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, 45 HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF 46 }; 47 48 49 /* Master OT shaper list */ 50 #define HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS \ 51 HB_COMPLEX_SHAPER_IMPLEMENT (default) /* should be first */ \ 52 HB_COMPLEX_SHAPER_IMPLEMENT (arabic) \ 53 HB_COMPLEX_SHAPER_IMPLEMENT (indic) \ 54 HB_COMPLEX_SHAPER_IMPLEMENT (myanmar) \ 55 HB_COMPLEX_SHAPER_IMPLEMENT (sea) \ 56 HB_COMPLEX_SHAPER_IMPLEMENT (thai) \ 57 /* ^--- Add new shapers here */ 58 59 60 struct hb_ot_complex_shaper_t 61 { 62 char name[8]; 63 64 /* collect_features() 65 * Called during shape_plan(). 66 * Shapers should use plan->map to add their features and callbacks. 67 * May be NULL. 68 */ 69 void (*collect_features) (hb_ot_shape_planner_t *plan); 70 71 /* override_features() 72 * Called during shape_plan(). 73 * Shapers should use plan->map to override features and add callbacks after 74 * common features are added. 75 * May be NULL. 76 */ 77 void (*override_features) (hb_ot_shape_planner_t *plan); 78 79 80 /* data_create() 81 * Called at the end of shape_plan(). 82 * Whatever shapers return will be accessible through plan->data later. 83 * If NULL is returned, means a plan failure. 84 */ 85 void *(*data_create) (const hb_ot_shape_plan_t *plan); 86 87 /* data_destroy() 88 * Called when the shape_plan is being destroyed. 89 * plan->data is passed here for destruction. 90 * If NULL is returned, means a plan failure. 91 * May be NULL. 92 */ 93 void (*data_destroy) (void *data); 94 95 96 /* preprocess_text() 97 * Called during shape(). 98 * Shapers can use to modify text before shaping starts. 99 * May be NULL. 100 */ 101 void (*preprocess_text) (const hb_ot_shape_plan_t *plan, 102 hb_buffer_t *buffer, 103 hb_font_t *font); 104 105 106 /* normalization_preference() 107 * Called during shape(). 108 * May be NULL. 109 */ 110 hb_ot_shape_normalization_mode_t 111 (*normalization_preference) (const hb_segment_properties_t *props); 112 113 /* decompose() 114 * Called during shape()'s normalization. 115 * May be NULL. 116 */ 117 bool (*decompose) (const hb_ot_shape_normalize_context_t *c, 118 hb_codepoint_t ab, 119 hb_codepoint_t *a, 120 hb_codepoint_t *b); 121 122 /* compose() 123 * Called during shape()'s normalization. 124 * May be NULL. 125 */ 126 bool (*compose) (const hb_ot_shape_normalize_context_t *c, 127 hb_codepoint_t a, 128 hb_codepoint_t b, 129 hb_codepoint_t *ab); 130 131 /* setup_masks() 132 * Called during shape(). 133 * Shapers should use map to get feature masks and set on buffer. 134 * Shapers may NOT modify characters. 135 * May be NULL. 136 */ 137 void (*setup_masks) (const hb_ot_shape_plan_t *plan, 138 hb_buffer_t *buffer, 139 hb_font_t *font); 140 141 hb_ot_shape_zero_width_marks_type_t zero_width_marks; 142 143 bool fallback_position; 144 }; 145 146 #define HB_COMPLEX_SHAPER_IMPLEMENT(name) extern HB_INTERNAL const hb_ot_complex_shaper_t _hb_ot_complex_shaper_##name; 147 HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS 148 #undef HB_COMPLEX_SHAPER_IMPLEMENT 149 150 151 static inline const hb_ot_complex_shaper_t * 152 hb_ot_shape_complex_categorize (const hb_ot_shape_planner_t *planner) 153 { 154 switch ((hb_tag_t) planner->props.script) 155 { 156 default: 157 return &_hb_ot_complex_shaper_default; 158 159 160 /* Unicode-1.1 additions */ 161 case HB_SCRIPT_ARABIC: 162 case HB_SCRIPT_MONGOLIAN: 163 case HB_SCRIPT_SYRIAC: 164 165 /* Unicode-5.0 additions */ 166 case HB_SCRIPT_NKO: 167 case HB_SCRIPT_PHAGS_PA: 168 169 /* Unicode-6.0 additions */ 170 case HB_SCRIPT_MANDAIC: 171 172 /* For Arabic script, use the Arabic shaper even if no OT script tag was found. 173 * This is because we do fallback shaping for Arabic script (and not others). */ 174 if (planner->map.chosen_script[0] != HB_OT_TAG_DEFAULT_SCRIPT || 175 planner->props.script == HB_SCRIPT_ARABIC) 176 return &_hb_ot_complex_shaper_arabic; 177 else 178 return &_hb_ot_complex_shaper_default; 179 180 181 /* Unicode-1.1 additions */ 182 case HB_SCRIPT_THAI: 183 case HB_SCRIPT_LAO: 184 185 return &_hb_ot_complex_shaper_thai; 186 187 188 189 /* ^--- Add new shapers here */ 190 191 192 #if 0 193 /* Note: 194 * 195 * These disabled scripts are listed in ucd/IndicSyllabicCategory.txt, but according 196 * to Martin Hosken and Jonathan Kew do not require complex shaping. 