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 35 hb_ot_map_t::add_lookups (hb_face_t *face, 36 unsigned int table_index, 37 unsigned int feature_index, 38 hb_mask_t mask, 39 bool auto_zwj) 40 { 41 unsigned int lookup_indices[32]; 42 unsigned int offset, len; 43 44 offset = 0; 45 do { 46 len = ARRAY_LENGTH (lookup_indices); 47 hb_ot_layout_feature_get_lookups (face, 48 table_tags[table_index], 49 feature_index, 50 offset, &len, 51 lookup_indices); 52 53 for (unsigned int i = 0; i < len; i++) { 54 hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push (); 55 if (unlikely (!lookup)) 56 return; 57 lookup->mask = mask; 58 lookup->index = lookup_indices[i]; 59 lookup->auto_zwj = auto_zwj; 60 } 61 62 offset += len; 63 } while (len == ARRAY_LENGTH (lookup_indices)); 64 } 65 66 hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_, 67 const hb_segment_properties_t *props_) 68 { 69 memset (this, 0, sizeof (*this)); 70 71 face = face_; 72 props = *props_; 73 74 75 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip 76 * features not available in either table and not waste precious bits for them. */ 77 78 hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE}; 79 hb_tag_t language_tag; 80 81 hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]); 82 language_tag = hb_ot_tag_from_language (props.language); 83 84 for (unsigned int table_index = 0; table_index < 2; table_index++) { 85 hb_tag_t table_tag = table_tags[table_index]; 86 found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]); 87 hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]); 88 } 89 } 90 91 void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, 92 hb_ot_map_feature_flags_t flags) 93 { 94 feature_info_t *info = feature_infos.push(); 95 if (unlikely (!info)) return; 96 info->tag = tag; 97 info->seq = feature_infos.len; 98 info->max_value = value; 99 info->flags = flags; 100 info->default_value = (flags & F_GLOBAL) ? value : 0; 101 info->stage[0] = current_stage[0]; 102 info->stage[1] = current_stage[1]; 103 } 104 105 inline void hb_ot_map_t::apply (unsigned int table_index, 106 const hb_ot_shape_plan_t *plan, 107 hb_font_t *font, 108 hb_buffer_t *buffer) const 109 { 110 unsigned int i = 0; 111 112 for (unsigned int stage_index = 0; stage_index < stages[table_index].len; stage_index++) { 113 const stage_map_t *stage = &stages[table_index][stage_index]; 114 for (; i < stage->last_lookup; i++) 115 switch (table_index) 116 { 117 case 0: 118 hb_ot_layout_substitute_lookup (font, buffer, lookups[table_index][i].index, 119 lookups[table_index][i].mask, 120 lookups[table_index][i].auto_zwj); 121 break; 122 123 case 1: 124 hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, 125 lookups[table_index][i].mask, 126 lookups[table_index][i].auto_zwj); 127 break; 128 } 129 130 if (stage->pause_func) 131 { 132 buffer->clear_output (); 133 stage->pause_func (plan, font, buffer); 134 } 135 } 136 } 137 138 void hb_ot_map_t::substitute (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const 139 { 140 apply (0, plan, font, buffer); 141 } 142 143 void hb_ot_map_t::position (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const 144 { 145 apply (1, plan, font, buffer); 146 } 147 148 149 void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const 150 { 151 for (unsigned int i = 0; i < lookups[table_index].len; i++) 152 hb_set_add (lookups_out, lookups[table_index][i].index); 153 } 154 155 void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func) 156 { 157 stage_info_t *s = stages[table_index].push (); 158 if (likely (s)) { 159 s->index = current_stage[table_index]; 160 s->pause_func = pause_func; 161 } 162 163 current_stage[table_index]++; 164 } 165 166 void 167 hb_ot_map_builder_t::compile (hb_ot_map_t &m) 168 { 169 m.global_mask = 1; 170 171 for (unsigned int table_index = 0; table_index < 2; table_index++) { 172 m.chosen_script[table_index] = chosen_script[table_index]; 173 m.found_script[table_index] = found_script[table_index]; 174 } 175 176 if (!feature_infos.len) 177 return; 178 179 /* Sort features and merge duplicates */ 180 { 181 feature_infos.sort (); 182 unsigned int j = 0; 183 for (unsigned int i = 1; i < feature_infos.len; i++) 184 if (feature_infos[i].tag != feature_infos[j].tag) 185 feature_infos[++j] = feature_infos[i]; 