;;; Scheme Recursive Art Contest Entry
;;;
;;; Please do not include your name or personal info in this file.
;;;
;;; Title: Recursive what?
;;;
;;; Description:
;;; What do you see in this pattern?
;;; Circles? Waves?
;;; Or, Wi-Fis? 

(define (wave radius cx cy)
  (define num 5)
  (define sx (- cx (* radius 0.8660254)))
  (define sy (+ cy (* radius 0.5)))
  (define (helper ccx ccy n)
    (if (= n 0)
      ()
      (begin
        (pu)
        (setpos ccx ccy)
        (pd)
        (seth 211)
        (define sum (+ (abs cx) (abs cy) (abs (+ cx cy)) 0.1))
        (define red (/ (abs (+ cx cy)) (* sum 0.8)))
        (define green (/ (abs cy) (* sum 0.8)))
        (define blue (/ (abs cx) (* sum 0.8)))
        (color (rgb red green blue))
        (circle (* radius (/ n num)) -118)
        (helper (/ (+ (* sx (- n 1)) (* cx (- num (- n 1)))) num)
                (/ (+ (* sy (- n 1)) (* cy (- num (- n 1)))) num)
                (- n 1)
        )
      )
    )
  )
  (helper sx sy num)
)


(define (column-wave radius row cx cy)
  (if (= row 0)
    ()
    (begin
      (wave radius cx cy)
      (column-wave radius (- row 1) cx (- cy radius))
    )
  )
)

(define (seigaiha radius row column sx sy)
  (define (helper i ccolumn cx cy)
    (if (= ccolumn 0)
      ()
      (begin
        (column-wave radius row cx cy)
        (if (= (remainder i 2) 0)
          (helper (+ i 1) (- ccolumn 1) (+ cx radius) (+ cy (* radius 0.5)))
          (helper (+ i 1) (- ccolumn 1) (+ cx radius) (- cy (* radius 0.5)))
        )
      )
    )
  )
  (helper 0 column sx sy)
)

(define (draw)
  (speed 0)
  (seigaiha 50 15 25 -600 300)
  (hideturtle)
  (exitonclick)
)

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