1 2 /* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10 #ifndef SkAdvancedTypefaceMetrics_DEFINED 11 #define SkAdvancedTypefaceMetrics_DEFINED 12 13 #include "SkRect.h" 14 #include "SkRefCnt.h" 15 #include "SkString.h" 16 #include "SkTDArray.h" 17 #include "SkTemplates.h" 18 #include "SkTScopedPtr.h" 19 20 /** \class SkAdvancedTypefaceMetrics 21 22 The SkAdvancedTypefaceMetrics class is used by the PDF backend to correctly 23 embed typefaces. This class is filled in with information about a given 24 typeface by the SkFontHost class. 25 */ 26 27 class SkAdvancedTypefaceMetrics : public SkRefCnt { 28 public: 29 SK_DECLARE_INST_COUNT(SkAdvancedTypefaceMetrics) 30 31 SkString fFontName; 32 33 enum FontType { 34 kType1_Font, 35 kType1CID_Font, 36 kCFF_Font, 37 kTrueType_Font, 38 kOther_Font, 39 kNotEmbeddable_Font 40 }; 41 // The type of the underlying font program. This field determines which 42 // of the following fields are valid. If it is kOther_Font or 43 // kNotEmbeddable_Font, the per glyph information will never be populated. 44 FontType fType; 45 46 // fMultiMaster may be true for Type1_Font or CFF_Font. 47 bool fMultiMaster; 48 uint16_t fLastGlyphID; // The last valid glyph ID in the font. 49 uint16_t fEmSize; // The size of the em box (defines font units). 50 51 // These enum values match the values used in the PDF file format. 52 enum StyleFlags { 53 kFixedPitch_Style = 0x00001, 54 kSerif_Style = 0x00002, 55 kSymbolic_Style = 0x00004, 56 kScript_Style = 0x00008, 57 kNonsymbolic_Style = 0x00020, 58 kItalic_Style = 0x00040, 59 kAllCaps_Style = 0x10000, 60 kSmallCaps_Style = 0x20000, 61 kForceBold_Style = 0x40000 62 }; 63 uint16_t fStyle; // Font style characteristics. 64 int16_t fItalicAngle; // Counterclockwise degrees from vertical of the 65 // dominant vertical stroke for an Italic face. 66 // The following fields are all in font units. 67 int16_t fAscent; // Max height above baseline, not including accents. 68 int16_t fDescent; // Max depth below baseline (negative). 69 int16_t fStemV; // Thickness of dominant vertical stem. 70 int16_t fCapHeight; // Height (from baseline) of top of flat capitals. 71 72 SkIRect fBBox; // The bounding box of all glyphs (in font units). 73 74 // The type of advance data wanted. 75 enum PerGlyphInfo { 76 kNo_PerGlyphInfo = 0x0, // Don't populate any per glyph info. 77 kHAdvance_PerGlyphInfo = 0x1, // Populate horizontal advance data. 78 kVAdvance_PerGlyphInfo = 0x2, // Populate vertical advance data. 79 kGlyphNames_PerGlyphInfo = 0x4, // Populate glyph names (Type 1 only). 80 kToUnicode_PerGlyphInfo = 0x8 // Populate ToUnicode table, ignored 81 // for Type 1 fonts 82 }; 83 84 template <typename Data> 85 struct AdvanceMetric { 86 enum MetricType { 87 kDefault, // Default advance: fAdvance.count = 1 88 kRange, // Advances for a range: fAdvance.count = fEndID-fStartID 89 kRun // fStartID-fEndID have same advance: fAdvance.count = 1 90 }; 91 MetricType fType; 92 uint16_t fStartId; 93 uint16_t fEndId; 94 SkTDArray<Data> fAdvance; 95 SkTScopedPtr<AdvanceMetric<Data> > fNext; 96 }; 97 98 struct VerticalMetric { 99 int16_t fVerticalAdvance; 100 int16_t fOriginXDisp; // Horiz. displacement of the secondary origin. 101 int16_t fOriginYDisp; // Vert. displacement of the secondary origin. 102 }; 103 typedef AdvanceMetric<int16_t> WidthRange; 104 typedef AdvanceMetric<VerticalMetric> VerticalAdvanceRange; 105 106 // This is indexed by glyph id. 107 SkTScopedPtr<WidthRange> fGlyphWidths; 108 // Only used for Vertical CID fonts. 109 SkTScopedPtr<VerticalAdvanceRange> fVerticalMetrics; 110 111 // The names of each glyph, only populated for postscript fonts. 112 SkTScopedPtr<SkAutoTArray<SkString> > fGlyphNames; 113 114 // The mapping from glyph to Unicode, only populated if 115 // kToUnicode_PerGlyphInfo is passed to GetAdvancedTypefaceMetrics. 116 SkTDArray<SkUnichar> fGlyphToUnicode; 117 118 private: 119 typedef SkRefCnt INHERITED; 120 }; 121 122 namespace skia_advanced_typeface_metrics_utils { 123 124 template <typename Data> 125 void resetRange(SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* range, 126 int startId); 127 128 template <typename Data> 129 SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* appendRange( 130 SkTScopedPtr<SkAdvancedTypefaceMetrics::AdvanceMetric<Data> >* nextSlot, 131 int startId); 132 133 template <typename Data> 134 void finishRange( 135 SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* range, 136 int endId, 137 typename SkAdvancedTypefaceMetrics::AdvanceMetric<Data>::MetricType 138 type); 139 140 /** Retrieve advance data for glyphs. Used by the PDF backend. It calls 141 underlying platform dependent API getAdvance to acquire the data. 142 @param num_glyphs Total number of glyphs in the given font. 143 @param glyphIDs For per-glyph info, specify subset of the font by 144 giving glyph ids. Each integer represents a glyph 145 id. Passing NULL means all glyphs in the font. 146 @param glyphIDsCount Number of elements in subsetGlyphIds. Ignored if 147 glyphIDs is NULL. 148 */ 149 template <typename Data, typename FontHandle> 150 SkAdvancedTypefaceMetrics::AdvanceMetric<Data>* getAdvanceData( 151 FontHandle fontHandle, 152 int num_glyphs, 153 const uint32_t* glyphIDs, 154 uint32_t glyphIDsCount, 155 bool (*getAdvance)(FontHandle fontHandle, int gId, Data* data)); 156 157 } // namespace skia_advanced_typeface_metrics_utils 158 159 #endif 160
