SingleSubstFormat2.hh (5291B)
1 #ifndef OT_LAYOUT_GSUB_SINGLESUBSTFORMAT2_HH 2 #define OT_LAYOUT_GSUB_SINGLESUBSTFORMAT2_HH 3 4 #include "Common.hh" 5 6 namespace OT { 7 namespace Layout { 8 namespace GSUB_impl { 9 10 template <typename Types> 11 struct SingleSubstFormat2_4 12 { 13 protected: 14 HBUINT16 format; /* Format identifier--format = 2 */ 15 typename Types::template OffsetTo<Coverage> 16 coverage; /* Offset to Coverage table--from 17 * beginning of Substitution table */ 18 Array16Of<typename Types::HBGlyphID> 19 substitute; /* Array of substitute 20 * GlyphIDs--ordered by Coverage Index */ 21 22 public: 23 DEFINE_SIZE_ARRAY (4 + Types::size, substitute); 24 25 bool sanitize (hb_sanitize_context_t *c) const 26 { 27 TRACE_SANITIZE (this); 28 return_trace (coverage.sanitize (c, this) && substitute.sanitize (c)); 29 } 30 31 bool intersects (const hb_set_t *glyphs) const 32 { return (this+coverage).intersects (glyphs); } 33 34 bool may_have_non_1to1 () const 35 { return false; } 36 37 void closure (hb_closure_context_t *c) const 38 { 39 auto &cov = this+coverage; 40 auto &glyph_set = c->parent_active_glyphs (); 41 42 if (substitute.len > glyph_set.get_population () * 4) 43 { 44 for (auto g : glyph_set) 45 { 46 unsigned i = cov.get_coverage (g); 47 if (i == NOT_COVERED || i >= substitute.len) 48 continue; 49 c->output->add (substitute.arrayZ[i]); 50 } 51 52 return; 53 } 54 55 + hb_zip (cov, substitute) 56 | hb_filter (glyph_set, hb_first) 57 | hb_map (hb_second) 58 | hb_sink (c->output) 59 ; 60 } 61 62 void closure_lookups (hb_closure_lookups_context_t *c) const {} 63 64 void collect_glyphs (hb_collect_glyphs_context_t *c) const 65 { 66 if (unlikely (!(this+coverage).collect_coverage (c->input))) return; 67 + hb_zip (this+coverage, substitute) 68 | hb_map (hb_second) 69 | hb_sink (c->output) 70 ; 71 } 72 73 const Coverage &get_coverage () const { return this+coverage; } 74 75 bool would_apply (hb_would_apply_context_t *c) const 76 { return c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED; } 77 78 unsigned 79 get_glyph_alternates (hb_codepoint_t glyph_id, 80 unsigned start_offset, 81 unsigned *alternate_count /* IN/OUT. May be NULL. */, 82 hb_codepoint_t *alternate_glyphs /* OUT. May be NULL. */) const 83 { 84 unsigned int index = (this+coverage).get_coverage (glyph_id); 85 if (likely (index == NOT_COVERED)) 86 { 87 if (alternate_count) 88 *alternate_count = 0; 89 return 0; 90 } 91 92 if (alternate_count && *alternate_count) 93 { 94 glyph_id = substitute[index]; 95 96 *alternate_glyphs = glyph_id; 97 *alternate_count = 1; 98 } 99 100 return 1; 101 } 102 103 void 104 collect_glyph_alternates (hb_map_t *alternate_count /* IN/OUT */, 105 hb_map_t *alternate_glyphs /* IN/OUT */) const 106 { 107 + hb_zip (this+coverage, substitute) 108 | hb_apply ([&] (const hb_pair_t<hb_codepoint_t, hb_codepoint_t> &p) -> void 109 { _hb_collect_glyph_alternates_add (p.first, p.second, 110 alternate_count, alternate_glyphs); }) 111 ; 112 } 113 114 bool apply (hb_ot_apply_context_t *c) const 115 { 116 TRACE_APPLY (this); 117 unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint); 118 if (index == NOT_COVERED) return_trace (false); 119 120 if (unlikely (index >= substitute.len)) return_trace (false); 121 122 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 123 { 124 c->buffer->sync_so_far (); 125 c->buffer->message (c->font, 126 "replacing glyph at %u (single substitution)", 127 c->buffer->idx); 128 } 129 130 c->replace_glyph (substitute[index]); 131 132 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 133 { 134 c->buffer->message (c->font, 135 "replaced glyph at %u (single substitution)", 136 c->buffer->idx - 1u); 137 } 138 139 return_trace (true); 140 } 141 142 template<typename Iterator, 143 hb_requires (hb_is_sorted_source_of (Iterator, 144 hb_codepoint_pair_t))> 145 bool serialize (hb_serialize_context_t *c, 146 Iterator it) 147 { 148 TRACE_SERIALIZE (this); 149 auto substitutes = 150 + it 151 | hb_map (hb_second) 152 ; 153 auto glyphs = 154 + it 155 | hb_map_retains_sorting (hb_first) 156 ; 157 if (unlikely (!c->extend_min (this))) return_trace (false); 158 if (unlikely (!substitute.serialize (c, substitutes))) return_trace (false); 159 if (unlikely (!coverage.serialize_serialize (c, glyphs))) return_trace (false); 160 return_trace (true); 161 } 162 163 bool subset (hb_subset_context_t *c) const 164 { 165 TRACE_SUBSET (this); 166 const hb_set_t &glyphset = *c->plan->glyphset_gsub (); 167 const hb_map_t &glyph_map = *c->plan->glyph_map; 168 169 auto it = 170 + hb_zip (this+coverage, substitute) 171 | hb_filter (glyphset, hb_first) 172 | hb_filter (glyphset, hb_second) 173 | hb_map_retains_sorting ([&] (hb_pair_t<hb_codepoint_t, const typename Types::HBGlyphID &> p) -> hb_codepoint_pair_t 174 { return hb_pair (glyph_map[p.first], glyph_map[p.second]); }) 175 ; 176 177 bool ret = bool (it); 178 SingleSubst_serialize (c->serializer, it); 179 return_trace (ret); 180 } 181 }; 182 183 } 184 } 185 } 186 187 #endif /* OT_LAYOUT_GSUB_SINGLESUBSTFORMAT2_HH */