(print_anchor, print_glyph_positioning): New functions.
[m17n/libotf.git] / src / otfdrive.c
index 763d847..0b2ef60 100644 (file)
@@ -29,6 +29,8 @@ write to the Free Software Foundation, Inc., 59 Temple Place, Suite
 #include "otf.h"
 #include "otferror.h"
 
+extern int debug_flag;
+
 /* Return nonzero (-1 if ID is zero, 1 otherwise) if OTF_Glyph *G
    should be ignored according to LookupFlag FLAG.  */
 #define IGNORED_GLYPH(g, flag)                         \
@@ -771,6 +773,65 @@ gstring_insert_for_gpos (OTF_GlyphString *gstring, int gidx)
   return gidx;
 }
 
+static void
+print_anchor (char *head, OTF_Anchor *anchor)
+{
+  if (anchor->AnchorFormat == 1)
+    fprintf (stderr, " %s(X:%d Y:%d)", head,
+            anchor->XCoordinate, anchor->YCoordinate);
+  else if (anchor->AnchorFormat == 2)
+    fprintf (stderr, " %s(X:%d Y:%d AP:%d)", head,
+            anchor->XCoordinate, anchor->YCoordinate,
+            anchor->f.f1.AnchorPoint);
+  else
+    fprintf (stderr, " %s(X:%d Y:%d +alpha)", head,
+            anchor->XCoordinate, anchor->YCoordinate);
+}
+
+static void
+print_glyph_positioning (OTF_Glyph *g, int type)
+{
+  if (type)
+    fprintf (stderr, " %0X=", g->glyph_id);
+  switch (g->positioning_type)
+    {
+    case 1: case 2:
+      {
+       int format = g->f.f1.format;
+
+       if (format & OTF_XPlacement)
+         fprintf (stderr, "X:%d", g->f.f1.value->XPlacement);
+       if (format & OTF_XPlaDevice)
+         fprintf (stderr, "+alpha");
+       if (format & OTF_YPlacement)
+         fprintf (stderr, "Y:%d", g->f.f1.value->YPlacement);
+       if (format & OTF_YPlaDevice)
+         fprintf (stderr, "+alpha");
+       if (format & OTF_XAdvance)
+         fprintf (stderr, "X+:%d", g->f.f1.value->XAdvance);
+       if (format & OTF_XAdvDevice)
+         fprintf (stderr, "+alpha");
+       break;
+      }
+    case 3:
+      print_anchor ("entry", g->f.f3.entry_anchor);
+      print_anchor ("exit", g->f.f3.entry_anchor);
+      break;
+    case 4:
+      print_anchor ("mark", g->f.f4.mark_anchor);
+      print_anchor ("base", g->f.f4.base_anchor);
+      break;
+    case 5:
+      print_anchor ("mark", g->f.f5.mark_anchor);
+      print_anchor ("lig", g->f.f5.ligature_anchor);
+      break;
+    case 6:
+      print_anchor ("mark1", g->f.f6.mark1_anchor);
+      print_anchor ("mark2", g->f.f6.mark2_anchor);
+      break;
+    }
+}
+
 static int
 lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
             OTF_GlyphString *gstring, int gidx, int accumulate)
@@ -784,8 +845,15 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
   OTF_Glyph *g = gstring->glyphs + gidx;
   int i;
 
+  if (debug_flag)
+    fprintf (stderr, "[GPOS] glyph:%04X lookup:%02d",
+            g->glyph_id, lookup_list_index);
   if (IGNORED_GLYPH (g, flag))
-    return (gidx + 1);
+    {
+      if (debug_flag)
+       fprintf (stderr, " glyph ignored\n");
+      return (gidx + 1);
+    }
 
   /* Try all subtables until one of them handles the current glyph.  */
   for (i = 0; i < lookup->SubTableCount && gidx == orig_gidx; i++)
@@ -806,6 +874,8 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
          subtable = extension1->ExtensionSubtable;
        }
 
