(load "stk-turtle-stuff")

(define (db d s)
  (setheading d)
  (pendown)
  (begin-fill)
  (left 90)
  (forward (/ s 16))
  (right 90)
  (forward s)
  (right 90)
  (forward (/ s 8))
  (right 90)
  (forward s)
  (right 90)
  (forward (/ s 16))
  (left 90)
  (end-fill)
  (line2 d s))
  

(define (line2 d s)
  (pendown)
  (setheading d)
  (forward s)
  (penup))

(define (rana)
  (- 38 (random 16)))

(define (tree n d)
  (cond ((< n 1)
      (cond ((> 2 (random 3)) (vine (random 20)))))
      (else
       (db d (* n 10))
       (define loc (pos))
       (tree (+ n (ran2)) (+ d (rana)))
       (setxy (car loc) (cadr loc))
       (tree (+ n (ran2)) (- d (rana))))))

(define (ran2)
  (-  (random 2) 2))  
  
(define (vine n)
  (cond ( (> n 0)
  (line2 (- 205 (random 50)) 8)
  (vine (- n 1)))))

(sety -200)
(tree 10 0)