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_PRIVATE_HH 30 #define HB_OT_MAP_PRIVATE_HH 31 32 #include "hb-buffer-private.hh" 33 34 35 struct hb_ot_shape_plan_t; 36 37 static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS}; 38 39 struct hb_ot_map_t 40 { 41 friend struct hb_ot_map_builder_t; 42 43 public: 44 45 struct feature_map_t { 46 hb_tag_t tag; /* should be first for our bsearch to work */ 47 unsigned int index[2]; /* GSUB/GPOS */ 48 unsigned int stage[2]; /* GSUB/GPOS */ 49 unsigned int shift; 50 hb_mask_t mask; 51 hb_mask_t _1_mask; /* mask for value=1, for quick access */ 52 unsigned int needs_fallback : 1; 53 unsigned int auto_zwj : 1; 54 cmphb_ot_map_t::feature_map_t55 static int cmp (const feature_map_t *a, const feature_map_t *b) 56 { return a->tag < b->tag ? -1 : a->tag > b->tag ? 1 : 0; } 57 }; 58 59 struct lookup_map_t { 60 unsigned short index; 61 unsigned short auto_zwj : 1; 62 hb_mask_t mask; 63 cmphb_ot_map_t::lookup_map_t64 static int cmp (const lookup_map_t *a, const lookup_map_t *b) 65 { return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; } 66 }; 67 68 typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); 69 70 struct stage_map_t { 71 unsigned int last_lookup; /* Cumulative */ 72 pause_func_t pause_func; 73 }; 74 75 hb_ot_map_thb_ot_map_t76 hb_ot_map_t (void) { memset (this, 0, sizeof (*this)); } 77 get_global_maskhb_ot_map_t78 inline hb_mask_t get_global_mask (void) const { return global_mask; } 79 get_maskhb_ot_map_t80 inline hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = NULL) const { 81 const feature_map_t *map = features.bsearch (&feature_tag); 82 if (shift) *shift = map ? map->shift : 0; 83 return map ? map->mask : 0; 84 } 85 needs_fallbackhb_ot_map_t86 inline bool needs_fallback (hb_tag_t feature_tag) const { 87 const feature_map_t *map = features.bsearch (&feature_tag); 88 return map ? map->needs_fallback : false; 89 } 90 get_1_maskhb_ot_map_t91 inline hb_mask_t get_1_mask (hb_tag_t feature_tag) const { 92 const feature_map_t *map = features.bsearch (&feature_tag); 93 return map ? map->_1_mask : 0; 94 } 95 get_feature_indexhb_ot_map_t96 inline unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const { 97 const feature_map_t *map = features.bsearch (&feature_tag); 98 return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX; 99 } 100 get_feature_stagehb_ot_map_t101 inline unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const { 102 const feature_map_t *map = features.bsearch (&feature_tag); 103 return map ? map->stage[table_index] : (unsigned int) -1; 104 } 105 get_stage_lookupshb_ot_map_t106 inline void get_stage_lookups (unsigned int table_index, unsigned int stage, 107 const struct lookup_map_t **plookups, unsigned int *lookup_count) const { 108 if (unlikely (stage == (unsigned int) -1)) { 109 *plookups = NULL; 110 *lookup_count = 0; 111 return; 112 } 113 assert (stage <= stages[table_index].len); 114 unsigned int start = stage ? stages[table_index][stage - 1].last_lookup : 0; 115 unsigned int end = stage < stages[table_index].len ? stages[table_index][stage].last_lookup : lookups[table_index].len; 116 *plookups = &lookups[table_index][start]; 117 *lookup_count = end - start; 118 } 119 120 HB_INTERNAL void collect_lookups (unsigned int table_index, hb_set_t *lookups) const; 121 template <typename Proxy> 122 HB_INTERNAL inline void apply (const Proxy &proxy, 123 const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 124 HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 125 HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 