-ADD_INTERFACE (Note_column, "note-column-interface",
- "Stem and noteheads combined",
- "arpeggio note-heads rest-collision rest horizontal-shift stem accidentals force-hshift");
+/* If a note-column contains a cross-staff stem then
+ nc->extent (Y_AXIS, refp) will not consider the extent of the stem.
+ If you want the extent of the stem to be included (and you are safe
+ from any cross-staff issues) then call this function instead. */
+Interval
+Note_column::cross_staff_extent (Grob *me, Grob *refp)
+{
+ Interval iv = me->extent (refp, Y_AXIS);
+ if (Grob *s = get_stem (me))
+ iv.unite (s->extent (refp, Y_AXIS));
+
+ return iv;
+}
+
+ADD_INTERFACE (Note_column,
+ "Stem and noteheads combined.",
+
+ /* properties */
+ "arpeggio "
+ "force-hshift "
+ "horizontal-shift "
+ "ignore-collision "
+ "note-heads "
+ "rest "
+ "rest-collision "
+ "stem "
+ );