% Admittedly silly but instructive example; input fix_page; def silly_display expr p = draw p shifted (.5,.25) withcolor red; draw p; pickup pensquare scaled .5pt; bboxmargin:=0; draw bbox p withcolor blue; pickup pencircle scaled .5pt; draw lrcorner p -- ulcorner p withcolor blue; draw urcorner p -- llcorner p withcolor blue; enddef; beginfig(101); silly_display fix_page(1, "storyx.mpy"); endfig; beginfig(102); silly_display fix_page(2, "storyx.mpy"); endfig; beginfig(103); silly_display fix_page(3, "storyx.mpy"); endfig; bye.