+      if (debug_flag)
+       fprintf (stderr, "/%d", lookup_type);
       if (subtable->Coverage.offset)
        {
          coverage_idx = get_coverage_index (&subtable->Coverage,
@@ -840,6 +910,8 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
          g->positioning_type = positioning_type;
          g->f.f1.format = format;
          g->f.f1.value = value;
+         if (debug_flag)
+           print_glyph_positioning (g, 0);
          gidx++;
          break;
 
@@ -852,8 +924,7 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
                 next_gidx < gstring->used && IGNORED_GLYPH (nextg, flag);
                 next_gidx++, nextg++);
 
-           if (next_gidx >= gstring->used
-               || nextg->positioning_type)
+           if (next_gidx >= gstring->used)
              continue;
            if (subtable->Format == 1)
              {
@@ -876,6 +947,8 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
                          g->positioning_type = lookup_type;
                          g->f.f2.format = pair1->ValueFormat1;
                          g->f.f2.value = &set->PairValueRecord[j].Value1;
+                         if (debug_flag)
+                           print_glyph_positioning (g, 1);
                        }
                      gidx = next_gidx;
                      g = nextg;
@@ -889,7 +962,8 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
                          g->positioning_type = lookup_type;
                          g->f.f2.format = pair1->ValueFormat2;
                          g->f.f2.value = &set->PairValueRecord[j].Value2;
-                         gidx++;
+                         if (debug_flag)
+                           print_glyph_positioning (g, 2);
                        }
                      break;
                    }
@@ -914,6 +988,8 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
                    g->f.f2.format = pair2->ValueFormat1;
                    g->f.f2.value
                      = &pair2->Class1Record[class1].Class2Record[class2].Value1;
+                   if (debug_flag)
+                     print_glyph_positioning (g, 1);
                  }
                gidx = next_gidx;
                g = nextg;
@@ -928,7 +1004,8 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
                    g->f.f2.format = pair2->ValueFormat2;
                    g->f.f2.value
                      = &pair2->Class1Record[class1].Class2Record[class2].Value2;
-                   gidx++;
+                   if (debug_flag)
+                     print_glyph_positioning (g, 2);
                  }
              }
          }
@@ -938,16 +1015,14 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
          {
            OTF_GPOS_Cursive1 *cursive1 = &subtable->u.cursive1;
          
-           if (accumulate && g->positioning_type)
-             {
-               gidx = gstring_insert_for_gpos (gstring, gidx);
-               g = gstring->glyphs + gidx;
-             }
            g->positioning_type = lookup_type;
            g->f.f3.entry_anchor
              = &cursive1->EntryExitRecord[coverage_idx].EntryAnchor;
            g->f.f3.exit_anchor
              = &cursive1->EntryExitRecord[coverage_idx].ExitAnchor;
+           if (debug_flag)
+             print_glyph_positioning (g, 0);
+           gidx++;
          }
          break;
 
@@ -976,15 +1051,13 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
              mark_record = mark_base1->MarkArray.MarkRecord + coverage_idx;
              base_record
                = mark_base1->BaseArray.AnchorRecord + coverage_idx_base;
-             if (accumulate && g->positioning_type)
-               {
-                 gidx = gstring_insert_for_gpos (gstring, gidx);
-                 g = gstring->glyphs + gidx;
-               }
              g->f.f4.mark_anchor = &mark_record->MarkAnchor;
              g->f.f4.base_anchor
                = &base_record->Anchor[mark_record->Class];
              g->positioning_type = lookup_type;
+             if (debug_flag)
+               print_glyph_positioning (g, 0);
+             gidx++;
            }
          break;
 
