+ if (Hara_kiri_group_spanner::has_interface (elts[i]))
+ Hara_kiri_group_spanner::consider_suicide (elts[i]);
+
+ Interval intersection = elts[i]->extent (this, X_AXIS);
+ intersection.intersect (iv);
+ if (elts[i]->is_live () && !intersection.is_empty ())
+ return elts[i];
+ }
+ return 0;
+}
+
+Interval
+System::part_of_line_pure_height (vsize start, vsize end, bool begin)
+{
+ Grob *alignment = get_vertical_alignment ();
+ if (!alignment)
+ return Interval ();
+
+ extract_grob_set (alignment, "elements", staves);
+ vector<Real> offsets = Align_interface::get_minimum_translations (alignment, staves, Y_AXIS, true, start, end);
+
+ Interval ret;
+ for (vsize i = 0; i < staves.size (); ++i)
+ {
+ Interval iv = begin
+ ? Axis_group_interface::begin_of_line_pure_height (staves[i], start)
+ : Axis_group_interface::rest_of_line_pure_height (staves[i], start, end);
+ if (i < offsets.size ())
+ iv.translate (offsets[i]);
+ ret.unite (iv);
+ }
+
+ Interval other_elements = begin
+ ? Axis_group_interface::begin_of_line_pure_height (this, start)
+ : Axis_group_interface::rest_of_line_pure_height (this, start, end);
+
+ ret.unite (other_elements);
+
+ return ret;
+}
+
+Interval
+System::begin_of_line_pure_height (vsize start, vsize end)
+{
+ return part_of_line_pure_height (start, end, true);
+}