1 files changed, 67 insertions, 4 deletions

diff --git a/thirdparty/harfbuzz/src/hb-ot-kern-table.hh b/thirdparty/harfbuzz/src/hb-ot-kern-table.hh
index 39444d803f..b87ac8f494 100644
--- a/thirdparty/harfbuzz/src/hb-ot-kern-table.hh
+++ b/thirdparty/harfbuzz/src/hb-ot-kern-table.hh
@@ -86,6 +86,16 @@ struct KernSubTableFormat3
 				  leftClassCount * rightClassCount));
   }
 
+  template <typename set_t>
+  void collect_glyphs (set_t &left_set, set_t &right_set, unsigned num_glyphs) const
+  {
+    set_t set;
+    if (likely (glyphCount))
+      set.add_range (0, glyphCount - 1);
+    left_set.union_ (set);
+    right_set.union_ (set);
+  }
+
   protected:
   KernSubTableHeader
 		header;
@@ -135,16 +145,29 @@ struct KernSubTable
     switch (subtable_type) {
     case 0:	return_trace (c->dispatch (u.format0));
 #ifndef HB_NO_AAT_SHAPE
-    case 1:	return_trace (u.header.apple ? c->dispatch (u.format1, std::forward<Ts> (ds)...) : c->default_return_value ());
+    case 1:	return_trace (c->dispatch (u.format1, std::forward<Ts> (ds)...));
 #endif
     case 2:	return_trace (c->dispatch (u.format2));
 #ifndef HB_NO_AAT_SHAPE
-    case 3:	return_trace (u.header.apple ? c->dispatch (u.format3, std::forward<Ts> (ds)...) : c->default_return_value ());
+    case 3:	return_trace (c->dispatch (u.format3, std::forward<Ts> (ds)...));
 #endif
     default:	return_trace (c->default_return_value ());
     }
   }
 
+  template <typename set_t>
+  void collect_glyphs (set_t &left_set, set_t &right_set, unsigned num_glyphs) const
+  {
+    unsigned int subtable_type = get_type ();
+    switch (subtable_type) {
+    case 0:	u.format0.collect_glyphs (left_set, right_set, num_glyphs); return;
+    case 1:	u.format1.collect_glyphs (left_set, right_set, num_glyphs); return;
+    case 2:	u.format2.collect_glyphs (left_set, right_set, num_glyphs); return;
+    case 3:	u.format3.collect_glyphs (left_set, right_set, num_glyphs); return;
+    default:	return;
+    }
+  }
+
   bool sanitize (hb_sanitize_context_t *c) const
   {
     TRACE_SANITIZE (this);
@@ -318,8 +341,9 @@ struct kern
     }
   }
 
-  bool apply (AAT::hb_aat_apply_context_t *c) const
-  { return dispatch (c); }
+  bool apply (AAT::hb_aat_apply_context_t *c,
+	      const AAT::kern_accelerator_data_t *accel_data = nullptr) const
+  { return dispatch (c, accel_data); }
 
   template <typename context_t, typename ...Ts>
   typename context_t::return_t dispatch (context_t *c, Ts&&... ds) const
@@ -343,6 +367,41 @@ struct kern
     return_trace (dispatch (c));
   }
 
+  AAT::kern_accelerator_data_t create_accelerator_data (unsigned num_glyphs) const
+  {
+    switch (get_type ()) {
+    case 0: return u.ot.create_accelerator_data (num_glyphs);
+#ifndef HB_NO_AAT_SHAPE
+    case 1: return u.aat.create_accelerator_data (num_glyphs);
+#endif
+    default:return AAT::kern_accelerator_data_t ();
+    }
+  }
+
+  struct accelerator_t
+  {
+    accelerator_t (hb_face_t *face)
+    {
+      hb_sanitize_context_t sc;
+      this->table = sc.reference_table<kern> (face);
+      this->accel_data = this->table->create_accelerator_data (face->get_num_glyphs ());
+    }
+    ~accelerator_t ()
+    {
+      this->table.destroy ();
+    }
+
+    hb_blob_t *get_blob () const { return table.get_blob (); }
+
+    bool apply (AAT::hb_aat_apply_context_t *c) const
+    {
+      return table->apply (c, &accel_data);
+    }
+
+    hb_blob_ptr_t<kern> table;
+    AAT::kern_accelerator_data_t accel_data;
+  };
+
   protected:
   union {
   HBUINT32		version32;
@@ -356,6 +415,10 @@ struct kern
   DEFINE_SIZE_UNION (4, version32);
 };
 
+struct kern_accelerator_t : kern::accelerator_t {
+  kern_accelerator_t (hb_face_t *face) : kern::accelerator_t (face) {}
+};
+
 } /* namespace OT */