1 /* 2 * Copyright 2010,2011,2012 Google, Inc. 3 * 4 * This is part of HarfBuzz, a text shaping library. 5 * 6 * Permission is hereby granted, without written agreement and without 7 * license or royalty fees, to use, copy, modify, and distribute this 8 * software and its documentation for any purpose, provided that the 9 * above copyright notice and the following two paragraphs appear in 10 * all copies of this software. 11 * 12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 16 * DAMAGE. 17 * 18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 23 * 24 * Google Author(s): Behdad Esfahbod 25 */ 26 27 #ifndef HB_OT_SHAPE_COMPLEX_PRIVATE_HH 28 #define HB_OT_SHAPE_COMPLEX_PRIVATE_HH 29 30 #include "hb-private.hh" 31 32 #include "hb-ot-shape-private.hh" 33 #include "hb-ot-shape-normalize-private.hh" 34 35 36 37 /* buffer var allocations, used by complex shapers */ 38 #define complex_var_u8_0() var2.u8[2] 39 #define complex_var_u8_1() var2.u8[3] 40 41 42 enum hb_ot_shape_zero_width_marks_type_t { 43 HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE, 44 // HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_EARLY, 45 HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_UNICODE_LATE, 46 HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY, 47 HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE 48 }; 49 50 51 /* Master OT shaper list */ 52 #define HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS \ 53 HB_COMPLEX_SHAPER_IMPLEMENT (default) /* should be first */ \ 54 HB_COMPLEX_SHAPER_IMPLEMENT (arabic) \ 55 HB_COMPLEX_SHAPER_IMPLEMENT (indic) \ 56 HB_COMPLEX_SHAPER_IMPLEMENT (myanmar) \ 57 HB_COMPLEX_SHAPER_IMPLEMENT (sea) \ 58 HB_COMPLEX_SHAPER_IMPLEMENT (thai) \ 59 /* ^--- Add new shapers here */ 60 61 62 struct hb_ot_complex_shaper_t 63 { 64 char name[8]; 65 66 /* collect_features() 67 * Called during shape_plan(). 68 * Shapers should use plan->map to add their features and callbacks. 69 * May be NULL. 70 */ 71 void (*collect_features) (hb_ot_shape_planner_t *plan); 72 73 /* override_features() 74 * Called during shape_plan(). 75 * Shapers should use plan->map to override features and add callbacks after 76 * common features are added. 77 * May be NULL. 78 */ 79 void (*override_features) (hb_ot_shape_planner_t *plan); 80 81 82 /* data_create() 83 * Called at the end of shape_plan(). 84 * Whatever shapers return will be accessible through plan->data later. 85 * If NULL is returned, means a plan failure. 86 */ 87 void *(*data_create) (const hb_ot_shape_plan_t *plan); 88 89 /* data_destroy() 90 * Called when the shape_plan is being destroyed. 91 * plan->data is passed here for destruction. 92 * If NULL is returned, means a plan failure. 93 * May be NULL. 94 */ 95 void (*data_destroy) (void *data); 96 97 98 /* preprocess_text() 99 * Called during shape(). 100 * Shapers can use to modify text before shaping starts. 101 * May be NULL. 102 */ 103 void (*preprocess_text) (const hb_ot_shape_plan_t *plan, 104 hb_buffer_t *buffer, 105 hb_font_t *font); 106 107 108 /* normalization_preference() 109 * Called during shape(). 110 * May be NULL. 111 */ 112 hb_ot_shape_normalization_mode_t 113 (*normalization_preference) (const hb_segment_properties_t *props); 114 115 /* decompose() 116 * Called during shape()'s normalization. 117 * May be NULL. 118 */ 119 bool (*decompose) (const hb_ot_shape_normalize_context_t *c, 120 hb_codepoint_t ab, 121 hb_codepoint_t *a, 122 hb_codepoint_t *b); 123 124 /* compose() 125 * Called during shape()'s normalization. 