% --- start of displayed preamble in the book --- input boxes % --- end of displayed preamble in the book --- defaultfont:="ptmr8r"; warningcheck:=0; beginfig(1) boxjoin(a.n=b.s-(20,60)); boxit.one("One");circleit.two("Two"); drawboxes(one,two); drawarrow one.c--two.c cutbefore bpath one cutafter bpath two; boxjoin(); boxit.three("Three");three.w=one.e+(20,0); fill bpath three withcolor blue; draw bpath three;draw pic(three) withcolor white; endfig; end;