Fix some bugs in the dynamic engraver and PostScript backend

[lilypond.git] / lily / note-collision.cc

diff --git a/lily/note-collision.cc b/lily/note-collision.cc
index a3f18ab0026be756ee22c60280ea201afd0bd428..1df0a6c7aba7f8d0ff68ef226ee174fae7c089b8 100644 (file)
--- a/lily/note-collision.cc
+++ b/lily/note-collision.cc
@@ -48,7 +48,8 @@ check_meshing_chords (Grob *me,
   if (ups[0] > dps.back () + 1)
     return;
 
-  // FIXME: what's this?
+  /* Merge heads if the notes lie the same line, or if the "stem-up-note" is
+     above the "stem-down-note". */
   bool merge_possible = (ups[0] >= dps[0]) && (ups.back () >= dps.back ());
 
   /* Do not merge notes typeset in different style. */
@@ -354,7 +355,14 @@ Note_collision_interface::get_clash_groups (Grob *me)
     {
       Grob *se = elements[i];
       if (Note_column::has_interface (se))
-       clash_groups[Note_column::dir (se)].push_back (se);
+       {
+         if (!Note_column::dir (se))
+           {
+             se->programming_error ("note-column has no direction");
+           }
+         else
+           clash_groups[Note_column::dir (se)].push_back (se);
+       }
     }
 
   Direction d = UP;