summaryrefslogtreecommitdiff
path: root/thirdparty/harfbuzz/src/OT/Layout/GSUB/SubstLookup.hh
blob: 8fb3b550976a20d5c615e18de86537d6a407b6e3 (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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
#ifndef OT_LAYOUT_GSUB_SUBSTLOOKUP_HH
#define OT_LAYOUT_GSUB_SUBSTLOOKUP_HH

#include "Common.hh"
#include "SubstLookupSubTable.hh"

namespace OT {
namespace Layout {
namespace GSUB {

struct SubstLookup : Lookup
{
  using SubTable = SubstLookupSubTable;

  bool sanitize (hb_sanitize_context_t *c) const
  { return Lookup::sanitize<SubTable> (c); }

  const SubTable& get_subtable (unsigned int i) const
  { return Lookup::get_subtable<SubTable> (i); }

  static inline bool lookup_type_is_reverse (unsigned int lookup_type)
  { return lookup_type == SubTable::ReverseChainSingle; }

  bool is_reverse () const
  {
    unsigned int type = get_type ();
    if (unlikely (type == SubTable::Extension))
      return reinterpret_cast<const ExtensionSubst &> (get_subtable (0)).is_reverse ();
    return lookup_type_is_reverse (type);
  }

  bool may_have_non_1to1 () const
  {
    hb_have_non_1to1_context_t c;
    return dispatch (&c);
  }

  bool apply (hb_ot_apply_context_t *c) const
  {
    TRACE_APPLY (this);
    return_trace (dispatch (c));
  }

  bool intersects (const hb_set_t *glyphs) const
  {
    hb_intersects_context_t c (glyphs);
    return dispatch (&c);
  }

  hb_closure_context_t::return_t closure (hb_closure_context_t *c, unsigned int this_index) const
  {
    if (!c->should_visit_lookup (this_index))
      return hb_closure_context_t::default_return_value ();

    c->set_recurse_func (dispatch_closure_recurse_func);

    hb_closure_context_t::return_t ret = dispatch (c);

    c->flush ();

    return ret;
  }

  hb_closure_lookups_context_t::return_t closure_lookups (hb_closure_lookups_context_t *c, unsigned this_index) const
  {
    if (c->is_lookup_visited (this_index))
      return hb_closure_lookups_context_t::default_return_value ();

    c->set_lookup_visited (this_index);
    if (!intersects (c->glyphs))
    {
      c->set_lookup_inactive (this_index);
      return hb_closure_lookups_context_t::default_return_value ();
    }

    hb_closure_lookups_context_t::return_t ret = dispatch (c);
    return ret;
  }

  hb_collect_glyphs_context_t::return_t collect_glyphs (hb_collect_glyphs_context_t *c) const
  {
    c->set_recurse_func (dispatch_recurse_func<hb_collect_glyphs_context_t>);
    return dispatch (c);
  }

  template <typename set_t>
  void collect_coverage (set_t *glyphs) const
  {
    hb_collect_coverage_context_t<set_t> c (glyphs);
    dispatch (&c);
  }

  bool would_apply (hb_would_apply_context_t *c,
                    const hb_ot_layout_lookup_accelerator_t *accel) const
  {
    if (unlikely (!c->len)) return false;
    if (!accel->may_have (c->glyphs[0])) return false;
      return dispatch (c);
  }

  bool serialize_single (hb_serialize_context_t *c,
                         uint32_t lookup_props,
                         hb_sorted_array_t<const HBGlyphID16> glyphs,
                         hb_array_t<const HBGlyphID16> substitutes)
  {
    TRACE_SERIALIZE (this);
    if (unlikely (!Lookup::serialize (c, SubTable::Single, lookup_props, 1))) return_trace (false);
    if (c->push<SubTable> ()->u.single.serialize (c, hb_zip (glyphs, substitutes)))
    {
      c->add_link (get_subtables<SubTable> ()[0], c->pop_pack ());
      return_trace (true);
    }
    c->pop_discard ();
    return_trace (false);
  }

