1 /***************************************************************************/ 2 /* */ 3 /* cf2hints.h */ 4 /* */ 5 /* Adobe's code for handling CFF hints (body). */ 6 /* */ 7 /* Copyright 2007-2013 Adobe Systems Incorporated. */ 8 /* */ 9 /* This software, and all works of authorship, whether in source or */ 10 /* object code form as indicated by the copyright notice(s) included */ 11 /* herein (collectively, the "Work") is made available, and may only be */ 12 /* used, modified, and distributed under the FreeType Project License, */ 13 /* LICENSE.TXT. Additionally, subject to the terms and conditions of the */ 14 /* FreeType Project License, each contributor to the Work hereby grants */ 15 /* to any individual or legal entity exercising permissions granted by */ 16 /* the FreeType Project License and this section (hereafter, "You" or */ 17 /* "Your") a perpetual, worldwide, non-exclusive, no-charge, */ 18 /* royalty-free, irrevocable (except as stated in this section) patent */ 19 /* license to make, have made, use, offer to sell, sell, import, and */ 20 /* otherwise transfer the Work, where such license applies only to those */ 21 /* patent claims licensable by such contributor that are necessarily */ 22 /* infringed by their contribution(s) alone or by combination of their */ 23 /* contribution(s) with the Work to which such contribution(s) was */ 24 /* submitted. If You institute patent litigation against any entity */ 25 /* (including a cross-claim or counterclaim in a lawsuit) alleging that */ 26 /* the Work or a contribution incorporated within the Work constitutes */ 27 /* direct or contributory patent infringement, then any patent licenses */ 28 /* granted to You under this License for that Work shall terminate as of */ 29 /* the date such litigation is filed. */ 30 /* */ 31 /* By using, modifying, or distributing the Work you indicate that you */ 32 /* have read and understood the terms and conditions of the */ 33 /* FreeType Project License as well as those provided in this section, */ 34 /* and you accept them fully. */ 35 /* */ 36 /***************************************************************************/ 37 38 39 #ifndef CF2HINTS_H_ 40 #define CF2HINTS_H_ 41 42 43 FT_BEGIN_HEADER 44 45 46 enum 47 { 48 CF2_MAX_HINTS = 96 /* maximum # of hints */ 49 }; 50 51 52 /* 53 * A HintMask object stores a bit mask that specifies which hints in the 54 * charstring are active at a given time. Hints in CFF must be declared 55 * at the start, before any drawing operators, with horizontal hints 56 * preceding vertical hints. The HintMask is ordered the same way, with 57 * horizontal hints immediately followed by vertical hints. Clients are 58 * responsible for knowing how many of each type are present. 59 * 60 * The maximum total number of hints is 96, as specified by the CFF 61 * specification. 62 * 63 * A HintMask is built 0 or more times while interpreting a charstring, by 64 * the HintMask operator. There is only one HintMask, but it is built or 65 * rebuilt each time there is a hint substitution (HintMask operator) in 66 * the charstring. A default HintMask with all bits set is built if there 67 * has been no HintMask operator prior to the first drawing operator. 68 * 69 */ 70 71 typedef struct CF2_HintMaskRec_ 72 { 73 FT_Error* error; 74 75 FT_Bool isValid; 76 FT_Bool isNew; 77 78 size_t bitCount; 79 size_t byteCount; 80 81 FT_Byte mask[( CF2_MAX_HINTS + 7 ) / 8]; 82 83 } CF2_HintMaskRec, *CF2_HintMask; 84 85 86 typedef struct CF2_StemHintRec_ 87 { 88 FT_Bool used; /* DS positions are valid */ 89 90 CF2_Fixed min; /* original character space value */ 91 CF2_Fixed max; 92 93 CF2_Fixed minDS; /* DS position after first use */ 94 CF2_Fixed maxDS; 95 96 } CF2_StemHintRec, *CF2_StemHint; 97 98 99 /* 100 * A HintMap object stores a piecewise linear function for mapping 101 * y-coordinates from character space to device space, providing 102 * appropriate pixel alignment to stem edges. 103 * 104 * The map is implemented as an array of `CF2_Hint' elements, each 105 * representing an edge. When edges are paired, as from stem hints, the 106 * bottom edge must immediately precede the top edge in the array. 107 * Element character space AND device space positions must both increase 108 * monotonically in the array. `CF2_Hint' elements are also used as 109 * parameters to `cf2_blues_capture'. 110 * 111 * The `cf2_hintmap_build' method must be called before any drawing 112 * operation (beginning with a Move operator) and at each hint 113 * substitution (HintMask operator). 114 * 115 * The `cf2_hintmap_map' method is called to transform y-coordinates at 116 * each drawing operation (move, line, curve). 