[reorg] Move more GPOS lookups to new directory.

src/OT/Layout/GPOS/Anchor.hh

@@ -0,0 +1,84 @@
+#ifndef OT_LAYOUT_GPOS_ANCHOR_HH
+#define OT_LAYOUT_GPOS_ANCHOR_HH
+
+#include "AnchorFormat1.hh"
+#include "AnchorFormat2.hh"
+#include "AnchorFormat3.hh"
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct Anchor
+{
+  protected:
+  union {
+  HBUINT16              format;         /* Format identifier */
+  AnchorFormat1         format1;
+  AnchorFormat2         format2;
+  AnchorFormat3         format3;
+  } u;
+  public:
+  DEFINE_SIZE_UNION (2, format);
+
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    if (!u.format.sanitize (c)) return_trace (false);
+    switch (u.format) {
+    case 1: return_trace (u.format1.sanitize (c));
+    case 2: return_trace (u.format2.sanitize (c));
+    case 3: return_trace (u.format3.sanitize (c));
+    default:return_trace (true);
+    }
+  }
+
+  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id,
+                   float *x, float *y) const
+  {
+    *x = *y = 0;
+    switch (u.format) {
+    case 1: u.format1.get_anchor (c, glyph_id, x, y); return;
+    case 2: u.format2.get_anchor (c, glyph_id, x, y); return;
+    case 3: u.format3.get_anchor (c, glyph_id, x, y); return;
+    default:                                          return;
+    }
+  }
+
+  bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    switch (u.format) {
+    case 1: return_trace (bool (reinterpret_cast<Anchor *> (u.format1.copy (c->serializer))));
+    case 2:
+      if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
+      {
+        // AnchorFormat 2 just containins extra hinting information, so
+        // if hints are being dropped convert to format 1.
+        return_trace (bool (reinterpret_cast<Anchor *> (u.format1.copy (c->serializer))));
+      }
+      return_trace (bool (reinterpret_cast<Anchor *> (u.format2.copy (c->serializer))));
+    case 3: return_trace (bool (reinterpret_cast<Anchor *> (u.format3.copy (c->serializer,
+                                                                            c->plan->layout_variation_idx_map))));
+    default:return_trace (false);
+    }
+  }
+
+  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
+  {
+    switch (u.format) {
+    case 1: case 2:
+      return;
+    case 3:
+      u.format3.collect_variation_indices (c);
+      return;
+    default: return;
+    }
+  }
+};
+
+}
+}
+}
+
+#endif  // OT_LAYOUT_GPOS_ANCHOR_HH

src/OT/Layout/GPOS/AnchorFormat1.hh

@@ -0,0 +1,46 @@
+#ifndef OT_LAYOUT_GPOS_ANCHORFORMAT1_HH
+#define OT_LAYOUT_GPOS_ANCHORFORMAT1_HH
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct AnchorFormat1
+{
+  protected:
+  HBUINT16      format;                 /* Format identifier--format = 1 */
+  FWORD         xCoordinate;            /* Horizontal value--in design units */
+  FWORD         yCoordinate;            /* Vertical value--in design units */
+  public:
+  DEFINE_SIZE_STATIC (6);
+
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (c->check_struct (this));
+  }
+
+  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id HB_UNUSED,
+                   float *x, float *y) const
+  {
+    hb_font_t *font = c->font;
+    *x = font->em_fscale_x (xCoordinate);
+    *y = font->em_fscale_y (yCoordinate);
+  }
+
+  AnchorFormat1* copy (hb_serialize_context_t *c) const
+  {
+    TRACE_SERIALIZE (this);
+    AnchorFormat1* out = c->embed<AnchorFormat1> (this);
+    if (!out) return_trace (out);
+    out->format = 1;
+    return_trace (out);
+  }
+};
+
+
+}
+}
+}
+
+#endif  // OT_LAYOUT_GPOS_ANCHORFORMAT1_HH

src/OT/Layout/GPOS/AnchorFormat2.hh

@@ -0,0 +1,58 @@
+#ifndef OT_LAYOUT_GPOS_ANCHORFORMAT2_HH
+#define OT_LAYOUT_GPOS_ANCHORFORMAT2_HH
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct AnchorFormat2
+{
+
+  protected:
+  HBUINT16      format;                 /* Format identifier--format = 2 */
+  FWORD         xCoordinate;            /* Horizontal value--in design units */
+  FWORD         yCoordinate;            /* Vertical value--in design units */
+  HBUINT16      anchorPoint;            /* Index to glyph contour point */
+  public:
+  DEFINE_SIZE_STATIC (8);
+
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (c->check_struct (this));
+  }
+
+  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id,
+                   float *x, float *y) const
+  {
+    hb_font_t *font = c->font;
+
+#ifdef HB_NO_HINTING
+    *x = font->em_fscale_x (xCoordinate);
+    *y = font->em_fscale_y (yCoordinate);
+    return;
+#endif
+
+    unsigned int x_ppem = font->x_ppem;
+    unsigned int y_ppem = font->y_ppem;
+    hb_position_t cx = 0, cy = 0;
+    bool ret;
+
+    ret = (x_ppem || y_ppem) &&
+          font->get_glyph_contour_point_for_origin (glyph_id, anchorPoint, HB_DIRECTION_LTR, &cx, &cy);
+    *x = ret && x_ppem ? cx : font->em_fscale_x (xCoordinate);
+    *y = ret && y_ppem ? cy : font->em_fscale_y (yCoordinate);
+  }
+
+  AnchorFormat2* copy (hb_serialize_context_t *c) const
+  {
+    TRACE_SERIALIZE (this);
+    return_trace (c->embed<AnchorFormat2> (this));
+  }
+};
+
+}
+}
+}
+
+#endif  // OT_LAYOUT_GPOS_ANCHORFORMAT2_HH

src/OT/Layout/GPOS/AnchorFormat3.hh

@@ -0,0 +1,70 @@
+#ifndef OT_LAYOUT_GPOS_ANCHORFORMAT3_HH
+#define OT_LAYOUT_GPOS_ANCHORFORMAT3_HH
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct AnchorFormat3
+{
+  protected:
+  HBUINT16      format;                 /* Format identifier--format = 3 */
+  FWORD         xCoordinate;            /* Horizontal value--in design units */
+  FWORD         yCoordinate;            /* Vertical value--in design units */
+  Offset16To<Device>
+                xDeviceTable;           /* Offset to Device table for X
+                                         * coordinate-- from beginning of
+                                         * Anchor table (may be NULL) */
+  Offset16To<Device>
+                yDeviceTable;           /* Offset to Device table for Y
+                                         * coordinate-- from beginning of
+                                         * Anchor table (may be NULL) */
+  public:
+  DEFINE_SIZE_STATIC (10);
+
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (c->check_struct (this) && xDeviceTable.sanitize (c, this) && yDeviceTable.sanitize (c, this));
+  }
+
+  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id HB_UNUSED,
+                   float *x, float *y) const
+  {
+    hb_font_t *font = c->font;
+    *x = font->em_fscale_x (xCoordinate);
+    *y = font->em_fscale_y (yCoordinate);
+
+    if (font->x_ppem || font->num_coords)
+      *x += (this+xDeviceTable).get_x_delta (font, c->var_store, c->var_store_cache);
+    if (font->y_ppem || font->num_coords)
+      *y += (this+yDeviceTable).get_y_delta (font, c->var_store, c->var_store_cache);
+  }
+
+  AnchorFormat3* copy (hb_serialize_context_t *c,
+                       const hb_map_t *layout_variation_idx_map) const
+  {
+    TRACE_SERIALIZE (this);
+    if (!layout_variation_idx_map) return_trace (nullptr);
+
+    auto *out = c->embed<AnchorFormat3> (this);
+    if (unlikely (!out)) return_trace (nullptr);
+
+    out->xDeviceTable.serialize_copy (c, xDeviceTable, this, 0, hb_serialize_context_t::Head, layout_variation_idx_map);
+    out->yDeviceTable.serialize_copy (c, yDeviceTable, this, 0, hb_serialize_context_t::Head, layout_variation_idx_map);
+    return_trace (out);
+  }
+
+  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
+  {
+    (this+xDeviceTable).collect_variation_indices (c->layout_variation_indices);
+    (this+yDeviceTable).collect_variation_indices (c->layout_variation_indices);
+  }
+};
+
+
+}
+}
+}
+
+#endif  // OT_LAYOUT_GPOS_ANCHORFORMAT3_HH

