src/hb-ot-layout.cc

   1 /*
   2  * Copyright (C) 1998-2004  David Turner and Werner Lemberg
   3  * Copyright (C) 2006  Behdad Esfahbod
   4  * Copyright (C) 2007,2008  Red Hat, Inc.
   5  *
   6  *  This is part of HarfBuzz, an OpenType Layout engine library.
   7  *
   8  * Permission is hereby granted, without written agreement and without
   9  * license or royalty fees, to use, copy, modify, and distribute this
  10  * software and its documentation for any purpose, provided that the
  11  * above copyright notice and the following two paragraphs appear in
  12  * all copies of this software.
  13  *
  14  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  15  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  16  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  17  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  18  * DAMAGE.
  19  *
  20  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  21  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  22  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  23  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  24  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  25  *
  26  * Red Hat Author(s): Behdad Esfahbod
  27  */
  28
  29 #define HB_OT_LAYOUT_CC
  30
  31 #include "hb-ot-layout.h"
  32 #include "hb-ot-layout-private.h"
  33
  34 #include "hb-ot-layout-open-private.h"
  35 #include "hb-ot-layout-gdef-private.h"
  36 #include "hb-ot-layout-gsub-private.h"
  37
  38 /* XXX */
  39 #include "harfbuzz-buffer-private.h"
  40
  41 #include <stdlib.h>
  42 #include <string.h>
  43
  44
  45 hb_ot_layout_t *
  46 hb_ot_layout_create (void)
  47 {
  48   hb_ot_layout_t *layout = (hb_ot_layout_t *) calloc (1, sizeof (hb_ot_layout_t));
  49
  50   layout->gdef = &Null(GDEF);
  51   layout->gsub = &Null(GSUB);
  52   layout->gpos = &/*XXX*/Null(GSUBGPOS);
  53
  54   return layout;
  55 }
  56
  57 hb_ot_layout_t *
  58 hb_ot_layout_create_for_data (const char *font_data,
  59                               int         face_index)
  60 {
  61   hb_ot_layout_t *layout;
  62
  63   if (HB_UNLIKELY (font_data == NULL))
  64     return hb_ot_layout_create ();
  65
  66   layout = (hb_ot_layout_t *) calloc (1, sizeof (hb_ot_layout_t));
  67
  68   const OpenTypeFontFile &font = OpenTypeFontFile::get_for_data (font_data);
  69   const OpenTypeFontFace &face = font.get_face (face_index);
  70
  71   layout->gdef = &GDEF::get_for_data (font.get_table_data (face.get_table_by_tag (GDEF::Tag)));
  72   layout->gsub = &GSUB::get_for_data (font.get_table_data (face.get_table_by_tag (GSUB::Tag)));
  73   layout->gpos = &/*XXX*/GSUBGPOS::get_for_data (font.get_table_data (face.get_table_by_tag (/*XXX*/GSUBGPOS::GPOSTag)));
  74
  75   return layout;
  76 }
  77
  78 void
  79 hb_ot_layout_destroy (hb_ot_layout_t *layout)
  80 {
  81   free (layout);
  82 }
  83
  84 /*
  85  * GDEF
  86  */
  87
  88 /* XXX the public class_t is a mess */
  89
  90 hb_bool_t
  91 hb_ot_layout_has_font_glyph_classes (hb_ot_layout_t *layout)
  92 {
  93   return layout->gdef->has_glyph_classes ();
  94 }
  95
  96 HB_OT_LAYOUT_INTERNAL hb_bool_t
  97 _hb_ot_layout_has_new_glyph_classes (hb_ot_layout_t *layout)
  98 {
  99   return layout->new_gdef.len > 0;
 100 }
 101
 102 HB_OT_LAYOUT_INTERNAL unsigned int
 103 _hb_ot_layout_get_glyph_property (hb_ot_layout_t *layout,
 104                                   hb_codepoint_t  glyph)
 105 {
 106   hb_ot_layout_class_t klass;
 107
 108   /* TODO old harfbuzz doesn't always parse mark attachments as it says it was
 109    * introduced without a version bump, so it may not be safe */
 110   klass = layout->gdef->get_mark_attachment_type (glyph);
 111   if (klass)
 112     return klass << 8;
 113
 114   klass = layout->gdef->get_glyph_class (glyph);
 115
 116   if (!klass && glyph < layout->new_gdef.len)
 117     klass = layout->new_gdef.klasses[glyph];
 118
 119   switch (klass) {
 120   default:
 121   case GDEF::UnclassifiedGlyph: return HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED;
 122   case GDEF::BaseGlyph:         return HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH;
 123   case GDEF::LigatureGlyph:     return HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE;
 124   case GDEF::MarkGlyph:         return HB_OT_LAYOUT_GLYPH_CLASS_MARK;
 125   case GDEF::ComponentGlyph:    return HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT;
 126   }
 127 }
 128
 129 HB_OT_LAYOUT_INTERNAL hb_bool_t
 130 _hb_ot_layout_check_glyph_property (hb_ot_layout_t *layout,
 131                                     HB_GlyphItem    gitem,
 132                                     unsigned int    lookup_flags,
 133                                     unsigned int   *property)
 134 {
 135   hb_ot_layout_glyph_class_t basic_glyph_class;
 136   unsigned int desired_attachment_class;
 137
 138   if (gitem->gproperty == HB_BUFFER_GLYPH_PROPERTIES_UNKNOWN)
 139   {
 140     gitem->gproperty = *property = _hb_ot_layout_get_glyph_property (layout, gitem->gindex);
 141     if (gitem->gproperty == HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED)
 142       return false;
 143   }
 144
 145   *property = gitem->gproperty;
 146
 147   /* If the glyph was found in the MarkAttachmentClass table,
 148    * then that class value is the high byte of the result,
 149    * otherwise the low byte contains the basic type of the glyph
 150    * as defined by the GlyphClassDef table.
