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31 #ifndef HarfBuzzShaper_h
32 #define HarfBuzzShaper_h
35 #include "platform/fonts/GlyphBuffer.h"
36 #include "platform/geometry/FloatPoint.h"
37 #include "platform/text/TextRun.h"
38 #include "wtf/HashSet.h"
39 #include "wtf/OwnPtr.h"
40 #include "wtf/PassOwnPtr.h"
41 #include "wtf/unicode/CharacterNames.h"
42 #include "wtf/Vector.h"
49 class HarfBuzzShaper FINAL {
52 DoNotNormalizeMirrorChars,
56 HarfBuzzShaper(const Font*, const TextRun&);
58 void setDrawRange(int from, int to);
59 bool shape(GlyphBuffer* = 0);
60 FloatPoint adjustStartPoint(const FloatPoint&);
61 float totalWidth() { return m_totalWidth; }
62 int offsetForPosition(float targetX);
63 FloatRect selectionRect(const FloatPoint&, int height, int from, int to);
68 HarfBuzzRun(const HarfBuzzRun&);
71 static PassOwnPtr<HarfBuzzRun> create(const SimpleFontData* fontData, unsigned startIndex, unsigned numCharacters, TextDirection direction, hb_script_t script)
73 return adoptPtr(new HarfBuzzRun(fontData, startIndex, numCharacters, direction, script));
76 void applyShapeResult(hb_buffer_t*);
77 void copyShapeResultAndGlyphPositions(const HarfBuzzRun&);
78 void setGlyphAndPositions(unsigned index, uint16_t glyphId, float advance, float offsetX, float offsetY);
79 void setWidth(float width) { m_width = width; }
81 int characterIndexForXPosition(float targetX);
82 float xPositionForOffset(unsigned offset);
84 const SimpleFontData* fontData() { return m_fontData; }
85 unsigned startIndex() const { return m_startIndex; }
86 unsigned numCharacters() const { return m_numCharacters; }
87 unsigned numGlyphs() const { return m_numGlyphs; }
88 uint16_t* glyphs() { return &m_glyphs[0]; }
89 float* advances() { return &m_advances[0]; }
90 FloatPoint* offsets() { return &m_offsets[0]; }
91 bool hasGlyphToCharacterIndexes() const
93 return m_glyphToCharacterIndexes.size() > 0;
95 uint16_t* glyphToCharacterIndexes()
97 return &m_glyphToCharacterIndexes[0];
99 float width() { return m_width; }
100 bool rtl() { return m_direction == RTL; }
101 hb_script_t script() { return m_script; }
104 HarfBuzzRun(const SimpleFontData*, unsigned startIndex, unsigned numCharacters, TextDirection, hb_script_t);
106 const SimpleFontData* m_fontData;
107 unsigned m_startIndex;
108 size_t m_numCharacters;
109 unsigned m_numGlyphs;
110 TextDirection m_direction;
111 hb_script_t m_script;
112 Vector<uint16_t, 256> m_glyphs;
113 Vector<float, 256> m_advances;
114 Vector<uint16_t, 256> m_glyphToCharacterIndexes;
115 Vector<FloatPoint, 256> m_offsets;
119 void setNormalizedBuffer(NormalizeMode = DoNotNormalizeMirrorChars);
121 bool isWordEnd(unsigned);
122 int determineWordBreakSpacing();
123 // setPadding sets a number of pixels to be distributed across the TextRun.
124 // WebKit uses this to justify text.
125 void setPadding(int);
127 // In complex text word-spacing affects each line-break, space (U+0020) and non-breaking space (U+00A0).
128 static bool isCodepointSpace(UChar c) { return c == ' ' || c == noBreakSpace || c == '\n'; }
130 void setFontFeatures();
132 bool createHarfBuzzRuns();
133 bool shapeHarfBuzzRuns();
134 bool fillGlyphBuffer(GlyphBuffer*);
135 void fillGlyphBufferFromHarfBuzzRun(GlyphBuffer*, HarfBuzzRun*, FloatPoint& firstOffsetOfNextRun);
136 void setGlyphPositionsForHarfBuzzRun(HarfBuzzRun*, hb_buffer_t*);
137 void addHarfBuzzRun(unsigned startCharacter, unsigned endCharacter, const SimpleFontData*, UScriptCode);
139 GlyphBufferAdvance createGlyphBufferAdvance(float, float);
142 OwnPtr<UChar[]> m_normalizedBuffer;
143 unsigned m_normalizedBufferLength;
144 const TextRun& m_run;
146 float m_wordSpacingAdjustment; // Delta adjustment (pixels) for each word break.
147 float m_padding; // Pixels to be distributed over the line at word breaks.
148 float m_padPerWordBreak; // Pixels to be added to each word break.
149 float m_padError; // m_padPerWordBreak might have a fractional component. Since we only add a whole number of padding pixels at each word break we accumulate error. This is the number of pixels that we are behind so far.
150 float m_letterSpacing; // Pixels to be added after each glyph.
152 Vector<hb_feature_t, 4> m_features;
153 Vector<OwnPtr<HarfBuzzRun>, 16> m_harfBuzzRuns;
155 FloatPoint m_startOffset;
162 friend struct CachedShapingResults;
165 } // namespace WebCore
167 #endif // HarfBuzzShaper_h