src/OT/Layout/GPOS/AnchorMatrix.hh

@@ -0,0 +1,77 @@
+#ifndef OT_LAYOUT_GPOS_ANCHORMATRIX_HH
+#define OT_LAYOUT_GPOS_ANCHORMATRIX_HH
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct AnchorMatrix
+{
+  HBUINT16      rows;                   /* Number of rows */
+  UnsizedArrayOf<Offset16To<Anchor>>
+                matrixZ;                /* Matrix of offsets to Anchor tables--
+                                         * from beginning of AnchorMatrix table */
+  public:
+  DEFINE_SIZE_ARRAY (2, matrixZ);
+
+  bool sanitize (hb_sanitize_context_t *c, unsigned int cols) const
+  {
+    TRACE_SANITIZE (this);
+    if (!c->check_struct (this)) return_trace (false);
+    if (unlikely (hb_unsigned_mul_overflows (rows, cols))) return_trace (false);
+    unsigned int count = rows * cols;
+    if (!c->check_array (matrixZ.arrayZ, count)) return_trace (false);
+    for (unsigned int i = 0; i < count; i++)
+      if (!matrixZ[i].sanitize (c, this)) return_trace (false);
+    return_trace (true);
+  }
+
+  const Anchor& get_anchor (unsigned int row, unsigned int col,
+                            unsigned int cols, bool *found) const
+  {
+    *found = false;
+    if (unlikely (row >= rows || col >= cols)) return Null (Anchor);
+    *found = !matrixZ[row * cols + col].is_null ();
+    return this+matrixZ[row * cols + col];
+  }
+
+  template <typename Iterator,
+            hb_requires (hb_is_iterator (Iterator))>
+  void collect_variation_indices (hb_collect_variation_indices_context_t *c,
+                                  Iterator index_iter) const
+  {
+    for (unsigned i : index_iter)
+      (this+matrixZ[i]).collect_variation_indices (c);
+  }
+
+  template <typename Iterator,
+      hb_requires (hb_is_iterator (Iterator))>
+  bool subset (hb_subset_context_t *c,
+               unsigned             num_rows,
+               Iterator             index_iter) const
+  {
+    TRACE_SUBSET (this);
+
+    auto *out = c->serializer->start_embed (this);
+
+    if (!index_iter) return_trace (false);
+    if (unlikely (!c->serializer->extend_min (out)))  return_trace (false);
+
+    out->rows = num_rows;
+    for (const unsigned i : index_iter)
+    {
+      auto *offset = c->serializer->embed (matrixZ[i]);
+      if (!offset) return_trace (false);
+      offset->serialize_subset (c, matrixZ[i], this);
+    }
+
+    return_trace (true);
+  }
+};
+
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_ANCHORMATRIX_HH */

src/OT/Layout/GPOS/Common.hh

@@ -5,12 +5,26 @@ namespace OT {
 namespace Layout {
 namespace GPOS {
 
+enum attach_type_t {
+  ATTACH_TYPE_NONE      = 0X00,
+
+  /* Each attachment should be either a mark or a cursive; can't be both. */
+  ATTACH_TYPE_MARK      = 0X01,
+  ATTACH_TYPE_CURSIVE   = 0X02,
+};
+
+/* buffer **position** var allocations */
+#define attach_chain() var.i16[0] /* glyph to which this attaches to, relative to current glyphs; negative for going back, positive for forward. */
+#define attach_type() var.u8[2] /* attachment type */
+/* Note! if attach_chain() is zero, the value of attach_type() is irrelevant. */
+
 template<typename Iterator, typename SrcLookup>
 static void SinglePos_serialize (hb_serialize_context_t *c,
                                  const SrcLookup *src,
                                  Iterator it,
                                  const hb_map_t *layout_variation_idx_map);
 
+
 }
 }
 }

src/OT/Layout/GPOS/CursivePosFormat1.hh

@@ -1,6 +1,8 @@
 #ifndef OT_LAYOUT_GPOS_CURSIVEPOSFORMAT1_HH
 #define OT_LAYOUT_GPOS_CURSIVEPOSFORMAT1_HH
 
+#include "Anchor.hh"
+
 namespace OT {
 namespace Layout {
 namespace GPOS {

src/OT/Layout/GPOS/MarkArray.hh

@@ -0,0 +1,113 @@
+#ifndef OT_LAYOUT_GPOS_MARKARRAY_HH
+#define OT_LAYOUT_GPOS_MARKARRAY_HH
+
+#include "AnchorMatrix.hh"
+#include "MarkRecord.hh"
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct MarkArray : Array16Of<MarkRecord>        /* Array of MarkRecords--in Coverage order */
+{
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (Array16Of<MarkRecord>::sanitize (c, this));
+  }
+
+  bool apply (hb_ot_apply_context_t *c,
+              unsigned int mark_index, unsigned int glyph_index,
+              const AnchorMatrix &anchors, unsigned int class_count,
+              unsigned int glyph_pos) const
+  {
+    TRACE_APPLY (this);
+    hb_buffer_t *buffer = c->buffer;
+    const MarkRecord &record = Array16Of<MarkRecord>::operator[](mark_index);
+    unsigned int mark_class = record.klass;
+
+    const Anchor& mark_anchor = this + record.markAnchor;
+    bool found;
+    const Anchor& glyph_anchor = anchors.get_anchor (glyph_index, mark_class, class_count, &found);
+    /* If this subtable doesn't have an anchor for this base and this class,
+     * return false such that the subsequent subtables have a chance at it. */
+    if (unlikely (!found)) return_trace (false);
+
+    float mark_x, mark_y, base_x, base_y;
+
+    buffer->unsafe_to_break (glyph_pos, buffer->idx + 1);
+    mark_anchor.get_anchor (c, buffer->cur().codepoint, &mark_x, &mark_y);
+    glyph_anchor.get_anchor (c, buffer->info[glyph_pos].codepoint, &base_x, &base_y);
+
+    hb_glyph_position_t &o = buffer->cur_pos();
+    o.x_offset = roundf (base_x - mark_x);
+    o.y_offset = roundf (base_y - mark_y);
+    o.attach_type() = ATTACH_TYPE_MARK;
+    o.attach_chain() = (int) glyph_pos - (int) buffer->idx;
+    buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT;
+
+    buffer->idx++;
+    return_trace (true);
+  }
+
+  template <typename Iterator,
+      hb_requires (hb_is_iterator (Iterator))>
+  bool subset (hb_subset_context_t *c,
+               Iterator             coverage,
+               const hb_map_t      *klass_mapping) const
+  {
+    TRACE_SUBSET (this);
+    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
+
+    auto* out = c->serializer->start_embed (this);
+    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
+
+    auto mark_iter =
+    + hb_zip (coverage, this->iter ())
+    | hb_filter (glyphset, hb_first)
+    | hb_map (hb_second)
+    ;
+
+    unsigned new_length = 0;
+    for (const auto& mark_record : mark_iter) {
+      if (unlikely (!mark_record.subset (c, this, klass_mapping)))
+        return_trace (false);
+      new_length++;
+    }
+
+    if (unlikely (!c->serializer->check_assign (out->len, new_length,
+                                                HB_SERIALIZE_ERROR_ARRAY_OVERFLOW)))
+      return_trace (false);
+
+    return_trace (true);
+  }
+};
+
+static void Markclass_closure_and_remap_indexes (const Coverage  &mark_coverage,
+                                                 const MarkArray &mark_array,
+                                                 const hb_set_t  &glyphset,
+                                                 hb_map_t*        klass_mapping /* INOUT */)
+{
+  hb_set_t orig_classes;
+
+  + hb_zip (mark_coverage, mark_array)
+  | hb_filter (glyphset, hb_first)
+  | hb_map (hb_second)
+  | hb_map (&MarkRecord::get_class)
+  | hb_sink (orig_classes)
+  ;
+
+  unsigned idx = 0;
+  for (auto klass : orig_classes.iter ())
+  {
+    if (klass_mapping->has (klass)) continue;
+    klass_mapping->set (klass, idx);
+    idx++;
+  }
+}
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_MARKARRAY_HH */

src/OT/Layout/GPOS/MarkBasePos.hh

@@ -0,0 +1,34 @@
+#ifndef OT_LAYOUT_GPOS_MARKBASEPOS_HH
+#define OT_LAYOUT_GPOS_MARKBASEPOS_HH
+
+#include "MarkBasePosFormat1.hh"
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct MarkBasePos
+{
+  protected:
+  union {
+  HBUINT16              format;         /* Format identifier */
+  MarkBasePosFormat1    format1;
+  } u;
+
+  template <typename context_t, typename ...Ts>
+  typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
+  {
+    TRACE_DISPATCH (this, u.format);
+    if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
+    switch (u.format) {
+    case 1: return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
+    default:return_trace (c->default_return_value ());
+    }
+  }
+};
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_MARKBASEPOS_HH */