@@ -1031,14 +1104,12 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
                  if (lig_anchor[mark_record->Class].AnchorFormat
                      && num_class[mark_record->Class]-- == 0)
                    {
-                     if (accumulate && g->positioning_type)
-                       {
-                         gidx = gstring_insert_for_gpos (gstring, gidx);
-                         g = gstring->glyphs + gidx;
-                       }
                      g->positioning_type = lookup_type;
                      g->f.f5.mark_anchor = &mark_record->MarkAnchor;
                      g->f.f5.ligature_anchor = lig_anchor + mark_record->Class;
+                     if (debug_flag)
+                       print_glyph_positioning (g, 0);
+                     gidx++;
                      break;
                    }
                }
@@ -1069,15 +1140,13 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
              mark1_record = mark_mark1->Mark1Array.MarkRecord + coverage_idx;
              mark2_record
                = mark_mark1->Mark2Array.AnchorRecord + coverage_idx_base;
-             if (accumulate && g->positioning_type)
-               {
-                 gidx = gstring_insert_for_gpos (gstring, gidx);
-                 g = gstring->glyphs + gidx;
-               }
              g->f.f6.mark1_anchor = &mark1_record->MarkAnchor;
              g->f.f6.mark2_anchor
                = &mark2_record->Anchor[mark1_record->Class];
              g->positioning_type = lookup_type;
+             if (debug_flag)
+               print_glyph_positioning (g, 0);
+             gidx++;
              break;
            }
          break;
@@ -1255,87 +1324,117 @@ lookup_gpos (OTF_LookupList *lookup_list, unsigned lookup_list_index,
        }
     }
   if (gidx == orig_gidx)
-    gidx++;
+    {
+      if (debug_flag)
+       fprintf (stderr, " no match\n");
+      gidx++;
+    }
+  else if (debug_flag)
+    fprintf (stderr, "\n");
   return gidx;
 }
 
-static int
-lookup_encoding_0 (OTF_EncodingSubtable0 *sub0, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_0 (int c, OTF_EncodingSubtable *sub)
 {
-  int i, c;
-
-  for (i = 0; i < gstring->used; i++)
-    {
-      c = gstring->glyphs[i].c;
-      if (c < 0 || c >= 256)
-       gstring->glyphs[i].glyph_id = 0;
-      else
-       gstring->glyphs[i].glyph_id = sub0->glyphIdArray[c];
-    }
-  return 0;
+  return ((c < 0 || c >= 256)
+         ? 0
+         : sub->f.f0->glyphIdArray[c]);
 }
 
-static int
-lookup_encoding_2 (OTF_EncodingSubtable2 *sub2, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_2 (int c, OTF_EncodingSubtable *sub)
 {
   return 0;
 }
 
-static int
-lookup_encoding_4 (OTF_EncodingSubtable4 *sub4, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_4 (int c, OTF_EncodingSubtable *sub)
 {
-  int i, j, c;
-  int segCount = sub4->segCountX2 / 2;
+  int segCount, i;
+  OTF_EncodingSubtable4 *sub4;
 
-  for (i = 0; i < gstring->used; i++)
+  if (c < 0)
+    return 0;
+  sub4 = sub->f.f4;
+  segCount = sub4->segCountX2 / 2;
+  for (i = 0; i < segCount; i++)
     {
-      c = gstring->glyphs[i].c;
-      if (c < 0)
-       gstring->glyphs[i].glyph_id = 0;
-      for (j = 0; j < segCount; j++)
-       {
-         OTF_cmapSegment *seg = sub4->segments + i;
+      OTF_cmapSegment *seg = sub4->segments + i;
 
-         if (c >= seg->startCount && c <= seg->endCount)
-           {
-             if (seg->idRangeOffset == 0xFFFF)
-               gstring->glyphs[i].glyph_id = c + seg->idDelta;
-             else
-               gstring->glyphs[i].glyph_id
-                 = sub4->glyphIdArray[seg->idRangeOffset
-                                      + (c - seg->startCount)];
-             break;
-           }
+      if (c >= seg->startCount && c <= seg->endCount)
+       {
+         if (seg->idRangeOffset == 0xFFFF)
+           return c + seg->idDelta;
+         else
+           return sub4->glyphIdArray[seg->idRangeOffset
+                                     + (c - seg->startCount)];
        }
     }
-
   return 0;
 }
 
