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 34void 35hb_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 unsigned int table_lookup_count; 44 45 table_lookup_count = hb_ot_layout_table_get_lookup_count (face, table_tags[table_index]); 46 47 offset = 0; 48 do { 49 len = ARRAY_LENGTH (lookup_indices); 50 hb_ot_layout_feature_get_lookups (face, 51 table_tags[table_index], 52 feature_index, 53 offset, &len, 54 lookup_indices); 55 56 for (unsigned int i = 0; i < len; i++) 57 { 58 if (lookup_indices[i] >= table_lookup_count) 59 continue; 60 hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push (); 61 if (unlikely (!lookup)) 62 return; 63 lookup->mask = mask; 64 lookup->index = lookup_indices[i]; 65 lookup->auto_zwj = auto_zwj; 66 } 67 68 offset += len; 69 } while (len == ARRAY_LENGTH (lookup_indices)); 70} 71 72hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_, 73 const hb_segment_properties_t *props_) 74{ 75 memset (this, 0, sizeof (*this)); 76 77 face = face_; 78 props = *props_; 79 80 81 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip 82 * features not available in either table and not waste precious bits for them. */ 83 84 hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE}; 85 hb_tag_t language_tag; 86 87 hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]); 88 language_tag = hb_ot_tag_from_language (props.language); 89 90 for (unsigned int table_index = 0; table_index < 2; table_index++) { 91 hb_tag_t table_tag = table_tags[table_index]; 92 found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]); 93 hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]); 94 } 95} 96 97void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, 98 hb_ot_map_feature_flags_t flags) 99{ 100 feature_info_t *info = feature_infos.push(); 101 if (unlikely (!info)) return; 102 info->tag = tag; 103 info->seq = feature_infos.len; 104 info->max_value = value; 105 info->flags = flags; 106 info->default_value = (flags & F_GLOBAL) ? value : 0; 107 info->stage[0] = current_stage[0]; 108 info->stage[1] = current_stage[1]; 109} 110 111 112void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const 113{ 114 for (unsigned int i = 0; i < lookups[table_index].len; i++) 115 hb_set_add (lookups_out, lookups[table_index][i].index); 116} 117 118void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func) 119{ 120 stage_info_t *s = stages[table_index].push (); 121 if (likely (s)) { 122 s->index = current_stage[table_index]; 123 s->pause_func = pause_func; 124 } 125 126 current_stage[table_index]++; 127} 128 129void 130hb_ot_map_builder_t::compile (hb_ot_map_t &m) 131{ 132 m.global_mask = 1; 133 134 for (unsigned int table_index = 0; table_index < 2; table_index++) { 135 m.chosen_script[table_index] = chosen_script[table_index]; 136 m.found_script[table_index] = found_script[table_index]; 137 } 138 139 if (!feature_infos.len) 140 return; 141 142 /* Sort features and merge duplicates */ 143 { 144 feature_infos.sort (); 145 unsigned int j = 0; 146 for (unsigned int i = 1; i < feature_infos.len; i++) 147 if (feature_infos[i].tag != feature_infos[j].tag) 148 feature_infos[++j] = feature_infos[i]; 149 else { 150 if (feature_infos[i].flags & F_GLOBAL) { 151 feature_infos[j].flags |= F_GLOBAL; 152 feature_infos[j].max_value = feature_infos[i].max_value; 153 feature_infos[j].default_value = feature_infos[i].default_value; 154 } else { 155 feature_infos[j].flags &= ~F_GLOBAL; 156 feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value); 157 /* Inherit default_value from j */ 158 } 159 feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK); 160 feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]); 161 feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]); 162 } 163 feature_infos.shrink (j + 1); 164 } 165 166 167 /* Allocate bits now */ 168 unsigned int next_bit = 1; 169 for (unsigned int i = 0; i < feature_infos.len; i++) { 170 const feature_info_t *info = &feature_infos[i]; 171 172 unsigned int bits_needed; 173 174 if ((info->flags & F_GLOBAL) && info->max_value == 1) 175 /* Uses the global bit */ 176 bits_needed = 0; 177 else 178 bits_needed = _hb_bit_storage (info->max_value); 179 180 if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t)) 181 continue; /* Feature disabled, or not enough bits. */ 182 183 184 hb_bool_t found = false; 185 unsigned int feature_index[2]; 186 for (unsigned int table_index = 0; table_index < 2; table_index++) 187 found |= hb_ot_layout_language_find_feature (face, 188 table_tags[table_index], 189 script_index[table_index], 190 language_index[table_index], 191 info->tag, 192 &feature_index[table_index]); 193 if (!found && !(info->flags & F_HAS_FALLBACK)) 194 continue; 195 196 197 hb_ot_map_t::feature_map_t *map = m.features.push (); 198 if (unlikely (!map)) 199 break; 200 201 map->tag = info->tag; 202 map->index[0] = feature_index[0]; 203 map->index[1] = feature_index[1]; 204 map->stage[0] = info->stage[0]; 205 map->stage[1] = info->stage[1]; 206 map->auto_zwj = !(info->flags & F_MANUAL_ZWJ); 207 if ((info->flags & F_GLOBAL) && info->max_value == 1) { 208 /* Uses the global bit */ 209 map->shift = 0; 210 map->mask = 1; 211 } else { 212 map->shift = next_bit; 213 map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit); 214 next_bit += bits_needed; 215 m.global_mask |= (info->default_value << map->shift) & map->mask; 216 } 217 map->_1_mask = (1 << map->shift) & map->mask; 218 map->needs_fallback = !found; 219 220 } 221 feature_infos.shrink (0); /* Done with these */ 222 223 224 add_gsub_pause (NULL); 225 add_gpos_pause (NULL); 226 227 for (unsigned int table_index = 0; table_index < 2; table_index++) { 228 hb_tag_t table_tag = table_tags[table_index]; 229 230 /* Collect lookup indices for features */ 231 232 unsigned int required_feature_index; 233 if (hb_ot_layout_language_get_required_feature_index (face, 234 table_tag, 235 script_index[table_index], 236 language_index[table_index], 237 &required_feature_index)) 238 m.add_lookups (face, table_index, required_feature_index, 1, true); 239 240 unsigned int stage_index = 0; 241 unsigned int last_num_lookups = 0; 242 for (unsigned stage = 0; stage < current_stage[table_index]; stage++) 243 { 244 for (unsigned i = 0; i < m.features.len; i++) 245 if (m.features[i].stage[table_index] == stage) 246 m.add_lookups (face, table_index, 247 m.features[i].index[table_index], 248 m.features[i].mask, 249 m.features[i].auto_zwj); 250 251 /* Sort lookups and merge duplicates */ 252 if (last_num_lookups < m.lookups[table_index].len) 253 { 254 m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len); 255 256 unsigned int j = last_num_lookups; 257 for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++) 258 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index) 259 m.lookups[table_index][++j] = m.lookups[table_index][i]; 260 else 261 { 262 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask; 263 m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj; 264 } 265 m.lookups[table_index].shrink (j + 1); 266 } 267 268 last_num_lookups = m.lookups[table_index].len; 269 270 if (stage_index < stages[table_index].len && stages[table_index][stage_index].index == stage) { 271 hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push (); 272 if (likely (stage_map)) { 273 stage_map->last_lookup = last_num_lookups; 274 stage_map->pause_func = stages[table_index][stage_index].pause_func; 275 } 276 277 stage_index++; 278 } 279 } 280 } 281} 282