src/OT/Layout/GPOS/MarkBasePosFormat1.hh

@@ -0,0 +1,217 @@
+#ifndef OT_LAYOUT_GPOS_MARKBASEPOSFORMAT1_HH
+#define OT_LAYOUT_GPOS_MARKBASEPOSFORMAT1_HH
+
+#include "MarkArray.hh"
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+typedef AnchorMatrix BaseArray;         /* base-major--
+                                         * in order of BaseCoverage Index--,
+                                         * mark-minor--
+                                         * ordered by class--zero-based. */
+
+struct MarkBasePosFormat1
+{
+  protected:
+  HBUINT16      format;                 /* Format identifier--format = 1 */
+  Offset16To<Coverage>
+                markCoverage;           /* Offset to MarkCoverage table--from
+                                         * beginning of MarkBasePos subtable */
+  Offset16To<Coverage>
+                baseCoverage;           /* Offset to BaseCoverage table--from
+                                         * beginning of MarkBasePos subtable */
+  HBUINT16      classCount;             /* Number of classes defined for marks */
+  Offset16To<MarkArray>
+                markArray;              /* Offset to MarkArray table--from
+                                         * beginning of MarkBasePos subtable */
+  Offset16To<BaseArray>
+                baseArray;              /* Offset to BaseArray table--from
+                                         * beginning of MarkBasePos subtable */
+
+  public:
+  DEFINE_SIZE_STATIC (12);
+
+    bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (c->check_struct (this) &&
+                  markCoverage.sanitize (c, this) &&
+                  baseCoverage.sanitize (c, this) &&
+                  markArray.sanitize (c, this) &&
+                  baseArray.sanitize (c, this, (unsigned int) classCount));
+  }
+
+  bool intersects (const hb_set_t *glyphs) const
+  {
+    return (this+markCoverage).intersects (glyphs) &&
+           (this+baseCoverage).intersects (glyphs);
+  }
+
+  void closure_lookups (hb_closure_lookups_context_t *c) const {}
+
+  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
+  {
+    + hb_zip (this+markCoverage, this+markArray)
+    | hb_filter (c->glyph_set, hb_first)
+    | hb_map (hb_second)
+    | hb_apply ([&] (const MarkRecord& record) { record.collect_variation_indices (c, &(this+markArray)); })
+    ;
+
+    hb_map_t klass_mapping;
+    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, *c->glyph_set, &klass_mapping);
+
+    unsigned basecount = (this+baseArray).rows;
+    auto base_iter =
+    + hb_zip (this+baseCoverage, hb_range (basecount))
+    | hb_filter (c->glyph_set, hb_first)
+    | hb_map (hb_second)
+    ;
+
+    hb_sorted_vector_t<unsigned> base_indexes;
+    for (const unsigned row : base_iter)
+    {
+      + hb_range ((unsigned) classCount)
+      | hb_filter (klass_mapping)
+      | hb_map ([&] (const unsigned col) { return row * (unsigned) classCount + col; })
+      | hb_sink (base_indexes)
+      ;
+    }
+    (this+baseArray).collect_variation_indices (c, base_indexes.iter ());
+  }
+
+  void collect_glyphs (hb_collect_glyphs_context_t *c) const
+  {
+    if (unlikely (!(this+markCoverage).collect_coverage (c->input))) return;
+    if (unlikely (!(this+baseCoverage).collect_coverage (c->input))) return;
+  }
+
+  const Coverage &get_coverage () const { return this+markCoverage; }
+
+  bool apply (hb_ot_apply_context_t *c) const
+  {
+    TRACE_APPLY (this);
+    hb_buffer_t *buffer = c->buffer;
+    unsigned int mark_index = (this+markCoverage).get_coverage  (buffer->cur().codepoint);
+    if (likely (mark_index == NOT_COVERED)) return_trace (false);
+
+    /* Now we search backwards for a non-mark glyph */
+    hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input;
+    skippy_iter.reset (buffer->idx, 1);
+    skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks);
+    do {
+      unsigned unsafe_from;
+      if (!skippy_iter.prev (&unsafe_from))
+      {
+        buffer->unsafe_to_concat_from_outbuffer (unsafe_from, buffer->idx + 1);
+        return_trace (false);
+      }
+
+      /* We only want to attach to the first of a MultipleSubst sequence.
+       * https://github.com/harfbuzz/harfbuzz/issues/740
+       * Reject others...
+       * ...but stop if we find a mark in the MultipleSubst sequence:
+       * https://github.com/harfbuzz/harfbuzz/issues/1020 */
+      if (!_hb_glyph_info_multiplied (&buffer->info[skippy_iter.idx]) ||
+          0 == _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]) ||
+          (skippy_iter.idx == 0 ||
+           _hb_glyph_info_is_mark (&buffer->info[skippy_iter.idx - 1]) ||
+           _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx]) !=
+           _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx - 1]) ||
+           _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]) !=
+           _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx - 1]) + 1
+           ))
+        break;
+      skippy_iter.reject ();
+    } while (true);
+
+    /* Checking that matched glyph is actually a base glyph by GDEF is too strong; disabled */
+    //if (!_hb_glyph_info_is_base_glyph (&buffer->info[skippy_iter.idx])) { return_trace (false); }
+
+    unsigned int base_index = (this+baseCoverage).get_coverage  (buffer->info[skippy_iter.idx].codepoint);
+    if (base_index == NOT_COVERED)
+    {
+      buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
+      return_trace (false);
+    }
+
+    return_trace ((this+markArray).apply (c, mark_index, base_index, this+baseArray, classCount, skippy_iter.idx));
+  }
+
+  bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
+    const hb_map_t &glyph_map = *c->plan->glyph_map;
+
+    auto *out = c->serializer->start_embed (*this);
+    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
+    out->format = format;
+
+    hb_map_t klass_mapping;
+    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, glyphset, &klass_mapping);
+
+    if (!klass_mapping.get_population ()) return_trace (false);
+    out->classCount = klass_mapping.get_population ();
+
+    auto mark_iter =
+    + hb_zip (this+markCoverage, this+markArray)
+    | hb_filter (glyphset, hb_first)
+    ;
+
+    hb_sorted_vector_t<hb_codepoint_t> new_coverage;
+    + mark_iter
+    | hb_map (hb_first)
+    | hb_map (glyph_map)
+    | hb_sink (new_coverage)
+    ;
+
+    if (!out->markCoverage.serialize_serialize (c->serializer, new_coverage.iter ()))
+      return_trace (false);
+
+    out->markArray.serialize_subset (c, markArray, this,
+                                     (this+markCoverage).iter (),
+                                     &klass_mapping);
+
+    unsigned basecount = (this+baseArray).rows;
+    auto base_iter =
+    + hb_zip (this+baseCoverage, hb_range (basecount))
+    | hb_filter (glyphset, hb_first)
+    ;
+
+    new_coverage.reset ();
+    + base_iter
+    | hb_map (hb_first)
+    | hb_map (glyph_map)
+    | hb_sink (new_coverage)
+    ;
+
+    if (!out->baseCoverage.serialize_serialize (c->serializer, new_coverage.iter ()))
+      return_trace (false);
+
+    hb_sorted_vector_t<unsigned> base_indexes;
+    for (const unsigned row : + base_iter
+                              | hb_map (hb_second))
+    {
+      + hb_range ((unsigned) classCount)
+      | hb_filter (klass_mapping)
+      | hb_map ([&] (const unsigned col) { return row * (unsigned) classCount + col; })
+      | hb_sink (base_indexes)
+      ;
+    }
+
+    out->baseArray.serialize_subset (c, baseArray, this,
+                                     base_iter.len (),
+                                     base_indexes.iter ());
+
+    return_trace (true);
+  }
+};
+
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_MARKBASEPOSFORMAT1_HH */

src/OT/Layout/GPOS/MarkLigPos.hh

@@ -0,0 +1,34 @@
+#ifndef OT_LAYOUT_GPOS_MARKLIGPOS_HH
+#define OT_LAYOUT_GPOS_MARKLIGPOS_HH
+
+#include "MarkLigPosFormat1.hh"
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct MarkLigPos
+{
+  protected:
+  union {
+  HBUINT16              format;         /* Format identifier */
+  MarkLigPosFormat1     format1;
+  } u;
+
+  template <typename context_t, typename ...Ts>
+  typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
+  {
+    TRACE_DISPATCH (this, u.format);
+    if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
+    switch (u.format) {
+    case 1: return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
+    default:return_trace (c->default_return_value ());
+    }
+  }
+};
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_MARKLIGPOS_HH */

