brew_cluster_piece (Grob *me, Array<Offset> bottom_points, Array<Offset> top_points)
{
#if 0
- Real blotdiameter = me->get_paper ()->get_var ("blotdiameter");
+ Real blotdiameter = me->get_paper ()->get_realvar (ly_symbol2scm ("blotdiameter"));
#else
Real blotdiameter = Staff_symbol_referencer::staff_space (me)/2;
#endif