+MAKE_SCHEME_CALLBACK (Slur, pure_height, 3);
+SCM
+Slur::pure_height (SCM smob, SCM start_scm, SCM end_scm)
+{
+ Grob *me = unsmob_grob (smob);
+ int start = scm_to_int (start_scm);
+ int end = scm_to_int (end_scm);
+ Real height = robust_scm2double (me->get_property ("height-limit"), 2.0);
+
+ extract_grob_set (me, "note-columns", encompasses);
+ Interval ret;
+
+ Grob *parent = me->get_parent (Y_AXIS);
+ if (common_refpoint_of_array (encompasses, me, Y_AXIS) != parent)
+ /* this could happen if, for example, we are a cross-staff slur.
+ in this case, we want to be ignored */
+ return ly_interval2scm (Interval ());
+
+ for (vsize i = 0; i < encompasses.size (); i++)
+ {
+ Interval d = encompasses[i]->pure_height (parent, start, end);
+ if (!d.is_empty ())
+ ret.unite (d);
+ }
+
+ ret.widen (height * 0.5);
+ return ly_interval2scm (ret);
+}
+