/setup { %  - => -  (establish coordinate system)
        clippath pathbbox		% cliche 
        scale		% scale to window size
        pop pop		% discard x and y

        .5 .5 translate		% translate origin
        0 0 moveto		% move to center
        0.01 setlinewidth		% set line thickness
        2 setlinejoin		% set endcap style
        /grayval .65 def		% initialize gray value var
        grayval setgray		% set gray value
} def        

/triangle { % - => path (create a triangular path)
        newpath		% clear path
        .15 0 moveto
        -.0625 .5 lineto
        .0625 -.5 lineto
        gsave		% save path
                stroke		% stroke it
        grestore		% restore path
} def

/makewin { %  - => - (builds a test window)
    /win framebuffer /new DefaultWindow send def  % cliche
    {
         /PaintClient {		% damage causes 
		%  /PaintClient to be called 
              setup
              1 1 12 {		% repeat 12 times
                      triangle		% draw triangle
                      /grayval grayval .05 sub def	% decrease gray
                      grayval setgray		% set gray value
                      fill		% fill triangle
                      30 rotate		% rotate through 30*12 
              } for
         } def
         /FrameLabel ( Workspace ) def    	% label the window
         /PaintIcon {		% define the icon image
              erasepage		% clear the canvas
              PaintClient		% call /PaintClient
              .9 strokecanvas		% stroke canvas border
         } def
    } win send

    /reshapefromuser win send 		% size it
    /map win send 		% make it visible
} def

makewin		% run the program