hb-ot-map-private.hh revision 36925f695d349a53d52ecc3a58f18240a6977463 
1/*
2 * Copyright (C) 2009,2010  Red Hat, Inc.
3 * Copyright (C) 2010  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-ot-shape-private.hh"
33
34#include "hb-ot-layout.h"
35
36HB_BEGIN_DECLS
37
38
39#define MAX_FEATURES 100 /* FIXME */
40#define MAX_LOOKUPS 1000 /* FIXME */
41
42static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS};
43
44struct hb_ot_map_t {
45
46  private:
47
48  struct feature_info_t {
49    hb_tag_t tag;
50    unsigned int value;
51    unsigned int seq;
52    bool global;
53
54    static int cmp (const feature_info_t *a, const feature_info_t *b)
55    { return (a->tag != b->tag) ?  (a->tag < b->tag ? -1 : 1) : (a->seq < b->seq ? -1 : 1); }
56  };
57
58  struct feature_map_t {
59    hb_tag_t tag; /* should be first for our bsearch to work */
60    unsigned int index[2]; /* GSUB, GPOS */
61    unsigned int shift;
62    hb_mask_t mask;
63
64    static int cmp (const feature_map_t *a, const feature_map_t *b)
65    { return a->tag < b->tag ? -1 : a->tag > b->tag ? 1 : 0; }
66  };
67
68  struct lookup_map_t {
69    unsigned int index;
70    hb_mask_t mask;
71
72    static int cmp (const lookup_map_t *a, const lookup_map_t *b)
73    { return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; }
74  };
75
76
77  void
78  add_lookups (hb_ot_shape_context_t *c,
79	       unsigned int  table_index,
80	       unsigned int  feature_index,
81	       hb_mask_t     mask)
82  {
83    unsigned int i = MAX_LOOKUPS - lookup_count[table_index];
84    lookup_map_t *lookups = lookup_maps[table_index] + lookup_count[table_index];
85
86    unsigned int *lookup_indices = (unsigned int *) lookups;
87
88    hb_ot_layout_feature_get_lookup_indexes (c->face,
89					     table_tags[table_index],
90					     feature_index,
91					     0, &i,
92					     lookup_indices);
93
94    lookup_count[table_index] += i;
95
96    while (i--) {
97      lookups[i].mask = mask;
98      lookups[i].index = lookup_indices[i];
99    }
100  }
101
102
103
104  public:
105
106  hb_ot_map_t (void) : feature_count (0) {}
107
108  void add_feature (hb_tag_t tag,
109		    unsigned int value,
110		    bool global)
111  {
112    feature_info_t *info = &feature_infos[feature_count++];
113    info->tag = tag;
114    info->value = value;
115    info->seq = feature_count;
116    info->global = global;
117  }
118
119  HB_INTERNAL void compile (hb_ot_shape_context_t *c);
120
121  hb_mask_t get_global_mask (void) const { return global_mask; }
122
123  hb_mask_t get_mask (hb_tag_t tag, unsigned int *shift) const {
124    const feature_map_t *map = (const feature_map_t *) bsearch (&tag, feature_maps, feature_count, sizeof (feature_maps[0]), (hb_compare_func_t) feature_map_t::cmp);
125    if (shift) *shift = map ? map->shift : 0;
126    return map ? map->mask : 0;
127  }
128
129  inline void substitute (hb_ot_shape_context_t *c) const {
130    for (unsigned int i = 0; i < lookup_count[0]; i++)
131      hb_ot_layout_substitute_lookup (c->face, c->buffer, lookup_maps[0][i].index, lookup_maps[0][i].mask);
132  }
133
134  inline void position (hb_ot_shape_context_t *c) const {
135    for (unsigned int i = 0; i < lookup_count[1]; i++)
136      hb_ot_layout_position_lookup (c->font, c->face, c->buffer, lookup_maps[1][i].index, lookup_maps[1][i].mask);
137  }
138
139  private:
140
141  hb_mask_t global_mask;
142
143  unsigned int feature_count;
144  feature_info_t feature_infos[MAX_FEATURES]; /* used before compile() only */
145  feature_map_t feature_maps[MAX_FEATURES];
146
147  lookup_map_t lookup_maps[2][MAX_LOOKUPS]; /* GSUB/GPOS */
148  unsigned int lookup_count[2];
149};
150
151
152
153HB_END_DECLS
154
155#endif /* HB_OT_MAP_PRIVATE_HH */
156