1 /* 2 * Copyright 2009,2010 Red Hat, Inc. 3 * Copyright 2010,2011,2013 Google, Inc. 4 * 5 * This is part of HarfBuzz, a text shaping library. 6 * 7 * Permission is hereby granted, without written agreement and without 8 * license or royalty fees, to use, copy, modify, and distribute this 9 * software and its documentation for any purpose, provided that the 10 * above copyright notice and the following two paragraphs appear in 11 * all copies of this software. 12 * 13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 17 * DAMAGE. 18 * 19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 24 * 25 * Red Hat Author(s): Behdad Esfahbod 26 * Google Author(s): Behdad Esfahbod 27 */ 28 29 #include "hb-ot-map-private.hh" 30 31 #include "hb-ot-layout-private.hh" 32 33 34 void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const 35 { 36 for (unsigned int i = 0; i < lookups[table_index].len; i++) 37 hb_set_add (lookups_out, lookups[table_index][i].index); 38 } 39 40 41 hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_, 42 const hb_segment_properties_t *props_) 43 { 44 memset (this, 0, sizeof (*this)); 45 46 face = face_; 47 props = *props_; 48 49 50 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip 51 * features not available in either table and not waste precious bits for them. */ 52 53 hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE}; 54 hb_tag_t language_tag; 55 56 hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]); 57 language_tag = hb_ot_tag_from_language (props.language); 58 59 for (unsigned int table_index = 0; table_index < 2; table_index++) { 60 hb_tag_t table_tag = table_tags[table_index]; 61 found_script[table_index] = (bool) hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]); 62 hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]); 63 } 64 } 65 66 void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, 67 hb_ot_map_feature_flags_t flags) 68 { 69 feature_info_t *info = feature_infos.push(); 70 if (unlikely (!info)) return; 71 if (unlikely (!tag)) return; 72 info->tag = tag; 73 info->seq = feature_infos.len; 74 info->max_value = value; 75 info->flags = flags; 76 info->default_value = (flags & F_GLOBAL) ? value : 0; 77 info->stage[0] = current_stage[0]; 78 info->stage[1] = current_stage[1]; 79 } 80 81 void 82 hb_ot_map_builder_t::add_lookups (hb_ot_map_t &m, 83 hb_face_t *face, 84 unsigned int table_index, 85 unsigned int feature_index, 86 unsigned int variations_index, 87 hb_mask_t mask, 88 bool auto_zwj) 89 { 90 unsigned int lookup_indices[32]; 91 unsigned int offset, len; 92 unsigned int table_lookup_count; 93 94 table_lookup_count = hb_ot_layout_table_get_lookup_count (face, table_tags[table_index]); 95 96 offset = 0; 97 do { 98 len = ARRAY_LENGTH (lookup_indices); 99 hb_ot_layout_feature_with_variations_get_lookups (face, 100 table_tags[table_index], 101 feature_index, 102 variations_index, 103 offset, &len, 104 lookup_indices); 105 106 for (unsigned int i = 0; i < len; i++) 107 { 108 if (lookup_indices[i] >= table_lookup_count) 109 continue; 110 hb_ot_map_t::lookup_map_t *lookup = m.lookups[table_index].push (); 111 if (unlikely (!lookup)) 112 return; 113 lookup->mask = mask; 114 lookup->index = lookup_indices[i]; 115 lookup->auto_zwj = auto_zwj; 116 } 117 118 offset += len; 119 } while (len == ARRAY_LENGTH (lookup_indices)); 120 } 121 122 123 void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func) 124 { 125 stage_info_t *s = stages[table_index].push (); 126 if (likely (s)) { 127 s->index = current_stage[table_index]; 128 s->pause_func = pause_func; 129 } 130 131 current_stage[table_index]++; 132 } 133 134 void 135 hb_ot_map_builder_t::compile (hb_ot_map_t &m, 136 const int *coords, 137 unsigned int num_coords) 138 { 139 m.global_mask = 1; 140 141 unsigned int required_feature_index[2]; 142 hb_tag_t required_feature_tag[2]; 143 /* We default to applying required feature in stage 0. If the required 144 * feature has a tag that is known to the shaper, we apply required feature 145 * in the stage for that tag. 146 */ 147 unsigned int required_feature_stage[2] = {0, 0}; 148 149 for (unsigned int table_index = 0; table_index < 2; table_index++) 150 { 151 m.chosen_script[table_index] = chosen_script[table_index]; 152 m.found_script[table_index] = found_script[table_index]; 153 154 hb_ot_layout_language_get_required_feature (face, 155 table_tags[table_index], 156 script_index[table_index], 157 language_index[table_index], 158 &required_feature_index[table_index], 159 &required_feature_tag[table_index]); 160 } 161 162 if (!feature_infos.len) 163 return; 164 165 /* Sort features and merge duplicates */ 166 { 167 feature_infos.qsort (); 168 unsigned int j = 0; 169 for (unsigned int i = 1; i < feature_infos.len; i++) 170 if (feature_infos[i].tag != feature_infos[j].tag) 171 feature_infos[++j] = feature_infos[i]; 172 else { 173 if (feature_infos[i].flags & F_GLOBAL) { 174 feature_infos[j].flags |= F_GLOBAL; 175 feature_infos[j].max_value = feature_infos[i].max_value; 176 feature_infos[j].default_value = feature_infos[i].default_value; 177 } else { 178 feature_infos[j].flags &= ~F_GLOBAL; 179 feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value); 180 /* Inherit default_value from j */ 181 } 182 feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK); 183 feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]); 184 feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]); 185 } 186 feature_infos.shrink (j + 1); 187 } 188 189 190 /* Allocate bits now */ 191 unsigned int next_bit = 1; 192 for (unsigned int i = 0; i < feature_infos.len; i++) 193 { 194 const feature_info_t *info = &feature_infos[i]; 195 196 unsigned int bits_needed; 197 198 if ((info->flags & F_GLOBAL) && info->max_value == 1) 199 /* Uses the global bit */ 200 bits_needed = 0; 201 else 202 /* Limit to 8 bits per feature. */ 203 bits_needed = MIN(8u, _hb_bit_storage (info->max_value)); 204 205 if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t)) 206 continue; /* Feature disabled, or not enough bits. */ 207 208 209 hb_bool_t found = false; 210 unsigned int feature_index[2]; 211 for (unsigned int table_index = 0; table_index < 2; table_index++) 212 { 213 if (required_feature_tag[table_index] == info->tag) 214 required_feature_stage[table_index] = info->stage[table_index]; 215 216 found |= hb_ot_layout_language_find_feature (face, 217 table_tags[table_index], 218 script_index[table_index], 219 language_index[table_index], 220 info->tag, 221 &feature_index[table_index]); 222 } 223 if (!found && (info->flags & F_GLOBAL_SEARCH)) 224 { 225 for (unsigned int table_index = 0; table_index < 2; table_index++) 226 { 227 found |= hb_ot_layout_table_find_feature (face, 228 table_tags[table_index], 229 info->tag, 230 &feature_index[table_index]); 231 } 232 } 233 if (!found && !(info->flags & F_HAS_FALLBACK)) 234 continue; 235 236 237 hb_ot_map_t::feature_map_t *map = m.features.push (); 238 if (unlikely (!map)) 239 break; 240 241 map->tag = info->tag; 242 map->index[0] = feature_index[0]; 243 map->index[1] = feature_index[1]; 244 map->stage[0] = info->stage[0]; 245 map->stage[1] = info->stage[1]; 246 map->auto_zwj = !(info->flags & F_MANUAL_ZWJ); 247 if ((info->flags & F_GLOBAL) && info->max_value == 1) { 248 /* Uses the global bit */ 249 map->shift = 0; 250 map->mask = 1; 251 } else { 252 map->shift = next_bit; 253 map->mask = (1u << (next_bit + bits_needed)) - (1u << next_bit); 254 next_bit += bits_needed; 255 m.global_mask |= (info->default_value << map->shift) & map->mask; 256 } 257 map->_1_mask = (1u << map->shift) & map->mask; 258 map->needs_fallback = !found; 259 260 } 261 feature_infos.shrink (0); /* Done with these */ 262 263 264 add_gsub_pause (NULL); 265 add_gpos_pause (NULL); 266 267 for (unsigned int table_index = 0; table_index < 2; table_index++) 268 { 269 /* Collect lookup indices for features */ 270 271 unsigned int variations_index; 272 hb_ot_layout_table_find_feature_variations (face, 273 table_tags[table_index], 274 coords, 275 num_coords, 276 &variations_index); 277 278 unsigned int stage_index = 0; 279 unsigned int last_num_lookups = 0; 280 for (unsigned stage = 0; stage < current_stage[table_index]; stage++) 281 { 282 if (required_feature_index[table_index] != HB_OT_LAYOUT_NO_FEATURE_INDEX && 283 required_feature_stage[table_index] == stage) 284 add_lookups (m, face, table_index, 285 required_feature_index[table_index], 286 variations_index, 287 1 /* mask */, 288 true /* auto_zwj */); 289 290 for (unsigned i = 0; i < m.features.len; i++) 291 if (m.features[i].stage[table_index] == stage) 292 add_lookups (m, face, table_index, 293 m.features[i].index[table_index], 294 variations_index, 295 m.features[i].mask, 296 m.features[i].auto_zwj); 297 298 /* Sort lookups and merge duplicates */ 299 if (last_num_lookups < m.lookups[table_index].len) 300 { 301 m.lookups[table_index].qsort (last_num_lookups, m.lookups[table_index].len); 302 303 unsigned int j = last_num_lookups; 304 for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++) 305 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index) 306 m.lookups[table_index][++j] = m.lookups[table_index][i]; 307 else 308 { 309 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask; 310 m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj; 311 } 312 m.lookups[table_index].shrink (j + 1); 313 } 314 315 last_num_lookups = m.lookups[table_index].len; 316 317 if (stage_index < stages[table_index].len && stages[table_index][stage_index].index == stage) { 318 hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push (); 319 if (likely (stage_map)) { 320 stage_map->last_lookup = last_num_lookups; 321 stage_map->pause_func = stages[table_index][stage_index].pause_func; 322 } 323 324 stage_index++; 325 } 326 } 327 } 328 } 329
