%! Greg shapes for GraphViz/DOT

% input format :
% [ 54 36 0 36 0 0 54 0 54 36 ]  4 false yourshape
% or
% [ 54 36 0 36 0 0 54 0 54 36 ]  4 true yourshape
% [ 150 150 100 150 100 100 150 100 150 150 ]  4 true yourshape
%
% [upper right (y, x), lower right (y, x), lower left (y, x), upper left (y, x), upper right (y, x)]

/xdef {exch def} bind def

/rgv_box {
	10 dict begin
		/fflag xdef
		/sides xdef
		
		4 sides ne { stop } if
		
		aload pop
		
		newpath
		moveto
		lineto
		lineto
		lineto
		closepath
		
		pop pop
		
		fflag { fill } { stroke } ifelse
	end
} bind def

/rgv_cloud {
	10 dict begin
		/fflag xdef
		/sides xdef
	
		% Check if we have 4 sides. Else stop
		4 sides ne { stop } if
	
		% (aload) takes an array as its argument and places the individual elements 
		% of that array, and then the array itself, on the stack. Then (pop) remove
		% the top element from the stack (the array)
		aload pop

		/ury xdef /urx xdef
    /lry xdef /lrx xdef
    /lly xdef /llx xdef
    /uly xdef /ulx xdef
		pop pop

		/mx lrx llx neg add 2 div def
		/my uly lly neg add 2 div def
	
		% empty the current path and declares we are starting a new path
		newpath
		
		urx ury my neg add my 270 90 arc
		ulx mx add uly mx 0 180 arc
		llx lly my add my 90 270 arc
		lrx lry lineto
		
		closepath
		
		% The stroke operator on line four causes the path we have constructed to be
		% painted onto the current page.
		% The fill operator fills the current path with ink.
		fflag { fill } { stroke } ifelse
	end
} bind def

/rgv_flower {
	10 dict begin
		/fflag xdef
		/sides xdef
	
		% Check if we have 4 sides. Else stop
		4 sides ne { stop } if
	
		% (aload) takes an array as its argument and places the individual elements 
		% of that array, and then the array itself, on the stack. Then (pop) remove
		% the top element from the stack (the array)
		aload pop

		/ury xdef /urx xdef
    /lry xdef /lrx xdef
    /lly xdef /llx xdef
    /uly xdef /ulx xdef
		pop pop

		/mx lrx llx neg add 2 div def
		/my uly lly neg add 2 div def
	
		% empty the current path and declares we are starting a new path
		newpath
		
		% Arcs
		urx ury my neg add my 270 90 arc
		ulx mx add uly mx 0 180 arc
		llx lly my add my 90 270 arc
		lrx mx neg add lry mx 180 0 arc
		
		closepath
		
		% The stroke operator on line four causes the path we have constructed to be
		% painted onto the current page.
		% The fill operator fills the current path with ink.
		fflag { fill } { stroke } ifelse
	end
} bind def

%[ 150 150  50 150  50 100 150 100 150 150 ] 4 false rgv_box
%[ 250 250 150 250 150 200 250 200 250 250 ] 4 false rgv_flower
%[ 350 350 250 350 250 300 350 300 350 350 ] 4 false rgv_cloud
%
%.5 setgray
%[ 150 450  50 450  50 400 150 400 150 450 ] 4 true rgv_box
%.5 setgray
%[ 250 550 150 550 150 500 250 500 250 550 ] 4 true rgv_flower
%.5 setgray
%[ 350 650 250 650 250 600 350 600 350 650 ] 4 true rgv_cloud
%
%showpage