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
38struct 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 *
78 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 *
87 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
96 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 */
105 inline bool is_empty_glyph (hb_codepoint_t gid) const
106 {
107 return !_glyphset->has (gid);
108 }
109
110 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
120 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
131 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
143 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
156typedef struct hb_subset_plan_t hb_subset_plan_t;
157
158HB_INTERNAL hb_subset_plan_t *
159hb_subset_plan_create (hb_face_t *face,
160 hb_subset_input_t *input);
161
162HB_INTERNAL void
163hb_subset_plan_destroy (hb_subset_plan_t *plan);
164
165#endif /* HB_SUBSET_PLAN_HH */
166