-static int
-lookup_encoding_6 (OTF_EncodingSubtable6 *sub6, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_6 (int c, OTF_EncodingSubtable *sub)
 {
   return 0;
 }
 
-static int
-lookup_encoding_8 (OTF_EncodingSubtable8 *sub8, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_8 (int c, OTF_EncodingSubtable *sub)
 {
   return 0;
 }
 
-static int
-lookup_encoding_10 (OTF_EncodingSubtable10 *sub10, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_10 (int c, OTF_EncodingSubtable *sub)
 {
   return 0;
 }
 
-static int
-lookup_encoding_12 (OTF_EncodingSubtable12 *sub12, OTF_GlyphString *gstring)
+static unsigned
+lookup_encoding_12 (int c, OTF_EncodingSubtable *sub)
 {
+  OTF_EncodingSubtable12 *sub12;
+  OTF_cmapGroup *g, *gend;
+
+  if (c < 0)
+    return 0;
+  sub12 = sub->f.f12;
+  g = sub12->Groups;
+  gend = sub12->Groups + sub12->nGroups;
+  while (g < gend)
+    {
+      if (g->startCharCode <= c && c <= g->endCharCode)
+       return (g->startGlyphID + (c - g->startCharCode));
+      g++;
+    }
   return 0;
 }
 
+typedef unsigned (*lookup_cmap_func) (int, OTF_EncodingSubtable *);
+
+static lookup_cmap_func lookup_cmap_func_table[] =
+  {
+    lookup_encoding_0, lookup_encoding_2, lookup_encoding_4, lookup_encoding_6,
+    lookup_encoding_8, lookup_encoding_10, lookup_encoding_12
+  };
+
+static unsigned
+get_GlyphID (OTF_cmap *cmap, int c)
+{
+  OTF_EncodingSubtable *sub;
+  lookup_cmap_func lookupper;
+
+  if (c < 0x10000 && cmap->unicode_table)
+    return cmap->unicode_table[c];
+  if (cmap->table_index < 0)
+    return 0;
+  sub = &cmap->EncodingRecord[cmap->table_index].subtable;
+  lookupper = lookup_cmap_func_table[sub->format / 2];
+  return lookupper (c, sub);
+}
+
 static OTF_GlyphID
 get_uvs_glyph (OTF_cmap *cmap, OTF_EncodingSubtable14 *sub14, int c1, int c2)
 {
@@ -1371,7 +1470,7 @@ get_uvs_glyph (OTF_cmap *cmap, OTF_EncodingSubtable14 *sub14, int c1, int c2)
                  startUnicodeValue = uVRs[bottom].startUnicodeValue;
                  additionalCount = uVRs[bottom].additionalCount;
                  if (c1 <= startUnicodeValue + additionalCount)
-                   return cmap->unicode_table[c1];
+                   return get_GlyphID (cmap, c1);
                }
            }
          if (record->nonDefaultUVSOffset)
@@ -1429,6 +1528,71 @@ check_cmap_uvs (OTF_cmap *cmap, OTF_GlyphString *gstring, int idx)
 
