1 /* 2 * Copyright © 2018 Google, Inc. 3 * 4 * This is part of HarfBuzz, a text shaping library. 5 * 6 * Permission is hereby granted, without written agreement and without 7 * license or royalty fees, to use, copy, modify, and distribute this 8 * software and its documentation for any purpose, provided that the 9 * above copyright notice and the following two paragraphs appear in 10 * all copies of this software. 11 * 12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 16 * DAMAGE. 17 * 18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 23 * 24 * Google Author(s): Garret Rieger, Roderick Sheeter 25 */ 26 27 #ifndef HB_SUBSET_PLAN_HH 28 #define HB_SUBSET_PLAN_HH 29 30 #include "hb.hh" 31 32 #include "hb-subset.h" 33 #include "hb-subset-input.hh" 34 35 #include "hb-map.hh" 36 #include "hb-set.hh" 37 38 struct hb_subset_plan_t 39 { 40 hb_object_header_t header; 41 42 bool drop_hints : 1; 43 bool desubroutinize : 1; 44 bool retain_gids : 1; 45 46 // For each cp that we'd like to retain maps to the corresponding gid. 47 hb_set_t *unicodes; 48 49 // name_ids we would like to retain 50 hb_set_t *name_ids; 51 52 // Tables which should be dropped. 53 hb_set_t *drop_tables; 54 55 // The glyph subset 56 hb_map_t *codepoint_to_glyph; 57 58 // Old -> New glyph id mapping 59 hb_map_t *glyph_map; 60 hb_map_t *reverse_glyph_map; 61 62 // Plan is only good for a specific source/dest so keep them with it 63 hb_face_t *source; 64 hb_face_t *dest; 65 66 unsigned int _num_output_glyphs; 67 hb_set_t *_glyphset; 68 hb_set_t *_glyphset_gsub; 69 70 public: 71 72 /* 73 * The set of input glyph ids which will be retained in the subset. 74 * Does NOT include ids kept due to retain_gids. You probably want to use 75 * glyph_map/reverse_glyph_map. 76 */ 77 inline const hb_set_t * glyphsethb_subset_plan_t78 glyphset () const 79 { 80 return _glyphset; 81 } 82 83 /* 84 * The set of input glyph ids which will be retained in the subset. 85 */ 86 inline const hb_set_t * glyphset_gsubhb_subset_plan_t87 glyphset_gsub () const 88 { 89 return _glyphset_gsub; 90 } 91 92 /* 93 * The total number of output glyphs in the final subset. 94 */ 95 inline unsigned int num_output_glyphshb_subset_plan_t96 num_output_glyphs () const 97 { 98 return _num_output_glyphs; 99 } 100 101 /* 102 * Given an output gid , returns true if that glyph id is an empty 103 * glyph (ie. it's a gid that we are dropping all data for). 104 */ is_empty_glyphhb_subset_plan_t105 inline bool is_empty_glyph (hb_codepoint_t gid) const 106 { 107 return !_glyphset->has (gid); 108 } 109 new_gid_for_codepointhb_subset_plan_t110 inline bool new_gid_for_codepoint (hb_codepoint_t codepoint, 111 hb_codepoint_t *new_gid) const 112 { 113 hb_codepoint_t old_gid = codepoint_to_glyph->get (codepoint); 114 if (old_gid == HB_MAP_VALUE_INVALID) 115 return false; 116 117 return new_gid_for_old_gid (old_gid, new_gid); 118 } 119 new_gid_for_old_gidhb_subset_plan_t120 inline bool new_gid_for_old_gid (hb_codepoint_t old_gid, 121 hb_codepoint_t *new_gid) const 122 { 123 hb_codepoint_t gid = glyph_map->get (old_gid); 124 if (gid == HB_MAP_VALUE_INVALID) 125 return false; 126 127 *new_gid = gid; 128 return true; 129 } 130 old_gid_for_new_gidhb_subset_plan_t131 inline bool old_gid_for_new_gid (hb_codepoint_t new_gid, 132 hb_codepoint_t *old_gid) const 133 { 134 hb_codepoint_t gid = reverse_glyph_map->get (new_gid); 135 if (gid == HB_MAP_VALUE_INVALID) 136 return false; 137 138 *old_gid = gid; 139 return true; 140 } 141 142 inline bool add_tablehb_subset_plan_t143 add_table (hb_tag_t tag, 144 hb_blob_t *contents) 145 { 146 hb_blob_t *source_blob = source->reference_table (tag); 147 DEBUG_MSG(SUBSET, nullptr, "add table %c%c%c%c, dest %d bytes, source %d bytes", 148 HB_UNTAG(tag), 149 hb_blob_get_length (contents), 150 hb_blob_get_length (source_blob)); 151 hb_blob_destroy (source_blob); 152 return hb_face_builder_add_table (dest, tag, contents); 153 } 154 }; 155 156 typedef struct hb_subset_plan_t hb_subset_plan_t; 157 158 HB_INTERNAL hb_subset_plan_t * 159 hb_subset_plan_create (hb_face_t *face, 160 hb_subset_input_t *input); 161 162 HB_INTERNAL void 163 hb_subset_plan_destroy (hb_subset_plan_t *plan); 164 165 #endif /* HB_SUBSET_PLAN_HH */ 166