1 /* 2 * Copyright 2009,2010 Red Hat, Inc. 3 * Copyright 2010,2011,2012,2013 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 #ifndef HB_OT_MAP_HH 30 #define HB_OT_MAP_HH 31 32 #include "hb-buffer.hh" 33 34 35 #define HB_OT_MAP_MAX_BITS 8u 36 #define HB_OT_MAP_MAX_VALUE ((1u << HB_OT_MAP_MAX_BITS) - 1u) 37 38 struct hb_ot_shape_plan_t; 39 40 static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS}; 41 42 struct hb_ot_map_t 43 { 44 friend struct hb_ot_map_builder_t; 45 46 public: 47 48 struct feature_map_t { 49 hb_tag_t tag; /* should be first for our bsearch to work */ 50 unsigned int index[2]; /* GSUB/GPOS */ 51 unsigned int stage[2]; /* GSUB/GPOS */ 52 unsigned int shift; 53 hb_mask_t mask; 54 hb_mask_t _1_mask; /* mask for value=1, for quick access */ 55 unsigned int needs_fallback : 1; 56 unsigned int auto_zwnj : 1; 57 unsigned int auto_zwj : 1; 58 unsigned int random : 1; 59 60 int cmp (const hb_tag_t tag_) const 61 { return tag_ < tag ? -1 : tag_ > tag ? 1 : 0; } 62 }; 63 64 struct lookup_map_t { 65 unsigned short index; 66 unsigned short auto_zwnj : 1; 67 unsigned short auto_zwj : 1; 68 unsigned short random : 1; 69 hb_mask_t mask; 70 71 static int cmp (const void *pa, const void *pb) 72 { 73 const lookup_map_t *a = (const lookup_map_t *) pa; 74 const lookup_map_t *b = (const lookup_map_t *) pb; 75 return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; 76 } 77 }; 78 79 typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); 80 81 struct stage_map_t { 82 unsigned int last_lookup; /* Cumulative */ 83 pause_func_t pause_func; 84 }; 85 86 void init () 87 { 88 memset (this, 0, sizeof (*this)); 89 90 features.init (); 91 for (unsigned int table_index = 0; table_index < 2; table_index++) 92 { 93 lookups[table_index].init (); 94 stages[table_index].init (); 95 } 96 } 97 void fini () 98 { 99 features.fini (); 100 for (unsigned int table_index = 0; table_index < 2; table_index++) 101 { 102 lookups[table_index].fini (); 103 stages[table_index].fini (); 104 } 105 } 106 107 hb_mask_t get_global_mask () const { return global_mask; } 108 109 hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = nullptr) const 110 { 111 const feature_map_t *map = features.bsearch (feature_tag); 112 if (shift) *shift = map ? map->shift : 0; 113 return map ? map->mask : 0; 114 } 115 116 bool needs_fallback (hb_tag_t feature_tag) const 117 { 118 const feature_map_t *map = features.bsearch (feature_tag); 119 return map ? map->needs_fallback : false; 120 } 121 122 hb_mask_t get_1_mask (hb_tag_t feature_tag) const 123 { 124 const feature_map_t *map = features.bsearch (feature_tag); 125 return map ? map->_1_mask : 0; 126 } 127 128 unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const 129 { 130 const feature_map_t *map = features.bsearch (feature_tag); 131 return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX; 132 } 133 134 unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const 135 { 136 const feature_map_t *map = features.bsearch (feature_tag); 137 return map ? map->stage[table_index] : (unsigned int) -1; 138 } 139 140 void get_stage_lookups (unsigned int table_index, unsigned int stage, 141 const struct lookup_map_t **plookups, unsigned int *lookup_count) const 142 { 143 if (unlikely (stage == (unsigned int) -1)) { 144 *plookups = nullptr; 145 *lookup_count = 0; 146 return; 147 } 148 assert (stage <= stages[table_index].len); 149 unsigned int start = stage ? stages[table_index][stage - 1].last_lookup : 0; 150 unsigned int end = stage < stages[table_index].len ? stages[table_index][stage].last_lookup : lookups[table_index].len; 151 *plookups = end == start ? nullptr : &lookups[table_index][start]; 152 *lookup_count = end - start; 153 } 154 155 HB_INTERNAL void collect_lookups (unsigned int table_index, hb_set_t *lookups) const; 156 template <typename Proxy> 157 HB_INTERNAL inline void apply (const Proxy &proxy, 158 const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 