1 #ifndef OT_LAYOUT_GPOS_PAIRPOSFORMAT2_HH 2 #define OT_LAYOUT_GPOS_PAIRPOSFORMAT2_HH 3 4 #include "ValueFormat.hh" 5 6 namespace OT { 7 namespace Layout { 8 namespace GPOS_impl { 9 10 template <typename Types> 11 struct PairPosFormat2_4 : ValueBase 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 subtable */ 18 ValueFormat valueFormat1; /* ValueRecord definition--for the 19 * first glyph of the pair--may be zero 20 * (0) */ 21 ValueFormat valueFormat2; /* ValueRecord definition--for the 22 * second glyph of the pair--may be 23 * zero (0) */ 24 typename Types::template OffsetTo<ClassDef> 25 classDef1; /* Offset to ClassDef table--from 26 * beginning of PairPos subtable--for 27 * the first glyph of the pair */ 28 typename Types::template OffsetTo<ClassDef> 29 classDef2; /* Offset to ClassDef table--from 30 * beginning of PairPos subtable--for 31 * the second glyph of the pair */ 32 HBUINT16 class1Count; /* Number of classes in ClassDef1 33 * table--includes Class0 */ 34 HBUINT16 class2Count; /* Number of classes in ClassDef2 35 * table--includes Class0 */ 36 ValueRecord values; /* Matrix of value pairs: 37 * class1-major, class2-minor, 38 * Each entry has value1 and value2 */ 39 public: 40 DEFINE_SIZE_ARRAY (10 + 3 * Types::size, values); 41 sanitizeOT::Layout::GPOS_impl::PairPosFormat2_442 bool sanitize (hb_sanitize_context_t *c) const 43 { 44 TRACE_SANITIZE (this); 45 if (!(c->check_struct (this) 46 && coverage.sanitize (c, this) 47 && classDef1.sanitize (c, this) 48 && classDef2.sanitize (c, this))) return_trace (false); 49 50 unsigned int len1 = valueFormat1.get_len (); 51 unsigned int len2 = valueFormat2.get_len (); 52 unsigned int stride = HBUINT16::static_size * (len1 + len2); 53 unsigned int count = (unsigned int) class1Count * (unsigned int) class2Count; 54 return_trace (c->check_range ((const void *) values, 55 count, 56 stride) && 57 (c->lazy_some_gpos || 58 (valueFormat1.sanitize_values_stride_unsafe (c, this, &values[0], count, stride) && 59 valueFormat2.sanitize_values_stride_unsafe (c, this, &values[len1], count, stride)))); 60 } 61 intersectsOT::Layout::GPOS_impl::PairPosFormat2_462 bool intersects (const hb_set_t *glyphs) const 63 { 64 return (this+coverage).intersects (glyphs) && 65 (this+classDef2).intersects (glyphs); 66 } 67 closure_lookupsOT::Layout::GPOS_impl::PairPosFormat2_468 void closure_lookups (hb_closure_lookups_context_t *c) const {} collect_variation_indicesOT::Layout::GPOS_impl::PairPosFormat2_469 void collect_variation_indices (hb_collect_variation_indices_context_t *c) const 70 { 71 if (!intersects (c->glyph_set)) return; 72 if ((!valueFormat1.has_device ()) && (!valueFormat2.has_device ())) return; 73 74 hb_set_t klass1_glyphs, klass2_glyphs; 75 if (!(this+classDef1).collect_coverage (&klass1_glyphs)) return; 76 if (!(this+classDef2).collect_coverage (&klass2_glyphs)) return; 77 78 hb_set_t class1_set, class2_set; 79 for (const unsigned cp : + c->glyph_set->iter () | hb_filter (this + coverage)) 80 { 81 if (!klass1_glyphs.has (cp)) class1_set.add (0); 82 else 83 { 84 unsigned klass1 = (this+classDef1).get (cp); 85 class1_set.add (klass1); 86 } 87 } 88 89 class2_set.add (0); 90 for (const unsigned cp : + c->glyph_set->iter () | hb_filter (klass2_glyphs)) 91 { 92 unsigned klass2 = (this+classDef2).get (cp); 93 class2_set.add (klass2); 94 } 95 96 if (class1_set.is_empty () 97 || class2_set.is_empty () 98 || (class2_set.get_population() == 1 && class2_set.has(0))) 99 return; 100 101 unsigned len1 = valueFormat1.get_len (); 102 unsigned len2 = valueFormat2.get_len (); 103 const hb_array_t<const Value> values_array = values.as_array ((unsigned)class1Count * (unsigned) class2Count * (len1 + len2)); 104 for (const unsigned class1_idx : class1_set.iter ()) 105 { 106 for (const unsigned class2_idx : class2_set.iter ()) 107 { 108 unsigned start_offset = (class1_idx * (unsigned) class2Count + class2_idx) * (len1 + len2); 109 if (valueFormat1.has_device ()) 110 valueFormat1.collect_variation_indices (c, this, values_array.sub_array (start_offset, len1)); 111 112 if (valueFormat2.has_device ()) 113 valueFormat2.collect_variation_indices (c, this, values_array.sub_array (start_offset+len1, len2)); 114 } 115 } 116 } 117 collect_glyphsOT::Layout::GPOS_impl::PairPosFormat2_4118 void collect_glyphs (hb_collect_glyphs_context_t *c) const 119 { 120 if (unlikely (!