1 /***************************************************************************/ 2 /* */ 3 /* aftypes.h */ 4 /* */ 5 /* Auto-fitter types (specification only). */ 6 /* */ 7 /* Copyright 2003, 2004, 2005, 2006, 2007, 2008, 2009 by */ 8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 9 /* */ 10 /* This file is part of the FreeType project, and may only be used, */ 11 /* modified, and distributed under the terms of the FreeType project */ 12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 13 /* this file you indicate that you have read the license and */ 14 /* understand and accept it fully. */ 15 /* */ 16 /***************************************************************************/ 17 18 19 /************************************************************************* 20 * 21 * The auto-fitter is a complete rewrite of the old auto-hinter. 22 * Its main feature is the ability to differentiate between different 23 * scripts in order to apply language-specific rules. 24 * 25 * The code has also been compartmentized into several entities that 26 * should make algorithmic experimentation easier than with the old 27 * code. 28 * 29 * Finally, we get rid of the Catharon license, since this code is 30 * released under the FreeType one. 31 * 32 *************************************************************************/ 33 34 35 #ifndef __AFTYPES_H__ 36 #define __AFTYPES_H__ 37 38 #include <ft2build.h> 39 40 #include FT_FREETYPE_H 41 #include FT_OUTLINE_H 42 #include FT_INTERNAL_OBJECTS_H 43 #include FT_INTERNAL_DEBUG_H 44 45 46 FT_BEGIN_HEADER 47 48 /*************************************************************************/ 49 /*************************************************************************/ 50 /***** *****/ 51 /***** D E B U G G I N G *****/ 52 /***** *****/ 53 /*************************************************************************/ 54 /*************************************************************************/ 55 56 #define xxAF_USE_WARPER /* only define to use warp hinting */ 57 #define xxAF_DEBUG 58 59 #ifdef AF_DEBUG 60 61 #include FT_CONFIG_STANDARD_LIBRARY_H 62 63 #define AF_LOG( x ) do { if ( _af_debug ) printf x; } while ( 0 ) 64 65 extern int _af_debug; 66 extern int _af_debug_disable_horz_hints; 67 extern int _af_debug_disable_vert_hints; 68 extern int _af_debug_disable_blue_hints; 69 extern void* _af_debug_hints; 70 71 #else /* !AF_DEBUG */ 72 73 #define AF_LOG( x ) do { } while ( 0 ) /* nothing */ 74 75 #endif /* !AF_DEBUG */ 76 77 78 /*************************************************************************/ 79 /*************************************************************************/ 80 /***** *****/ 81 /***** U T I L I T Y S T U F F *****/ 82 /***** *****/ 83 /*************************************************************************/ 84 /*************************************************************************/ 85 86 typedef struct AF_WidthRec_ 87 { 88 FT_Pos org; /* original position/width in font units */ 89 FT_Pos cur; /* current/scaled position/width in device sub-pixels */ 90 FT_Pos fit; /* current/fitted position/width in device sub-pixels */ 91 92 } AF_WidthRec, *AF_Width; 93 94 95 FT_LOCAL( void ) 96 af_sort_pos( FT_UInt count, 97 FT_Pos* table ); 98 99 FT_LOCAL( void ) 100 af_sort_widths( FT_UInt count, 101 AF_Width widths ); 102 103 104 /*************************************************************************/ 105 /*************************************************************************/ 106 /***** *****/ 107 /***** A N G L E T Y P E S *****/ 108 /***** *****/ 109 /*************************************************************************/ 110 /*************************************************************************/ 111 112 /* 113 * The auto-fitter doesn't need a very high angular accuracy; 114 * this allows us to speed up some computations considerably with a 115 * light Cordic algorithm (see afangles.c). 