src/OT/Layout/GPOS/MarkLigPosFormat1.hh

@@ -0,0 +1,244 @@
+#ifndef OT_LAYOUT_GPOS_MARKLIGPOSFORMAT1_HH
+#define OT_LAYOUT_GPOS_MARKLIGPOSFORMAT1_HH
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+typedef AnchorMatrix LigatureAttach;    /* component-major--
+                                         * in order of writing direction--,
+                                         * mark-minor--
+                                         * ordered by class--zero-based. */
+
+/* Array of LigatureAttach tables ordered by LigatureCoverage Index */
+struct LigatureArray : List16OfOffset16To<LigatureAttach>
+{
+  template <typename Iterator,
+            hb_requires (hb_is_iterator (Iterator))>
+  bool subset (hb_subset_context_t *c,
+               Iterator             coverage,
+               unsigned             class_count,
+               const hb_map_t      *klass_mapping) const
+  {
+    TRACE_SUBSET (this);
+    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
+
+    auto *out = c->serializer->start_embed (this);
+    if (unlikely (!c->serializer->extend_min (out)))  return_trace (false);
+
+    for (const auto _ : + hb_zip (coverage, *this)
+                  | hb_filter (glyphset, hb_first))
+    {
+      auto *matrix = out->serialize_append (c->serializer);
+      if (unlikely (!matrix)) return_trace (false);
+
+      const LigatureAttach& src = (this + _.second);
+      auto indexes =
+          + hb_range (src.rows * class_count)
+          | hb_filter ([=] (unsigned index) { return klass_mapping->has (index % class_count); })
+          ;
+      matrix->serialize_subset (c,
+                                _.second,
+                                this,
+                                src.rows,
+                                indexes);
+    }
+    return_trace (this->len);
+  }
+};
+
+struct MarkLigPosFormat1
+{
+  protected:
+  HBUINT16      format;                 /* Format identifier--format = 1 */
+  Offset16To<Coverage>
+                markCoverage;           /* Offset to Mark Coverage table--from
+                                         * beginning of MarkLigPos subtable */
+  Offset16To<Coverage>
+                ligatureCoverage;       /* Offset to Ligature Coverage
+                                         * table--from beginning of MarkLigPos
+                                         * subtable */
+  HBUINT16      classCount;             /* Number of defined mark classes */
+  Offset16To<MarkArray>
+                markArray;              /* Offset to MarkArray table--from
+                                         * beginning of MarkLigPos subtable */
+  Offset16To<LigatureArray>
+                ligatureArray;          /* Offset to LigatureArray table--from
+                                         * beginning of MarkLigPos subtable */
+  public:
+  DEFINE_SIZE_STATIC (12);
+
+  bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (c->check_struct (this) &&
+                  markCoverage.sanitize (c, this) &&
+                  ligatureCoverage.sanitize (c, this) &&
+                  markArray.sanitize (c, this) &&
+                  ligatureArray.sanitize (c, this, (unsigned int) classCount));
+  }
+
+  bool intersects (const hb_set_t *glyphs) const
+  {
+    return (this+markCoverage).intersects (glyphs) &&
+           (this+ligatureCoverage).intersects (glyphs);
+  }
+
+  void closure_lookups (hb_closure_lookups_context_t *c) const {}
+
+  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
+  {
+    + hb_zip (this+markCoverage, this+markArray)
+    | hb_filter (c->glyph_set, hb_first)
+    | hb_map (hb_second)
+    | hb_apply ([&] (const MarkRecord& record) { record.collect_variation_indices (c, &(this+markArray)); })
+    ;
+
+    hb_map_t klass_mapping;
+    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, *c->glyph_set, &klass_mapping);
+
+    unsigned ligcount = (this+ligatureArray).len;
+    auto lig_iter =
+    + hb_zip (this+ligatureCoverage, hb_range (ligcount))
+    | hb_filter (c->glyph_set, hb_first)
+    | hb_map (hb_second)
+    ;
+
+    const LigatureArray& lig_array = this+ligatureArray;
+    for (const unsigned i : lig_iter)
+    {
+      hb_sorted_vector_t<unsigned> lig_indexes;
+      unsigned row_count = lig_array[i].rows;
+      for (unsigned row : + hb_range (row_count))
+      {
+        + hb_range ((unsigned) classCount)
+        | hb_filter (klass_mapping)
+        | hb_map ([&] (const unsigned col) { return row * (unsigned) classCount + col; })
+        | hb_sink (lig_indexes)
+        ;
+      }
+
+      lig_array[i].collect_variation_indices (c, lig_indexes.iter ());
+    }
+  }
+
+  void collect_glyphs (hb_collect_glyphs_context_t *c) const
+  {
+    if (unlikely (!(this+markCoverage).collect_coverage (c->input))) return;
+    if (unlikely (!(this+ligatureCoverage).collect_coverage (c->input))) return;
+  }
+
+  const Coverage &get_coverage () const { return this+markCoverage; }
+
+  bool apply (hb_ot_apply_context_t *c) const
+  {
+    TRACE_APPLY (this);
+    hb_buffer_t *buffer = c->buffer;
+    unsigned int mark_index = (this+markCoverage).get_coverage  (buffer->cur().codepoint);
+    if (likely (mark_index == NOT_COVERED)) return_trace (false);
+
+    /* Now we search backwards for a non-mark glyph */
+    hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input;
+    skippy_iter.reset (buffer->idx, 1);
+    skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks);
+    unsigned unsafe_from;
+    if (!skippy_iter.prev (&unsafe_from))
+    {
+      buffer->unsafe_to_concat_from_outbuffer (unsafe_from, buffer->idx + 1);
+      return_trace (false);
+    }
+
+    /* Checking that matched glyph is actually a ligature by GDEF is too strong; disabled */
+    //if (!_hb_glyph_info_is_ligature (&buffer->info[skippy_iter.idx])) { return_trace (false); }
+
+    unsigned int j = skippy_iter.idx;
+    unsigned int lig_index = (this+ligatureCoverage).get_coverage  (buffer->info[j].codepoint);
+    if (lig_index == NOT_COVERED)
+    {
+      buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
+      return_trace (false);
+    }
+
+    const LigatureArray& lig_array = this+ligatureArray;
+    const LigatureAttach& lig_attach = lig_array[lig_index];
+
+    /* Find component to attach to */
+    unsigned int comp_count = lig_attach.rows;
+    if (unlikely (!comp_count))
+    {
+      buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
+      return_trace (false);
+    }
+
+    /* We must now check whether the ligature ID of the current mark glyph
+     * is identical to the ligature ID of the found ligature.  If yes, we
+     * can directly use the component index.  If not, we attach the mark
+     * glyph to the last component of the ligature. */
+    unsigned int comp_index;
+    unsigned int lig_id = _hb_glyph_info_get_lig_id (&buffer->info[j]);
+    unsigned int mark_id = _hb_glyph_info_get_lig_id (&buffer->cur());
+    unsigned int mark_comp = _hb_glyph_info_get_lig_comp (&buffer->cur());
+    if (lig_id && lig_id == mark_id && mark_comp > 0)
+      comp_index = hb_min (comp_count, _hb_glyph_info_get_lig_comp (&buffer->cur())) - 1;
+    else
+      comp_index = comp_count - 1;
+
+    return_trace ((this+markArray).apply (c, mark_index, comp_index, lig_attach, classCount, j));
+  }
+
+  bool subset (hb_subset_context_t *c) const
+  {
+    TRACE_SUBSET (this);
+    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
+    const hb_map_t &glyph_map = *c->plan->glyph_map;
+
+    auto *out = c->serializer->start_embed (*this);
+    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
+    out->format = format;
+
+    hb_map_t klass_mapping;
+    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, glyphset, &klass_mapping);
+
+    if (!klass_mapping.get_population ()) return_trace (false);
+    out->classCount = klass_mapping.get_population ();
+
+    auto mark_iter =
+    + hb_zip (this+markCoverage, this+markArray)
+    | hb_filter (glyphset, hb_first)
+    ;
+
+    auto new_mark_coverage =
+    + mark_iter
+    | hb_map_retains_sorting (hb_first)
+    | hb_map_retains_sorting (glyph_map)
+    ;
+
+    if (!out->markCoverage.serialize_serialize (c->serializer, new_mark_coverage))
+      return_trace (false);
+
+    out->markArray.serialize_subset (c, markArray, this,
+                                     (this+markCoverage).iter (),
+                                     &klass_mapping);
+
+    auto new_ligature_coverage =
+    + hb_iter (this + ligatureCoverage)
+    | hb_filter (glyphset)
+    | hb_map_retains_sorting (glyph_map)
+    ;
+
+    if (!out->ligatureCoverage.serialize_serialize (c->serializer, new_ligature_coverage))
+      return_trace (false);
+
+    out->ligatureArray.serialize_subset (c, ligatureArray, this,
+                                         hb_iter (this+ligatureCoverage), classCount, &klass_mapping);
+
+    return_trace (true);
+  }
+
+};
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_MARKLIGPOSFORMAT1_HH */

