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