x.ps

%!

% Load font, set font size and set current font
% This has to be done before defining dx, since it calculates font width
/Courier findfont
16 scalefont
setfont

% Define constants and variables used
/pageWidth 595 def
/pageHeight 842 def
/size 38 def						% size of the grid
/padding 0 def						% padding outside the grid
/dx (X) stringwidth pop 2 add def  	% calculate and store the width of "X"

% x_pos and y_pos defines the starting point of the drawing
% remember: postscript has origo (0,0) in lower left corner
% we calculate the starting position to place the drawing in the center of the A4 page
/boxwidth size dx mul def
/x_pos pageWidth 2 div boxwidth 2 div sub dx 2 div sub def
/y_pos pageHeight 2 div boxwidth 2 div sub dx 2 div sub def

% Set the document to A4 page size
<< /PageSize [pageWidth pageHeight] >> setpagedevice

0 1 size {
	/i exch def
	0 1 size {
		/j exch def
		x_pos j dx mul add y_pos moveto 

		i 0 eq size i eq or
		j 0 eq size j eq or or
		i j eq size i sub j eq or or
		{
			(X) show
		} if
	} for
	/y_pos y_pos dx add def
} for

showpage