;;; Scheme Recursive Art Contest Entry
;;;
;;; Please do not include your name or personal info in this file.
;;;
;;; Title: Lanterns
;;;
;;; Description:
;;;   In the twilight sky
;;;   Leave CS behind and see
;;;   Lanterns floating by.

(define (pentagon side-length clr sides-left)
  (if (= sides-left 0) nil
  (begin
  (color clr)
  (fd side-length)
  (rt 72)
  (pentagon side-length clr (- sides-left 1)))))

(define (more how-many side-length clr)
      (if  (= how-many 0)   nil
      (begin
      (pentagon side-length clr 5)
      (rt 36)
      (more (- how-many 1) side-length clr)
      )))

(define (migrate x y)
    (penup)
    (setpos x y)
    (pendown)
    )

  (define (next-clr clr)
  (cond
  ((equal? clr "white") "red")
  ((equal? clr "red") "yellow")
  ((equal? clr "yellow") "white")
  ))

(define (beauty clr size x y)
  (if (= y 200) nil
  (begin
  (migrate x y)
  (more 10 size clr)
  (beauty (next-clr clr) (* (sin size) 20) (* (cos x) 300) (+ y 10))
  )))

(define (draw)
  (begin
  (speed 50)
  (bgcolor "#073d93")

  (beauty "white" 10 -200 -200)
  (hideturtle)
  ))

; Please leave this last line alone.  You may add additional procedures above
; this line.
(draw)