffset + colorLineOffset; + if (clOffset + sizeof(ColorLine) + sizeof(ColorStop) > aState.mCOLRLength) { + return nullptr; + } + const auto* colorLine = + reinterpret_cast<const ColorLine*>(aState.COLRv1BaseAddr() + clOffset); + float start = float(startAngle) + 1.0f; + float end = float(endAngle) + 1.0f; + Point center(aState.F2P(int16_t(centerX)), aState.F2P(int16_t(centerY))); + return NormalizeAndMakeGradient(aState, colorLine, center, start, end); + } + + template <typename T> + UniquePtr<Pattern> NormalizeAndMakeGradient(const PaintState& aState, + const T* aColorLine, + Point aCenter, float aStart, + float aEnd) const { + if (aStart == aEnd && aColorLine->extend != T::EXTEND_PAD) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + UniquePtr<Pattern> solidColor = aColorLine->AsSolidColor(aState); + if (solidColor) { + return solidColor; + } + // ConicGradientPattern works counterclockwise. If the gradient is defined + // clockwise (with aStart greater than aEnd), we'll reverse the color line + // and swap the start and end angles. + bool reverse = aEnd < aStart; + float firstStop, lastStop; + RefPtr stops = + aColorLine->MakeGradientStops(aState, &firstStop, &lastStop, reverse); + if (!stops) { + return nullptr; + } + if (firstStop != 0.0 || lastStop != 1.0) { + if (firstStop == lastStop) { + if (aColorLine->extend != T::EXTEND_PAD) { + return MakeUnique<ColorPattern>(DeviceColor()); + } + } else { + float sweep = aEnd - aStart; + aStart = aStart + sweep * firstStop; + aEnd = aStart + sweep * (lastStop - firstStop); + } + } + if (reverse) { + std::swap(aStart, aEnd); + } + return MakeUnique<ConicGradientPattern>(aCenter, M_PI / 2.0, aStart / 2.0, + aEnd / 2.0, std::move(stops), + Matrix::Scaling(1.0, -1.0)); + } +}; + +struct PaintVarSweepGradient : public PaintSweepGradient { + enum { kFormat = 9 }; + uint32 varIndexBase; + + UniquePtr<Pattern> MakePattern(const PaintState& aState, + uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + uint32_t clOffset = aOffset + colorLineOffset; + if (clOffset + sizeof(VarColorLine) + sizeof(VarColorStop) > + aState.mCOLRLength) { + return nullptr; + } + const auto* colorLine = reinterpret_cast<const VarColorLine*>( + aState.COLRv1BaseAddr() + clOffset); + float start = + ApplyVariation(aState, startAngle, SatAdd(varIndexBase, 2)) + 1.0f; + float end = + ApplyVariation(aState, endAngle, SatAdd(varIndexBase, 3)) + 1.0f; + Point center( + aState.F2P(ApplyVariation(aState, int16_t(centerX), varIndexBase)), + aState.F2P( + ApplyVariation(aState, int16_t(centerY), SatAdd(varIndexBase, 1)))); + return NormalizeAndMakeGradient(aState, colorLine, center, start, end); + } +}; + +struct PaintGlyph { + enum { kFormat = 10 }; + uint8_t format; + Offset24 paintOffset; + uint16 glyphID; + + bool Paint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) const { + MOZ_ASSERT(format == kFormat); + if (!paintOffset) { + return true; + } + Glyph g{uint16_t(glyphID), Point()}; + GlyphBuffer buffer{&g, 1}; + // If the paint is a simple fill (rather than a sub-graph of further paint + // records), we can just use FillGlyphs to render it instead of setting up + // a clip. + UniquePtr<Pattern> fillPattern = + DispatchMakePattern(aState, aOffset + paintOffset); + if (fillPattern) { + // On macOS we can't use FillGlyphs because when we render the glyph, + // Core Text's own color font support may step in and ignore the + // pattern. So to avoid this, fill the glyph as a path instead. +#if XP_MACOSX + RefPtr<Path> path = + aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget); + aState.mDrawTarget->Fill(path, *fillPattern, aState.mDrawOptions); +#else + aState.mDrawTarget->FillGlyphs(aState.mScaledFont, buffer, *fillPattern, + aState.mDrawOptions); +#endif + return true; + } + RefPtr<Path> path = + aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget); + aState.mDrawTarget->PushClip(path); + bool ok = DispatchPaint(aState, aOffset + paintOffset, aBounds); + aState.mDrawTarget->PopClip(); + return ok; + } + + Rect GetBoundingRect(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Glyph g{uint16_t(glyphID), Point()}; + GlyphBuffer buffer{&g, 1}; + RefPtr<Path> path = + aState.mScaledFont->GetPathForGlyphs(buffer, aState.mDrawTarget); + return path->GetFastBounds(); + } +}; + +struct PaintColrGlyph { + enum { kFormat = 11 }; + uint8_t format; + uint16 glyphID; + + // Factored out as a helper because this is also used by the top-level + // PaintGlyphGraph function. + static bool DoPaint(const PaintState& aState, + const BaseGlyphPaintRecord* aBaseGlyphPaint, + uint32_t aGlyphId, const Rect* aBounds) { + AutoPopClips clips(aState.mDrawTarget); + Rect clipRect; + if (const auto* clipList = aState.mHeader.v1->clipList()) { + if (const auto* clip = clipList->GetClip(aGlyphId)) { + clipRect = clip->GetRect(aState); + clips.PushClipRect(clipRect); + if (!aBounds) { + aBounds = &clipRect; + } + } + } + return DispatchPaint( + aState, + aState.mHeader.v1->baseGlyphListOffset + aBaseGlyphPaint->paintOffset, + aBounds); + } + + bool Paint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) const { + MOZ_ASSERT(format == kFormat); + IF_CYCLE_RETURN(true); + const auto* base = aState.mHeader.v1->GetBaseGlyphPaint(glyphID); + return base ? DoPaint(aState, base, uint16_t(glyphID), aBounds) : false; + } + + Rect GetBoundingRect(const PaintState& aState, uint32_t aOffset) const { + IF_CYCLE_RETURN(Rect()); + if (const auto* clipList = aState.mHeader.v1->clipList()) { + if (const auto* clip = clipList->GetClip(uint16_t(glyphID))) { + return clip->GetRect(aState); + } + } + if (const auto* base = + aState.mHeader.v1->GetBaseGlyphPaint(uint16_t(glyphID))) { + return DispatchGetBounds( + aState, aState.mHeader.v1->baseGlyphListOffset + base->paintOffset); + } + return Rect(); + } +}; + +#undef IF_CYCLE_RETURN + +struct Affine2x3 { + Fixed xx; + Fixed yx; + Fixed xy; + Fixed yy; + Fixed dx; + Fixed dy; + + Matrix AsMatrix(const PaintState& aState) const { + // Flip signs because of opposite y-axis direction in moz2d vs opentype. + return Matrix(float(xx), -float(yx), -float(xy), float(yy), + aState.F2P(float(dx)), -aState.F2P(float(dy))); + } +}; + +struct VarAffine2x3 : public Affine2x3 { + uint32 varIndexBase; + + Matrix AsMatrix(const PaintState& aState) const { + return Matrix( + ApplyVariation(aState, xx, varIndexBase), + -ApplyVariation(aState, yx, SatAdd(varIndexBase, 1)), + -ApplyVariation(aState, xy, SatAdd(varIndexBase, 2)), + ApplyVariation(aState, yy, SatAdd(varIndexBase, 3)), + aState.F2P(ApplyVariation(aState, dx, SatAdd(varIndexBase, 4))), + -aState.F2P(ApplyVariation(aState, dy, SatAdd(varIndexBase, 5)))); + }; +}; + +struct PaintTransformBase { + uint8_t format; + Offset24 paintOffset; + + bool Paint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) const { + if (!paintOffset) { + return true; + } + AutoRestoreTransform saveTransform(aState.mDrawTarget); + aState.mDrawTarget->ConcatTransform(DispatchGetMatrix(aState, aOffset)); + return DispatchPaint(aState, aOffset + paintOffset, aBounds); + } + + Rect GetBoundingRect(const PaintState& aState, uint32_t aOffset) const { + if (!paintOffset) { + return Rect(); + } + Rect bounds = DispatchGetBounds(aState, aOffset + paintOffset); + bounds = DispatchGetMatrix(aState, aOffset).TransformBounds(bounds); + return bounds; + } +}; + +struct PaintTransform : public PaintTransformBase { + enum { kFormat = 12 }; + Offset24 transformOffset; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + if (aOffset + transformOffset + sizeof(Affine2x3) > aState.mCOLRLength) { + return Matrix(); + } + const auto* t = reinterpret_cast<const Affine2x3*>( + aState.COLRv1BaseAddr() + aOffset + transformOffset); + return t->AsMatrix(aState); + } +}; + +struct PaintVarTransform : public PaintTransformBase { + enum { kFormat = 13 }; + Offset24 transformOffset; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + if (aOffset + transformOffset + sizeof(VarAffine2x3) > aState.mCOLRLength) { + return Matrix(); + } + const auto* t = reinterpret_cast<const VarAffine2x3*>( + aState.COLRv1BaseAddr() + aOffset + transformOffset); + return t->AsMatrix(aState); + } +}; + +struct PaintTranslate : public PaintTransformBase { + enum { kFormat = 14 }; + FWORD dx; + FWORD dy; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return Matrix::Translation(aState.F2P(int16_t(dx)), + -aState.F2P(int16_t(dy))); + } +}; + +struct PaintVarTranslate : public PaintTranslate { + enum { kFormat = 15 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return Matrix::Translation( + aState.F2P(ApplyVariation(aState, int16_t(dx), varIndexBase)), + -aState.F2P( + ApplyVariation(aState, int16_t(dy), SatAdd(varIndexBase, 1)))); + } +}; + +struct PaintScale : public PaintTransformBase { + enum { kFormat = 16 }; + F2DOT14 scaleX; + F2DOT14 scaleY; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return Matrix::Scaling(float(scaleX), float(scaleY)); + } +}; + +struct PaintVarScale : public PaintScale { + enum { kFormat = 17 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return Matrix::Scaling( + ApplyVariation(aState, scaleX, varIndexBase), + ApplyVariation(aState, scaleY, SatAdd(varIndexBase, 1))); + } +}; + +struct PaintScaleAroundCenter : public PaintTransformBase { + enum { kFormat = 18 }; + F2DOT14 scaleX; + F2DOT14 scaleY; + FWORD centerX; + FWORD centerY; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Point center(aState.F2P(int16_t(centerX)), -aState.F2P(int16_t(centerY))); + return Matrix::Translation(center) + .PreScale(float(scaleX), float(scaleY)) + .PreTranslate(-center); + } +}; + +struct PaintVarScaleAroundCenter : public PaintScaleAroundCenter { + enum { kFormat = 19 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Point center(aState.F2P(ApplyVariation(aState, int16_t(centerX), + SatAdd(varIndexBase, 2))), + -aState.F2P(ApplyVariation(aState, int16_t(centerY), + SatAdd(varIndexBase, 3)))); + return Matrix::Translation(center) + .PreScale(ApplyVariation(aState, scaleX, varIndexBase), + ApplyVariation(aState, scaleY, SatAdd(varIndexBase, 1))) + .PreTranslate(-center); + } +}; + +struct PaintScaleUniform : public PaintTransformBase { + enum { kFormat = 20 }; + F2DOT14 scale; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return Matrix::Scaling(float(scale), float(scale)); + } +}; + +struct PaintVarScaleUniform : public PaintScaleUniform { + enum { kFormat = 21 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + float sc = ApplyVariation(aState, scale, varIndexBase); + return Matrix::Scaling(sc, sc); + } +}; + +struct PaintScaleUniformAroundCenter : public PaintTransformBase { + enum { kFormat = 22 }; + F2DOT14 scale; + FWORD centerX; + FWORD centerY; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Point center(aState.F2P(int16_t(centerX)), -aState.F2P(int16_t(centerY))); + return Matrix::Translation(center) + .PreScale(float(scale), float(scale)) + .PreTranslate(-center); + } +}; + +struct