126 * May be NULL. 127 */ 128 bool (*compose) (const hb_ot_shape_normalize_context_t *c, 129 hb_codepoint_t a, 130 hb_codepoint_t b, 131 hb_codepoint_t *ab); 132 133 /* setup_masks() 134 * Called during shape(). 135 * Shapers should use map to get feature masks and set on buffer. 136 * Shapers may NOT modify characters. 137 * May be NULL. 138 */ 139 void (*setup_masks) (const hb_ot_shape_plan_t *plan, 140 hb_buffer_t *buffer, 141 hb_font_t *font); 142 143 hb_ot_shape_zero_width_marks_type_t zero_width_marks; 144 145 bool fallback_position; 146 }; 147 148 #define HB_COMPLEX_SHAPER_IMPLEMENT(name) extern HB_INTERNAL const hb_ot_complex_shaper_t _hb_ot_complex_shaper_##name; 149 HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS 150 #undef HB_COMPLEX_SHAPER_IMPLEMENT 151 152 153 static inline const hb_ot_complex_shaper_t * 154 hb_ot_shape_complex_categorize (const hb_ot_shape_planner_t *planner) 155 { 156 switch ((hb_tag_t) planner->props.script) 157 { 158 default: 159 return &_hb_ot_complex_shaper_default; 160 161 162 /* Unicode-1.1 additions */ 163 case HB_SCRIPT_ARABIC: 164 165 /* Unicode-3.0 additions */ 166 case HB_SCRIPT_MONGOLIAN: 167 case HB_SCRIPT_SYRIAC: 168 169 /* Unicode-5.0 additions */ 170 case HB_SCRIPT_NKO: 171 case HB_SCRIPT_PHAGS_PA: 172 173 /* Unicode-6.0 additions */ 174 case HB_SCRIPT_MANDAIC: 175 176 /* For Arabic script, use the Arabic shaper even if no OT script tag was found. 177 * This is because we do fallback shaping for Arabic script (and not others). */ 178 if (planner->map.chosen_script[0] != HB_OT_TAG_DEFAULT_SCRIPT || 179 planner->props.script == HB_SCRIPT_ARABIC) 180 return &_hb_ot_complex_shaper_arabic; 181 else 182 return &_hb_ot_complex_shaper_default; 183 184 185 /* Unicode-1.1 additions */ 186 case HB_SCRIPT_THAI: 187 case HB_SCRIPT_LAO: 188 189 return &_hb_ot_complex_shaper_thai; 190 191 192 #if 0 193 /* Note: 194 * Currently we don't have a separate Hangul shaper. The default shaper handles 195 * Hangul by enabling jamo features. We may want to implement a separate shaper 196 * in the future. See this thread for details of what such a shaper would do: 197 * 198 * http://lists.freedesktop.org/archives/harfbuzz/2013-April/003070.html 199 */ 200 /* Unicode-1.1 additions */ 201 case HB_SCRIPT_HANGUL: 202 203 return &_hb_ot_complex_shaper_hangul; 204 #endif 205 206 207 /* ^--- Add new shapers here */ 208 209 210 #if 0 211 /* Note: 212 * 213 * These disabled scripts are listed in ucd/IndicSyllabicCategory.txt, but according 214 * to Martin Hosken and Jonathan Kew do not require complex shaping. 215 * 216 * TODO We should automate figuring out which scripts do not need complex shaping 217 * 218 * TODO We currently keep data for these scripts in our indic table. Need to fix the 219 * generator to not do that. 220 */ 221 222 223 /* Simple? */ 224 225 /* Unicode-3.2 additions */ 226 case HB_SCRIPT_BUHID: 227 case HB_SCRIPT_HANUNOO: 228 229 /* Unicode-5.1 additions */ 230 case HB_SCRIPT_SAURASHTRA: 231 232 /* Unicode-6.0 additions */ 233 case HB_SCRIPT_BATAK: 234 case HB_SCRIPT_BRAHMI: 235 236 237 /* Simple */ 238 239 /* Unicode-1.1 additions */ 240 /* These have their own shaper now. */ 241 case HB_SCRIPT_LAO: 242 case HB_SCRIPT_THAI: 243 244 /* Unicode-2.0 additions */ 245 case HB_SCRIPT_TIBETAN: 246 247 /* Unicode-3.2 additions */ 248 case HB_SCRIPT_TAGALOG: 249 case HB_SCRIPT_TAGBANWA: 250 251 /* Unicode-4.0 additions */ 252 case HB_SCRIPT_LIMBU: 253 case HB_SCRIPT_TAI_LE: 254 255 /* Unicode-4.1 additions */ 256 case HB_SCRIPT_KHAROSHTHI: 257 case HB_SCRIPT_SYLOTI_NAGRI: 258 259 /* Unicode-5.1 additions */ 260 case HB_SCRIPT_KAYAH_LI: 261 262 /* Unicode-5.2 additions */ 263 case HB_SCRIPT_TAI_VIET: 264 265 266 #endif 267 268 /* Unicode-1.1 additions */ 269 case HB_SCRIPT_BENGALI: 270 case HB_SCRIPT_DEVANAGARI: 271 case HB_SCRIPT_GUJARATI: 272 case HB_SCRIPT_GURMUKHI: 273 case HB_SCRIPT_KANNADA: 274 case HB_SCRIPT_MALAYALAM: 275 case HB_SCRIPT_ORIYA: 276 case HB_SCRIPT_TAMIL: 277 case HB_SCRIPT_TELUGU: 278 279 /* Unicode-3.0 additions */ 280 case HB_SCRIPT_SINHALA: 281 282 /* Unicode-5.0 additions */ 283 case HB_SCRIPT_BALINESE: 284 285 /* Unicode-5.1 additions */ 286 case HB_SCRIPT_LEPCHA: 287 case HB_SCRIPT_REJANG: 288 case HB_SCRIPT_SUNDANESE: 289 290 /* Unicode-5.2 additions */ 291 case HB_SCRIPT_JAVANESE: 292 case HB_SCRIPT_KAITHI: 293 case HB_SCRIPT_MEETEI_MAYEK: 294 295 /* Unicode-6.0 additions */ 296 297 /* Unicode-6.1 additions */ 298 case HB_SCRIPT_CHAKMA: 299 case HB_SCRIPT_SHARADA: 300 case HB_SCRIPT_TAKRI: 301 302 /* If the designer designed the font for the 'DFLT' script, 303 * use the default shaper. Otherwise, use the Indic shaper. 304 * Note that for some simple scripts, there may not be *any* 305 * GSUB/GPOS needed, so there may be no scripts found! */ 306 if (planner->map.chosen_script[0] == HB_TAG ('D','F','L','T')) 307 return &_hb_ot_complex_shaper_default; 308 else 309 return &_hb_ot_complex_shaper_indic; 310 311 case HB_SCRIPT_KHMER: 312 /* A number of Khmer fonts in the wild don't have a 'pref' feature, 313 * and as such won't shape properly via the Indic shaper; 314 * however, they typically have 'liga' / 'clig' features that implement 315 * the necessary "reordering" by means of ligature substitutions. 316 * So we send such pref-less fonts through the generic shaper instead. */ 317 if (planner->map.found_script[0] && 318 hb_ot_layout_language_find_feature (planner->face, HB_OT_TAG_GSUB, 319 planner->map.script_index[0], 320 planner->map.language_index[0], 321 HB_TAG ('p','r','e','f'), 322 NULL)) 323 return &_hb_ot_complex_shaper_indic; 324 else 325 return &_hb_ot_complex_shaper_default; 326 327 case HB_SCRIPT_MYANMAR: 328 /* For Myanmar, we only want to use the Myanmar shaper if the "new" script 329 * tag is found. For "old" script tag we want to use the default shaper. */ 330 if (planner->map.chosen_script[0] == HB_TAG ('m','y','m','2')) 331 return &_hb_ot_complex_shaper_myanmar; 332 else 333 return &_hb_ot_complex_shaper_default; 334 335 /* Unicode-4.1 additions */ 336 case HB_SCRIPT_BUGINESE: 337 case HB_SCRIPT_NEW_TAI_LUE: 338 339 /* Unicode-5.1 additions */ 340 case HB_SCRIPT_CHAM: 341 342 /* Unicode-5.2 additions */ 343 case HB_SCRIPT_TAI_THAM: 344 345 /* If the designer designed the font for the 'DFLT' script, 346 * use the default shaper. Otherwise, use the Indic shaper. 347 * Note that for some simple scripts, there may not be *any* 348 * GSUB/GPOS needed, so there may be no scripts found! */ 349 if (planner->map.chosen_script[0] == HB_TAG ('D','F','L','T')) 350 return &_hb_ot_complex_shaper_default; 351 else 352 return &_hb_ot_complex_shaper_sea; 353 } 354 } 355 356 357 #endif /* HB_OT_SHAPE_COMPLEX_PRIVATE_HH */ 358