159 HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 160 HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 161 162 public: 163 hb_tag_t chosen_script[2]; 164 bool found_script[2]; 165 166 private: 167 168 hb_mask_t global_mask; 169 170 hb_vector_t<feature_map_t, 8> features; 171 hb_vector_t<lookup_map_t, 16> lookups[2]; /* GSUB/GPOS */ 172 hb_vector_t<stage_map_t, 4> stages[2]; /* GSUB/GPOS */ 173 }; 174 175 enum hb_ot_map_feature_flags_t 176 { 177 F_NONE = 0x0000u, 178 F_GLOBAL = 0x0001u, /* Feature applies to all characters; results in no mask allocated for it. */ 179 F_HAS_FALLBACK = 0x0002u, /* Has fallback implementation, so include mask bit even if feature not found. */ 180 F_MANUAL_ZWNJ = 0x0004u, /* Don't skip over ZWNJ when matching **context**. */ 181 F_MANUAL_ZWJ = 0x0008u, /* Don't skip over ZWJ when matching **input**. */ 182 F_MANUAL_JOINERS = F_MANUAL_ZWNJ | F_MANUAL_ZWJ, 183 F_GLOBAL_MANUAL_JOINERS= F_GLOBAL | F_MANUAL_JOINERS, 184 F_GLOBAL_HAS_FALLBACK = F_GLOBAL | F_HAS_FALLBACK, 185 F_GLOBAL_SEARCH = 0x0010u, /* If feature not found in LangSys, look for it in global feature list and pick one. */ 186 F_RANDOM = 0x0020u /* Randomly select a glyph from an AlternateSubstFormat1 subtable. */ 187 }; 188 HB_MARK_AS_FLAG_T (hb_ot_map_feature_flags_t); 189 190 191 struct hb_ot_map_feature_t 192 { 193 hb_tag_t tag; 194 hb_ot_map_feature_flags_t flags; 195 }; 196 197 struct hb_ot_shape_plan_key_t; 198 199 struct hb_ot_map_builder_t 200 { 201 public: 202 203 HB_INTERNAL hb_ot_map_builder_t (hb_face_t *face_, 204 const hb_segment_properties_t *props_); 205 206 HB_INTERNAL ~hb_ot_map_builder_t (); 207 208 HB_INTERNAL void add_feature (hb_tag_t tag, 209 hb_ot_map_feature_flags_t flags=F_NONE, 210 unsigned int value=1); 211 212 void add_feature (const hb_ot_map_feature_t &feat) 213 { add_feature (feat.tag, feat.flags); } 214 215 void enable_feature (hb_tag_t tag, 216 hb_ot_map_feature_flags_t flags=F_NONE, 217 unsigned int value=1) 218 { add_feature (tag, F_GLOBAL | flags, value); } 219 220 void disable_feature (hb_tag_t tag) 221 { add_feature (tag, F_GLOBAL, 0); } 222 223 void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func) 224 { add_pause (0, pause_func); } 225 void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func) 226 { add_pause (1, pause_func); } 227 228 HB_INTERNAL void compile (hb_ot_map_t &m, 229 const hb_ot_shape_plan_key_t &key); 230 231 private: 232 233 HB_INTERNAL void add_lookups (hb_ot_map_t &m, 234 unsigned int table_index, 235 unsigned int feature_index, 236 unsigned int variations_index, 237 hb_mask_t mask, 238 bool auto_zwnj = true, 239 bool auto_zwj = true, 240 bool random = false); 241 242 struct feature_info_t { 243 hb_tag_t tag; 244 unsigned int seq; /* sequence#, used for stable sorting only */ 245 unsigned int max_value; 246 hb_ot_map_feature_flags_t flags; 247 unsigned int default_value; /* for non-global features, what should the unset glyphs take */ 248 unsigned int stage[2]; /* GSUB/GPOS */ 249 250 static int cmp (const void *pa, const void *pb) 251 { 252 const feature_info_t *a = (const feature_info_t *) pa; 253 const feature_info_t *b = (const feature_info_t *) pb; 254 return (a->tag != b->tag) ? (a->tag < b->tag ? -1 : 1) : 255 (a->seq < b->seq ? -1 : a->seq > b->seq ? 1 : 0); 256 } 257 }; 258 259 struct stage_info_t { 260 unsigned int index; 261 hb_ot_map_t::pause_func_t pause_func; 262 }; 263 264 HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func); 265 266 public: 267 268 hb_face_t *face; 269 hb_segment_properties_t props; 270 271 hb_tag_t chosen_script[2]; 272 bool found_script[2]; 273 unsigned int script_index[2], language_index[2]; 274 275 private: 276 277 unsigned int current_stage[2]; /* GSUB/GPOS */ 278 hb_vector_t<feature_info_t, 32> feature_infos; 279 hb_vector_t<stage_info_t, 8> stages[2]; /* GSUB/GPOS */ 280 }; 281 282 283 284 #endif /* HB_OT_MAP_HH */ 285