PaintVarScaleUniformAroundCenter : public PaintScaleUniformAroundCenter { + enum { kFormat = 23 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + float sc = ApplyVariation(aState, scale, varIndexBase); + Point center(aState.F2P(ApplyVariation(aState, int16_t(centerX), + SatAdd(varIndexBase, 1))), + -aState.F2P(ApplyVariation(aState, int16_t(centerY), + SatAdd(varIndexBase, 2)))); + return Matrix::Translation(center).PreScale(sc, sc).PreTranslate(-center); + } +}; + +struct PaintRotate : public PaintTransformBase { + enum { kFormat = 24 }; + F2DOT14 angle; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return Matrix::Rotation(-float(angle) * float(M_PI)); + } +}; + +struct PaintVarRotate : public PaintRotate { + enum { kFormat = 25 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + float ang = ApplyVariation(aState, angle, varIndexBase); + return Matrix::Rotation(-ang * float(M_PI)); + } +}; + +struct PaintRotateAroundCenter : public PaintTransformBase { + enum { kFormat = 26 }; + F2DOT14 angle; + FWORD centerX; + FWORD centerY; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Point center(aState.F2P(int16_t(centerX)), -aState.F2P(int16_t(centerY))); + return Matrix::Translation(center) + .PreRotate(-float(angle) * float(M_PI)) + .PreTranslate(-center); + } +}; + +struct PaintVarRotateAroundCenter : public PaintRotateAroundCenter { + enum { kFormat = 27 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + float ang = ApplyVariation(aState, angle, varIndexBase); + Point center(aState.F2P(ApplyVariation(aState, int16_t(centerX), + SatAdd(varIndexBase, 1))), + -aState.F2P(ApplyVariation(aState, int16_t(centerY), + SatAdd(varIndexBase, 2)))); + return Matrix::Translation(center) + .PreRotate(-ang * float(M_PI)) + .PreTranslate(-center); + } +}; + +static inline Matrix SkewMatrix(float aSkewX, float aSkewY) { + float xy = tanf(aSkewX * float(M_PI)); + float yx = tanf(aSkewY * float(M_PI)); + return std::isnan(xy) || std::isnan(yx) ? Matrix() + : Matrix(1.0, -yx, xy, 1.0, 0.0, 0.0); +} + +struct PaintSkew : public PaintTransformBase { + enum { kFormat = 28 }; + F2DOT14 xSkewAngle; + F2DOT14 ySkewAngle; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return SkewMatrix(float(xSkewAngle), float(ySkewAngle)); + } +}; + +struct PaintVarSkew : public PaintSkew { + enum { kFormat = 29 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + return SkewMatrix( + float(ApplyVariation(aState, xSkewAngle, varIndexBase)), + float(ApplyVariation(aState, ySkewAngle, SatAdd(varIndexBase, 1)))); + } +}; + +struct PaintSkewAroundCenter : public PaintTransformBase { + enum { kFormat = 30 }; + F2DOT14 xSkewAngle; + F2DOT14 ySkewAngle; + FWORD centerX; + FWORD centerY; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Point center(aState.F2P(int16_t(centerX)), -aState.F2P(int16_t(centerY))); + return Matrix::Translation(center) + .PreMultiply(SkewMatrix(float(xSkewAngle), float(ySkewAngle))) + .PreTranslate(-center); + } +}; + +struct PaintVarSkewAroundCenter : public PaintSkewAroundCenter { + enum { kFormat = 31 }; + uint32 varIndexBase; + + Matrix GetMatrix(const PaintState& aState, uint32_t aOffset) const { + MOZ_ASSERT(format == kFormat); + Point center(aState.F2P(ApplyVariation(aState, int16_t(centerX), + SatAdd(varIndexBase, 2))), + -aState.F2P(ApplyVariation(aState, int16_t(centerY), + SatAdd(varIndexBase, 3)))); + return Matrix::Translation(center) + .PreMultiply(SkewMatrix( + ApplyVariation(aState, xSkewAngle, varIndexBase), + ApplyVariation(aState, ySkewAngle, SatAdd(varIndexBase, 1)))) + .PreTranslate(-center); + } +}; + +struct PaintComposite { + enum { kFormat = 32 }; + uint8_t format; + Offset24 sourcePaintOffset; + uint8_t compositeMode; + Offset24 backdropPaintOffset; + + enum { + COMPOSITE_CLEAR = 0, + COMPOSITE_SRC = 1, + COMPOSITE_DEST = 2, + COMPOSITE_SRC_OVER = 3, + COMPOSITE_DEST_OVER = 4, + COMPOSITE_SRC_IN = 5, + COMPOSITE_DEST_IN = 6, + COMPOSITE_SRC_OUT = 7, + COMPOSITE_DEST_OUT = 8, + COMPOSITE_SRC_ATOP = 9, + COMPOSITE_DEST_ATOP = 10, + COMPOSITE_XOR = 11, + COMPOSITE_PLUS = 12, + COMPOSITE_SCREEN = 13, + COMPOSITE_OVERLAY = 14, + COMPOSITE_DARKEN = 15, + COMPOSITE_LIGHTEN = 16, + COMPOSITE_COLOR_DODGE = 17, + COMPOSITE_COLOR_BURN = 18, + COMPOSITE_HARD_LIGHT = 19, + COMPOSITE_SOFT_LIGHT = 20, + COMPOSITE_DIFFERENCE = 21, + COMPOSITE_EXCLUSION = 22, + COMPOSITE_MULTIPLY = 23, + COMPOSITE_HSL_HUE = 24, + COMPOSITE_HSL_SATURATION = 25, + COMPOSITE_HSL_COLOR = 26, + COMPOSITE_HSL_LUMINOSITY = 27 + }; + + bool Paint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) const { + MOZ_ASSERT(format == kFormat); + if (!backdropPaintOffset || !sourcePaintOffset) { + return true; + } + auto mapCompositionMode = [](uint8_t aMode) -> CompositionOp { + switch (aMode) { + default: + return CompositionOp::OP_SOURCE; + case COMPOSITE_CLEAR: + case COMPOSITE_SRC: + case COMPOSITE_DEST: + MOZ_ASSERT_UNREACHABLE("should have short-circuited"); + return CompositionOp::OP_SOURCE; + case COMPOSITE_SRC_OVER: + return CompositionOp::OP_OVER; + case COMPOSITE_DEST_OVER: + return CompositionOp::OP_DEST_OVER; + case COMPOSITE_SRC_IN: + return CompositionOp::OP_IN; + case COMPOSITE_DEST_IN: + return CompositionOp::OP_DEST_IN; + case COMPOSITE_SRC_OUT: + return CompositionOp::OP_OUT; + case COMPOSITE_DEST_OUT: + return CompositionOp::OP_DEST_OUT; + case COMPOSITE_SRC_ATOP: + return CompositionOp::OP_ATOP; + case COMPOSITE_DEST_ATOP: + return