 151    */
 152   if (*property & LookupFlag::MarkAttachmentType)
 153     basic_glyph_class = HB_OT_LAYOUT_GLYPH_CLASS_MARK;
 154   else
 155     basic_glyph_class = (hb_ot_layout_glyph_class_t) *property;
 156
 157   /* Not covered, if, for example, basic_glyph_class
 158    * is HB_GDEF_LIGATURE and lookup_flags includes LookupFlags::IgnoreLigatures
 159    */
 160   if (lookup_flags & basic_glyph_class)
 161     return false;
 162
 163   /* The high byte of lookup_flags has the meaning
 164    * "ignore marks of attachment type different than
 165    * the attachment type specified."
 166    */
 167   desired_attachment_class = lookup_flags & LookupFlag::MarkAttachmentType;
 168   if (desired_attachment_class)
 169   {
 170     if (basic_glyph_class == HB_OT_LAYOUT_GLYPH_CLASS_MARK &&
 171         *property != desired_attachment_class)
 172       return false;
 173   }
 174
 175   return true;
 176 }
 177
 178 HB_OT_LAYOUT_INTERNAL void
 179 _hb_ot_layout_set_glyph_property (hb_ot_layout_t *layout,
 180                                   hb_codepoint_t  glyph,
 181                                   unsigned int    property)
 182 {
 183   hb_ot_layout_glyph_class_t klass;
 184
 185   if (property & LookupFlag::MarkAttachmentType)
 186     klass = HB_OT_LAYOUT_GLYPH_CLASS_MARK;
 187   else
 188     klass = (hb_ot_layout_glyph_class_t) property;
 189
 190   hb_ot_layout_set_glyph_class (layout, glyph, klass);
 191 }
 192
 193
 194 hb_ot_layout_glyph_class_t
 195 hb_ot_layout_get_glyph_class (hb_ot_layout_t *layout,
 196                               hb_codepoint_t  glyph)
 197 {
 198   unsigned int property;
 199   hb_ot_layout_class_t klass;
 200
 201   property = _hb_ot_layout_get_glyph_property (layout, glyph);
 202
 203   if (property & LookupFlag::MarkAttachmentType)
 204     return HB_OT_LAYOUT_GLYPH_CLASS_MARK;
 205
 206   return (hb_ot_layout_glyph_class_t) property;
 207 }
 208
 209 void
 210 hb_ot_layout_set_glyph_class (hb_ot_layout_t             *layout,
 211                               hb_codepoint_t              glyph,
 212                               hb_ot_layout_glyph_class_t  klass)
 213 {
 214   /* TODO optimize this, similar to old harfbuzz code for example */
 215
 216   hb_ot_layout_class_t gdef_klass;
 217   int len = layout->new_gdef.len;
 218
 219   if (G_UNLIKELY (glyph > 65535))
 220     return;
 221
 222   if (glyph >= len) {
 223     int new_len;
 224     unsigned char *new_klasses;
 225
 226     new_len = len == 0 ? 120 : 2 * len;
 227     if (new_len > 65535)
 228       new_len = 65535;
 229     new_klasses = (unsigned char *) realloc (layout->new_gdef.klasses, new_len * sizeof (unsigned char));
 230
 231     if (G_UNLIKELY (!new_klasses))
 232       return;
 233
 234     memset (new_klasses + len, 0, new_len - len);
 235
 236     layout->new_gdef.klasses = new_klasses;
 237     layout->new_gdef.len = new_len;
 238   }
 239
 240   switch (klass) {
 241   default:
 242   case HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED:   gdef_klass = GDEF::UnclassifiedGlyph;   break;
 243   case HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH:     gdef_klass = GDEF::BaseGlyph;           break;
 244   case HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE:       gdef_klass = GDEF::LigatureGlyph;       break;
 245   case HB_OT_LAYOUT_GLYPH_CLASS_MARK:           gdef_klass = GDEF::MarkGlyph;           break;
 246   case HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT:      gdef_klass = GDEF::ComponentGlyph;      break;
 247   }
 248
 249   layout->new_gdef.klasses[glyph] = gdef_klass;
 250   return;
 251 }
 252
 253 void
 254 hb_ot_layout_build_glyph_classes (hb_ot_layout_t *layout,
 255                                   uint16_t        num_total_glyphs,
 256                                   hb_codepoint_t *glyphs,
 257                                   unsigned char  *klasses,
 258                                   uint16_t        count)
 259 {
 260   int i;
 261
 262   if (G_UNLIKELY (!count || !glyphs || !klasses))
 263     return;
 264
 265   if (layout->new_gdef.len == 0) {
 266     layout->new_gdef.klasses = (unsigned char *) calloc (num_total_glyphs, sizeof (unsigned char));
 267     layout->new_gdef.len = count;
 268   }
 269
 270   for (i = 0; i < count; i++)
 271     hb_ot_layout_set_glyph_class (layout, glyphs[i], (hb_ot_layout_glyph_class_t) klasses[i]);