src/OT/Layout/GPOS/MarkRecord.hh

@@ -0,0 +1,52 @@
+#ifndef OT_LAYOUT_GPOS_MARKRECORD_HH
+#define OT_LAYOUT_GPOS_MARKRECORD_HH
+
+namespace OT {
+namespace Layout {
+namespace GPOS {
+
+struct MarkRecord
+{
+  friend struct MarkArray;
+
+  protected:
+  HBUINT16      klass;                  /* Class defined for this mark */
+  Offset16To<Anchor>
+                markAnchor;             /* Offset to Anchor table--from
+                                         * beginning of MarkArray table */
+  public:
+  DEFINE_SIZE_STATIC (4);
+
+  unsigned get_class () const { return (unsigned) klass; }
+  bool sanitize (hb_sanitize_context_t *c, const void *base) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (c->check_struct (this) && markAnchor.sanitize (c, base));
+  }
+
+  MarkRecord *subset (hb_subset_context_t    *c,
+                      const void             *src_base,
+                      const hb_map_t         *klass_mapping) const
+  {
+    TRACE_SUBSET (this);
+    auto *out = c->serializer->embed (this);
+    if (unlikely (!out)) return_trace (nullptr);
+
+    out->klass = klass_mapping->get (klass);
+    out->markAnchor.serialize_subset (c, markAnchor, src_base);
+    return_trace (out);
+  }
+
+  void collect_variation_indices (hb_collect_variation_indices_context_t *c,
+                                  const void *src_base) const
+  {
+    (src_base+markAnchor).collect_variation_indices (c);
+  }
+};
+
+
+}
+}
+}
+
+#endif /* OT_LAYOUT_GPOS_MARKRECORD_HH */

src/OT/Layout/GPOS/PosLookupSubTable.hh

@@ -4,6 +4,8 @@
 #include "SinglePos.hh"
 #include "PairPos.hh"
 #include "CursivePos.hh"
+#include "MarkBasePos.hh"
+#include "MarkLigPos.hh"
 
 namespace OT {
 namespace Layout {

src/hb-ot-layout-gpos-table.hh

@@ -39,633 +39,15 @@ static void Markclass_closure_and_remap_indexes (const Coverage  &mark_coverage,
 						 const hb_set_t  &glyphset,
 						 hb_map_t*        klass_mapping /* INOUT */);
 
-/* buffer **position** var allocations */
-#define attach_chain() var.i16[0] /* glyph to which this attaches to, relative to current glyphs; negative for going back, positive for forward. */
-#define attach_type() var.u8[2] /* attachment type */
-/* Note! if attach_chain() is zero, the value of attach_type() is irrelevant. */
-
-enum attach_type_t {
-  ATTACH_TYPE_NONE	= 0X00,
-
-  /* Each attachment should be either a mark or a cursive; can't be both. */
-  ATTACH_TYPE_MARK	= 0X01,
-  ATTACH_TYPE_CURSIVE	= 0X02,
-};
-
 
