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 klass2 = (this+classDef2).get_class (buffer->info[skippy_iter.idx].codepoint); 143 if (!klass2) 144 { 145 buffer->unsafe_to_concat (buffer->idx, skippy_iter.idx + 1); 146 return_trace (false); 147 } 148 149 unsigned int klass1 = (this+classDef1).get_class (buffer->cur().codepoint); 150 if (unlikely (klass1 >= class1Count || klass2 >= class2Count)) 151 { 152 buffer->unsafe_to_concat (buffer->idx, skippy_iter.idx + 1); 153 return_trace (false); 154 } 155 156 unsigned int len1 = valueFormat1.get_len (); 157 unsigned int len2 = valueFormat2.get_len (); 158 unsigned int record_len = len1 + len2; 159 160 const Value *v = &values[record_len * (klass1 * class2Count + klass2)]; 161 162 bool applied_first = false, applied_second = false; 163 164 165 /* Isolate simple kerning and apply it half to each side. 166 * Results in better cursor positioning / underline drawing. 167 * 168 * Disabled, because causes issues... :-( 169 * https://github.com/harfbuzz/harfbuzz/issues/3408 170 * https://github.com/harfbuzz/harfbuzz/pull/3235#issuecomment-1029814978 171 */ 172 #ifndef HB_SPLIT_KERN 173 if (false) 174 #endif 175 { 176 if (!len2) 177 { 178 const hb_direction_t dir = buffer->props.direction; 179 const bool horizontal = HB_DIRECTION_IS_HORIZONTAL (dir); 180 const bool backward = HB_DIRECTION_IS_BACKWARD (dir); 181 unsigned mask = horizontal ? ValueFormat::xAdvance : ValueFormat::yAdvance; 182 if (backward) 183 mask |= mask >> 2; /* Add eg. xPlacement in RTL. */ 184 /* Add Devices. */ 185 mask |= mask << 4; 186 187 if (valueFormat1 & ~mask) 188 goto bail; 189 190 /* Is simple kern. Apply value on an empty position slot, 191 * then split it between sides. */ 192 193 hb_glyph_position_t pos{}; 194 if (valueFormat1.apply_value (c, this, v, pos)) 195 { 196 hb_position_t *src = &pos.x_advance; 197 hb_position_t *dst1 = &buffer->cur_pos().x_advance; 198 hb_position_t *dst2 = &buffer->pos[skippy_iter.idx].x_advance; 199 unsigned i = horizontal ? 0 : 1; 200 201 hb_position_t kern = src[i]; 202 hb_position_t kern1 = kern >> 1; 203 hb_position_t kern2 = kern - kern1; 204 205 if (!backward) 206 { 207 dst1[i] += kern1; 208 dst2[i] += kern2; 209 dst2[i + 2] += kern2; 210 } 211 else 212 { 213 dst1[i] += kern1; 214 dst1[i + 2] += src[i + 2] - kern2; 215 dst2[i] += kern2; 216 } 217 218 applied_first = applied_second = kern != 0; 219 goto success; 220 } 221 goto boring; 222 } 223 } 224 bail: 225 226 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 227 { 228 c->buffer->message (c->font, 229 "try kerning glyphs at %u,%u", 230 c->buffer->idx, skippy_iter.idx); 231 } 232 233 applied_first = len1 && valueFormat1.apply_value (c, this, v, buffer->cur_pos()); 234 applied_second = len2 && valueFormat2.apply_value (c, this, v + len1, buffer->pos[skippy_iter.idx]); 235 236 if (applied_first || applied_second) 237 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 238 { 239 c->buffer->message (c->font, 240 "kerned glyphs at %u,%u", 241 c->buffer->idx, skippy_iter.idx); 242 } 243 244 if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ()) 245 { 246 c->buffer->message (c->font, 247 "tried kerning glyphs at %u,%u", 248 c->buffer->idx, skippy_iter.idx); 249 } 250 251 success: 252 if (applied_first || applied_second) 253 buffer->unsafe_to_break (buffer->idx, skippy_iter.idx + 1); 254 else 255 boring: 256 buffer->unsafe_to_concat (buffer->idx, skippy_iter.idx + 1); 257 258 if (len2) 259 { 260 skippy_iter.idx++; 261 // https://github.com/harfbuzz/harfbuzz/issues/3824 262 // https://github.com/harfbuzz/harfbuzz/issues/3888#issuecomment-1326781116 263 buffer->unsafe_to_break (buffer->idx, skippy_iter.idx + 1); 264 } 265 266 buffer->idx = skippy_iter.idx; 267 268 return_trace (true); 269 } 270 subsetOT::Layout::GPOS_impl::PairPosFormat2_4271 