+
+/*
+ Extend the spanner over its Tie constituents.
+*/
+MAKE_SCHEME_CALLBACK (Tie_column, before_line_breaking, 1);
+SCM
+Tie_column::before_line_breaking (SCM smob)
+{
+ Spanner *me = dynamic_cast<Spanner *> (unsmob_grob (smob));
+ for (SCM s = me->get_property ("ties"); scm_is_pair (s); s = scm_cdr (s))
+ {
+ Spanner *tie = dynamic_cast<Spanner *> (unsmob_grob (scm_car (s)));
+ Direction dir = LEFT;
+ do
+ {
+ if (dir * tie->get_bound (dir)->get_column ()->get_rank ()
+ > dir * me->get_bound (dir)->get_column ()->get_rank ())
+ {
+ me->set_bound (dir, Tie::head (tie, dir));
+ }
+ }
+ while (flip (&dir) != LEFT);
+ }
+ return SCM_UNSPECIFIED;
+}
+
+ADD_INTERFACE (Tie_column, "tie-column-interface",
+ "Object that sets directions of multiple ties in a tied chord",
+ "direction");
+