summaryrefslogtreecommitdiffstats
path: root/src/3rdparty/harfbuzz-ng/src/hb-ot-var-mvar-table.hh
blob: 6d6977761897c688bdeb5ca9248302b8804e7b2f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
 * Copyright © 2017  Google, Inc.
 *
 *  This is part of HarfBuzz, a text shaping library.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and its documentation for any purpose, provided that the
 * above copyright notice and the following two paragraphs appear in
 * all copies of this software.
 *
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Google Author(s): Behdad Esfahbod
 */

#ifndef HB_OT_VAR_MVAR_TABLE_HH
#define HB_OT_VAR_MVAR_TABLE_HH

#include "hb-ot-var-common.hh"


namespace OT {


struct VariationValueRecord
{
  bool sanitize (hb_sanitize_context_t *c) const
  {
    TRACE_SANITIZE (this);
    return_trace (c->check_struct (this));
  }

  bool subset (hb_subset_context_t *c,
               const hb_map_t& varidx_map) const
  {
    TRACE_SUBSET (this);
    auto *out = c->serializer->embed (*this);
    if (unlikely (!out)) return_trace (false);

    hb_codepoint_t *new_idx;
    return_trace (c->serializer->check_assign (out->varIdx,
                                               (varidx_map.has (varIdx, &new_idx)) ? *new_idx : HB_OT_LAYOUT_NO_VARIATIONS_INDEX,
                                               HB_SERIALIZE_ERROR_INT_OVERFLOW));
  }

  public:
  Tag		valueTag;	/* Four-byte tag identifying a font-wide measure. */
  VarIdx	varIdx;		/* Outer/inner index into VariationStore item. */

  public:
  DEFINE_SIZE_STATIC (8);
};


/*
 * MVAR -- Metrics Variations
 * https://docs.microsoft.com/en-us/typography/opentype/spec/mvar
 */
#define HB_OT_TAG_MVAR HB_TAG('M','V','A','R')

struct MVAR
{
  static constexpr hb_tag_t tableTag = HB_OT_TAG_MVAR;

  bool sanitize (hb_sanitize_context_t *c) const
  {
    TRACE_SANITIZE (this);
    return_trace (version.sanitize (c) &&
		  hb_barrier () &&
		  likely (version.major == 1) &&
		  c->check_struct (this) &&
		  hb_barrier () &&
		  valueRecordSize >= VariationValueRecord::static_size &&
		  varStore.sanitize (c, this) &&
		  c->check_range (valuesZ.arrayZ,
				  valueRecordCount,
				  valueRecordSize));
  }

  bool subset (hb_subset_context_t *c) const
  {
    TRACE_SUBSET (this);
#ifdef HB_NO_VAR
    return_trace (false);
#endif

    if (c->plan->all_axes_pinned)
      return_trace (false);

    MVAR *out = c->serializer->start_embed (*this);
    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
    out->version = version;
    out->reserved = reserved;
    out->valueRecordSize = valueRecordSize;
    out->valueRecordCount = valueRecordCount;

    item_variations_t item_vars;
    const VariationStore& src_var_store = this+varStore;

    if (!item_vars.instantiate (src_var_store, c->plan))
      return_trace (false);

    /* serialize varstore */
    if (!out->varStore.serialize_serialize (c->serializer, item_vars.has_long_word (),
                                            c->plan->axis_tags,
                                            item_vars.get_region_list (),
                                            item_vars.get_vardata_encodings ()))
      return_trace (false);

    /* serialize value records array */
    unsigned value_rec_count = valueRecordCount;
    const VariationValueRecord *record = reinterpret_cast<const VariationValueRecord*> (valuesZ.arrayZ);
    for (unsigned i = 0; i < value_rec_count; i++)
    {
      if (!record->subset (c, item_vars.get_varidx_map ())) return_trace (false);
      record++;
    }
    return_trace (true);
  }

  float get_var (hb_tag_t tag,
		 const int *coords, unsigned int coord_count) const
  {
    const VariationValueRecord *record;
    record = (VariationValueRecord *) hb_bsearch (tag,
						  (const VariationValueRecord *)
						    (const HBUINT8 *) valuesZ,
						  valueRecordCount, valueRecordSize,
						  tag_compare);
    if (!record)
      return 0.;

    return (this+varStore).get_delta (record->varIdx, coords, coord_count);
  }

protected:
  static int tag_compare (const void *pa, const void *pb)
  {
    const hb_tag_t *a = (const hb_tag_t *) pa;
    const Tag *b = (const Tag *) pb;
    return b->cmp (*a);
  }

  protected:
  FixedVersion<>version;	/* Version of the metrics variation table
				 * initially set to 0x00010000u */
  HBUINT16	reserved;	/* Not used; set to 0. */
  HBUINT16	valueRecordSize;/* The size in bytes of each value record —
				 * must be greater than zero. */
  HBUINT16	valueRecordCount;/* The number of value records — may be zero. */
  Offset16To<VariationStore>
		varStore;	/* Offset to item variation store table. */
  UnsizedArrayOf<HBUINT8>
		valuesZ;	/* Array of value records. The records must be
				 * in binary order of their valueTag field. */

  public:
  DEFINE_SIZE_ARRAY (12, valuesZ);
};

} /* namespace OT */


#define HB_ADD_MVAR_VAR(tag, field) \
       c->serializer->check_assign (table->field, \
				    roundf (table->field + \
					    MVAR.get_var (tag, \
							  c->plan->normalized_coords.arrayZ, \
							  c->plan->normalized_coords.length)), \
				    HB_SERIALIZE_ERROR_INT_OVERFLOW)


#endif /* HB_OT_VAR_MVAR_TABLE_HH */