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 SkPDFFont_DEFINED 11 #define SkPDFFont_DEFINED 12 13 #include "SkAdvancedTypefaceMetrics.h" 14 #include "SkBitSet.h" 15 #include "SkPDFTypes.h" 16 #include "SkTDArray.h" 17 #include "SkThread.h" 18 #include "SkTypeface.h" 19 20 class SkPaint; 21 class SkPDFCatalog; 22 class SkPDFFont; 23 24 class SkPDFGlyphSet : public SkNoncopyable { 25 public: 26 SkPDFGlyphSet(); 27 28 void set(const uint16_t* glyphIDs, int numGlyphs); 29 bool has(uint16_t glyphID) const; 30 void merge(const SkPDFGlyphSet& usage); 31 void exportTo(SkTDArray<uint32_t>* glyphIDs) const; 32 33 private: 34 SkBitSet fBitSet; 35 }; 36 37 class SkPDFGlyphSetMap : public SkNoncopyable { 38 public: 39 struct FontGlyphSetPair { 40 FontGlyphSetPair(SkPDFFont* font, SkPDFGlyphSet* glyphSet); 41 42 SkPDFFont* fFont; 43 SkPDFGlyphSet* fGlyphSet; 44 }; 45 46 SkPDFGlyphSetMap(); 47 ~SkPDFGlyphSetMap(); 48 49 class F2BIter { 50 public: 51 explicit F2BIter(const SkPDFGlyphSetMap& map); 52 const FontGlyphSetPair* next() const; 53 void reset(const SkPDFGlyphSetMap& map); 54 55 private: 56 const SkTDArray<FontGlyphSetPair>* fMap; 57 mutable int fIndex; 58 }; 59 60 void merge(const SkPDFGlyphSetMap& usage); 61 void reset(); 62 63 void noteGlyphUsage(SkPDFFont* font, const uint16_t* glyphIDs, 64 int numGlyphs); 65 66 private: 67 SkPDFGlyphSet* getGlyphSetForFont(SkPDFFont* font); 68 69 SkTDArray<FontGlyphSetPair> fMap; 70 }; 71 72 73 /** \class SkPDFFont 74 A PDF Object class representing a font. The font may have resources 75 attached to it in order to embed the font. SkPDFFonts are canonicalized 76 so that resource deduplication will only include one copy of a font. 77 This class uses the same pattern as SkPDFGraphicState, a static weak 78 reference to each instantiated class. 79 */ 80 class SkPDFFont : public SkPDFDict { 81 SK_DECLARE_INST_COUNT(SkPDFFont) 82 public: 83 virtual ~SkPDFFont(); 84 85 virtual void getResources(const SkTSet<SkPDFObject*>& knownResourceObjects, 86 SkTSet<SkPDFObject*>* newResourceObjects); 87 88 /** Returns the typeface represented by this class. Returns NULL for the 89 * default typeface. 90 */ 91 SkTypeface* typeface(); 92 93 /** Returns the font type represented in this font. For Type0 fonts, 94 * returns the type of the decendant font. 95 */ 96 virtual SkAdvancedTypefaceMetrics::FontType getType(); 97 98 /** Returns true if this font encoding supports glyph IDs above 255. 99 */ 100 virtual bool multiByteGlyphs() const = 0; 101 102 /** Return true if this font has an encoding for the passed glyph id. 103 */ 104 bool hasGlyph(uint16_t glyphID); 105 106 /** Convert (in place) the input glyph IDs into the font encoding. If the 107 * font has more glyphs than can be encoded (like a type 1 font with more 108 * than 255 glyphs) this method only converts up to the first out of range 109 * glyph ID. 110 * @param glyphIDs The input text as glyph IDs. 111 * @param numGlyphs The number of input glyphs. 112 * @return Returns the number of glyphs consumed. 113 */ 114 size_t glyphsToPDFFontEncoding(uint16_t* glyphIDs, size_t numGlyphs); 115 116 /** Get the font resource for the passed typeface and glyphID. The 117 * reference count of the object is incremented and it is the caller's 118 * responsibility to unreference it when done. This is needed to 119 * accommodate the weak reference pattern used when the returned object 120 * is new and has no other references. 