 /* Shared Tables: ValueRecord, Anchor Table, and MarkArray */
 
-struct AnchorFormat1
-{
-  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id HB_UNUSED,
-		   float *x, float *y) const
-  {
-    hb_font_t *font = c->font;
-    *x = font->em_fscale_x (xCoordinate);
-    *y = font->em_fscale_y (yCoordinate);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (c->check_struct (this));
-  }
-
-  AnchorFormat1* copy (hb_serialize_context_t *c) const
-  {
-    TRACE_SERIALIZE (this);
-    AnchorFormat1* out = c->embed<AnchorFormat1> (this);
-    if (!out) return_trace (out);
-    out->format = 1;
-    return_trace (out);
-  }
-
-  protected:
-  HBUINT16	format;			/* Format identifier--format = 1 */
-  FWORD		xCoordinate;		/* Horizontal value--in design units */
-  FWORD		yCoordinate;		/* Vertical value--in design units */
-  public:
-  DEFINE_SIZE_STATIC (6);
-};
-
-struct AnchorFormat2
-{
-  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id,
-		   float *x, float *y) const
-  {
-    hb_font_t *font = c->font;
-
-#ifdef HB_NO_HINTING
-    *x = font->em_fscale_x (xCoordinate);
-    *y = font->em_fscale_y (yCoordinate);
-    return;
-#endif
-
-    unsigned int x_ppem = font->x_ppem;
-    unsigned int y_ppem = font->y_ppem;
-    hb_position_t cx = 0, cy = 0;
-    bool ret;
-
-    ret = (x_ppem || y_ppem) &&
-	  font->get_glyph_contour_point_for_origin (glyph_id, anchorPoint, HB_DIRECTION_LTR, &cx, &cy);
-    *x = ret && x_ppem ? cx : font->em_fscale_x (xCoordinate);
-    *y = ret && y_ppem ? cy : font->em_fscale_y (yCoordinate);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (c->check_struct (this));
-  }
-
-  AnchorFormat2* copy (hb_serialize_context_t *c) const
-  {
-    TRACE_SERIALIZE (this);
-    return_trace (c->embed<AnchorFormat2> (this));
-  }
-
-  protected:
-  HBUINT16	format;			/* Format identifier--format = 2 */
-  FWORD		xCoordinate;		/* Horizontal value--in design units */
-  FWORD		yCoordinate;		/* Vertical value--in design units */
-  HBUINT16	anchorPoint;		/* Index to glyph contour point */
-  public:
-  DEFINE_SIZE_STATIC (8);
-};
-
-struct AnchorFormat3
-{
-  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id HB_UNUSED,
-		   float *x, float *y) const
-  {
-    hb_font_t *font = c->font;
-    *x = font->em_fscale_x (xCoordinate);
-    *y = font->em_fscale_y (yCoordinate);
-
-    if (font->x_ppem || font->num_coords)
-      *x += (this+xDeviceTable).get_x_delta (font, c->var_store, c->var_store_cache);
-    if (font->y_ppem || font->num_coords)
-      *y += (this+yDeviceTable).get_y_delta (font, c->var_store, c->var_store_cache);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (c->check_struct (this) && xDeviceTable.sanitize (c, this) && yDeviceTable.sanitize (c, this));
-  }
-
-  AnchorFormat3* copy (hb_serialize_context_t *c,
-		       const hb_map_t *layout_variation_idx_map) const
-  {
-    TRACE_SERIALIZE (this);
-    if (!layout_variation_idx_map) return_trace (nullptr);
-
-    auto *out = c->embed<AnchorFormat3> (this);
-    if (unlikely (!out)) return_trace (nullptr);
-
-    out->xDeviceTable.serialize_copy (c, xDeviceTable, this, 0, hb_serialize_context_t::Head, layout_variation_idx_map);
-    out->yDeviceTable.serialize_copy (c, yDeviceTable, this, 0, hb_serialize_context_t::Head, layout_variation_idx_map);
-    return_trace (out);
-  }
-
-  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
-  {
-    (this+xDeviceTable).collect_variation_indices (c->layout_variation_indices);
-    (this+yDeviceTable).collect_variation_indices (c->layout_variation_indices);
-  }
-
-  protected:
-  HBUINT16	format;			/* Format identifier--format = 3 */
-  FWORD		xCoordinate;		/* Horizontal value--in design units */
-  FWORD		yCoordinate;		/* Vertical value--in design units */
-  Offset16To<Device>
-		xDeviceTable;		/* Offset to Device table for X
-					 * coordinate-- from beginning of
-					 * Anchor table (may be NULL) */
-  Offset16To<Device>
-		yDeviceTable;		/* Offset to Device table for Y
-					 * coordinate-- from beginning of
-					 * Anchor table (may be NULL) */
-  public:
-  DEFINE_SIZE_STATIC (10);
-};
-
-struct Anchor
-{
-  void get_anchor (hb_ot_apply_context_t *c, hb_codepoint_t glyph_id,
-		   float *x, float *y) const
-  {
-    *x = *y = 0;
-    switch (u.format) {
-    case 1: u.format1.get_anchor (c, glyph_id, x, y); return;
-    case 2: u.format2.get_anchor (c, glyph_id, x, y); return;
-    case 3: u.format3.get_anchor (c, glyph_id, x, y); return;
-    default:					      return;
-    }
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    if (!u.format.sanitize (c)) return_trace (false);
-    switch (u.format) {
-    case 1: return_trace (u.format1.sanitize (c));
-    case 2: return_trace (u.format2.sanitize (c));
-    case 3: return_trace (u.format3.sanitize (c));
-    default:return_trace (true);
-    }
-  }
-
-  bool subset (hb_subset_context_t *c) const
-  {
-    TRACE_SUBSET (this);
-    switch (u.format) {
-    case 1: return_trace (bool (reinterpret_cast<Anchor *> (u.format1.copy (c->serializer))));
-    case 2:
-      if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
-      {
-        // AnchorFormat 2 just containins extra hinting information, so
-        // if hints are being dropped convert to format 1.
-        return_trace (bool (reinterpret_cast<Anchor *> (u.format1.copy (c->serializer))));
-      }
-      return_trace (bool (reinterpret_cast<Anchor *> (u.format2.copy (c->serializer))));
-    case 3: return_trace (bool (reinterpret_cast<Anchor *> (u.format3.copy (c->serializer,
-                                                                            c->plan->layout_variation_idx_map))));
-    default:return_trace (false);
-    }
-  }
-
-  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
-  {
-    switch (u.format) {
-    case 1: case 2:
-      return;
-    case 3:
-      u.format3.collect_variation_indices (c);
-      return;
-    default: return;
-    }
-  }
-
-  protected:
-  union {
-  HBUINT16		format;		/* Format identifier */
-  AnchorFormat1		format1;
-  AnchorFormat2		format2;
-  AnchorFormat3		format3;
-  } u;
-  public:
-  DEFINE_SIZE_UNION (2, format);
-};
-
-
-struct AnchorMatrix
-{
-  const Anchor& get_anchor (unsigned int row, unsigned int col,
-			    unsigned int cols, bool *found) const
-  {
-    *found = false;
-    if (unlikely (row >= rows || col >= cols)) return Null (Anchor);
-    *found = !matrixZ[row * cols + col].is_null ();
-    return this+matrixZ[row * cols + col];
-  }
-
-  template <typename Iterator,
-	    hb_requires (hb_is_iterator (Iterator))>
-  void collect_variation_indices (hb_collect_variation_indices_context_t *c,
-				  Iterator index_iter) const
-  {
-    for (unsigned i : index_iter)
-      (this+matrixZ[i]).collect_variation_indices (c);
-  }
-
-  template <typename Iterator,
-      hb_requires (hb_is_iterator (Iterator))>
-  bool subset (hb_subset_context_t *c,
-               unsigned             num_rows,
-               Iterator             index_iter) const
-  {
-    TRACE_SUBSET (this);
-
-    auto *out = c->serializer->start_embed (this);
-
-    if (!index_iter) return_trace (false);
-    if (unlikely (!c->serializer->extend_min (out)))  return_trace (false);
-
-    out->rows = num_rows;
-    for (const unsigned i : index_iter)
-    {
-      auto *offset = c->serializer->embed (matrixZ[i]);
-      if (!offset) return_trace (false);
-      offset->serialize_subset (c, matrixZ[i], this);
-    }
-
-    return_trace (true);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c, unsigned int cols) const
-  {
-    TRACE_SANITIZE (this);
-    if (!c->check_struct (this)) return_trace (false);
-    if (unlikely (hb_unsigned_mul_overflows (rows, cols))) return_trace (false);
-    unsigned int count = rows * cols;
-    if (!c->check_array (matrixZ.arrayZ, count)) return_trace (false);
-    for (unsigned int i = 0; i < count; i++)
-      if (!matrixZ[i].sanitize (c, this)) return_trace (false);
-    return_trace (true);
-  }
-
-  HBUINT16	rows;			/* Number of rows */
-  UnsizedArrayOf<Offset16To<Anchor>>
-		matrixZ;		/* Matrix of offsets to Anchor tables--
-					 * from beginning of AnchorMatrix table */
-  public:
-  DEFINE_SIZE_ARRAY (2, matrixZ);
-};
-
-
-struct MarkRecord
-{
-  friend struct MarkArray;
-
-  unsigned get_class () const { return (unsigned) klass; }
-  bool sanitize (hb_sanitize_context_t *c, const void *base) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (c->check_struct (this) && markAnchor.sanitize (c, base));
-  }
-
-  MarkRecord *subset (hb_subset_context_t    *c,
-                      const void             *src_base,
-                      const hb_map_t         *klass_mapping) const
-  {
-    TRACE_SUBSET (this);
-    auto *out = c->serializer->embed (this);
-    if (unlikely (!out)) return_trace (nullptr);
-
-    out->klass = klass_mapping->get (klass);
-    out->markAnchor.serialize_subset (c, markAnchor, src_base);
-    return_trace (out);
-  }
-
-  void collect_variation_indices (hb_collect_variation_indices_context_t *c,
-				  const void *src_base) const
-  {
-    (src_base+markAnchor).collect_variation_indices (c);
-  }
-
-  protected:
-  HBUINT16	klass;			/* Class defined for this mark */
-  Offset16To<Anchor>
-		markAnchor;		/* Offset to Anchor table--from
-					 * beginning of MarkArray table */
-  public:
-  DEFINE_SIZE_STATIC (4);
-};
-
-struct MarkArray : Array16Of<MarkRecord>	/* Array of MarkRecords--in Coverage order */
-{
-  bool apply (hb_ot_apply_context_t *c,
-	      unsigned int mark_index, unsigned int glyph_index,
-	      const AnchorMatrix &anchors, unsigned int class_count,
-	      unsigned int glyph_pos) const
-  {
-    TRACE_APPLY (this);
-    hb_buffer_t *buffer = c->buffer;
-    const MarkRecord &record = Array16Of<MarkRecord>::operator[](mark_index);
-    unsigned int mark_class = record.klass;
-
-    const Anchor& mark_anchor = this + record.markAnchor;
-    bool found;
-    const Anchor& glyph_anchor = anchors.get_anchor (glyph_index, mark_class, class_count, &found);
-    /* If this subtable doesn't have an anchor for this base and this class,
-     * return false such that the subsequent subtables have a chance at it. */
-    if (unlikely (!found)) return_trace (false);
-
-    float mark_x, mark_y, base_x, base_y;
-
-    buffer->unsafe_to_break (glyph_pos, buffer->idx + 1);
-    mark_anchor.get_anchor (c, buffer->cur().codepoint, &mark_x, &mark_y);
-    glyph_anchor.get_anchor (c, buffer->info[glyph_pos].codepoint, &base_x, &base_y);
-
-    hb_glyph_position_t &o = buffer->cur_pos();
-    o.x_offset = roundf (base_x - mark_x);
-    o.y_offset = roundf (base_y - mark_y);
-    o.attach_type() = ATTACH_TYPE_MARK;
-    o.attach_chain() = (int) glyph_pos - (int) buffer->idx;
-    buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT;
-
-    buffer->idx++;
-    return_trace (true);
-  }
-
-  template <typename Iterator,
-      hb_requires (hb_is_iterator (Iterator))>
-  bool subset (hb_subset_context_t *c,
-               Iterator		    coverage,
-               const hb_map_t      *klass_mapping) const
-  {
-    TRACE_SUBSET (this);
-    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
-
-    auto* out = c->serializer->start_embed (this);
-    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
-
-    auto mark_iter =
-    + hb_zip (coverage, this->iter ())
-    | hb_filter (glyphset, hb_first)
-    | hb_map (hb_second)
-    ;
-
-    unsigned new_length = 0;
-    for (const auto& mark_record : mark_iter) {
-      if (unlikely (!mark_record.subset (c, this, klass_mapping)))
-        return_trace (false);
-      new_length++;
-    }
-
-    if (unlikely (!c->serializer->check_assign (out->len, new_length,
-                                                HB_SERIALIZE_ERROR_ARRAY_OVERFLOW)))
-      return_trace (false);
-
-    return_trace (true);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (Array16Of<MarkRecord>::sanitize (c, this));
-  }
-};
 
 
 /* Lookups */
 
-typedef AnchorMatrix BaseArray;		/* base-major--
-					 * in order of BaseCoverage Index--,
-					 * mark-minor--
-					 * ordered by class--zero-based. */
 
