+bool
+Staff_symbol::on_line (Grob *me, int pos)
+{
+ SCM line_positions = me->get_property ("line-positions");
+ if (scm_is_pair (line_positions))
+ {
+ Real min_line = HUGE_VAL;
+ Real max_line = -HUGE_VAL;
+ for (SCM s = line_positions; scm_is_pair (s); s = scm_cdr (s))
+ {
+ Real current_line = scm_to_double (scm_car (s));
+ if (pos == current_line)
+ return true;
+ if (current_line > max_line)
+ max_line = current_line;
+ if (current_line < min_line)
+ min_line = current_line;
+
+ }
+ if (pos < min_line)
+ return (( (int) (rint (pos - min_line)) % 2) == 0);
+ if (pos > max_line)
+ return (( (int) (rint (pos - max_line)) % 2) == 0);
+
+ return false;
+ }
+ else
+ return ((abs (pos + line_count (me)) % 2) == 1);
+}
+
+Interval
+Staff_symbol::line_span (Grob *me)
+{
+ SCM line_positions = me->get_property ("line-positions");
+ Interval iv;
+
+ if (scm_is_pair (line_positions))
+ for (SCM s = line_positions; scm_is_pair (s); s = scm_cdr (s))
+ iv.add_point (scm_to_double (scm_car (s)));
+ else
+ {
+ int count = line_count (me);
+ return Interval (-count + 1, count - 1);
+ }
+
+ return iv;
+}