;;; Scheme Recursive Art Contest Entry
;;;
;;; Please do not include your name or personal info in this file.
;;;
;;; Title: All Along the Watchtower
;;;
;;; Description:
;;;   Tower and sunset
;;;    frozen in this time; the sun
;;;    about to explode>

(define (draw)
  (speed 0)
  (penup)

  ; Background
  (bgcolor "#EEEEEE")

  ; Sunset
  (bottom 1240 "#efeeeb")
  (bottom 1130 "#f0eee7")
  (bottom 1030 "#f0eee4")
  (bottom 940 "#f1efe1")
  (bottom 870 "#f2efdd")
  (bottom 800 "#f3efda")
  (bottom 740 "#f3efd7")
  (bottom 690 "#f4efd3")
  (bottom 650 "#f5f0d0")
  (bottom 620 "#f6f0cd")
  (bottom 600 "#f6f0c9")
  (bottom 590 "#f7f0c6")

  ; Ground
  (bottom 480 "#e0e0e0")  
  (bottom 470 "#d2d2d2")
  (bottom 454 "#c4c4c4")
  (bottom 432 "#b5b5b5")
  (bottom 404 "#a7a7a7")
  (bottom 370 "#999999")
  (bottom 330 "#8b8b8b")
  (bottom 284 "#7d7d7d")
  (bottom 232 "#6e6e6e")
  (bottom 174 "#606060")
  (bottom 110 "#525252")

  ; Circle
  (setposition 40 206)
  (color "#ED4E33")
  (begin_fill)
  (circle 40)
  (end_fill)

  ; Pyramid
  (setposition 0 0)
  (left 180)

  (color "#222222")

  (define (curve1 x)
    (cond
      ((= x 5.5) 0)
      ((> x 5.5)
        (begin 
          (setposition 0 (- (* 700 (/ x 10)) 603))
          (right (arctan (- 11 x) x))
          (pendown)
          (forward 1000)
          (penup)
          (left (arctan (- 11 x) x))
          (curve1 (- x 0.3))
          ))))

  (curve1 11)

  (define (curve2 x)
  (cond
    ((= x 5.5) 0)
    ((> x 5.5)
      (begin 
        (penup)
        (setposition 0 (- (* 700 (/ x 10)) 603))
        (left (arctan (- 11 x) x))
        (pendown)
        (forward 1000)
        (penup)
        (right (arctan (- 11 x) x))
        (curve2 (- x 0.3))
        ))))

  (curve2 11)
  (exitonclick)
)

(define (bottom height c)
(begin
  (define height (* height 0.35))
  (setposition -350 -350)
  (color c)
  (begin_fill)
  (forward height)
  (rt 90)
  (forward 700)
  (rt 90)
  (forward height)
  (rt 90)
  (forward 700)
  (rt 90)
  (end_fill)
  )
)

(define (arctan a b)
  (let ((t (/ (/ a 10) (/ b 10))))
    (* (/ (+ (- t (/ (expt t 3) 3)) (/ (expt t 5) 5)) 3.14159265358979) 180)
    )
)

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