 272 }
 273
 274 /*
 275  * GSUB/GPOS
 276  */
 277
 278 static const GSUBGPOS&
 279 get_gsubgpos_table (hb_ot_layout_t            *layout,
 280                     hb_ot_layout_table_type_t  table_type)
 281 {
 282   switch (table_type) {
 283     case HB_OT_LAYOUT_TABLE_TYPE_GSUB: return *(layout->gsub);
 284     case HB_OT_LAYOUT_TABLE_TYPE_GPOS: return *(layout->gpos);
 285     default:                           return Null(GSUBGPOS);
 286   }
 287 }
 288
 289
 290 unsigned int
 291 hb_ot_layout_table_get_script_count (hb_ot_layout_t            *layout,
 292                                      hb_ot_layout_table_type_t  table_type)
 293 {
 294   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 295
 296   return g.get_script_count ();
 297 }
 298
 299 hb_tag_t
 300 hb_ot_layout_table_get_script_tag (hb_ot_layout_t            *layout,
 301                                    hb_ot_layout_table_type_t  table_type,
 302                                    unsigned int               script_index)
 303 {
 304   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 305
 306   return g.get_script_tag (script_index);
 307 }
 308
 309 hb_bool_t
 310 hb_ot_layout_table_find_script (hb_ot_layout_t            *layout,
 311                                 hb_ot_layout_table_type_t  table_type,
 312                                 hb_tag_t                   script_tag,
 313                                 unsigned int              *script_index)
 314 {
 315   ASSERT_STATIC (NO_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX);
 316   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 317
 318   if (g.find_script_index (script_tag, script_index))
 319     return TRUE;
 320
 321   /* try finding 'DFLT' */
 322   if (g.find_script_index (HB_OT_LAYOUT_TAG_DEFAULT_SCRIPT, script_index))
 323     return FALSE;
 324
 325   /* try with 'dflt'; MS site has had typos and many fonts use it now :( */
 326   if (g.find_script_index (HB_OT_LAYOUT_TAG_DEFAULT_LANGUAGE, script_index))
 327     return FALSE;
 328
 329   if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
 330   return FALSE;
 331 }
 332
 333 unsigned int
 334 hb_ot_layout_table_get_feature_count (hb_ot_layout_t            *layout,
 335                                       hb_ot_layout_table_type_t  table_type)
 336 {
 337   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 338
 339   return g.get_feature_count ();
 340 }
 341
 342 hb_tag_t
 343 hb_ot_layout_table_get_feature_tag (hb_ot_layout_t            *layout,
 344                                     hb_ot_layout_table_type_t  table_type,
 345                                     unsigned int               feature_index)
 346 {
 347   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 348
 349   return g.get_feature_tag (feature_index);
 350 }
 351
 352 hb_bool_t
 353 hb_ot_layout_table_find_feature (hb_ot_layout_t            *layout,
 354                                  hb_ot_layout_table_type_t  table_type,
 355                                  hb_tag_t                   feature_tag,
 356                                  unsigned int              *feature_index)
 357 {
 358   ASSERT_STATIC (NO_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX);
 359   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 360
 361   if (g.find_feature_index (feature_tag, feature_index))
 362     return TRUE;
 363
 364   if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX;
 365   return FALSE;
 366 }
 367
 368 unsigned int
 369 hb_ot_layout_table_get_lookup_count (hb_ot_layout_t            *layout,
 370                                      hb_ot_layout_table_type_t  table_type)
 371 {
 372   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 373
 374   return g.get_lookup_count ();
 375 }
 376
 377
 378 unsigned int
 379 hb_ot_layout_script_get_language_count (hb_ot_layout_t            *layout,
 380                                         hb_ot_layout_table_type_t  table_type,
 381                                         unsigned int               script_index)
 382 {
 383   const Script &s = get_gsubgpos_table (layout, table_type).get_script (script_index);
 384
 385   return s.get_lang_sys_count ();
 386 }
 387
 388 hb_tag_t
 389 hb_ot_layout_script_get_language_tag (hb_ot_layout_t            *layout,
 390                                       hb_ot_layout_table_type_t  table_type,
