X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fsemi-tie-column.cc;h=508df73a9f5fe8865ffe40e1fc45af929013b4b2;hb=38d7d319eabc906e82fb42002678c6d42a23b6f7;hp=70d431f10591237996c81dd50bdac51b8824dae2;hpb=3f8485925e8c879fe4c9ae86acef9804126c3b91;p=lilypond.git

diff --git a/lily/semi-tie-column.cc b/lily/semi-tie-column.cc
index 70d431f105..508df73a9f 100644
--- a/lily/semi-tie-column.cc
+++ b/lily/semi-tie-column.cc
@@ -3,7 +3,7 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c) 2005--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
+  (c) 2005--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
 */
 
@@ -21,7 +21,7 @@
 
 
 ADD_INTERFACE (Semi_tie_column,
-	      "The interface for a column of l.v. ties.",
+	      "The interface for a column of l.v. (laissez vibrer) ties.",
 
 	      /* properties */
 	      "positioning-done "
@@ -72,4 +72,23 @@ Semi_tie_column::calc_positioning_done (SCM smob)
   return SCM_BOOL_T;
 }
   
+MAKE_SCHEME_CALLBACK (Semi_tie_column, calc_head_direction, 1);
+SCM
+Semi_tie_column::calc_head_direction (SCM smob)
+{
+  Grob *me = unsmob_grob (smob);
 
+  extract_grob_set (me, "ties", ties);
+  Direction d = LEFT;
+  for (vsize i = 0; i < ties.size (); i++)
+    {
+      Direction this_d = to_dir (ties[i]->get_property ("head-direction"));
+      if (i > 0 && d != this_d)
+	{
+	  programming_error ("all semi-ties in a semi-tie-column should have the same head-direction");
+	  return scm_from_int (d);
+	}
+      d = this_d;
+    }
+  return scm_from_int (d);
+}