116 */ 117 118 typedef FT_Int AF_Angle; 119 120 121 #define AF_ANGLE_PI 256 122 #define AF_ANGLE_2PI ( AF_ANGLE_PI * 2 ) 123 #define AF_ANGLE_PI2 ( AF_ANGLE_PI / 2 ) 124 #define AF_ANGLE_PI4 ( AF_ANGLE_PI / 4 ) 125 126 127 #if 0 128 /* 129 * compute the angle of a given 2-D vector 130 */ 131 FT_LOCAL( AF_Angle ) 132 af_angle_atan( FT_Pos dx, 133 FT_Pos dy ); 134 135 136 /* 137 * compute `angle2 - angle1'; the result is always within 138 * the range [-AF_ANGLE_PI .. AF_ANGLE_PI - 1] 139 */ 140 FT_LOCAL( AF_Angle ) 141 af_angle_diff( AF_Angle angle1, 142 AF_Angle angle2 ); 143 #endif /* 0 */ 144 145 146 #define AF_ANGLE_DIFF( result, angle1, angle2 ) \ 147 FT_BEGIN_STMNT \ 148 AF_Angle _delta = (angle2) - (angle1); \ 149 \ 150 \ 151 _delta %= AF_ANGLE_2PI; \ 152 if ( _delta < 0 ) \ 153 _delta += AF_ANGLE_2PI; \ 154 \ 155 if ( _delta > AF_ANGLE_PI ) \ 156 _delta -= AF_ANGLE_2PI; \ 157 \ 158 result = _delta; \ 159 FT_END_STMNT 160 161 162 /*************************************************************************/ 163 /*************************************************************************/ 164 /***** *****/ 165 /***** O U T L I N E S *****/ 166 /***** *****/ 167 /*************************************************************************/ 168 /*************************************************************************/ 169 170 /* opaque handle to glyph-specific hints -- see `afhints.h' for more 171 * details 172 */ 173 typedef struct AF_GlyphHintsRec_* AF_GlyphHints; 174 175 /* This structure is used to model an input glyph outline to 176 * the auto-hinter. The latter will set the `hints' field 177 * depending on the glyph's script. 178 */ 179 typedef struct AF_OutlineRec_ 180 { 181 FT_Face face; 182 FT_Outline outline; 183 FT_UInt outline_resolution; 184 185 FT_Int advance; 186 FT_UInt metrics_resolution; 187 188 AF_GlyphHints hints; 189 190 } AF_OutlineRec; 191 192 193 /*************************************************************************/ 194 /*************************************************************************/ 195 /***** *****/ 196 /***** S C A L E R S *****/ 197 /***** *****/ 198 /*************************************************************************/ 199 /*************************************************************************/ 200 201 /* 202 * A scaler models the target pixel device that will receive the 203 * auto-hinted glyph image. 204 */ 205 206 typedef enum AF_ScalerFlags_ 207 { 208 AF_SCALER_FLAG_NO_HORIZONTAL = 1, /* disable horizontal hinting */ 209 AF_SCALER_FLAG_NO_VERTICAL = 2, /* disable vertical hinting */ 210 AF_SCALER_FLAG_NO_ADVANCE = 4 /* disable advance hinting */ 211 212 } AF_ScalerFlags; 213 214 215 typedef struct AF_ScalerRec_ 216 { 217 FT_Face face; /* source font face */ 218 FT_Fixed x_scale; /* from font units to 1/64th device pixels */ 219 FT_Fixed y_scale; /* from font units to 1/64th device pixels */ 220 FT_Pos x_delta; /* in 1/64th device pixels */ 221 FT_Pos y_delta; /* in 1/64th device pixels */ 