hb-ot-map-private.hh revision 851784f8372004e0a40b698c0cdc2d7db8629aa2
1/* 2 * Copyright © 2009,2010 Red Hat, Inc. 3 * Copyright © 2010,2011,2012 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#include "hb-ot-layout-private.hh" 35 36 37static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS}; 38 39struct 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 hb_bool_t needs_fallback; 53 54 static int cmp (const feature_map_t *a, const feature_map_t *b) 55 { return a->tag < b->tag ? -1 : a->tag > b->tag ? 1 : 0; } 56 }; 57 58 struct lookup_map_t { 59 unsigned int index; 60 hb_mask_t mask; 61 62 static int cmp (const lookup_map_t *a, const lookup_map_t *b) 63 { return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; } 64 }; 65 66 typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer); 67 68 struct pause_map_t { 69 unsigned int num_lookups; /* Cumulative */ 70 pause_func_t callback; 71 }; 72 73 74 hb_ot_map_t (void) { memset (this, 0, sizeof (*this)); } 75 76 inline hb_mask_t get_global_mask (void) const { return global_mask; } 77 78 inline hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = NULL) const { 79 const feature_map_t *map = features.bsearch (&feature_tag); 80 if (shift) *shift = map ? map->shift : 0; 81 return map ? map->mask : 0; 82 } 83 84 inline bool needs_fallback (hb_tag_t feature_tag) const { 85 const feature_map_t *map = features.bsearch (&feature_tag); 86 return map ? map->needs_fallback : false; 87 } 88 89 inline hb_mask_t get_1_mask (hb_tag_t feature_tag) const { 90 const feature_map_t *map = features.bsearch (&feature_tag); 91 return map ? map->_1_mask : 0; 92 } 93 94 inline unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const { 95 const feature_map_t *map = features.bsearch (&feature_tag); 96 return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX; 97 } 98 99 inline unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const { 100 const feature_map_t *map = features.bsearch (&feature_tag); 101 return map ? map->stage[table_index] : (unsigned int) -1; 102 } 103 104 inline void get_stage_lookups (unsigned int table_index, unsigned int stage, 105 const struct lookup_map_t **plookups, unsigned int *lookup_count) const { 106 if (unlikely (stage == (unsigned int) -1)) { 107 *plookups = NULL; 108 *lookup_count = 0; 109 return; 110 } 111 assert (stage <= pauses[table_index].len); 112 unsigned int start = stage ? pauses[table_index][stage - 1].num_lookups : 0; 113 unsigned int end = stage < pauses[table_index].len ? pauses[table_index][stage].num_lookups : lookups[table_index].len; 114 *plookups = &lookups[table_index][start]; 115 *lookup_count = end - start; 116 } 117 118 HB_INTERNAL void substitute_closure (const struct hb_ot_shape_plan_t *plan, hb_face_t *face, hb_set_t *glyphs) const; 119 HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 120 HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const; 121 122 inline void finish (void) { 123 features.finish (); 124 lookups[0].finish (); 125 lookups[1].finish (); 126 pauses[0].finish (); 127 pauses[1].finish (); 128 } 129 130 public: 131 hb_tag_t chosen_script[2]; 132 bool found_script[2]; 133 134 private: 135 136 HB_INTERNAL void add_lookups (hb_face_t *face, 137 unsigned int table_index, 138 unsigned int feature_index, 139 hb_mask_t mask); 140 141 hb_mask_t global_mask; 142 143 hb_prealloced_array_t<feature_map_t, 8> features; 144 hb_prealloced_array_t<lookup_map_t, 32> lookups[2]; /* GSUB/GPOS */ 145 hb_prealloced_array_t<pause_map_t, 1> pauses[2]; /* GSUB/GPOS */ 146}; 147 148 149struct hb_ot_map_builder_t 150{ 151 public: 152 153 HB_INTERNAL hb_ot_map_builder_t (hb_face_t *face_, 154 const hb_segment_properties_t *props_); 155 156 HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value, bool global, bool has_fallback = false); 157 158 inline void add_bool_feature (hb_tag_t tag, bool global = true, bool has_fallback = false) 159 { add_feature (tag, 1, global, has_fallback); } 160 161 inline void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func) 162 { add_pause (0, pause_func); } 163 inline void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func) 164 { add_pause (1, pause_func); } 165 166 HB_INTERNAL void compile (struct hb_ot_map_t &m); 167 168 inline void finish (void) { 169 feature_infos.finish (); 170 pauses[0].finish (); 171 pauses[1].finish (); 172 } 173 174 private: 175 176 struct feature_info_t { 177 hb_tag_t tag; 178 unsigned int seq; /* sequence#, used for stable sorting only */ 179 unsigned int max_value; 180 bool global; /* whether the feature applies value to every glyph in the buffer */ 181 bool has_fallback; /* whether to allocate bits even if feature not found */ 182 unsigned int default_value; /* for non-global features, what should the unset glyphs take */ 183 unsigned int stage[2]; /* GSUB/GPOS */ 184 185 static int cmp (const feature_info_t *a, const feature_info_t *b) 186 { return (a->tag != b->tag) ? (a->tag < b->tag ? -1 : 1) : (a->seq < b->seq ? -1 : 1); } 187 }; 188 189 struct pause_info_t { 190 unsigned int stage; 191 hb_ot_map_t::pause_func_t callback; 192 }; 193 194 HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func); 195 196 public: 197 198 hb_face_t *face; 199 hb_segment_properties_t props; 200 201 hb_tag_t chosen_script[2]; 202 bool found_script[2]; 203 unsigned int script_index[2], language_index[2]; 204 205 private: 206 207 unsigned int current_stage[2]; /* GSUB/GPOS */ 208 hb_prealloced_array_t<feature_info_t,16> feature_infos; 209 hb_prealloced_array_t<pause_info_t, 1> pauses[2]; /* GSUB/GPOS */ 210}; 211 212 213 214#endif /* HB_OT_MAP_PRIVATE_HH */ 215