-static void Markclass_closure_and_remap_indexes (const Coverage  &mark_coverage,
+struct MarkMarkPos
-						 const MarkArray &mark_array,
-						 const hb_set_t  &glyphset,
-						 hb_map_t*        klass_mapping /* INOUT */)
-{
-  hb_set_t orig_classes;
-
-  + hb_zip (mark_coverage, mark_array)
-  | hb_filter (glyphset, hb_first)
-  | hb_map (hb_second)
-  | hb_map (&MarkRecord::get_class)
-  | hb_sink (orig_classes)
-  ;
-
-  unsigned idx = 0;
-  for (auto klass : orig_classes.iter ())
-  {
-    if (klass_mapping->has (klass)) continue;
-    klass_mapping->set (klass, idx);
-    idx++;
-  }
-}
-
-struct MarkBasePosFormat1
-{
-  bool intersects (const hb_set_t *glyphs) const
-  {
-    return (this+markCoverage).intersects (glyphs) &&
-	   (this+baseCoverage).intersects (glyphs);
-  }
-
-  void closure_lookups (hb_closure_lookups_context_t *c) const {}
-
-  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
-  {
-    + hb_zip (this+markCoverage, this+markArray)
-    | hb_filter (c->glyph_set, hb_first)
-    | hb_map (hb_second)
-    | hb_apply ([&] (const MarkRecord& record) { record.collect_variation_indices (c, &(this+markArray)); })
-    ;
-
-    hb_map_t klass_mapping;
-    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, *c->glyph_set, &klass_mapping);
-
-    unsigned basecount = (this+baseArray).rows;
-    auto base_iter =
-    + hb_zip (this+baseCoverage, hb_range (basecount))
-    | hb_filter (c->glyph_set, hb_first)
-    | hb_map (hb_second)
-    ;
-
-    hb_sorted_vector_t<unsigned> base_indexes;
-    for (const unsigned row : base_iter)
-    {
-      + hb_range ((unsigned) classCount)
-      | hb_filter (klass_mapping)
-      | hb_map ([&] (const unsigned col) { return row * (unsigned) classCount + col; })
-      | hb_sink (base_indexes)
-      ;
-    }
-    (this+baseArray).collect_variation_indices (c, base_indexes.iter ());
-  }
-
-  void collect_glyphs (hb_collect_glyphs_context_t *c) const
-  {
-    if (unlikely (!(this+markCoverage).collect_coverage (c->input))) return;
-    if (unlikely (!(this+baseCoverage).collect_coverage (c->input))) return;
-  }
-
-  const Coverage &get_coverage () const { return this+markCoverage; }
-
-  bool apply (hb_ot_apply_context_t *c) const
-  {
-    TRACE_APPLY (this);
-    hb_buffer_t *buffer = c->buffer;
-    unsigned int mark_index = (this+markCoverage).get_coverage  (buffer->cur().codepoint);
-    if (likely (mark_index == NOT_COVERED)) return_trace (false);
-
-    /* Now we search backwards for a non-mark glyph */
-    hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input;
-    skippy_iter.reset (buffer->idx, 1);
-    skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks);
-    do {
-      unsigned unsafe_from;
-      if (!skippy_iter.prev (&unsafe_from))
-      {
-	buffer->unsafe_to_concat_from_outbuffer (unsafe_from, buffer->idx + 1);
-	return_trace (false);
-      }
-
-      /* We only want to attach to the first of a MultipleSubst sequence.
-       * https://github.com/harfbuzz/harfbuzz/issues/740
-       * Reject others...
-       * ...but stop if we find a mark in the MultipleSubst sequence:
-       * https://github.com/harfbuzz/harfbuzz/issues/1020 */
-      if (!_hb_glyph_info_multiplied (&buffer->info[skippy_iter.idx]) ||
-	  0 == _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]) ||
-	  (skippy_iter.idx == 0 ||
-	   _hb_glyph_info_is_mark (&buffer->info[skippy_iter.idx - 1]) ||
-	   _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx]) !=
-	   _hb_glyph_info_get_lig_id (&buffer->info[skippy_iter.idx - 1]) ||
-	   _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx]) !=
-	   _hb_glyph_info_get_lig_comp (&buffer->info[skippy_iter.idx - 1]) + 1
-	   ))
-	break;
-      skippy_iter.reject ();
-    } while (true);
-
-    /* Checking that matched glyph is actually a base glyph by GDEF is too strong; disabled */
-    //if (!_hb_glyph_info_is_base_glyph (&buffer->info[skippy_iter.idx])) { return_trace (false); }
-
-    unsigned int base_index = (this+baseCoverage).get_coverage  (buffer->info[skippy_iter.idx].codepoint);
-    if (base_index == NOT_COVERED)
-    {
-      buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
-      return_trace (false);
-    }
-
-    return_trace ((this+markArray).apply (c, mark_index, base_index, this+baseArray, classCount, skippy_iter.idx));
-  }
-
-  bool subset (hb_subset_context_t *c) const
-  {
-    TRACE_SUBSET (this);
-    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
-    const hb_map_t &glyph_map = *c->plan->glyph_map;
-
-    auto *out = c->serializer->start_embed (*this);
-    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
-    out->format = format;
-
-    hb_map_t klass_mapping;
-    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, glyphset, &klass_mapping);
-
-    if (!klass_mapping.get_population ()) return_trace (false);
-    out->classCount = klass_mapping.get_population ();
-
-    auto mark_iter =
-    + hb_zip (this+markCoverage, this+markArray)
-    | hb_filter (glyphset, hb_first)
-    ;
-
-    hb_sorted_vector_t<hb_codepoint_t> new_coverage;
-    + mark_iter
-    | hb_map (hb_first)
-    | hb_map (glyph_map)
-    | hb_sink (new_coverage)
-    ;
-
-    if (!out->markCoverage.serialize_serialize (c->serializer, new_coverage.iter ()))
-      return_trace (false);
-
-    out->markArray.serialize_subset (c, markArray, this,
-                                     (this+markCoverage).iter (),
-                                     &klass_mapping);
-
-    unsigned basecount = (this+baseArray).rows;
-    auto base_iter =
-    + hb_zip (this+baseCoverage, hb_range (basecount))
-    | hb_filter (glyphset, hb_first)
-    ;
-
-    new_coverage.reset ();
-    + base_iter
-    | hb_map (hb_first)
-    | hb_map (glyph_map)
-    | hb_sink (new_coverage)
-    ;
-
-    if (!out->baseCoverage.serialize_serialize (c->serializer, new_coverage.iter ()))
-      return_trace (false);
-
-    hb_sorted_vector_t<unsigned> base_indexes;
-    for (const unsigned row : + base_iter
-			      | hb_map (hb_second))
-    {
-      + hb_range ((unsigned) classCount)
-      | hb_filter (klass_mapping)
-      | hb_map ([&] (const unsigned col) { return row * (unsigned) classCount + col; })
-      | hb_sink (base_indexes)
-      ;
-    }
-
-    out->baseArray.serialize_subset (c, baseArray, this,
-                                     base_iter.len (),
-                                     base_indexes.iter ());
-
-    return_trace (true);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (c->check_struct (this) &&
-		  markCoverage.sanitize (c, this) &&
-		  baseCoverage.sanitize (c, this) &&
-		  markArray.sanitize (c, this) &&
-		  baseArray.sanitize (c, this, (unsigned int) classCount));
-  }
-
-  protected:
-  HBUINT16	format;			/* Format identifier--format = 1 */
-  Offset16To<Coverage>
-		markCoverage;		/* Offset to MarkCoverage table--from
-					 * beginning of MarkBasePos subtable */
-  Offset16To<Coverage>
-		baseCoverage;		/* Offset to BaseCoverage table--from
-					 * beginning of MarkBasePos subtable */
-  HBUINT16	classCount;		/* Number of classes defined for marks */
-  Offset16To<MarkArray>
-		markArray;		/* Offset to MarkArray table--from
-					 * beginning of MarkBasePos subtable */
-  Offset16To<BaseArray>
-		baseArray;		/* Offset to BaseArray table--from
-					 * beginning of MarkBasePos subtable */
-  public:
-  DEFINE_SIZE_STATIC (12);
-};
-
-struct MarkBasePos
 {
   template <typename context_t, typename ...Ts>
   typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
@@ -681,260 +63,7 @@ struct MarkBasePos
   protected:
   union {
   HBUINT16		format;		/* Format identifier */
-  MarkBasePosFormat1	format1;
+  MarkMarkPosFormat1	format1;
-  } u;
-};
-
-
-typedef AnchorMatrix LigatureAttach;	/* component-major--
-					 * in order of writing direction--,
-					 * mark-minor--
-					 * ordered by class--zero-based. */
-
-/* Array of LigatureAttach tables ordered by LigatureCoverage Index */
-struct LigatureArray : List16OfOffset16To<LigatureAttach>
-{
-  template <typename Iterator,
-	    hb_requires (hb_is_iterator (Iterator))>
-  bool subset (hb_subset_context_t *c,
-               Iterator		    coverage,
-	       unsigned		    class_count,
