1/* 2 * Copyright © 2009,2010 Red Hat, Inc. 3 * Copyright © 2010,2011 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 32void 33hb_ot_map_t::add_lookups (hb_face_t *face, 34 unsigned int table_index, 35 unsigned int feature_index, 36 hb_mask_t mask, 37 bool auto_zwj) 38{ 39 unsigned int lookup_indices[32]; 40 unsigned int offset, len; 41 42 offset = 0; 43 do { 44 len = ARRAY_LENGTH (lookup_indices); 45 hb_ot_layout_feature_get_lookups (face, 46 table_tags[table_index], 47 feature_index, 48 offset, &len, 49 lookup_indices); 50 51 for (unsigned int i = 0; i < len; i++) { 52 hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push (); 53 if (unlikely (!lookup)) 54 return; 55 lookup->mask = mask; 56 lookup->index = lookup_indices[i]; 57 lookup->auto_zwj = auto_zwj; 58 } 59 60 offset += len; 61 } while (len == ARRAY_LENGTH (lookup_indices)); 62} 63 64hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_, 65 const hb_segment_properties_t *props_) 66{ 67 memset (this, 0, sizeof (*this)); 68 69 face = face_; 70 props = *props_; 71 72 73 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip 74 * features not available in either table and not waste precious bits for them. */ 75 76 hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE}; 77 hb_tag_t language_tag; 78 79 hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]); 80 language_tag = hb_ot_tag_from_language (props.language); 81 82 for (unsigned int table_index = 0; table_index < 2; table_index++) { 83 hb_tag_t table_tag = table_tags[table_index]; 84 found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]); 85 hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]); 86 } 87} 88 89void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, 90 hb_ot_map_feature_flags_t flags) 91{ 92 feature_info_t *info = feature_infos.push(); 93 if (unlikely (!info)) return; 94 info->tag = tag; 95 info->seq = feature_infos.len; 96 info->max_value = value; 97 info->flags = flags; 98 info->default_value = (flags & F_GLOBAL) ? value : 0; 99 info->stage[0] = current_stage[0]; 100 info->stage[1] = current_stage[1]; 101} 102 103/* Keep the next two functions in sync. */ 104 105void hb_ot_map_t::substitute (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const 106{ 107 const unsigned int table_index = 0; 108 unsigned int i = 0; 109 110 for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) { 111 const pause_map_t *pause = &pauses[table_index][pause_index]; 112 for (; i < pause->num_lookups; i++) 113 hb_ot_layout_substitute_lookup (font, buffer, 114 lookups[table_index][i].index, 115 lookups[table_index][i].mask, 116 lookups[table_index][i].auto_zwj); 117 118 buffer->clear_output (); 119 120 if (pause->callback) 121 pause->callback (plan, font, buffer); 122 } 123 124 for (; i < lookups[table_index].len; i++) 125 hb_ot_layout_substitute_lookup (font, buffer, lookups[table_index][i].index, 126 lookups[table_index][i].mask, 127 lookups[table_index][i].auto_zwj); 128} 129 130void hb_ot_map_t::position (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const 131{ 132 const unsigned int table_index = 1; 133 unsigned int i = 0; 134 135 for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) { 136 const pause_map_t *pause = &pauses[table_index][pause_index]; 137 for (; i < pause->num_lookups; i++) 138 hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, 139 lookups[table_index][i].mask, 140 lookups[table_index][i].auto_zwj); 141 142 if (pause->callback) 143 pause->callback (plan, font, buffer); 144 } 145 146 for (; i < lookups[table_index].len; i++) 147 hb_ot_layout_position_lookup (font, buffer, lookups[table_index][i].index, 148 lookups[table_index][i].mask, 149 lookups[table_index][i].auto_zwj); 150} 151 152void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const 153{ 154 for (unsigned int i = 0; i < lookups[table_index].len; i++) 155 hb_set_add (lookups_out, lookups[table_index][i].index); 156} 157 158void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func) 159{ 160 pause_info_t *p = pauses[table_index].push (); 161 if (likely (p)) { 162 p->stage = current_stage[table_index]; 163 p->callback = pause_func; 164 } 165 166 current_stage[table_index]++; 