222 FT_Render_Mode render_mode; /* monochrome, anti-aliased, LCD, etc. */ 223 FT_UInt32 flags; /* additional control flags, see above */ 224 225 } AF_ScalerRec, *AF_Scaler; 226 227 228 #define AF_SCALER_EQUAL_SCALES( a, b ) \ 229 ( (a)->x_scale == (b)->x_scale && \ 230 (a)->y_scale == (b)->y_scale && \ 231 (a)->x_delta == (b)->x_delta && \ 232 (a)->y_delta == (b)->y_delta ) 233 234 235 /*************************************************************************/ 236 /*************************************************************************/ 237 /***** *****/ 238 /***** S C R I P T S *****/ 239 /***** *****/ 240 /*************************************************************************/ 241 /*************************************************************************/ 242 243 /* 244 * The list of know scripts. Each different script corresponds to the 245 * following information: 246 * 247 * - A set of Unicode ranges to test whether the face supports the 248 * script. 249 * 250 * - A specific global analyzer that will compute global metrics 251 * specific to the script. 252 * 253 * - A specific glyph analyzer that will compute segments and 254 * edges for each glyph covered by the script. 255 * 256 * - A specific grid-fitting algorithm that will distort the 257 * scaled glyph outline according to the results of the glyph 258 * analyzer. 259 * 260 * Note that a given analyzer and/or grid-fitting algorithm can be 261 * used by more than one script. 262 */ 263 264 typedef enum AF_Script_ 265 { 266 AF_SCRIPT_NONE = 0, 267 AF_SCRIPT_LATIN = 1, 268 AF_SCRIPT_CJK = 2, 269 AF_SCRIPT_INDIC = 3, 270 #ifdef FT_OPTION_AUTOFIT2 271 AF_SCRIPT_LATIN2, 272 #endif 273 274 /* add new scripts here. Don't forget to update the list in */ 275 /* `afglobal.c'. */ 276 277 AF_SCRIPT_MAX /* do not remove */ 278 279 } AF_Script; 280 281 282 typedef struct AF_ScriptClassRec_ const* AF_ScriptClass; 283 284 typedef struct AF_ScriptMetricsRec_ 285 { 286 AF_ScriptClass clazz; 287 AF_ScalerRec scaler; 288 289 } AF_ScriptMetricsRec, *AF_ScriptMetrics; 290 291 292 /* This function parses an FT_Face to compute global metrics for 293 * a specific script. 294 */ 295 typedef FT_Error 296 (*AF_Script_InitMetricsFunc)( AF_ScriptMetrics metrics, 297 FT_Face face ); 298 299 typedef void 300 (*AF_Script_ScaleMetricsFunc)( AF_ScriptMetrics metrics, 301 AF_Scaler scaler ); 302 303 typedef void 304 (*AF_Script_DoneMetricsFunc)( AF_ScriptMetrics metrics ); 305 306 307 typedef FT_Error 308 (*AF_Script_InitHintsFunc)( AF_GlyphHints hints, 309 AF_ScriptMetrics metrics ); 310 311 typedef void 312 (*AF_Script_ApplyHintsFunc)( AF_GlyphHints hints, 313 FT_Outline* outline, 314 AF_ScriptMetrics metrics ); 315 316 317 typedef struct AF_Script_UniRangeRec_ 318 { 319 FT_UInt32 first; 320 FT_UInt32 last; 321 322 } AF_Script_UniRangeRec; 323 324 typedef const AF_Script_UniRangeRec *AF_Script_UniRange; 325 326 327 typedef struct AF_ScriptClassRec_ 328 { 329 AF_Script script; 330 AF_Script_UniRange script_uni_ranges; /* last must be { 0, 0 } */ 331 332 FT_UInt script_metrics_size; 333 AF_Script_InitMetricsFunc script_metrics_init; 334 AF_Script_ScaleMetricsFunc script_metrics_scale; 335 AF_Script_DoneMetricsFunc script_metrics_done; 336 337 AF_Script_InitHintsFunc script_hints_init; 338 AF_Script_ApplyHintsFunc script_hints_apply; 339 340 } AF_ScriptClassRec; 341 342 343 /* */ 344 345 FT_END_HEADER 346 347 #endif /* __AFTYPES_H__ */ 348 349 350 /* END */ 351