1 // Copyright 2019 Google LLC. 2 #ifndef LineBreaker_DEFINED 3 #define LineBreaker_DEFINED 4 5 #include <functional> // std::function 6 #include <queue> 7 #include "include/core/SkSpan.h" 8 #include "modules/skparagraph/include/TextStyle.h" 9 #include "modules/skparagraph/src/ParagraphImpl.h" 10 #include "modules/skparagraph/src/Run.h" 11 12 namespace skia { 13 namespace textlayout { 14 15 class ParagraphImpl; 16 class OneLineShaper : public SkShaper::RunHandler { 17 public: OneLineShaper(ParagraphImpl * paragraph)18 explicit OneLineShaper(ParagraphImpl* paragraph) 19 : fParagraph(paragraph) 20 , fHeight(0.0f) 21 , fUseHalfLeading(false) 22 , fBaselineShift(0.0f) 23 , fAdvance(SkPoint::Make(0.0f, 0.0f)) 24 , fUnresolvedGlyphs(0) 25 , fUniqueRunId(paragraph->fRuns.size()){ } 26 27 bool shape(); 28 unresolvedGlyphs()29 size_t unresolvedGlyphs() { return fUnresolvedGlyphs; } 30 31 private: 32 33 struct RunBlock { RunBlockRunBlock34 RunBlock() : fRun(nullptr) { } 35 36 // First unresolved block RunBlockRunBlock37 explicit RunBlock(TextRange text) : fRun(nullptr), fText(text) { } 38 RunBlockRunBlock39 RunBlock(std::shared_ptr<Run> run, TextRange text, GlyphRange glyphs, size_t score) 40 : fRun(std::move(run)) 41 , fText(text) 42 , fGlyphs(glyphs) { } 43 44 // Entire run comes as one block fully resolved RunBlockRunBlock45 explicit RunBlock(std::shared_ptr<Run> run) 46 : fRun(std::move(run)) 47 , fText(fRun->fTextRange) 48 , fGlyphs(GlyphRange(0, fRun->size())) { } 49 50 std::shared_ptr<Run> fRun; 51 TextRange fText; 52 GlyphRange fGlyphs; isFullyResolvedRunBlock53 bool isFullyResolved() { return fRun != nullptr && fGlyphs.width() == fRun->size(); } 54 }; 55 56 using ShapeVisitor = 57 std::function<SkScalar(TextRange textRange, SkSpan<Block>, SkScalar&, TextIndex, uint8_t)>; 58 bool iterateThroughShapingRegions(const ShapeVisitor& shape); 59 60 using ShapeSingleFontVisitor = 61 std::function<void(Block, SkTArray<SkShaper::Feature>)>; 62 void iterateThroughFontStyles( 63 TextRange textRange, SkSpan<Block> styleSpan, const ShapeSingleFontVisitor& visitor); 64 65 enum Resolved { 66 Nothing, 67 Something, 68 Everything 69 }; 70 71 using TypefaceVisitor = std::function<Resolved(sk_sp<SkTypeface> typeface)>; 72 void matchResolvedFonts(const TextStyle& textStyle, const TypefaceVisitor& visitor); 73 #ifdef SK_DEBUG 74 void printState(); 75 #endif 76 void finish(const Block& block, SkScalar height, SkScalar& advanceX); 77 beginLine()78 void beginLine() override {} runInfo(const RunInfo &)79 void runInfo(const RunInfo&) override {} commitRunInfo()80 void commitRunInfo() override {} commitLine()81 void commitLine() override {} 82 runBuffer(const RunInfo & info)83 Buffer runBuffer(const RunInfo& info) override { 84 fCurrentRun = std::make_shared<Run>(fParagraph, 85 info, 86 fCurrentText.start, 87 fHeight, 88 fUseHalfLeading, 89 fBaselineShift, 90 ++fUniqueRunId, 91 fAdvance.fX); 92 return fCurrentRun->newRunBuffer(); 93 } 94 95 void commitRunBuffer(const RunInfo&) override; 96 97 TextRange clusteredText(GlyphRange& glyphs); clusterIndex(GlyphIndex glyph)98 ClusterIndex clusterIndex(GlyphIndex glyph) { 99 return fCurrentText.start + fCurrentRun->fClusterIndexes[glyph]; 100 } 101 void addFullyResolved(); 102 void addUnresolvedWithRun(GlyphRange glyphRange); 103 void sortOutGlyphs(std::function<void(GlyphRange)>&& sortOutUnresolvedBLock); 104 ClusterRange normalizeTextRange(GlyphRange glyphRange); 105 void fillGaps(size_t); 106 BlockRange generateBlockRange(const Block& block, const TextRange& textRange); 107 108 ParagraphImpl* fParagraph; 109 TextRange fCurrentText; 110 SkScalar fHeight; 111 bool fUseHalfLeading; 112 SkScalar fBaselineShift; 113 SkVector fAdvance; 114 size_t fUnresolvedGlyphs; 115 size_t fUniqueRunId; 116 117 // TODO: Something that is not thead-safe since we don't need it 118 std::shared_ptr<Run> fCurrentRun; 119 std::deque<RunBlock> fUnresolvedBlocks; 120 std::vector<RunBlock> fResolvedBlocks; 121 122 // Keeping all resolved typefaces 123 struct FontKey { 124 FontKeyFontKey125 FontKey() {} 126 FontKeyFontKey127 FontKey(SkUnichar unicode, SkFontStyle fontStyle, SkString locale) 128 : fUnicode(unicode), fFontStyle(fontStyle), fLocale(locale) { } 129 SkUnichar fUnicode; 130 SkFontStyle fFontStyle; 131 SkString fLocale; 132 133 bool operator==(const FontKey& other) const; 134 135 struct Hasher { 136 uint32_t operator()(const FontKey& key) const; 137 }; 138 }; 139 SkTHashMap<FontKey, sk_sp<SkTypeface>, FontKey::Hasher> fFallbackFonts; 140 }; 141 142 } // namespace textlayout 143 } // namespace skia 144 #endif 145