/BOARD_MAX    18   def		% BOARD_SIZE - 1
/BOARD_SIZE   19   def		% number of lines drawn

/board_color   .9 .69 .28 rgbcolor def	% wood
/line_color    0 0 0 rgbcolor def		% black

/draw_board { % - => - (draw the playing surface)
    board_color setcolor		% set the board color
    clippath fill		% fill the window w/wood
    line_color setcolor		% set the line color
    0 1 BOARD_MAX {		% draw the lines
        dup 0 moveto 0 BOARD_MAX rlineto
        0 exch moveto BOARD_MAX 0 rlineto
    } for
    stroke		% stroke the path
} def