167} 168 169void 170hb_ot_map_builder_t::compile (hb_ot_map_t &m) 171{ 172 m.global_mask = 1; 173 174 for (unsigned int table_index = 0; table_index < 2; table_index++) { 175 m.chosen_script[table_index] = chosen_script[table_index]; 176 m.found_script[table_index] = found_script[table_index]; 177 } 178 179 if (!feature_infos.len) 180 return; 181 182 /* Sort features and merge duplicates */ 183 { 184 feature_infos.sort (); 185 unsigned int j = 0; 186 for (unsigned int i = 1; i < feature_infos.len; i++) 187 if (feature_infos[i].tag != feature_infos[j].tag) 188 feature_infos[++j] = feature_infos[i]; 189 else { 190 if (feature_infos[i].flags & F_GLOBAL) { 191 feature_infos[j].flags |= F_GLOBAL; 192 feature_infos[j].max_value = feature_infos[i].max_value; 193 feature_infos[j].default_value = feature_infos[i].default_value; 194 } else { 195 feature_infos[j].flags &= ~F_GLOBAL; 196 feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value); 197 /* Inherit default_value from j */ 198 } 199 feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK); 200 feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]); 201 feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]); 202 } 203 feature_infos.shrink (j + 1); 204 } 205 206 207 /* Allocate bits now */ 208 unsigned int next_bit = 1; 209 for (unsigned int i = 0; i < feature_infos.len; i++) { 210 const feature_info_t *info = &feature_infos[i]; 211 212 unsigned int bits_needed; 213 214 if ((info->flags & F_GLOBAL) && info->max_value == 1) 215 /* Uses the global bit */ 216 bits_needed = 0; 217 else 218 bits_needed = _hb_bit_storage (info->max_value); 219 220 if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t)) 221 continue; /* Feature disabled, or not enough bits. */ 222 223 224 bool found = false; 225 unsigned int feature_index[2]; 226 for (unsigned int table_index = 0; table_index < 2; table_index++) 227 found |= hb_ot_layout_language_find_feature (face, 228 table_tags[table_index], 229 script_index[table_index], 230 language_index[table_index], 231 info->tag, 232 &feature_index[table_index]); 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 = (1 << (next_bit + bits_needed)) - (1 << next_bit); 254 next_bit += bits_needed; 255 m.global_mask |= (info->default_value << map->shift) & map->mask; 256 } 257 map->_1_mask = (1 << 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 hb_tag_t table_tag = table_tags[table_index]; 269 270 /* Collect lookup indices for features */ 271 272 unsigned int required_feature_index; 273 if (hb_ot_layout_language_get_required_feature_index (face, 274 table_tag, 275 script_index[table_index], 276 language_index[table_index], 277 &required_feature_index)) 278 m.add_lookups (face, table_index, required_feature_index, 1, true); 279 280 unsigned int pause_index = 0; 281 unsigned int last_num_lookups = 0; 282 for (unsigned stage = 0; stage < current_stage[table_index]; stage++) 283 { 284 for (unsigned i = 0; i < m.features.len; i++) 285 if (m.features[i].stage[table_index] == stage) 286 m.add_lookups (face, table_index, 287 m.features[i].index[table_index], 288 m.features[i].mask, 289 m.features[i].auto_zwj); 290 291 /* Sort lookups and merge duplicates */ 292 if (last_num_lookups < m.lookups[table_index].len) 293 { 294 m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len); 295 296 unsigned int j = last_num_lookups; 297 for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++) 298 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index) 299 m.lookups[table_index][++j] = m.lookups[table_index][i]; 300 else 301 { 302 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask; 303 m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj; 304 } 305 m.lookups[table_index].shrink (j + 1); 306 } 307 308 last_num_lookups = m.lookups[table_index].len; 309 310 if (pause_index < pauses[table_index].len && pauses[table_index][pause_index].stage == stage) { 311 hb_ot_map_t::pause_map_t *pause_map = m.pauses[table_index].push (); 312 if (likely (pause_map)) { 313 pause_map->num_lookups = last_num_lookups; 314 pause_map->callback = pauses[table_index][pause_index].callback; 315 } 316 317 pause_index++; 318 } 319 } 320 } 321} 322