121 * @param typeface The typeface to find. 122 * @param glyphID Specify which section of a large font is of interest. 123 */ 124 static SkPDFFont* GetFontResource(SkTypeface* typeface, 125 uint16_t glyphID); 126 127 /** Subset the font based on usage set. Returns a SkPDFFont instance with 128 * subset. 129 * @param usage Glyph subset requested. 130 * @return NULL if font does not support subsetting, a new instance 131 * of SkPDFFont otherwise. 132 */ 133 virtual SkPDFFont* getFontSubset(const SkPDFGlyphSet* usage); 134 135 protected: 136 // Common constructor to handle common members. 137 SkPDFFont(SkAdvancedTypefaceMetrics* fontInfo, SkTypeface* typeface, 138 SkPDFDict* relatedFontDescriptor); 139 140 // Accessors for subclass. 141 SkAdvancedTypefaceMetrics* fontInfo(); 142 void setFontInfo(SkAdvancedTypefaceMetrics* info); 143 uint16_t firstGlyphID() const; 144 uint16_t lastGlyphID() const; 145 void setLastGlyphID(uint16_t glyphID); 146 147 // Add object to resource list. 148 void addResource(SkPDFObject* object); 149 150 // Accessors for FontDescriptor associated with this object. 151 SkPDFDict* getFontDescriptor(); 152 void setFontDescriptor(SkPDFDict* descriptor); 153 154 // Add common entries to FontDescriptor. 155 bool addCommonFontDescriptorEntries(int16_t defaultWidth); 156 157 /** Set fFirstGlyphID and fLastGlyphID to span at most 255 glyphs, 158 * including the passed glyphID. 159 */ 160 void adjustGlyphRangeForSingleByteEncoding(int16_t glyphID); 161 162 // Generate ToUnicode table according to glyph usage subset. 163 // If subset is NULL, all available glyph ids will be used. 164 void populateToUnicodeTable(const SkPDFGlyphSet* subset); 165 166 // Create instances of derived types based on fontInfo. 167 static SkPDFFont* Create(SkAdvancedTypefaceMetrics* fontInfo, 168 SkTypeface* typeface, uint16_t glyphID, 169 SkPDFDict* relatedFontDescriptor); 170 171 static bool Find(uint32_t fontID, uint16_t glyphID, int* index); 172 173 private: 174 class FontRec { 175 public: 176 SkPDFFont* fFont; 177 uint32_t fFontID; 178 uint16_t fGlyphID; 179 180 // A fGlyphID of 0 with no fFont always matches. 181 bool operator==(const FontRec& b) const; 182 FontRec(SkPDFFont* font, uint32_t fontID, uint16_t fGlyphID); 183 }; 184 185 SkAutoTUnref<SkTypeface> fTypeface; 186 187 // The glyph IDs accessible with this font. For Type1 (non CID) fonts, 188 // this will be a subset if the font has more than 255 glyphs. 189 uint16_t fFirstGlyphID; 190 uint16_t fLastGlyphID; 191 // The font info is only kept around after construction for large 192 // Type1 (non CID) fonts that need multiple "fonts" to access all glyphs. 193 SkAutoTUnref<SkAdvancedTypefaceMetrics> fFontInfo; 194 SkTDArray<SkPDFObject*> fResources; 195 SkAutoTUnref<SkPDFDict> fDescriptor; 196 197 SkAdvancedTypefaceMetrics::FontType fFontType; 198 199 // This should be made a hash table if performance is a problem. 200 static SkTDArray<FontRec>& CanonicalFonts(); 201 static SkBaseMutex& CanonicalFontsMutex(); 202 typedef SkPDFDict INHERITED; 203 }; 204 205 #endif 206
