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 public: 82 virtual ~SkPDFFont(); 83 84 virtual void getResources(const SkTSet<SkPDFObject*>& knownResourceObjects, 85 SkTSet<SkPDFObject*>* newResourceObjects); 86 87 /** Returns the typeface represented by this class. Returns NULL for the 88 * default typeface. 89 */ 90 SkTypeface* typeface(); 91 92 /** Returns the font type represented in this font. For Type0 fonts, 93 * returns the type of the decendant font. 94 */ 95 virtual SkAdvancedTypefaceMetrics::FontType getType(); 96 97 /** Returns true if this font encoding supports glyph IDs above 255. 98 */ 99 virtual bool multiByteGlyphs() const = 0; 100 101 /** Return true if this font has an encoding for the passed glyph id. 102 */ 103 bool hasGlyph(uint16_t glyphID); 104 105 /** Convert (in place) the input glyph IDs into the font encoding. If the 106 * font has more glyphs than can be encoded (like a type 1 font with more 107 * than 255 glyphs) this method only converts up to the first out of range 108 * glyph ID. 109 * @param glyphIDs The input text as glyph IDs. 110 * @param numGlyphs The number of input glyphs. 111 * @return Returns the number of glyphs consumed. 112 */ 113 size_t glyphsToPDFFontEncoding(uint16_t* glyphIDs, size_t numGlyphs); 114 115 /** Get the font resource for the passed typeface and glyphID. The 116 * reference count of the object is incremented and it is the caller's 117 * responsibility to unreference it when done. This is needed to 118 * accommodate the weak reference pattern used when the returned object 119 * is new and has no other references. 120 * @param typeface The typeface to find. 121 * @param glyphID Specify which section of a large font is of interest. 122 */ 123 static SkPDFFont* GetFontResource(SkTypeface* typeface, 124 uint16_t glyphID); 125 126 /** Subset the font based on usage set. Returns a SkPDFFont instance with 127 * subset. 128 * @param usage Glyph subset requested. 129 * @return NULL if font does not support subsetting, a new instance 130 * of SkPDFFont otherwise. 131 */ 132 virtual SkPDFFont* getFontSubset(const SkPDFGlyphSet* usage); 133 134 protected: 135 // Common constructor to handle common members. 136 SkPDFFont(SkAdvancedTypefaceMetrics* fontInfo, SkTypeface* typeface, 137 SkPDFDict* relatedFontDescriptor); 138 139 // Accessors for subclass. 140 SkAdvancedTypefaceMetrics* fontInfo(); 141 void setFontInfo(SkAdvancedTypefaceMetrics* info); 142 uint16_t firstGlyphID() const; 143 uint16_t lastGlyphID() const; 144 void setLastGlyphID(uint16_t glyphID); 145 146 // Add object to resource list. 147 void addResource(SkPDFObject* object); 148 149 // Accessors for FontDescriptor associated with this object. 150 SkPDFDict* getFontDescriptor(); 151 void setFontDescriptor(SkPDFDict* descriptor); 152 153 // Add common entries to FontDescriptor. 154 bool addCommonFontDescriptorEntries(int16_t defaultWidth); 155 156 /** Set fFirstGlyphID and fLastGlyphID to span at most 255 glyphs, 157 * including the passed glyphID. 158 */ 159 void adjustGlyphRangeForSingleByteEncoding(int16_t glyphID); 160 161 // Generate ToUnicode table according to glyph usage subset. 162 // If subset is NULL, all available glyph ids will be used. 163 void populateToUnicodeTable(const SkPDFGlyphSet* subset); 164 165 // Create instances of derived types based on fontInfo. 166 static SkPDFFont* Create(SkAdvancedTypefaceMetrics* fontInfo, 167 SkTypeface* typeface, uint16_t glyphID, 168 SkPDFDict* relatedFontDescriptor); 169 170 static bool Find(uint32_t fontID, uint16_t glyphID, int* index); 171 172 private: 173 class FontRec { 174 public: 175 SkPDFFont* fFont; 176 uint32_t fFontID; 177 uint16_t fGlyphID; 178 179 // A fGlyphID of 0 with no fFont always matches. 180 bool operator==(const FontRec& b) const; 181 FontRec(SkPDFFont* font, uint32_t fontID, uint16_t fGlyphID); 182 }; 183 184 SkAutoTUnref<SkTypeface> fTypeface; 185 186 // The glyph IDs accessible with this font. For Type1 (non CID) fonts, 187 // this will be a subset if the font has more than 255 glyphs. 188 uint16_t fFirstGlyphID; 189 uint16_t fLastGlyphID; 190 // The font info is only kept around after construction for large 191 // Type1 (non CID) fonts that need multiple "fonts" to access all glyphs. 192 SkAutoTUnref<SkAdvancedTypefaceMetrics> fFontInfo; 193 SkTDArray<SkPDFObject*> fResources; 194 SkAutoTUnref<SkPDFDict> fDescriptor; 195 196 SkAdvancedTypefaceMetrics::FontType fFontType; 197 198 // This should be made a hash table if performance is a problem. 199 static SkTDArray<FontRec>& CanonicalFonts(); 200 static SkBaseMutex& CanonicalFontsMutex(); 201 }; 202 203 #endif 204
