(* La courbe de Hilbert cf http://fr.wikipedia.org/wiki/Courbe_de_Hilbert *) def l(n) { if n { turnright 90 r(n-1) forward 8 turnleft 90 l(n-1) forward 8 l(n-1) turnleft 90 forward 8 r(n-1) turnright 90 } } def r(n) { if n { turnleft 90 l(n-1) forward 8 turnright 90 r(n-1) forward 8 r(n-1) turnright 90 forward 8 l(n-1) turnleft 90 } } penup forward -250 turnleft 90 forward -250 pendown l(6)