  bool serialize_multiple (hb_serialize_context_t *c,
                           uint32_t lookup_props,
                           hb_sorted_array_t<const HBGlyphID16> glyphs,
                           hb_array_t<const unsigned int> substitute_len_list,
                           hb_array_t<const HBGlyphID16> substitute_glyphs_list)
  {
    TRACE_SERIALIZE (this);
    if (unlikely (!Lookup::serialize (c, SubTable::Multiple, lookup_props, 1))) return_trace (false);
    if (c->push<SubTable> ()->u.multiple.
        serialize (c,
                   glyphs,
                   substitute_len_list,
                   substitute_glyphs_list))
    {
      c->add_link (get_subtables<SubTable> ()[0], c->pop_pack ());
      return_trace (true);
    }
    c->pop_discard ();
    return_trace (false);
  }

  bool serialize_alternate (hb_serialize_context_t *c,
                            uint32_t lookup_props,
                            hb_sorted_array_t<const HBGlyphID16> glyphs,
                            hb_array_t<const unsigned int> alternate_len_list,
                            hb_array_t<const HBGlyphID16> alternate_glyphs_list)
  {
    TRACE_SERIALIZE (this);
    if (unlikely (!Lookup::serialize (c, SubTable::Alternate, lookup_props, 1))) return_trace (false);

    if (c->push<SubTable> ()->u.alternate.
        serialize (c,
                   glyphs,
                   alternate_len_list,
                   alternate_glyphs_list))
    {
      c->add_link (get_subtables<SubTable> ()[0], c->pop_pack ());
      return_trace (true);
    }
    c->pop_discard ();
    return_trace (false);
  }

  bool serialize_ligature (hb_serialize_context_t *c,
                           uint32_t lookup_props,
                           hb_sorted_array_t<const HBGlyphID16> first_glyphs,
                           hb_array_t<const unsigned int> ligature_per_first_glyph_count_list,
                           hb_array_t<const HBGlyphID16> ligatures_list,
                           hb_array_t<const unsigned int> component_count_list,
                           hb_array_t<const HBGlyphID16> component_list /* Starting from second for each ligature */)
  {
    TRACE_SERIALIZE (this);
    if (unlikely (!Lookup::serialize (c, SubTable::Ligature, lookup_props, 1))) return_trace (false);
    if (c->push<SubTable> ()->u.ligature.
        serialize (c,
                   first_glyphs,
                   ligature_per_first_glyph_count_list,
                   ligatures_list,
                   component_count_list,
                   component_list))
    {
      c->add_link (get_subtables<SubTable> ()[0], c->pop_pack ());
      return_trace (true);
    }
    c->pop_discard ();
    return_trace (false);
  }

  template <typename context_t>
  static inline typename context_t::return_t dispatch_recurse_func (context_t *c, unsigned int lookup_index);

  static inline typename hb_closure_context_t::return_t closure_glyphs_recurse_func (hb_closure_context_t *c, unsigned lookup_index, hb_set_t *covered_seq_indices, unsigned seq_index, unsigned end_index);

  static inline hb_closure_context_t::return_t dispatch_closure_recurse_func (hb_closure_context_t *c, unsigned lookup_index, hb_set_t *covered_seq_indices, unsigned seq_index, unsigned end_index)
  {
    if (!c->should_visit_lookup (lookup_index))
      return hb_empty_t ();

    hb_closure_context_t::return_t ret = closure_glyphs_recurse_func (c, lookup_index, covered_seq_indices, seq_index, end_index);

    /* While in theory we should flush here, it will cause timeouts because a recursive
     * lookup can keep growing the glyph set.  Skip, and outer loop will retry up to
     * HB_CLOSURE_MAX_STAGES time, which should be enough for every realistic font. */
    //c->flush ();

    return ret;
  }

  template <typename context_t, typename ...Ts>
  typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
  { return Lookup::dispatch<SubTable> (c, std::forward<Ts> (ds)...); }

  bool subset (hb_subset_context_t *c) const
  { return Lookup::subset<SubTable> (c); }
};


}
}
}

#endif  /* OT_LAYOUT_GSUB_SUBSTLOOKUP_HH */