;;; Dragon curve based on the L-System
;;; Start: FX, Rules: (X -> X+YF), (Y -> FX-Y)

to X :n :d
ifelse :n=0 [
][
	X :n-1 :d
	rt 90
	Y :n-1 :d
	fd :d
]
end

to Y :n :d
ifelse :n=0 [
][
	fd :d
	X :n-1 :d
	lt 90
	Y :n-1 :d
]
end

to dragon :n :d
	home
	clean
	fd :d
	X :n :d
end