 \f
 
+/* GDEF */
+/* Table of GlyphClass and MarkAttackClass.
+
+   For the Nth element CHAR, CHAR and the succeeding characters
+   (before CHAR of the next element) has GlyphClass C (= (N % 2) ? 3 : 1).
+
+   This table is generated from the General Category (GC) property of
+   characters defined in the Unicode Character Database.  */
+
+static int glyph_class_table[] =
+  { 0x00000, 0x00300, 0x00370, 0x00483, 0x00487, 0x00488, 0x0048A, 0x00591,
+    0x005BE, 0x005BF, 0x005C0, 0x005C1, 0x005C3, 0x005C4, 0x005C6, 0x005C7,
+    0x005C8, 0x00610, 0x00616, 0x0064B, 0x0065F, 0x00670, 0x00671, 0x006D6,
+    0x006DD, 0x006DE, 0x006E5, 0x006E7, 0x006E9, 0x006EA, 0x006EE, 0x00711,
+    0x00712, 0x00730, 0x0074B, 0x007A6, 0x007B1, 0x007EB, 0x007F4, 0x00901,
+    0x00904, 0x0093C, 0x0093D, 0x0093E, 0x0094E, 0x00951, 0x00955, 0x00962,
+    0x00964, 0x00981, 0x00984, 0x009BC, 0x009BD, 0x009BE, 0x009C5, 0x009C7,
+    0x009CE, 0x009D7, 0x009D8, 0x009E2, 0x009E4, 0x00A01, 0x00A04, 0x00A3C,
+    0x00A3D, 0x00A3E, 0x00A4E, 0x00A70, 0x00A72, 0x00A81, 0x00A84, 0x00ABC,
+    0x00ABD, 0x00ABE, 0x00ACE, 0x00AE2, 0x00AE4, 0x00B01, 0x00B04, 0x00B3C,
+    0x00B3D, 0x00B3E, 0x00B44, 0x00B47, 0x00B58, 0x00B82, 0x00B83, 0x00BBE,
+    0x00BCE, 0x00BD7, 0x00BD8, 0x00C01, 0x00C04, 0x00C3E, 0x00C45, 0x00C46,
+    0x00C57, 0x00C82, 0x00C84, 0x00CBC, 0x00CBD, 0x00CBE, 0x00CC5, 0x00CC6,
+    0x00CCE, 0x00CD5, 0x00CD7, 0x00CE2, 0x00CE4, 0x00D02, 0x00D04, 0x00D3E,
+    0x00D44, 0x00D46, 0x00D4E, 0x00D57, 0x00D58, 0x00D82, 0x00D84, 0x00DCA,
+    0x00DCB, 0x00DCF, 0x00DD7, 0x00DD8, 0x00DF4, 0x00E31, 0x00E32, 0x00E34,
+    0x00E3B, 0x00E47, 0x00E4F, 0x00EB1, 0x00EB2, 0x00EB4, 0x00EBD, 0x00EC8,
+    0x00ECE, 0x00F18, 0x00F1A, 0x00F35, 0x00F36, 0x00F37, 0x00F38, 0x00F39,
+    0x00F3A, 0x00F3E, 0x00F40, 0x00F71, 0x00F85, 0x00F86, 0x00F88, 0x00F90,
+    0x00FBD, 0x00FC6, 0x00FC7, 0x0102C, 0x0103A, 0x01056, 0x0105A, 0x0135F,
+    0x01360, 0x01712, 0x01715, 0x01732, 0x01735, 0x01752, 0x01754, 0x01772,
+    0x01774, 0x017B6, 0x017D4, 0x017DD, 0x017DE, 0x0180B, 0x0180E, 0x018A9,
+    0x018AA, 0x01920, 0x0193C, 0x019B0, 0x019C1, 0x019C8, 0x019CA, 0x01A17,
+    0x01A1C, 0x01B00, 0x01B05, 0x01B34, 0x01B45, 0x01B6B, 0x01B74, 0x01DC0,
+    0x01E00, 0x020D0, 0x020F0, 0x0302A, 0x03030, 0x03099, 0x0309B, 0x0A802,
+    0x0A803, 0x0A806, 0x0A807, 0x0A80B, 0x0A80C, 0x0A823, 0x0A828, 0x0FB1E,
+    0x0FB1F, 0x0FE00, 0x0FE10, 0x0FE20, 0x0FE24, 0x10A01, 0x10A10, 0x10A38,
+    0x10A40, 0x1D165, 0x1D16A, 0x1D16D, 0x1D173, 0x1D17B, 0x1D183, 0x1D185,
+    0x1D18C, 0x1D1AA, 0x1D1AE, 0x1D242, 0x1D245, 0xE0100, 0xE01F0 };
+
+int get_class_def_auto (int c)
+{
+  static int table_size
+    = sizeof glyph_class_table / sizeof glyph_class_table[0];
+  int low, high, mid;
+
+  if (c >= glyph_class_table[table_size - 1])
+    return 0;
+  low = 0;
+  high = table_size - 1;
+  while (1)
+    {
+      mid = (low + high) / 2;
+      if (c < glyph_class_table[mid])
+       high = mid - 1;
+      else if (c >= glyph_class_table[mid + 1])
+       low = mid + 1;
+      else
+       break;
+    }
+  return ((mid % 2) ? 3 : 1);
+}
+
+\f
+
 /* API */
 