 391                                       unsigned int               script_index,
 392                                       unsigned int               language_index)
 393 {
 394   const Script &s = get_gsubgpos_table (layout, table_type).get_script (script_index);
 395
 396   return s.get_lang_sys_tag (language_index);
 397 }
 398
 399 hb_bool_t
 400 hb_ot_layout_script_find_language (hb_ot_layout_t            *layout,
 401                                    hb_ot_layout_table_type_t  table_type,
 402                                    unsigned int               script_index,
 403                                    hb_tag_t                   language_tag,
 404                                    unsigned int              *language_index)
 405 {
 406   ASSERT_STATIC (NO_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX);
 407   const Script &s = get_gsubgpos_table (layout, table_type).get_script (script_index);
 408
 409   if (s.find_lang_sys_index (language_tag, language_index))
 410     return TRUE;
 411
 412   /* try with 'dflt'; MS site has had typos and many fonts use it now :( */
 413   if (s.find_lang_sys_index (HB_OT_LAYOUT_TAG_DEFAULT_LANGUAGE, language_index))
 414     return FALSE;
 415
 416   if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX;
 417   return FALSE;
 418 }
 419
 420 hb_bool_t
 421 hb_ot_layout_language_get_required_feature_index (hb_ot_layout_t            *layout,
 422                                                   hb_ot_layout_table_type_t  table_type,
 423                                                   unsigned int               script_index,
 424                                                   unsigned int               language_index,
 425                                                   unsigned int              *feature_index)
 426 {
 427   const LangSys &l = get_gsubgpos_table (layout, table_type).get_script (script_index).get_lang_sys (language_index);
 428
 429   if (feature_index) *feature_index = l.get_required_feature_index ();
 430
 431   return l.has_required_feature ();
 432 }
 433
 434 unsigned int
 435 hb_ot_layout_language_get_feature_count (hb_ot_layout_t            *layout,
 436                                          hb_ot_layout_table_type_t  table_type,
 437                                          unsigned int               script_index,
 438                                          unsigned int               language_index)
 439 {
 440   const LangSys &l = get_gsubgpos_table (layout, table_type).get_script (script_index).get_lang_sys (language_index);
 441
 442   return l.get_feature_count ();
 443 }
 444
 445 unsigned int
 446 hb_ot_layout_language_get_feature_index (hb_ot_layout_t            *layout,
 447                                          hb_ot_layout_table_type_t  table_type,
 448                                          unsigned int               script_index,
 449                                          unsigned int               language_index,
 450                                          unsigned int               num_feature)
 451 {
 452   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 453   const LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
 454
 455   return l.get_feature_index (num_feature);
 456 }
 457
 458 hb_tag_t
 459 hb_ot_layout_language_get_feature_tag (hb_ot_layout_t            *layout,
 460                                        hb_ot_layout_table_type_t  table_type,
 461                                        unsigned int               script_index,
 462                                        unsigned int               language_index,
 463                                        unsigned int               num_feature)
 464 {
 465   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 466   const LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
 467   unsigned int feature_index = l.get_feature_index (num_feature);
 468
 469   return g.get_feature_tag (feature_index);
 470 }
 471
 472
 473 hb_bool_t
 474 hb_ot_layout_language_find_feature (hb_ot_layout_t            *layout,
 475                                     hb_ot_layout_table_type_t  table_type,
 476                                     unsigned int               script_index,
 477                                     unsigned int               language_index,
 478                                     hb_tag_t                   feature_tag,