186 else { 187 if (feature_infos[i].flags & F_GLOBAL) { 188 feature_infos[j].flags |= F_GLOBAL; 189 feature_infos[j].max_value = feature_infos[i].max_value; 190 feature_infos[j].default_value = feature_infos[i].default_value; 191 } else { 192 feature_infos[j].flags &= ~F_GLOBAL; 193 feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value); 194 /* Inherit default_value from j */ 195 } 196 feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK); 197 feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]); 198 feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]); 199 } 200 feature_infos.shrink (j + 1); 201 } 202 203 204 /* Allocate bits now */ 205 unsigned int next_bit = 1; 206 for (unsigned int i = 0; i < feature_infos.len; i++) { 207 const feature_info_t *info = &feature_infos[i]; 208 209 unsigned int bits_needed; 210 211 if ((info->flags & F_GLOBAL) && info->max_value == 1) 212 /* Uses the global bit */ 213 bits_needed = 0; 214 else 215 bits_needed = _hb_bit_storage (info->max_value); 216 217 if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t)) 218 continue; /* Feature disabled, or not enough bits. */ 219 220 221 bool found = false; 222 unsigned int feature_index[2]; 223 for (unsigned int table_index = 0; table_index < 2; table_index++) 224 found |= hb_ot_layout_language_find_feature (face, 225 table_tags[table_index], 226 script_index[table_index], 227 language_index[table_index], 228 info->tag, 229 &feature_index[table_index]); 230 if (!found && !(info->flags & F_HAS_FALLBACK)) 231 continue; 232 233 234 hb_ot_map_t::feature_map_t *map = m.features.push (); 235 if (unlikely (!map)) 236 break; 237 238 map->tag = info->tag; 239 map->index[0] = feature_index[0]; 240 map->index[1] = feature_index[1]; 241 map->stage[0] = info->stage[0]; 242 map->stage[1] = info->stage[1]; 243 map->auto_zwj = !(info->flags & F_MANUAL_ZWJ); 244 if ((info->flags & F_GLOBAL) && info->max_value == 1) { 245 /* Uses the global bit */ 246 map->shift = 0; 247 map->mask = 1; 248 } else { 249 map->shift = next_bit; 250 map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit); 251 next_bit += bits_needed; 252 m.global_mask |= (info->default_value << map->shift) & map->mask; 253 } 254 map->_1_mask = (1 << map->shift) & map->mask; 255 map->needs_fallback = !found; 256 257 } 258 feature_infos.shrink (0); /* Done with these */ 259 260 261 add_gsub_pause (NULL); 262 add_gpos_pause (NULL); 263 264 for (unsigned int table_index = 0; table_index < 2; table_index++) { 265 hb_tag_t table_tag = table_tags[table_index]; 266 267 /* Collect lookup indices for features */ 268 269 unsigned int required_feature_index; 270 if (hb_ot_layout_language_get_required_feature_index (face, 271 table_tag, 272 script_index[table_index], 273 language_index[table_index], 274 &required_feature_index)) 275 m.add_lookups (face, table_index, required_feature_index, 1, true); 276 277 unsigned int stage_index = 0; 278 unsigned int last_num_lookups = 0; 279 for (unsigned stage = 0; stage < current_stage[table_index]; stage++) 280 { 281 for (unsigned i = 0; i < m.features.len; i++) 282 if (m.features[i].stage[table_index] == stage) 283 m.add_lookups (face, table_index, 284 m.features[i].index[table_index], 285 m.features[i].mask, 286 m.features[i].auto_zwj); 287 288 /* Sort lookups and merge duplicates */ 289 if (last_num_lookups < m.lookups[table_index].len) 290 { 291 m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len); 292 293 unsigned int j = last_num_lookups; 294 for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++) 295 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index) 296 m.lookups[table_index][++j] = m.lookups[table_index][i]; 297 else 298 { 299 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask; 300 m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj; 301 } 302 m.lookups[table_index].shrink (j + 1); 303 } 304 305 last_num_lookups = m.lookups[table_index].len; 306 307 if (stage_index < stages[table_index].len && stages[table_index][stage_index].index == stage) { 308 hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push (); 309 if (likely (stage_map)) { 310 stage_map->last_lookup = last_num_lookups; 311 stage_map->pause_func = stages[table_index][stage_index].pause_func; 312 } 313 314 stage_index++; 315 } 316 } 317 } 318 } 319