 #define UVS_P(C)       \
@@ -1439,12 +1603,21 @@ OTF_drive_cmap (OTF *otf, OTF_GlyphString *gstring)
 {
   OTF_cmap *cmap;
   int i;
+  OTF_EncodingSubtable *sub;
+  lookup_cmap_func lookupper;
 
   if (! otf->cmap
       && OTF_get_table (otf, "cmap") < 0)
     return -1;
 
   cmap = otf->cmap;
+  if (cmap->table_index < 0)
+    lookupper = NULL;
+  else
+    {
+      sub = &cmap->EncodingRecord[cmap->table_index].subtable;
+      lookupper = lookup_cmap_func_table[sub->format / 2];
+    }
   for (i = 0; i < gstring->used; i++)
     if (! gstring->glyphs[i].glyph_id)
       {
@@ -1453,8 +1626,10 @@ OTF_drive_cmap (OTF *otf, OTF_GlyphString *gstring)
          gstring->glyphs[i].glyph_id = 0;
        else if (UVS_P (c) && i > 0)
          check_cmap_uvs (cmap, gstring, i);
-       else
+       else if (c < 0x10000)
          gstring->glyphs[i].glyph_id = cmap->unicode_table[c];
+       else if (lookupper)
+         gstring->glyphs[i].glyph_id = lookupper (c, sub);
       }
   return 0;
 }
@@ -1469,6 +1644,7 @@ OTF_drive_cmap2 (OTF *otf, OTF_GlyphString *gstring,
   char *errfmt = "CMAP Looking up%s";
   int errret = -1;
   OTF_EncodingRecord *enc;
+  lookup_cmap_func lookupper;
 
   if (! otf->cmap
       && OTF_get_table (otf, "cmap") < 0)
@@ -1482,17 +1658,23 @@ OTF_drive_cmap2 (OTF *otf, OTF_GlyphString *gstring,
   if (i == cmap->numTables)
     OTF_ERROR (OTF_ERROR_CMAP_DRIVE, " (unknown platformID/encodingID)");
   enc = cmap->EncodingRecord + i;
-  switch (enc->subtable.format)
-    {
-    case 0: return lookup_encoding_0 (enc->subtable.f.f0, gstring);
-    case 2: return lookup_encoding_2 (enc->subtable.f.f2, gstring);
-    case 4: return lookup_encoding_4 (enc->subtable.f.f4, gstring);
-    case 6: return lookup_encoding_6 (enc->subtable.f.f6, gstring);
-    case 8: return lookup_encoding_8 (enc->subtable.f.f8, gstring);
-    case 10: return lookup_encoding_10 (enc->subtable.f.f10, gstring);
-    case 12: return lookup_encoding_12 (enc->subtable.f.f12, gstring);
-    }
-  OTF_ERROR (OTF_ERROR_CMAP_DRIVE, " (invalid format)");
+  if (enc->subtable.format > 12)
+    OTF_ERROR (OTF_ERROR_CMAP_DRIVE, " (invalid format)");
+  lookupper = lookup_cmap_func_table[enc->subtable.format / 2];
+
+  for (i = 0; i < gstring->used; i++)
+    if (! gstring->glyphs[i].glyph_id)
+      {
+       int c = gstring->glyphs[i].c;
+       if (c < 32 || ! cmap->unicode_table)
+         gstring->glyphs[i].glyph_id = 0;
+       else if (UVS_P (c) && i > 0)
+         check_cmap_uvs (cmap, gstring, i);
+       else if (c < 0x10000)
+         gstring->glyphs[i].glyph_id = cmap->unicode_table[c];
+       else
+         gstring->glyphs[i].glyph_id = lookupper (c, &enc->subtable);
+      }
 }
 
