(define (side length level)
  (if (<= level 0)
    (draw length)
    (begin
      (side (/ length 3) (- level 1))
      (turn -60)
      (side (/ length 3) (- level 1))
      (turn 120)
      (side (/ length 3) (- level 1))
      (turn -60)
      (side (/ length 3) (- level 1)))))

(define (snowflake length level)
  ;; Go down to allow big shapes.
  (turn 90)
  (move (- (/ length 2)))
  (turn -30)
  ;; Draw the shape.
  (side length (- level 1))
  (turn 120)
  (side length (- level 1))
  (turn 120)
  (side length (- level 1))
  (turn 120)
  ;; Go back to the middle (not actually needed).
  (turn 30)
  (move (/ length 2))
  (turn -90))