CompositionOp::OP_DEST_ATOP; + case COMPOSITE_XOR: + return CompositionOp::OP_XOR; + case COMPOSITE_PLUS: + return CompositionOp::OP_ADD; + case COMPOSITE_SCREEN: + return CompositionOp::OP_SCREEN; + case COMPOSITE_OVERLAY: + return CompositionOp::OP_OVERLAY; + case COMPOSITE_DARKEN: + return CompositionOp::OP_DARKEN; + case COMPOSITE_LIGHTEN: + return CompositionOp::OP_LIGHTEN; + case COMPOSITE_COLOR_DODGE: + return CompositionOp::OP_COLOR_DODGE; + case COMPOSITE_COLOR_BURN: + return CompositionOp::OP_COLOR_BURN; + case COMPOSITE_HARD_LIGHT: + return CompositionOp::OP_HARD_LIGHT; + case COMPOSITE_SOFT_LIGHT: + return CompositionOp::OP_SOFT_LIGHT; + case COMPOSITE_DIFFERENCE: + return CompositionOp::OP_DIFFERENCE; + case COMPOSITE_EXCLUSION: + return CompositionOp::OP_EXCLUSION; + case COMPOSITE_MULTIPLY: + return CompositionOp::OP_MULTIPLY; + case COMPOSITE_HSL_HUE: + return CompositionOp::OP_HUE; + case COMPOSITE_HSL_SATURATION: + return CompositionOp::OP_SATURATION; + case COMPOSITE_HSL_COLOR: + return CompositionOp::OP_COLOR; + case COMPOSITE_HSL_LUMINOSITY: + return CompositionOp::OP_LUMINOSITY; + } + }; + // Short-circuit cases: + if (compositeMode == COMPOSITE_CLEAR) { + return true; + } + if (compositeMode == COMPOSITE_SRC) { + return DispatchPaint(aState, aOffset + sourcePaintOffset, aBounds); + } + if (compositeMode == COMPOSITE_DEST) { + return DispatchPaint(aState, aOffset + backdropPaintOffset, aBounds); + } + + // We need bounds for the temporary surfaces; so if we didn't have + // explicitly-provided bounds from a clipList entry for the top-level + // glyph, then we need to determine the bounding rect here. + Rect bounds = aBounds ? *aBounds : GetBoundingRect(aState, aOffset); + if (bounds.IsEmpty()) { + return true; + } + bounds.RoundOut(); + + PaintState state = aState; + state.mDrawOptions.mCompositionOp = CompositionOp::OP_OVER; + IntSize intSize(int(bounds.width), int(bounds.height)); + + if (!aState.mDrawTarget->CanCreateSimilarDrawTarget( + intSize, SurfaceFormat::B8G8R8A8)) { + // We're not going to be able to render this, so just bail out. + // (Returning true rather than false means we'll just not paint this + // part of the glyph, but won't return an error and likely fall back + // to an ugly black blob.) + return true; + } + + // Draw the backdrop paint graph to a temporary surface. + RefPtr backdrop = aState.mDrawTarget->CreateSimilarDrawTarget( + intSize, SurfaceFormat::B8G8R8A8); + if (!backdrop) { + return true; + } + backdrop->SetTransform(Matrix::Translation(-bounds.TopLeft())); + state.mDrawTarget = backdrop; + if (!DispatchPaint(state, aOffset + backdropPaintOffset, &bounds)) { + return false; + } + + // Draw the source paint graph to another temp surface. + RefPtr source = aState.mDrawTarget->CreateSimilarDrawTarget( + intSize, SurfaceFormat::B8G8R8A8); + if (!source) { + return true; + } + source->SetTransform(Matrix::Translation(-bounds.TopLeft())); + state.mDrawTarget = source; + if (!DispatchPaint(state, aOffset + sourcePaintOffset, &bounds)) { + return false; + } + + // Composite the source onto the backdrop using the specified operation. + Rect localBounds(Point(), bounds.Size()); + RefPtr snapshot = source->Snapshot(); + backdrop->SetTransform(Matrix()); + backdrop->DrawSurface(snapshot, localBounds, localBounds, + DrawSurfaceOptions(), + DrawOptions(1.0, mapCompositionMode(compositeMode))); + + // And copy the composited result to our final destination. + snapshot = backdrop->Snapshot(); + aState.mDrawTarget->DrawSurface(snapshot, bounds, localBounds); + + return true; + } + + Rect GetBoundingRect(const PaintState& aState, uint32_t aOffset) const { + if (!backdropPaintOffset || !sourcePaintOffset) { + return Rect(); + } + // For now, just return the maximal bounds that could result; this could be + // smarter, returning just one of the rects or their intersection when + // appropriate for the composite mode in effect. + return DispatchGetBounds(aState, aOffset + backdropPaintOffset) + .Union(DispatchGetBounds(aState, aOffset + sourcePaintOffset)); + } +}; + +#pragma pack() + +const BaseGlyphPaintRecord* COLRv1Header::GetBaseGlyphPaint( + uint32_t aGlyphId) const { + const auto* list = baseGlyphList(); + if (!list) { + return nullptr; + } + auto compare = [](const void* key, const void* data) -> int { + uint32_t glyphId = (uint32_t)(uintptr_t)key; + const auto* paintRecord = + reinterpret_cast<const BaseGlyphPaintRecord*>(data); + uint32_t baseGlyphId = uint16_t(paintRecord->glyphID); + if (baseGlyphId == glyphId) { + return 0; + } + return baseGlyphId > glyphId ? -1 : 1; + }; + return reinterpret_cast<const BaseGlyphPaintRecord*>( + bsearch((void*)(uintptr_t)aGlyphId, list + 1, + uint32_t(list->numBaseGlyphPaintRecords), + sizeof(BaseGlyphPaintRecord), compare)); +} + +#define DO_CASE_VAR(T) \ + DO_CASE(Paint##T); \ + DO_CASE(PaintVar##T) + +// Process paint table at aOffset from start of COLRv1 table. +static bool DispatchPaint(const PaintState& aState, uint32_t aOffset, + const Rect* aBounds) { + if (aOffset >= aState.mCOLRLength) { + return false; + } + + const char* paint = aState.COLRv1BaseAddr() + aOffset; + // All paint table formats start with an 8-bit 'format' field. + uint8_t format = uint8_t(*paint); + +#define DO_CASE(T) \ + case T::kFormat: \ + return aOffset + sizeof(T) <= aState.mCOLRLength \ + ? reinterpret_cast<const T*>(paint)->Paint(aState, aOffset, \ + aBounds) \ + : false + + switch (format) { + DO_CASE(PaintColrLayers); + DO_CASE_VAR(Solid); + DO_CASE_VAR(LinearGradient); + DO_CASE_VAR(RadialGradient); + DO_CASE_VAR(SweepGradient); + DO_CASE(PaintGlyph); + DO_CASE(PaintColrGlyph); + DO_CASE_VAR(Transform); + DO_CASE_VAR(Translate); + DO_CASE_VAR(Scale); + DO_CASE_VAR(ScaleAroundCenter); + DO_CASE_VAR(ScaleUniform); + DO_CASE_VAR(ScaleUniformAroundCenter); + DO_CASE_VAR(Rotate); + DO_CASE_VAR(RotateAroundCenter); + DO_CASE_VAR(Skew); + DO_CASE_VAR(SkewAroundCenter); + DO_CASE(PaintComposite); + default: + break; + } + +#undef DO_CASE + + return false; +} + +// Get a gfx::Pattern corresponding to the given paint table, if it is a +// simple format that can be used as a fill (not a sub-graph). +static UniquePtr<Pattern> DispatchMakePattern(const PaintState& aState, + uint32_t aOffset) { + if (aOffset >= aState.mCOLRLength) { + return nullptr; + } + + const char* paint = aState.COLRv1BaseAddr() + aOffset; + // All paint table formats start with an 8-bit 'format' field. + uint8_t format = uint8_t(*paint); + +#define DO_CASE(T) \ + case T::kFormat: \ + return aOffset + sizeof(T) <= aState.mCOLRLength \ + ? reinterpret_cast<const T*>(paint)->MakePattern(aState, \ + aOffset) \ + : nullptr; + + switch (format) { + DO_CASE_VAR(Solid); + DO_CASE_VAR(LinearGradient); + DO_CASE_VAR(RadialGradient); + DO_CASE_VAR(SweepGradient); + default: + break; + } + +#undef DO_CASE + + return nullptr; +} + +static Matrix DispatchGetMatrix(const PaintState& aState, uint32_t aOffset) { + if (aOffset >= aState.mCOLRLength) { + return Matrix(); + } + + const char* paint = aState.COLRv1BaseAddr() + aOffset; + // All paint table formats start with an 8-bit 'format' field. + uint8_t format = uint8_t(*paint); + +#define DO_CASE(T) \ + case T::kFormat: \ + return aOffset + sizeof(T) <= aState.mCOLRLength \ + ? reinterpret_cast<const T*>(paint)->GetMatrix(aState, aOffset) \ + : Matrix(); + + switch (format) { + DO_CASE_VAR(Transform); + DO_CASE_VAR(Translate); + DO_CASE_VAR(Scale); + DO_CASE_VAR(ScaleAroundCenter); + DO_CASE_VAR(ScaleUniform); + DO_CASE_VAR(ScaleUniformAroundCenter); + DO_CASE_VAR(Rotate); + DO_CASE_VAR(RotateAroundCenter); + DO_CASE_VAR(Skew); + DO_CASE_VAR(SkewAroundCenter); + default: + break; + } + +#undef DO_CASE + + return Matrix(); +} + +static Rect DispatchGetBounds(const PaintState& aState, uint32_t aOffset) { + if (aOffset >= aState.mCOLRLength) { + return Rect(); + } + + const char* paint = aState.COLRv1BaseAddr() + aOffset; + // All paint table formats start with an 8-bit 'format' field. + uint8_t format = uint8_t(*paint); + +#define DO_CASE(T) \ + case T::kFormat: \ + return aOffset + sizeof(T) <= aState.mCOLRLength \ + ? reinterpret_cast<const T*>(paint)->GetBoundingRect(aState, \ + aOffset) \ + : Rect(); + + switch (format) { + DO_CASE(PaintColrLayers); + DO_CASE_VAR(Solid); + DO_CASE_VAR(LinearGradient); + DO_CASE_VAR(RadialGradient); + DO_CASE_VAR(SweepGradient); + DO_CASE(PaintGlyph); + DO_CASE(PaintColrGlyph); + DO_CASE_VAR(Transform); + DO_CASE_VAR(Translate); + DO_CASE_VAR(Scale); + DO_CASE_VAR(ScaleAroundCenter); + DO_CASE_VAR(ScaleUniform); + DO_CASE_VAR(ScaleUniformAroundCenter); + DO_CASE_VAR(Rotate); + DO_CASE_VAR(RotateAroundCenter); + DO_CASE_VAR(Skew); + DO_CASE_VAR(SkewAroundCenter); + DO_CASE(PaintComposite); + default: + break; + } + +#undef DO_CASE + + return Rect(); +} + +#undef DO_CASE_VAR + +bool COLRHeader::Validate(uint64_t aLength) const { + uint64_t count; + if ((count = numBaseGlyphRecords)) { + if (baseGlyphRecordsOffset + count * sizeof(BaseGlyphRecord) > aLength) { + return false; + } + } + if ((count = numLayerRecords)) { + if (layerRecordsOffset + count * sizeof(LayerRecord) > aLength) { + return false; + } + } + // Check ordering of baseGlyphRecords, and that layer indices are in bounds. + int32_t lastGlyphId = -1; + const auto* baseGlyph = reinterpret_cast<const BaseGlyphRecord*>( + reinterpret_cast<const char*>(this) + baseGlyphRecordsOffset); + for (uint16_t i = 0; i < uint16_t(numBaseGlyphRecords); i++, baseGlyph++) { + uint16_t glyphId = baseGlyph->glyphId; + if (lastGlyphId >= int32_t(glyphId)) { + return false; + } + if (uint32_t(baseGlyph->firstLayerIndex) + uint32_t(baseGlyph->numLayers) > + uint32_t(numLayerRecords)) { + return false; + } + lastGlyphId = glyphId; + } + // We don't need to validate all the layer paletteEntryIndex fields here, + // because PaintState.GetColor will range-check them at paint time. + return true; +} + +bool COLRv1Header::Validate(uint64_t aLength) const { + if (!base.Validate(aLength)) { + return false; + } + if (baseGlyphListOffset + sizeof(BaseGlyphList) > aLength || + layerListOffset + sizeof(LayerList) > aLength || + clipListOffset + sizeof(ClipList) > aLength || + varIndexMapOffset + sizeof(DeltaSetIndexMap) > aLength || + itemVariationStoreOffset + sizeof(ItemVariationStore) > aLength) { + return false; + } + const auto* b = baseGlyphList(); + if (b && !b->Validate(this, aLength)) { + return false; + } + const auto* l = layerList(); + if (l && !l->Validate(this, aLength)) { + return false; + } + const auto* c = clipList(); + if (c && !c->Validate(this, aLength)) { + return false; + } + const auto* v = varIndexMap(); + if (v && !v->Validate(this, aLength)) { + return false; + } + const auto* i = itemVariationStore(); + if (i && !i->Validate(this, aLength)) { + return false; + } + return true; +} + +bool BaseGlyphList::Validate(const COLRv1Header* aHeader, + uint64_t aLength) const { + uint64_t count = numBaseGlyphPaintRecords; + if (aHeader->baseGlyphListOffset + sizeof(BaseGlyphList) + + count * sizeof(BaseGlyphPaintRecord) > + aLength) { + return false; + } + // Check ordering of baseGlyphPaint records. + const auto* records = baseGlyphPaintRecords(); + int32_t prevGlyphID = -1; + for (uint32_t i = 0; i < numBaseGlyphPaintRecords; ++i) { + const auto& base = records[i]; + if (int32_t(uint16_t(base.glyphID)) <= prevGlyphID) { + return false; + } + prevGlyphID = base.glyphID; + } + return true; +} + +bool LayerList::Validate(const COLRv1Header* aHeader, uint64_t aLength) const { + // Check that paintOffsets array fits. + uint64_t count = numLayers; + uint32_t listOffset = aHeader->layerListOffset; + if (listOffset + sizeof(LayerList) + count * sizeof(uint32) > aLength) { + return false; + } + // Check that values in paintOffsets are within bounds. + const auto* offsets = paintOffsets(); + for (uint32_t i = 0; i < count; i++) { + if (listOffset + offsets[i] >= aLength) { + return false; + } + } + return true; +} + +bool Clip::Validate(const COLRv1Header* aHeader, uint64_t aLength) const { + uint32_t offset = aHeader->clipListOffset + clipBoxOffset; + if (offset >= aLength) { + return false; + } + // ClipBox format begins with a 1-byte format field. + const uint8_t* box = reinterpret_cast<const uint8_t*>(aHeader) + offset; + switch (*box) { + case 1: + if (offset <= aLength - sizeof(ClipBoxFormat1)) { + return true; + } + break; + case 2: + if (offset <= aLength - sizeof(ClipBoxFormat2)) { + return true; + } + break; + default: + // unknown ClipBoxFormat + break; + } + return false; +} + +bool ClipList::Validate(const COLRv1Header* aHeader, uint64_t aLength) const { + uint64_t count = numClips; + if (aHeader->clipListOffset + sizeof(ClipList) + count * sizeof(Clip) > + aLength) { + return false; + } + // Check ordering of clip records, and that they are within bounds. + const auto* clipArray = clips(); + int32_t prevEnd = -1; + for (uint32_t i = 0; i < count; ++i) { + const auto& clip = clipArray[i]; + if (int32_t(uint16_t(clip.startGlyphID)) <= prevEnd) { + return false; + } + if (!clip.Validate(aHeader, aLength)) { + return false; + } + prevEnd = uint16_t(clip.endGlyphID); + } + return true; +} + +bool DeltaSetIndexMap::Validate(const COLRv1Header* aHeader, + uint64_t aLength) const { + uint64_t entrySize = ((entryFormat & MAP_ENTRY_SIZE_MASK) >> 4) + 1; + uint64_t mapCount; + uint64_t baseSize; + switch (format) { + case 0: + mapCount = uint32_t(v0.mapCount); + baseSize = 4; + break; + case 1: + mapCount = uint32_t(v1.mapCount); + baseSize = 6; + break; + default: + return false; + } + if (aHeader->varIndexMapOffset + baseSize + mapCount * entrySize > aLength) { + return false; + } + return true; +} + +bool ItemVariationStore::Validate(const COLRv1Header* aHeader, + uint64_t aLength) const { + uint64_t offset = reinterpret_cast<const char*>(this) - + reinterpret_cast<const char*>(aHeader); + if (offset + variationRegionListOffset + sizeof(VariationRegionList) > + aLength) { + return false; + } + if (!variationRegionList()->Validate(aHeader, aLength)) { + return false; + } + uint16_t count = itemVariationDataCount; + if (offset + sizeof(ItemVariationStore) + count * sizeof(Offset32) > + aLength) { + return false; + } + const auto* ivdOffsets = itemVariationDataOffsets(); + for (uint16_t i = 0; i < count; ++i) { + uint32_t o = ivdOffsets[i]; + if (offset + o + sizeof(ItemVariationData) > aLength) { + return false; + } + const auto* variationData = reinterpret_cast<const ItemVariationData*>( + reinterpret_cast<const char*>(this) + ivdOffsets[i]); + if (!variationData->Validate(aHeader, aLength)) { + return false; + } + } + return true; +} + +bool ItemVariationData::Validate(const COLRv1Header* aHeader, + uint64_t aLength) const { + if (reinterpret_cast<const char*>(regionIndexes() + + uint16_t(regionIndexCount)) > + reinterpret_cast<const char*>(aHeader) + aLength) { + return false; + } + uint16_t wordDeltaCount = this->wordDeltaCount; + bool longWords = wordDeltaCount & LONG_WORDS; + wordDeltaCount &= WORD_DELTA_COUNT_MASK; + uint32_t deltaSetSize = + (uint16_t(regionIndexCount) + uint16_t(wordDeltaCount)) << longWords; + if (reinterpret_cast<const char*>(deltaSets()) + + uint16_t(itemCount) * deltaSetSize > + reinterpret_cast<const char*>(aHeader) + aLength) { + return false; + } + return true; +} + +} // end anonymous namespace + +namespace mozilla::gfx { + +bool COLRFonts::ValidateColorGlyphs(hb_blob_t* aCOLR, hb_blob_t* aCPAL) { + struct ColorRecord { + uint8_t blue; + uint8_t green; + uint8_t red; + uint8_t alpha; + }; + + struct CPALHeaderVersion0 { + uint16 version; + uint16 numPaletteEntries; + uint16 numPalettes; + uint16 numColorRecords; + Offset32 colorRecordsArrayOffset; + // uint16 colorRecordIndices[numPalettes]; + const uint16* colorRecordIndices() const { + return reinterpret_cast<const uint16*>(this + 1); + } + }; + + unsigned int cpalLength; + const CPALHeaderVersion0* cpal = reinterpret_cast<const CPALHeaderVersion0*>( + hb_blob_get_data(aCPAL, &cpalLength)); + if (!cpal || cpalLength < sizeof(CPALHeaderVersion0)) { + return false; + } + + // We can handle either version 0 or 1. + if (uint16_t(cpal->version) > 1) { + return false; + } + + uint16_t numPaletteEntries = cpal->numPaletteEntries; + uint16_t numPalettes = cpal->numPalettes; + uint16_t numColorRecords = cpal->numColorRecords; + uint32_t colorRecordsArrayOffset = cpal->colorRecordsArrayOffset; + const