 
@@ -1554,6 +1736,10 @@ OTF_drive_gdef (OTF *otf, OTF_GlyphString *gstring)
       gstring->glyphs[i].GlyphClass
        = get_class_def (&gdef->glyph_class_def,
                         gstring->glyphs[i].glyph_id);
+  else
+    for (i = 0; i < gstring->used; i++)
+      gstring->glyphs[i].GlyphClass
+       = get_class_def_auto (gstring->glyphs[i].c);
 
   if (gdef->mark_attach_class_def.offset)
     for (i = 0; i < gstring->used; i++)
@@ -1735,3 +1921,176 @@ OTF_drive_gsub_alternate (OTF *otf, OTF_GlyphString *gstring,
 {
   return OTF_drive_gsub_internal (otf, gstring, script, language, features, 1);
 }
+
+static int
+iterate_coverage (OTF *otf, const char *feature, 
+                 OTF_Feature_Callback callback,
+                 OTF_Coverage *coverage)
+{
+  int i;
+
+  if (coverage->CoverageFormat == 1)
+    {
+      for (i = 0; i < coverage->Count; i++)
+       if (callback (otf, feature, coverage->table.GlyphArray[i]) < 0)
+         return -1;
+    }
+  else
+    {
+      for (i = 0; i < coverage->Count; i++)
+       {
+         OTF_RangeRecord *range = coverage->table.RangeRecord + i;
+         unsigned id;
+         for (id = range->Start; id <= range->End; id++)
+           if (callback (otf, feature, id) < 0)
+             return -1;
+       }
+    }
+  return 0;
+}
+
+static int
+iterate_feature (OTF *otf, const char *feature,
+                OTF_Feature_Callback callback,
+                OTF_Lookup *lookup)
+{
+  int i, j, k, l;
+
+  for (i = 0; i < lookup->SubTableCount; i++)
+    {
+      unsigned lookup_type = lookup->LookupType;
+      OTF_LookupSubTableGSUB *subtable = lookup->SubTable.gsub + i;
+
+      if (lookup_type == 7)
+       {
+         OTF_GSUB_Extension1 *extension1 = &subtable->u.extension1;
+
+         lookup_type = extension1->ExtensionLookupType;
+         subtable = extension1->ExtensionSubtable;
+       }
+
+      if ((lookup_type >= 1 && lookup_type <= 3) || lookup_type == 8)
+       {
+         if (iterate_coverage (otf, feature, callback, &subtable->Coverage)
+             < 0)
+           return -1;
+       }
+      else if (lookup_type == 4)
+       {
+         OTF_GSUB_Ligature1 *lig1;
+
+         if (iterate_coverage (otf, feature, callback, &subtable->Coverage)
+             < 0)
+           return -1;
+         lig1 = &subtable->u.ligature1;
+         for (j = 0; j < lig1->LigSetCount; j++)
+           {
+             OTF_LigatureSet *ligset = lig1->LigatureSet + j;
+
+             for (k = 0; k < ligset->LigatureCount; k++)
+               {
+                 OTF_Ligature *lig = ligset->Ligature + k;
+                 for (l = 0; l < lig->CompCount - 1; l++)
+                   if (callback (otf, feature, lig->Component[l]) < 0)
+                     return -1;
+               }
+           }
+       }
+      else if (lookup_type == 6)
+       {
+         if (subtable->Format == 1)
+           {
+             OTF_GSUB_ChainContext1 *context1 = &subtable->u.chain_context1;
+             for (j = 0; j < context1->ChainRuleSetCount; j++)
+               {
+                 OTF_ChainRuleSet *set = context1->ChainRuleSet + j;
+                 for (k = 0; k < set->ChainRuleCount; k++)