117 * 118 */ 119 120 /* TODO: make this a CF2_ArrStack and add a deep copy method */ 121 enum 122 { 123 CF2_MAX_HINT_EDGES = CF2_MAX_HINTS * 2 124 }; 125 126 127 typedef struct CF2_HintMapRec_ 128 { 129 CF2_Font font; 130 131 /* initial map based on blue zones */ 132 struct CF2_HintMapRec_* initialHintMap; 133 134 /* working storage for 2nd pass adjustHints */ 135 CF2_ArrStack hintMoves; 136 137 FT_Bool isValid; 138 FT_Bool hinted; 139 140 CF2_Fixed scale; 141 CF2_UInt count; 142 143 /* start search from this index */ 144 CF2_UInt lastIndex; 145 146 CF2_HintRec edge[CF2_MAX_HINT_EDGES]; /* 192 */ 147 148 } CF2_HintMapRec, *CF2_HintMap; 149 150 151 FT_LOCAL( FT_Bool ) 152 cf2_hint_isValid( const CF2_Hint hint ); 153 FT_LOCAL( FT_Bool ) 154 cf2_hint_isTop( const CF2_Hint hint ); 155 FT_LOCAL( FT_Bool ) 156 cf2_hint_isBottom( const CF2_Hint hint ); 157 FT_LOCAL( void ) 158 cf2_hint_lock( CF2_Hint hint ); 159 160 161 FT_LOCAL( void ) 162 cf2_hintmap_init( CF2_HintMap hintmap, 163 CF2_Font font, 164 CF2_HintMap initialMap, 165 CF2_ArrStack hintMoves, 166 CF2_Fixed scale ); 167 FT_LOCAL( void ) 168 cf2_hintmap_build( CF2_HintMap hintmap, 169 CF2_ArrStack hStemHintArray, 170 CF2_ArrStack vStemHintArray, 171 CF2_HintMask hintMask, 172 CF2_Fixed hintOrigin, 173 FT_Bool initialMap ); 174 175 176 /* 177 * GlyphPath is a wrapper for drawing operations that scales the 178 * coordinates according to the render matrix and HintMap. It also tracks 179 * open paths to control ClosePath and to insert MoveTo for broken fonts. 180 * 181 */ 182 typedef struct CF2_GlyphPathRec_ 183 { 184 /* TODO: gather some of these into a hinting context */ 185 186 CF2_Font font; /* font instance */ 187 CF2_OutlineCallbacks callbacks; /* outline consumer */ 188 189 190 CF2_HintMapRec hintMap; /* current hint map */ 191 CF2_HintMapRec firstHintMap; /* saved copy */ 192 CF2_HintMapRec initialHintMap; /* based on all captured hints */ 193 194 CF2_ArrStackRec hintMoves; /* list of hint moves for 2nd pass */ 195 196 CF2_Fixed scaleX; /* matrix a */ 197 CF2_Fixed scaleC; /* matrix c */ 198 CF2_Fixed scaleY; /* matrix d */ 199 200 FT_Vector fractionalTranslation; /* including deviceXScale */ 201 #if 0 202 CF2_Fixed hShift; /* character space horizontal shift */ 203 /* (for fauxing) */ 204 #endif 205 206 FT_Bool pathIsOpen; /* true after MoveTo */ 207 FT_Bool pathIsClosing; /* true when synthesizing closepath line */ 208 FT_Bool darken; /* true if stem darkening */ 209 FT_Bool moveIsPending; /* true between MoveTo and offset MoveTo */ 210 211 /* references used to call `cf2_hintmap_build', if necessary */ 212 CF2_ArrStack hStemHintArray; 213 CF2_ArrStack vStemHintArray; 214 CF2_HintMask hintMask; /* ptr to the current mask */ 215 CF2_Fixed hintOriginY; /* copy of current origin */ 216 const CF2_BluesRec* blues; 217 218 CF2_Fixed xOffset; /* character space offsets */ 219 CF2_Fixed yOffset; 220 221 /* character space miter limit threshold */ 222 CF2_Fixed miterLimit; 223 /* vertical/horizontal snap distance in character space */ 224 CF2_Fixed snapThreshold; 225 226 FT_Vector offsetStart0; /* first and second points of first */ 227 FT_Vector offsetStart1; /* element with offset applied */ 228 229 /* current point, character space, before offset */ 230 FT_Vector currentCS; 231 /* current point, device space */ 232 FT_Vector currentDS; 233 /* start point of subpath, character space */ 234 FT_Vector start; 235 236 /* the following members constitute the `queue' of one element */ 237 FT_Bool elemIsQueued; 238 CF2_Int prevElemOp; 239 240 FT_Vector prevElemP0; 241 FT_Vector prevElemP1; 242 FT_Vector prevElemP2; 243 FT_Vector prevElemP3; 244 245 } CF2_GlyphPathRec, *CF2_GlyphPath; 246 247 248 FT_LOCAL( void ) 249 cf2_glyphpath_init( CF2_GlyphPath glyphpath, 250 CF2_Font font, 251 CF2_OutlineCallbacks callbacks, 252 CF2_Fixed scaleY, 253 /* CF2_Fixed hShift, */ 254 CF2_ArrStack hStemHintArray, 255 CF2_ArrStack vStemHintArray, 256 CF2_HintMask hintMask, 257 CF2_Fixed hintOrigin, 258 const CF2_Blues blues, 259 const FT_Vector* fractionalTranslation ); 260 FT_LOCAL( void ) 261 cf2_glyphpath_finalize( CF2_GlyphPath glyphpath ); 262 263 FT_LOCAL( void ) 264 cf2_glyphpath_moveTo( CF2_GlyphPath glyphpath, 265 CF2_Fixed x, 266 CF2_Fixed y ); 267 FT_LOCAL( void ) 268 cf2_glyphpath_lineTo( CF2_GlyphPath glyphpath, 269 CF2_Fixed x, 270 CF2_Fixed y ); 271 FT_LOCAL( void ) 272 cf2_glyphpath_curveTo( CF2_GlyphPath glyphpath, 273 CF2_Fixed x1, 274 CF2_Fixed y1, 275 CF2_Fixed x2, 276 CF2_Fixed y2, 277 CF2_Fixed x3, 278 CF2_Fixed y3 ); 279 FT_LOCAL( void ) 280 cf2_glyphpath_closeOpenPath( CF2_GlyphPath glyphpath ); 281 282 283 FT_END_HEADER 284 285 286 #endif /* CF2HINTS_H_ */ 287 288 289 /* END */ 290