%!

% --- procedure ---------------------------------------------

% argument: s
% returns an array of points in a square s on a side, centered at (0,0)
/square { 1 dict begin
  /s exch def
  [
    [ s -0.5 mul dup ]
    [ s 0.5 mul dup neg ]
    [ s 0.5 mul dup ]
    [ s -0.5 mul dup neg ]
  ] 
end } def

% --- sample usage -------------------------------------------

/S 72 def
S dup scale
1 S div setlinewidth

4.25 5.5 translate

newpath
/s 2 square def
/c s 3 get def
c 0 get c 1 get moveto
0 1 s length 1 sub { /i exch def
  /c s i get def
  c 0 get c 1 get lineto
} for
closepath
stroke