auto* indices = cpal->colorRecordIndices(); + if (colorRecordsArrayOffset >= cpalLength) { + return false; + } + if (!numPaletteEntries || !numPalettes || + numColorRecords < numPaletteEntries) { + return false; + } + if (sizeof(ColorRecord) * numColorRecords > + cpalLength - colorRecordsArrayOffset) { + return false; + } + if (sizeof(uint16) * numPalettes > cpalLength - sizeof(CPALHeaderVersion0)) { + return false; + } + for (uint16_t i = 0; i < numPalettes; ++i) { + uint32_t index = indices[i]; + if (index + numPaletteEntries > numColorRecords) { + return false; + } + } + + // The additional fields in CPALv1 are not checked here; the harfbuzz code + // handles reading them safely. + + unsigned int colrLength; + const COLRHeader* colr = + reinterpret_cast<const COLRHeader*>(hb_blob_get_data(aCOLR, &colrLength)); + if (!colr || colrLength < sizeof(COLRHeader)) { + return false; + } + + if (uint16_t(colr->version) == 1) { + return StaticPrefs::gfx_font_rendering_colr_v1_enabled() && + colrLength >= sizeof(COLRv1Header) && + reinterpret_cast<const COLRv1Header*>(colr)->Validate(colrLength); + } + + if (uint16_t(colr->version) != 0) { + // We only support version 1 (above) or version 0 headers. + return false; + } + + return colr->Validate(colrLength); +} + +const COLRFonts::GlyphLayers* COLRFonts::GetGlyphLayers(hb_blob_t* aCOLR, + uint32_t aGlyphId) { + unsigned int length; + const COLRHeader* colr = + reinterpret_cast<const COLRHeader*>(hb_blob_get_data(aCOLR, &length)); + // This should never be called unless we have checked that the COLR table is + // structurally valid, so it will be safe to read the header fields. + MOZ_RELEASE_ASSERT(colr && length >= sizeof(COLRHeader), "bad COLR table!"); + auto compareBaseGlyph = [](const void* key, const void* data) -> int { + uint32_t glyphId = (uint32_t)(uintptr_t)key; + const auto* baseGlyph = reinterpret_cast<const BaseGlyphRecord*>(data); + uint32_t baseGlyphId = uint16_t(baseGlyph->glyphId); + if (baseGlyphId == glyphId) { + return 0; + } + return baseGlyphId > glyphId ? -1 : 1; + }; + return reinterpret_cast<const GlyphLayers*>( + bsearch((void*)(uintptr_t)aGlyphId, colr->GetBaseGlyphRecords(), + uint16_t(colr->numBaseGlyphRecords), sizeof(BaseGlyphRecord), + compareBaseGlyph)); +} + +bool COLRFonts::PaintGlyphLayers( + hb_blob_t* aCOLR, hb_face_t* aFace, const GlyphLayers* aLayers, + DrawTarget* aDrawTarget, layout::TextDrawTarget* aTextDrawer, + ScaledFont* aScaledFont, DrawOptions aDrawOptions, const Point& aPoint, + const sRGBColor& aCurrentColor, const nsTArray<sRGBColor>* aColors) { + const auto* glyphRecord = reinterpret_cast<const BaseGlyphRecord*>(aLayers); + // Default to opaque rendering (non-webrender applies alpha with a layer) + float alpha = 1.0; + if (aTextDrawer) { + // defaultColor is the one that comes from CSS, so it has transparency info. + bool hasComplexTransparency = + 0.0 < aCurrentColor.a && aCurrentColor.a < 1.0; + if (hasComplexTransparency && uint16_t(glyphRecord->numLayers) > 1) { + // WebRender doesn't support drawing multi-layer transparent color-glyphs, + // as it requires compositing all the layers before applying transparency. + // (pretend to succeed, output doesn't matter, we will emit a blob) + aTextDrawer->FoundUnsupportedFeature(); + return true; + } + + // If we get here, then either alpha is 0 or 1, or there's only one layer + // which shouldn't have composition issues. In all of these cases, applying + // transparency directly to the glyph should work perfectly fine. + // + // Note that we must still emit completely transparent emoji, because they + // might be wrapped in a shadow that uses the text run's glyphs. + alpha = aCurrentColor.a; + } + + unsigned int length; + const COLRHeader* colr = + reinterpret_cast<const COLRHeader*>(hb_blob_get_data(aCOLR, &length)); + PaintState state{{colr}, + aColors->Elements(), + aDrawTarget, + aScaledFont, + nullptr, // variations not needed + aDrawOptions, + length, + aCurrentColor, + 0.0, // fontUnitsToPixels not needed + uint16_t(aColors->Length()), + 0, + nullptr}; + return glyphRecord->Paint(state, alpha, aPoint); +} + +const COLRFonts::GlyphPaintGraph* COLRFonts::GetGlyphPaintGraph( + hb_blob_t* aCOLR, uint32_t aGlyphId) { + if (!StaticPrefs::gfx_font_rendering_colr_v1_enabled()) { + return nullptr; + } + unsigned int blobLength; + const auto* colr = + reinterpret_cast<const COLRHeader*>(hb_blob_get_data(aCOLR, &blobLength)); + MOZ_ASSERT(colr, "Cannot get COLR raw data"); + MOZ_ASSERT(blobLength >= sizeof(COLRHeader), "COLR data too small"); + + uint16_t version = colr->version; + if (version == 1) { + MOZ_ASSERT(blobLength >= sizeof(COLRv1Header), "COLRv1 data too small"); + const auto* colrv1 = reinterpret_cast<const COLRv1Header*>(colr); + return reinterpret_cast<const GlyphPaintGraph*>( + colrv1->GetBaseGlyphPaint(aGlyphId)); + } + + return nullptr; +} + +bool COLRFonts::PaintGlyphGraph( + hb_blob_t* aCOLR, hb_font_t* aFont, const GlyphPaintGraph* aPaintGraph, + DrawTarget* aDrawTarget, layout::TextDrawTarget* aTextDrawer, + ScaledFont* aScaledFont, DrawOptions aDrawOptions, const Point& aPoint, + const sRGBColor& aCurrentColor, const nsTArray<sRGBColor>* aColors, + uint32_t aGlyphId, float aFontUnitsToPixels) { + if (aTextDrawer) { + // Currently we always punt to a blob for COLRv1 glyphs. + aTextDrawer->FoundUnsupportedFeature(); + return true; + } + + unsigned int coordCount; + const int* coords = hb_font_get_var_coords_normalized(aFont, &coordCount); + + AutoTArray<uint32_t, 32> visitedOffsets; + PaintState state{{nullptr}, + aColors->Elements(), + aDrawTarget, + aScaledFont, + coords, + aDrawOptions, + hb_blob_get_length(aCOLR), + aCurrentColor, + aFontUnitsToPixels, + uint16_t(aColors->Length()), + uint16_t(coordCount), + &visitedOffsets}; + state.mHeader.v1 = + reinterpret_cast<const COLRv1Header*>(hb_blob_get_data(aCOLR, nullptr)); + AutoRestoreTransform saveTransform(aDrawTarget); + aDrawTarget->ConcatTransform(Matrix::Translation(aPoint)); + return PaintColrGlyph::DoPaint( + state, reinterpret_cast<const BaseGlyphPaintRecord*>(aPaintGraph), + aGlyphId, nullptr); +} + +Rect COLRFonts::GetColorGlyphBounds(hb_blob_t* aCOLR, hb_font_t* aFont, + uint32_t aGlyphId, DrawTarget* aDrawTarget, + ScaledFont* aScaledFont, + float aFontUnitsToPixels) { + unsigned int coordCount; + const int* coords = hb_font_get_var_coords_normalized(aFont, &coordCount); + + AutoTArray<uint32_t, 32> visitedOffsets; + PaintState state{{nullptr}, + nullptr, // palette is not needed + aDrawTarget, + aScaledFont, + coords, + DrawOptions(), + hb_blob_get_length(aCOLR), + sRGBColor(), + aFontUnitsToPixels, + 0, // numPaletteEntries + uint16_t(coordCount), + &visitedOffsets}; + state.mHeader.v1 = + reinterpret_cast<const COLRv1Header*>(hb_blob_get_data(aCOLR, nullptr)); + MOZ_ASSERT(uint16_t(state.mHeader.v1->base.version) == 1); + // If a clip rect is provided, return this as the glyph bounds. + const auto* clipList = state.mHeader.v1->clipList(); + if (clipList) { + const auto* clip = clipList->GetClip(aGlyphId); + if (clip) { + return clip->GetRect(state); + } + } + // Otherwise, compute bounds by walking the paint graph. + const auto* base = state.mHeader.v1->GetBaseGlyphPaint(aGlyphId); + if (base) { + return DispatchGetBounds( + state, state.mHeader.v1->baseGlyphListOffset + base->paintOffset); + } + return Rect(); +} + +uint16_t COLRFonts::GetColrTableVersion(hb_blob_t* aCOLR) { + unsigned int blobLength; + const auto* colr = + reinterpret_cast<const COLRHeader*>(hb_blob_get_data(aCOLR, &blobLength)); + MOZ_ASSERT(colr, "Cannot get COLR raw data"); + MOZ_ASSERT(blobLength >= sizeof(COLRHeader), "COLR data too small"); + return colr->version; +} + +UniquePtr<nsTArray<sRGBColor>> COLRFonts::SetupColorPalette( + hb_face_t* aFace, const FontPaletteValueSet* aPaletteValueSet, + nsAtom* aFontPalette, const nsACString& aFamilyName) { + // Find the base color palette to use, if there are multiple available; + // default to first in the font, if nothing matches what is requested. + unsigned int paletteIndex = 0; + unsigned int count = hb_ot_color_palette_get_count(aFace); + MOZ_ASSERT(count > 0, "No palettes? Font should have been rejected!"); + + const FontPaletteValueSet::PaletteValues* fpv = nullptr; + if (aFontPalette && aFontPalette != nsGkAtoms::normal && + (count > 1 || aPaletteValueSet)) { + auto findPalette = [&](hb_ot_color_palette_flags_t flag) -> unsigned int { + MOZ_ASSERT(flag != HB_OT_COLOR_PALETTE_FLAG_DEFAULT); + for (unsigned int i = 0; i < count; ++i) { + if (hb_ot_color_palette_get_flags(aFace, i) & flag) { + return i; + } + } + return 0; + }; + + if (aFontPalette == nsGkAtoms::light) { + paletteIndex = + findPalette(HB_OT_COLOR_PALETTE_FLAG_USABLE_WITH_LIGHT_BACKGROUND); + } else if (aFontPalette == nsGkAtoms::dark) { + paletteIndex = + findPalette(HB_OT_COLOR_PALETTE_FLAG_USABLE_WITH_DARK_BACKGROUND); + } else { + if (aPaletteValueSet) { + if ((fpv = aPaletteValueSet->Lookup(aFontPalette, aFamilyName))) { + if (fpv->mBasePalette >= 0 && fpv->mBasePalette < int32_t(count)) { + paletteIndex = fpv->mBasePalette; + } else if (fpv->mBasePalette == + FontPaletteValueSet::PaletteValues::kLight) { + paletteIndex = findPalette( + HB_OT_COLOR_PALETTE_FLAG_USABLE_WITH_LIGHT_BACKGROUND); + } else if (fpv->mBasePalette == + FontPaletteValueSet::PaletteValues::kDark) { + paletteIndex = findPalette( + HB_OT_COLOR_PALETTE_FLAG_USABLE_WITH_DARK_BACKGROUND); + } + } + } + } + } + + // Collect the palette colors and convert them to sRGBColor values. + count = + hb_ot_color_palette_get_colors(aFace, paletteIndex, 0, nullptr, nullptr); + nsTArray<hb_color_t> colors; + colors.SetLength(count); + hb_ot_color_palette_get_colors(aFace, paletteIndex, 0, &count, + colors.Elements()); + + auto palette = MakeUnique<nsTArray<sRGBColor>>(); + palette->SetCapacity(count); + for (const auto c : colors) { + palette->AppendElement( + sRGBColor(hb_color_get_red(c) / 255.0, hb_color_get_green(c) / 255.0, + hb_color_get_blue(c) / 255.0, hb_color_get_alpha(c) / 255.0)); + } + + // Apply @font-palette-values overrides, if present. + if (fpv) { + for (const auto overrideColor : fpv->mOverrides) { + if (overrideColor.mIndex < palette->Length()) { + (*palette)[overrideColor.mIndex] = overrideColor.mColor; + } + } + } + + return palette; +} + +const FontPaletteValueSet::PaletteValues* FontPaletteValueSet::Lookup( + nsAtom* aName, const nsACString& aFamily) const { + nsAutoCString family(aFamily); + ToLowerCase(family); + if (const HashEntry* entry = + mValues.GetEntry(PaletteHashKey(aName, family))) { + return &entry->mValue; + } + return nullptr; +} + +FontPaletteValueSet::PaletteValues* FontPaletteValueSet::Insert( + nsAtom* aName, const nsACString& aFamily) { + nsAutoCString family(aFamily); + ToLowerCase(family); + HashEntry* entry = mValues.PutEntry(PaletteHashKey(aName, family)); + return &entry->mValue; +} + +} // end namespace mozilla::gfx |