126 finishhb_ot_map_t127 inline void finish (void) { 128 features.finish (); 129 for (unsigned int table_index = 0; table_index < 2; table_index++) 130 { 131 lookups[table_index].finish (); 132 stages[table_index].finish (); 133 } 134 } 135 136 public: 137 hb_tag_t chosen_script[2]; 138 bool found_script[2]; 139 140 private: 141 142 HB_INTERNAL void add_lookups (hb_face_t *face, 143 unsigned int table_index, 144 unsigned int feature_index, 145 hb_mask_t mask, 146 bool auto_zwj); 147 148 hb_mask_t global_mask; 149 150 hb_prealloced_array_t<feature_map_t, 8> features; 151 hb_prealloced_array_t<lookup_map_t, 32> lookups[2]; /* GSUB/GPOS */ 152 hb_prealloced_array_t<stage_map_t, 4> stages[2]; /* GSUB/GPOS */ 153 }; 154 155 enum hb_ot_map_feature_flags_t { 156 F_NONE = 0x0000u, 157 F_GLOBAL = 0x0001u, /* Feature applies to all characters; results in no mask allocated for it. */ 158 F_HAS_FALLBACK = 0x0002u, /* Has fallback implementation, so include mask bit even if feature not found. */ 159 F_MANUAL_ZWJ = 0x0004u, /* Don't skip over ZWJ when matching. */ 160 F_GLOBAL_SEARCH = 0x0008u /* If feature not found in LangSys, look for it in global feature list and pick one. */ 161 }; 162 HB_MARK_AS_FLAG_T (hb_ot_map_feature_flags_t); 163 /* Macro version for where const is desired. */ 164 #define F_COMBINE(l,r) (hb_ot_map_feature_flags_t ((unsigned int) (l) | (unsigned int) (r))) 165 166 167 struct hb_ot_map_builder_t 168 { 169 public: 170 171 HB_INTERNAL hb_ot_map_builder_t (hb_face_t *face_, 172 const hb_segment_properties_t *props_); 173 174 HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value, 175 hb_ot_map_feature_flags_t flags); 176 add_global_bool_featurehb_ot_map_builder_t177 inline void add_global_bool_feature (hb_tag_t tag) 178 { add_feature (tag, 1, F_GLOBAL); } 179 add_gsub_pausehb_ot_map_builder_t180 inline void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func) 181 { add_pause (0, pause_func); } add_gpos_pausehb_ot_map_builder_t182 inline void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func) 183 { add_pause (1, pause_func); } 184 185 HB_INTERNAL void compile (struct hb_ot_map_t &m); 186 finishhb_ot_map_builder_t187 inline void finish (void) { 188 feature_infos.finish (); 189 for (unsigned int table_index = 0; table_index < 2; table_index++) 190 { 191 stages[table_index].finish (); 192 } 193 } 194 195 private: 196 197 struct feature_info_t { 198 hb_tag_t tag; 199 unsigned int seq; /* sequence#, used for stable sorting only */ 200 unsigned int max_value; 201 hb_ot_map_feature_flags_t flags; 202 unsigned int default_value; /* for non-global features, what should the unset glyphs take */ 203 unsigned int stage[2]; /* GSUB/GPOS */ 204 cmphb_ot_map_builder_t::feature_info_t205 static int cmp (const feature_info_t *a, const feature_info_t *b) 206 { return (a->tag != b->tag) ? (a->tag < b->tag ? -1 : 1) : 207 (a->seq < b->seq ? -1 : a->seq > b->seq ? 1 : 0); } 208 }; 209 210 struct stage_info_t { 211 unsigned int index; 212 hb_ot_map_t::pause_func_t pause_func; 213 }; 214 215 HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func); 216 217 public: 218 219 hb_face_t *face; 220 hb_segment_properties_t props; 221 222 hb_tag_t chosen_script[2]; 223 bool found_script[2]; 224 unsigned int script_index[2], language_index[2]; 225 226 private: 227 228 unsigned int current_stage[2]; /* GSUB/GPOS */ 229 hb_prealloced_array_t<feature_info_t, 32> feature_infos; 230 hb_prealloced_array_t<stage_info_t, 8> stages[2]; /* GSUB/GPOS */ 231 }; 232 233 234 235 #endif /* HB_OT_MAP_PRIVATE_HH */ 236