+/draw_volta % w last
+{
+ /last exch def
+ /volta_w exch def
+ staffheight 2 div /volta_h exch def
+ volta_t setlinewidth
+% urg: the only Level-2 PS, check effect in print
+% true setstrokeadjust
+ 1 setlinecap
+ 1 setlinejoin
+ 0 0 moveto
+ 0 volta_h lineto
+ volta_w volta_h lineto
+ last 0 eq {
+ volta_w 0 lineto
+ } if
+ stroke
+} bind def
+