197 * 198 * TODO We should automate figuring out which scripts do not need complex shaping 199 * 200 * TODO We currently keep data for these scripts in our indic table. Need to fix the 201 * generator to not do that. 202 */ 203 204 205 /* Simple? */ 206 207 /* Unicode-3.2 additions */ 208 case HB_SCRIPT_BUHID: 209 case HB_SCRIPT_HANUNOO: 210 211 /* Unicode-5.1 additions */ 212 case HB_SCRIPT_SAURASHTRA: 213 214 /* Unicode-6.0 additions */ 215 case HB_SCRIPT_BATAK: 216 case HB_SCRIPT_BRAHMI: 217 218 219 /* Simple */ 220 221 /* Unicode-1.1 additions */ 222 /* These have their own shaper now. */ 223 case HB_SCRIPT_LAO: 224 case HB_SCRIPT_THAI: 225 226 /* Unicode-2.0 additions */ 227 case HB_SCRIPT_TIBETAN: 228 229 /* Unicode-3.2 additions */ 230 case HB_SCRIPT_TAGALOG: 231 case HB_SCRIPT_TAGBANWA: 232 233 /* Unicode-4.0 additions */ 234 case HB_SCRIPT_LIMBU: 235 case HB_SCRIPT_TAI_LE: 236 237 /* Unicode-4.1 additions */ 238 case HB_SCRIPT_KHAROSHTHI: 239 case HB_SCRIPT_SYLOTI_NAGRI: 240 241 /* Unicode-5.1 additions */ 242 case HB_SCRIPT_KAYAH_LI: 243 244 /* Unicode-5.2 additions */ 245 case HB_SCRIPT_TAI_VIET: 246 247 248 #endif 249 250 /* Unicode-1.1 additions */ 251 case HB_SCRIPT_BENGALI: 252 case HB_SCRIPT_DEVANAGARI: 253 case HB_SCRIPT_GUJARATI: 254 case HB_SCRIPT_GURMUKHI: 255 case HB_SCRIPT_KANNADA: 256 case HB_SCRIPT_MALAYALAM: 257 case HB_SCRIPT_ORIYA: 258 case HB_SCRIPT_TAMIL: 259 case HB_SCRIPT_TELUGU: 260 261 /* Unicode-3.0 additions */ 262 case HB_SCRIPT_SINHALA: 263 264 /* Unicode-4.1 additions */ 265 case HB_SCRIPT_BUGINESE: 266 267 /* Unicode-5.0 additions */ 268 case HB_SCRIPT_BALINESE: 269 270 /* Unicode-5.1 additions */ 271 case HB_SCRIPT_LEPCHA: 272 case HB_SCRIPT_REJANG: 273 case HB_SCRIPT_SUNDANESE: 274 275 /* Unicode-5.2 additions */ 276 case HB_SCRIPT_JAVANESE: 277 case HB_SCRIPT_KAITHI: 278 case HB_SCRIPT_MEETEI_MAYEK: 279 280 /* Unicode-6.0 additions */ 281 282 /* Unicode-6.1 additions */ 283 case HB_SCRIPT_CHAKMA: 284 case HB_SCRIPT_SHARADA: 285 case HB_SCRIPT_TAKRI: 286 287 /* If the designer designed the font for the 'DFLT' script, 288 * use the default shaper. Otherwise, use the Indic shaper. 289 * Note that for some simple scripts, there may not be *any* 290 * GSUB/GPOS needed, so there may be no scripts found! */ 291 if (planner->map.chosen_script[0] == HB_TAG ('D','F','L','T')) 292 return &_hb_ot_complex_shaper_default; 293 else 294 return &_hb_ot_complex_shaper_indic; 295 296 case HB_SCRIPT_KHMER: 297 /* A number of Khmer fonts in the wild don't have a 'pref' feature, 298 * and as such won't shape properly via the Indic shaper; 299 * however, they typically have 'liga' / 'clig' features that implement 300 * the necessary "reordering" by means of ligature substitutions. 301 * So we send such pref-less fonts through the generic shaper instead. */ 302 if (planner->map.found_script[0] && 303 hb_ot_layout_language_find_feature (planner->face, HB_OT_TAG_GSUB, 304 planner->map.script_index[0], 305 planner->map.language_index[0], 306 HB_TAG ('p','r','e','f'), 307 NULL)) 308 return &_hb_ot_complex_shaper_indic; 309 else 310 return &_hb_ot_complex_shaper_default; 311 312 case HB_SCRIPT_MYANMAR: 313 /* For Myanmar, we only want to use the Myanmar shaper if the "new" script 314 * tag is found. For "old" script tag we want to use the default shaper. */ 315 if (planner->map.chosen_script[0] == HB_TAG ('m','y','m','2')) 316 return &_hb_ot_complex_shaper_myanmar; 317 else 318 return &_hb_ot_complex_shaper_default; 319 320 /* Unicode-4.1 additions */ 321 case HB_SCRIPT_NEW_TAI_LUE: 322 323 /* Unicode-5.1 additions */ 324 case HB_SCRIPT_CHAM: 325 326 /* Unicode-5.2 additions */ 327 case HB_SCRIPT_TAI_THAM: 328 329 /* If the designer designed the font for the 'DFLT' script, 330 * use the default shaper. Otherwise, use the Indic shaper. 331 * Note that for some simple scripts, there may not be *any* 332 * GSUB/GPOS needed, so there may be no scripts found! */ 333 if (planner->map.chosen_script[0] == HB_TAG ('D','F','L','T')) 334 return &_hb_ot_complex_shaper_default; 335 else 336 return &_hb_ot_complex_shaper_sea; 337 } 338 } 339 340 341 #endif /* HB_OT_SHAPE_COMPLEX_PRIVATE_HH */ 342