ZXASCII
AUTO -1
PROG demos:graphics/pattern3
CHANGED FALSE
10 gs=16,g=gs/2
20 for x=0 to scrw/gs:
	   for y=0 to scrh/gs:
				   for i=0 to 1:
							   d=int(rnd*2):
										plot x*gs+i*g+g*d,y*gs+i*g+g*not d:
										draw gs*not d,gs*d:
							next i:
				next y:
	next x
30 for x=0 to scrw-1 step g-1:
	   for y=0 to scrh-1 step g-1:
40       if point(x,y)=8 then
							   fill ink(rnd*14)+1;x,y
50    next y:
	next x:
	wait keydown:
	cls 8:
	GO To 10