-	       const hb_map_t	   *klass_mapping) const
-  {
-    TRACE_SUBSET (this);
-    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
-
-    auto *out = c->serializer->start_embed (this);
-    if (unlikely (!c->serializer->extend_min (out)))  return_trace (false);
-
-    for (const auto _ : + hb_zip (coverage, *this)
-		  | hb_filter (glyphset, hb_first))
-    {
-      auto *matrix = out->serialize_append (c->serializer);
-      if (unlikely (!matrix)) return_trace (false);
-
-      const LigatureAttach& src = (this + _.second);
-      auto indexes =
-          + hb_range (src.rows * class_count)
-          | hb_filter ([=] (unsigned index) { return klass_mapping->has (index % class_count); })
-          ;
-      matrix->serialize_subset (c,
-				_.second,
-				this,
-                                src.rows,
-                                indexes);
-    }
-    return_trace (this->len);
-  }
-};
-
-struct MarkLigPosFormat1
-{
-  bool intersects (const hb_set_t *glyphs) const
-  {
-    return (this+markCoverage).intersects (glyphs) &&
-	   (this+ligatureCoverage).intersects (glyphs);
-  }
-
-  void closure_lookups (hb_closure_lookups_context_t *c) const {}
-
-  void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
-  {
-    + hb_zip (this+markCoverage, this+markArray)
-    | hb_filter (c->glyph_set, hb_first)
-    | hb_map (hb_second)
-    | hb_apply ([&] (const MarkRecord& record) { record.collect_variation_indices (c, &(this+markArray)); })
-    ;
-
-    hb_map_t klass_mapping;
-    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, *c->glyph_set, &klass_mapping);
-
-    unsigned ligcount = (this+ligatureArray).len;
-    auto lig_iter =
-    + hb_zip (this+ligatureCoverage, hb_range (ligcount))
-    | hb_filter (c->glyph_set, hb_first)
-    | hb_map (hb_second)
-    ;
-
-    const LigatureArray& lig_array = this+ligatureArray;
-    for (const unsigned i : lig_iter)
-    {
-      hb_sorted_vector_t<unsigned> lig_indexes;
-      unsigned row_count = lig_array[i].rows;
-      for (unsigned row : + hb_range (row_count))
-      {
-	+ hb_range ((unsigned) classCount)
-	| hb_filter (klass_mapping)
-	| hb_map ([&] (const unsigned col) { return row * (unsigned) classCount + col; })
-	| hb_sink (lig_indexes)
-	;
-      }
-
-      lig_array[i].collect_variation_indices (c, lig_indexes.iter ());
-    }
-  }
-
-  void collect_glyphs (hb_collect_glyphs_context_t *c) const
-  {
-    if (unlikely (!(this+markCoverage).collect_coverage (c->input))) return;
-    if (unlikely (!(this+ligatureCoverage).collect_coverage (c->input))) return;
-  }
-
-  const Coverage &get_coverage () const { return this+markCoverage; }
-
-  bool apply (hb_ot_apply_context_t *c) const
-  {
-    TRACE_APPLY (this);
-    hb_buffer_t *buffer = c->buffer;
-    unsigned int mark_index = (this+markCoverage).get_coverage  (buffer->cur().codepoint);
-    if (likely (mark_index == NOT_COVERED)) return_trace (false);
-
-    /* Now we search backwards for a non-mark glyph */
-    hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c->iter_input;
-    skippy_iter.reset (buffer->idx, 1);
-    skippy_iter.set_lookup_props (LookupFlag::IgnoreMarks);
-    unsigned unsafe_from;
-    if (!skippy_iter.prev (&unsafe_from))
-    {
-      buffer->unsafe_to_concat_from_outbuffer (unsafe_from, buffer->idx + 1);
-      return_trace (false);
-    }
-
-    /* Checking that matched glyph is actually a ligature by GDEF is too strong; disabled */
-    //if (!_hb_glyph_info_is_ligature (&buffer->info[skippy_iter.idx])) { return_trace (false); }
-
-    unsigned int j = skippy_iter.idx;
-    unsigned int lig_index = (this+ligatureCoverage).get_coverage  (buffer->info[j].codepoint);
-    if (lig_index == NOT_COVERED)
-    {
-      buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
-      return_trace (false);
-    }
-
-    const LigatureArray& lig_array = this+ligatureArray;
-    const LigatureAttach& lig_attach = lig_array[lig_index];
-
-    /* Find component to attach to */
-    unsigned int comp_count = lig_attach.rows;
-    if (unlikely (!comp_count))
-    {
-      buffer->unsafe_to_concat_from_outbuffer (skippy_iter.idx, buffer->idx + 1);
-      return_trace (false);
-    }
-
-    /* We must now check whether the ligature ID of the current mark glyph
-     * is identical to the ligature ID of the found ligature.  If yes, we
-     * can directly use the component index.  If not, we attach the mark
-     * glyph to the last component of the ligature. */
-    unsigned int comp_index;
-    unsigned int lig_id = _hb_glyph_info_get_lig_id (&buffer->info[j]);
-    unsigned int mark_id = _hb_glyph_info_get_lig_id (&buffer->cur());
-    unsigned int mark_comp = _hb_glyph_info_get_lig_comp (&buffer->cur());
-    if (lig_id && lig_id == mark_id && mark_comp > 0)
-      comp_index = hb_min (comp_count, _hb_glyph_info_get_lig_comp (&buffer->cur())) - 1;
-    else
-      comp_index = comp_count - 1;
-
-    return_trace ((this+markArray).apply (c, mark_index, comp_index, lig_attach, classCount, j));
-  }
-
-  bool subset (hb_subset_context_t *c) const
-  {
-    TRACE_SUBSET (this);
-    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
-    const hb_map_t &glyph_map = *c->plan->glyph_map;
-
-    auto *out = c->serializer->start_embed (*this);
-    if (unlikely (!c->serializer->extend_min (out))) return_trace (false);
-    out->format = format;
-
-    hb_map_t klass_mapping;
-    Markclass_closure_and_remap_indexes (this+markCoverage, this+markArray, glyphset, &klass_mapping);
-
-    if (!klass_mapping.get_population ()) return_trace (false);
-    out->classCount = klass_mapping.get_population ();
-
-    auto mark_iter =
-    + hb_zip (this+markCoverage, this+markArray)
-    | hb_filter (glyphset, hb_first)
-    ;
-
-    auto new_mark_coverage =
-    + mark_iter
-    | hb_map_retains_sorting (hb_first)
-    | hb_map_retains_sorting (glyph_map)
-    ;
-
-    if (!out->markCoverage.serialize_serialize (c->serializer, new_mark_coverage))
-      return_trace (false);
-
-    out->markArray.serialize_subset (c, markArray, this,
-                                     (this+markCoverage).iter (),
-                                     &klass_mapping);
-
-    auto new_ligature_coverage =
-    + hb_iter (this + ligatureCoverage)
-    | hb_filter (glyphset)
-    | hb_map_retains_sorting (glyph_map)
-    ;
-
-    if (!out->ligatureCoverage.serialize_serialize (c->serializer, new_ligature_coverage))
-      return_trace (false);
-
-    out->ligatureArray.serialize_subset (c, ligatureArray, this,
-                                         hb_iter (this+ligatureCoverage), classCount, &klass_mapping);
-
-    return_trace (true);
-  }
-
-  bool sanitize (hb_sanitize_context_t *c) const
-  {
-    TRACE_SANITIZE (this);
-    return_trace (c->check_struct (this) &&
-		  markCoverage.sanitize (c, this) &&
-		  ligatureCoverage.sanitize (c, this) &&
-		  markArray.sanitize (c, this) &&
-		  ligatureArray.sanitize (c, this, (unsigned int) classCount));
-  }
-
-  protected:
-  HBUINT16	format;			/* Format identifier--format = 1 */
-  Offset16To<Coverage>
-		markCoverage;		/* Offset to Mark Coverage table--from
-					 * beginning of MarkLigPos subtable */
-  Offset16To<Coverage>
-		ligatureCoverage;	/* Offset to Ligature Coverage
-					 * table--from beginning of MarkLigPos
-					 * subtable */
-  HBUINT16	classCount;		/* Number of defined mark classes */
-  Offset16To<MarkArray>
-		markArray;		/* Offset to MarkArray table--from
-					 * beginning of MarkLigPos subtable */
-  Offset16To<LigatureArray>
-		ligatureArray;		/* Offset to LigatureArray table--from
-					 * beginning of MarkLigPos subtable */
-  public:
-  DEFINE_SIZE_STATIC (12);
-};
-
-
-struct MarkLigPos
-{
-  template <typename context_t, typename ...Ts>
-  typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
-  {
-    TRACE_DISPATCH (this, u.format);
-    if (unlikely (!c->may_dispatch (this, &u.format))) return_trace (c->no_dispatch_return_value ());
-    switch (u.format) {
-    case 1: return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
-    default:return_trace (c->default_return_value ());
-    }
-  }
-
-  protected:
-  union {
-  HBUINT16		format;		/* Format identifier */
-  MarkLigPosFormat1	format1;
   } u;
 };