 479                                     unsigned int              *feature_index)
 480 {
 481   ASSERT_STATIC (NO_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX);
 482   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 483   const LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
 484   unsigned int i;
 485
 486   for (i = 0; i < l.get_feature_count (); i++) {
 487     unsigned int f_index = l.get_feature_index (i);
 488
 489     if (feature_tag == g.get_feature_tag (f_index)) {
 490       if (feature_index) *feature_index = f_index;
 491       return TRUE;
 492     }
 493   }
 494
 495   if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX;
 496   return FALSE;
 497 }
 498
 499 unsigned int
 500 hb_ot_layout_feature_get_lookup_count (hb_ot_layout_t            *layout,
 501                                        hb_ot_layout_table_type_t  table_type,
 502                                        unsigned int               feature_index)
 503 {
 504   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 505   const Feature &f = g.get_feature (feature_index);
 506
 507   return f.get_lookup_count ();
 508 }
 509
 510 unsigned int
 511 hb_ot_layout_feature_get_lookup_index (hb_ot_layout_t            *layout,
 512                                        hb_ot_layout_table_type_t  table_type,
 513                                        unsigned int               feature_index,
 514                                        unsigned int               num_lookup)
 515 {
 516   const GSUBGPOS &g = get_gsubgpos_table (layout, table_type);
 517   const Feature &f = g.get_feature (feature_index);
 518
 519   return f.get_lookup_index (num_lookup);
 520 }
 521
 522 /*
 523  * GSUB
 524  */
 525
 526 hb_bool_t
 527 hb_ot_layout_substitute_lookup (hb_ot_layout_t              *layout,
 528                                 hb_buffer_t                 *buffer,
 529                                 unsigned int                 lookup_index,
 530                                 hb_ot_layout_feature_mask_t  mask)
 531 {
 532   return layout->gsub->substitute_lookup (layout, buffer, lookup_index, mask);
 533 }
 534
 535
 536
 537 /* XXX dupped, until he old code can be removed */
 538
 539 static HB_Error
 540 hb_buffer_duplicate_out_buffer( HB_Buffer buffer )
 541 {
 542   if ( !buffer->alt_string )
 543     {
 544       HB_Error error;
 545
 546       if ( ALLOC_ARRAY( buffer->alt_string, buffer->allocated, HB_GlyphItemRec ) )
 547         return error;
 548     }
 549
 550   buffer->out_string = buffer->alt_string;
 551   memcpy( buffer->out_string, buffer->in_string, buffer->out_length * sizeof (buffer->out_string[0]) );
 552   buffer->separate_out = TRUE;
 553
 554   return HB_Err_Ok;
 555 }
 556
 557
 558
 559 HB_INTERNAL HB_Error
 560 _hb_buffer_add_output_glyph_ids( HB_Buffer  buffer,
 561                               HB_UShort  num_in,
 562                               HB_UShort  num_out,
 563                               const GlyphID *glyph_data,
 564                               HB_UShort  component,
 565                               HB_UShort  ligID )
 566 {
 567   HB_Error  error;
 568   HB_UShort i;
 569   HB_UInt properties;
 570   HB_UInt cluster;
 571
 572   error = hb_buffer_ensure( buffer, buffer->out_pos + num_out );
 573   if ( error )
 574     return error;
 575
 576   if ( !buffer->separate_out )
 577     {
 578       error = hb_buffer_duplicate_out_buffer( buffer );
 579       if ( error )
 580         return error;
 581     }
 582
 583   properties = buffer->in_string[buffer->in_pos].properties;
 584   cluster = buffer->in_string[buffer->in_pos].cluster;
 585   if ( component == 0xFFFF )
 586     component = buffer->in_string[buffer->in_pos].component;
 587   if ( ligID == 0xFFFF )
 588     ligID = buffer->in_string[buffer->in_pos].ligID;
 589
 590   for ( i = 0; i < num_out; i++ )
 591   {
 592     HB_GlyphItem item = &buffer->out_string[buffer->out_pos + i];
 593
 594     item->gindex = glyph_data[i];
 595     item->properties = properties;
 596     item->cluster = cluster;
 597     item->component = component;
 598     item->ligID = ligID;
 599     item->gproperty = HB_GLYPH_PROPERTY_UNKNOWN;
 600   }
 601
 602   buffer->in_pos  += num_in;
 603   buffer->out_pos += num_out;
 604
 605   buffer->out_length = buffer->out_pos;
 606
 607   return HB_Err_Ok;
 608 }
 609