bool subset (hb_subset_context_t *c) const 272 { 273 TRACE_SUBSET (this); 274 auto *out = c->serializer->start_embed (*this); 275 if (unlikely (!c->serializer->extend_min (out))) return_trace (false); 276 out->format = format; 277 278 hb_map_t klass1_map; 279 out->classDef1.serialize_subset (c, classDef1, this, &klass1_map, true, true, &(this + coverage)); 280 out->class1Count = klass1_map.get_population (); 281 282 hb_map_t klass2_map; 283 out->classDef2.serialize_subset (c, classDef2, this, &klass2_map, true, false); 284 out->class2Count = klass2_map.get_population (); 285 286 unsigned len1 = valueFormat1.get_len (); 287 unsigned len2 = valueFormat2.get_len (); 288 289 hb_pair_t<unsigned, unsigned> newFormats = hb_pair (valueFormat1, valueFormat2); 290 291 if (c->plan->normalized_coords) 292 { 293 /* in case of full instancing, all var device flags will be dropped so no 294 * need to strip hints here */ 295 newFormats = compute_effective_value_formats (klass1_map, klass2_map, false, false, &c->plan->layout_variation_idx_delta_map); 296 } 297 /* do not strip hints for VF */ 298 else if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING) 299 { 300 hb_blob_t* blob = hb_face_reference_table (c->plan->source, HB_TAG ('f','v','a','r')); 301 bool has_fvar = (blob != hb_blob_get_empty ()); 302 hb_blob_destroy (blob); 303 304 bool strip = !has_fvar; 305 /* special case: strip hints when a VF has no GDEF varstore after 306 * subsetting*/ 307 if (has_fvar && !c->plan->has_gdef_varstore) 308 strip = true; 309 newFormats = compute_effective_value_formats (klass1_map, klass2_map, strip, true); 310 } 311 312 out->valueFormat1 = newFormats.first; 313 out->valueFormat2 = newFormats.second; 314 315 unsigned total_len = len1 + len2; 316 hb_vector_t<unsigned> class2_idxs (+ hb_range ((unsigned) class2Count) | hb_filter (klass2_map)); 317 for (unsigned class1_idx : + hb_range ((unsigned) class1Count) | hb_filter (klass1_map)) 318 { 319 for (unsigned class2_idx : class2_idxs) 320 { 321 unsigned idx = (class1_idx * (unsigned) class2Count + class2_idx) * total_len; 322 valueFormat1.copy_values (c->serializer, out->valueFormat1, this, &values[idx], &c->plan->layout_variation_idx_delta_map); 323 valueFormat2.copy_values (c->serializer, out->valueFormat2, this, &values[idx + len1], &c->plan->layout_variation_idx_delta_map); 324 } 325 } 326 327 bool ret = out->coverage.serialize_subset(c, coverage, this); 328 return_trace (out->class1Count && out->class2Count && ret); 329 } 330 331 compute_effective_value_formatsOT::Layout::GPOS_impl::PairPosFormat2_4332 hb_pair_t<unsigned, unsigned> compute_effective_value_formats (const hb_map_t& klass1_map, 333 const hb_map_t& klass2_map, 334 bool strip_hints, bool strip_empty, 335 const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *varidx_delta_map = nullptr) const 336 { 337 unsigned len1 = valueFormat1.get_len (); 338 unsigned len2 = valueFormat2.get_len (); 339 unsigned record_size = len1 + len2; 340 341 unsigned format1 = 0; 342 unsigned format2 = 0; 343 344 for (unsigned class1_idx : + hb_range ((unsigned) class1Count) | hb_filter (klass1_map)) 345 { 346 for (unsigned class2_idx : + hb_range ((unsigned) class2Count) | hb_filter (klass2_map)) 347 { 348 unsigned idx = (class1_idx * (unsigned) class2Count + class2_idx) * record_size; 349 format1 = format1 | valueFormat1.get_effective_format (&values[idx], strip_hints, strip_empty, this, varidx_delta_map); 350 format2 = format2 | valueFormat2.get_effective_format (&values[idx + len1], strip_hints, strip_empty, this, varidx_delta_map); 351 } 352 353 if (format1 == valueFormat1 && format2 == valueFormat2) 354 break; 355 } 356 357 return hb_pair (format1, format2); 358 } 359 }; 360 361 } 362 } 363 } 364 365 #endif // OT_LAYOUT_GPOS_PAIRPOSFORMAT2_HH 366