(this+coverage).collect_coverage (c->input))) return; 121 if (unlikely (!(this+classDef2).collect_coverage (c->input))) return; 122 } 123 get_coverageOT::Layout::GPOS_impl::PairPosFormat2_4124 const Coverage &get_coverage () const { return this+coverage; } 125 applyOT::Layout::GPOS_impl::PairPosFormat2_4126 bool apply (hb_ot_apply_context_t *c) const 127 { 128 TRACE_APPLY (this); 129 hb_buffer_t *buffer = c->buffer; 130 unsigned int index = (this+coverage).get_coverage (buffer->cur().codepoint); 131 if (likely (index == NOT_COVERED)) return_trace (false); 132 133 hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input; 134 skippy_iter.reset_fast (buffer->idx); 135 unsigned unsafe_to; 136 if (unlikely (!skippy_iter.next (&unsafe_to))) 137 { 138 buffer->unsafe_to_concat (buffer->idx, unsafe_to); 139 return_trace (false); 140 } 141 142 unsigned int klass1 = (this+classDef1).get_class (buffer->cur().codepoint); 143 unsigned int klass2 = (this+classDef2).get_class (buffer->info[skippy_iter.idx].codepoint); 144 if (unlikely (klass1 >= class1Count || klass2 >= class2Count)) 145 { 146 buffer->unsafe_to_concat (buffer->idx, skippy_iter.idx + 1); 147 return_trace (false); 148 } 149 150 unsigned int len1 = valueFormat1.get_len (); 151 unsigned int len2 = valueFormat2.get_len (); 152 unsigned int record_len = len1 + len2; 153 154 const Value *v = &values[record_len * (klass1 * class2Count + klass2)]; 155 156 bool applied_first = false, applied_second = false; 157 158 159 /* Isolate simple kerning and apply it half to each side. 160 * Results in better cursor positioning / underline drawing. 161 * 162 * Disabled, because causes issues... :-( 163 * https://github.com/harfbuzz/harfbuzz/issues/3408 164 * https://github.com/harfbuzz/harfbuzz/pull/3235#issuecomment-1029814978 165 */ 166 #ifndef HB_SPLIT_KERN 167 if (false) 168 #endif 169 { 170 if (!len2) 171 { 172 const hb_direction_t dir = buffer->props.direction; 173 const bool horizontal = HB_DIRECTION_IS_HORIZONTAL (dir); 174 const bool backward = HB_DIRECTION_IS_BACKWARD (dir); 175 unsigned mask = horizontal ? ValueFormat::xAdvance : ValueFormat::yAdvance; 176 if (backward) 177 mask |= mask >> 2; /* Add eg. xPlacement in RTL. */ 178 /* Add Devices. */ 179 mask |= mask << 4; 180 181 if (valueFormat1 & ~mask) 182 goto bail; 183 184 /* Is simple kern. Apply value on an empty position slot, 185 * then split it between sides. */ 186 187 hb_glyph_position_t pos{}; 188 if (valueFormat1.apply_value (c, this, v, pos)) 189 { 190 hb_position_t *src = &pos.x_advance; 191 hb_position_t *dst1 = &buffer->cur_pos().x_advance; 192 hb_position_t *dst2 = &buffer->pos[skippy_iter.idx].x_advance; 193 unsigned i = horizontal ? 0 : 1; 194 195 hb_position_t kern = src[i]; 196 hb_position_t kern1 = kern >> 1; 197 hb_position_t kern2 = kern - kern1; 198 199 if (!backward) 200 { 201 dst1[i] += kern1; 202 dst2[i] += kern2; 203 dst2[i + 2] += kern2; 204 } 205 else 206 { 207 dst1[i] += kern1; 208 dst1[i + 2] += src[i + 2] - kern2; 209 dst2[i] += kern2; 210 } 211 212 applied_first = applied_second = kern != 0; 213 goto success; 214 } 215 goto boring; 216 } 217 } 218 bail: 219 220 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 221 { 222 c->buffer->message (c->font, 223 "try kerning glyphs at %u,%u", 224 c->buffer->idx, skippy_iter.idx); 225 } 226 227 applied_first = len1 && valueFormat1.apply_value (c, this, v, buffer->cur_pos()); 228 applied_second = len2 && valueFormat2.apply_value (c, this, v + len1, buffer->pos[skippy_iter.idx]); 229 230 if (applied_first || applied_second) 231 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 232 { 233 c->buffer->message (c->font, 234 "kerned glyphs at %u,%u", 235 c->buffer->idx, skippy_iter.idx); 236 } 237 238 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 239 { 240 c->buffer->message (c->font, 241 "tried kerning glyphs at %u,%u", 242 c->buffer->idx, skippy_iter.idx); 243 } 244 245 success: 246 if (applied_first || applied_second) 247 buffer->unsafe_to_break (buffer->idx, skippy_iter.idx + 1); 248 else 249 boring: 250 buffer->unsafe_to_concat (buffer->idx, skippy_iter.idx + 1); 251 252 if (len2) 253 { 254 skippy_iter.idx++; 255 // https://github.com/harfbuzz/harfbuzz/issues/3824 256 // https://github.com/harfbuzz/harfbuzz/issues/3888#issuecomment-1326781116 257 buffer->unsafe_to_break (buffer->idx, skippy_iter.idx + 1); 258 } 259 260 buffer->idx = skippy_iter.idx; 261 262 return_trace (true); 263 } 264 subsetOT::Layout::GPOS_impl::PairPosFormat2_4265 bool subset (hb_subset_context_t *c) const 266 { 267 TRACE_SUBSET (this); 268 auto *out = c->serializer->start_embed (*this); 269 if (unlikely (!c->serializer->extend_min (out))) return_trace (false); 270 out->format = format; 271 272 hb_map_t klass1_map; 273 out->classDef1.serialize_subset (c, classDef1, this, &klass1_map, true, true, &(this + coverage)); 274 out->class1Count = klass1_map.get_population (); 275 276 hb_map_t klass2_map; 277 out->classDef2.serialize_subset (c, classDef2, this, &klass2_map, true, false); 278 out->class2Count = klass2_map.get_population (); 279 280 unsigned len1 = valueFormat1.get_len (); 281 unsigned len2 = valueFormat2.get_len (); 282 283 hb_pair_t<unsigned, unsigned> newFormats = hb_pair (valueFormat1, valueFormat2); 284 285 if (c->plan->normalized_coords) 286 { 287 /* in case of full instancing, all var device flags will be dropped so no 288 * need to strip hints here */ 289 newFormats = compute_effective_value_formats (klass1_map, klass2_map, false, false, &c->plan->layout_variation_idx_delta_map); 290 } 291 /* do not strip hints for VF */ 292 else if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING) 293 { 294 hb_blob_t* blob = hb_face_reference_table (c->plan->source, HB_TAG ('f','v','a','r')); 295 bool has_fvar = (blob != hb_blob_get_empty ()); 296 hb_blob_destroy (blob); 297 298 bool strip = !has_fvar; 299 /* special case: strip hints when a VF has no GDEF varstore after 300 * subsetting*/ 301 if (has_fvar && !c->plan->has_gdef_varstore) 302 strip = true; 303 newFormats = compute_effective_value_formats (klass1_map, klass2_map, strip, true); 304 } 305 306 out->valueFormat1 = newFormats.first; 307 out->valueFormat2 = newFormats.second; 308 309 unsigned total_len = len1 + len2; 310 hb_vector_t<unsigned> class2_idxs (+ hb_range ((unsigned) class2Count) | hb_filter (klass2_map)); 311 for (unsigned class1_idx : + hb_range ((unsigned) class1Count) | hb_filter (klass1_map)) 312 { 313 for (unsigned class2_idx : class2_idxs) 314 { 315 unsigned idx = (class1_idx * (unsigned) class2Count + class2_idx) * total_len; 316 valueFormat1.copy_values (c->serializer, out->valueFormat1, this, &values[idx], &c->plan->layout_variation_idx_delta_map); 317 valueFormat2.copy_values (c->serializer, out->valueFormat2, this, &values[idx + len1], &c->plan->layout_variation_idx_delta_map); 318 } 319 } 320 321 bool ret = out->coverage.serialize_subset(c, coverage, this); 322 return_trace (out->class1Count && out->class2Count && ret); 323 } 324 325 compute_effective_value_formatsOT::Layout::GPOS_impl::PairPosFormat2_4326 hb_pair_t<unsigned, unsigned> compute_effective_value_formats (const hb_map_t& klass1_map, 327 const hb_map_t& klass2_map, 328 bool strip_hints, bool strip_empty, 329 const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *varidx_delta_map = nullptr) const 330 { 331 unsigned len1 = valueFormat1.get_len (); 332 unsigned len2 = valueFormat2.get_len (); 333 unsigned record_size = len1 + len2; 334 335 unsigned format1 = 0; 336 unsigned format2 = 0; 337 338 for (unsigned class1_idx : + hb_range ((unsigned) class1Count) | hb_filter (klass1_map)) 339 { 340 for (unsigned class2_idx : + hb_range ((unsigned) class2Count) | hb_filter (klass2_map)) 341 { 342 unsigned idx = (class1_idx * (unsigned) class2Count + class2_idx) * record_size; 343 format1 = format1 | valueFormat1.get_effective_format (&values[idx], strip_hints, strip_empty, this, varidx_delta_map); 344 format2 = format2 | valueFormat2.get_effective_format (&values[idx + len1], strip_hints, strip_empty, this, varidx_delta_map); 345 } 346 347 if (format1 == valueFormat1 && format2 == valueFormat2) 348 break; 349 } 350 351 return hb_pair (format1, format2); 352 } 353 }; 354 355 } 356 } 357 } 358 359 #endif // OT_LAYOUT_GPOS_PAIRPOSFORMAT2_HH 360