+                   {
+                     OTF_ChainRule *rule = set->ChainRule + k;
+                     for (l = 0; l < rule->LookupCount; l++)
+                       {
+                         OTF_Lookup *lkup
+                           = (otf->gsub->LookupList.Lookup
+                              + rule->LookupRecord[l].LookupListIndex);
+                         if (iterate_feature (otf, feature, callback, lkup)
+                             < 0)
+                           return -1;
+                       }
+                   }
+               }
+           }
+         else if (subtable->Format == 2)
+           {
+             OTF_GSUB_ChainContext2 *context2 = &subtable->u.chain_context2;
+
+             for (j = 0; j < context2->ChainClassSetCnt; j++)
+               {
+                 OTF_ChainClassSet *set = context2->ChainClassSet + j;
+                 for (k = 0; k < set->ChainClassRuleCnt; j++)
+                   {
+                     OTF_ChainClassRule *rule = set->ChainClassRule + k;
+
+                     for (l = 0; l < rule->LookupCount; l++)
+                       {
+                         OTF_Lookup *lkup
+                           = (otf->gsub->LookupList.Lookup
+                              + rule->LookupRecord[k].LookupListIndex);
+                         if (iterate_feature (otf, feature, callback, lkup)
+                             < 0)
+                           return -1;
+                       }
+                   }
+               }
+           }
+         else
+           {
+             OTF_GSUB_ChainContext3 *context3 = &subtable->u.chain_context3;
+             for (j = 0; j < context3->LookupCount; j++)
+               {
+                 OTF_Lookup *lkup
+                   = (otf->gsub->LookupList.Lookup
+                      + context3->LookupRecord[j].LookupListIndex);
+                 if (iterate_feature (otf, feature, callback, lkup) < 0)
+                   return -1;
+               }
+           }
+       }
+    }
+  return 0;
+}
+
+int
+OTF_iterate_gsub_feature (OTF *otf, OTF_Feature_Callback callback,
+                         const char *script, const char *language,
+                         const char *feature)
+{
+  char *errfmt = "GSUB iterate feature%s";
+  int errret = -1;
+  int i;
+
+  OTF_GSUB *gsub;
+  OTF_LangSys *langsys;
+  char *lookup_flags;
+
+  if (OTF_get_table (otf, "GSUB") < 0)
+    return errret;
+  gsub = otf->gsub;
+  if (gsub->FeatureList.FeatureCount == 0
+      || gsub->LookupList.LookupCount == 0)
+    return 0;
+  langsys = get_langsys (&gsub->ScriptList, script, language);
+  if (! langsys)
+    return errret;
+  lookup_flags = alloca (gsub->LookupList.LookupCount);
+  if (! lookup_flags
+      || setup_lookup_flags (&gsub->LookupList, &gsub->FeatureList, langsys,
+                            feature, lookup_flags) < 0)
+    OTF_ERROR (OTF_ERROR_MEMORY, " feature");
+
+  for (i = 0; i < gsub->LookupList.LookupCount; i++)
+    if (lookup_flags[i])
+      if (iterate_feature (otf, feature, callback, gsub->LookupList.Lookup + i)
+         < 0)
+       return -1;
+  return 0;
+}