%!PS
%%BoundingBox: 0 0 300 200
/size 9 def % defines row * column (9*9 -> 81 numbers,
            % from 0 to 80)
/itoa { 2 string cvs } bind def
% visual bounding box...
% 0 0 moveto 300 0 lineto 300 200 lineto 0 200 lineto
% closepath stroke
20 150 translate
% it can be easily enhanced to support more columns and
% rows. This limit is put here just to avoid more than 2
% digits, mainly because of formatting
size size mul 99 le {
   /Helvetica findfont 14 scalefont setfont
   /ulimit size size mul def
   /sizem1 size 1 sub def
   % prepare the number list
   0 ulimit 1 sub { dup 1 add } repeat
   ulimit array astore
   /di -1 def /dj 1 def
   /ri 1 def /rj 0 def /pus true def
   0 0 moveto
   /i 0 def /j 0 def
   {  % can be rewritten a lot better :)
      0.8 setgray i 30 mul j 15 mul neg lineto stroke
      0 setgray i 30 mul j 15 mul neg moveto itoa show
      i 30 mul j 15 mul neg moveto
      pus {
         i ri add size ge {
             /ri 0 def /rj 1 def
         } if
         j rj add size ge {
             /ri 1 def /rj 0 def
         } if
         /pus false def
         /i i ri add def
         /j j rj add def
         /ri rj /rj ri def def
      } {
          i di add dup    0 le
                  exch sizem1 ge or
          j dj add dup    0 le
                  exch sizem1 ge or
             or {
                /pus true def
                /i i di add def /j j dj add def
                /di di neg def /dj dj neg def
          } {
                /i i di add def /j j dj add def
          } ifelse
      } ifelse
   } forall
   stroke showpage
} if
%%EOF