;;
;; particle.al: simulate one particle
;;

(define *pp* (vec3 0 0 0)) ; particle position
(define *pv* (vec3 .01 .1 0)) ; particle velocity
(define *pa* (vec3 0 -.005 0)) ; particle acceleration

(define (update-particle)
  (set! *pp* (+ *pp* *pv*))
  (set! *pv* (+ *pv* *pa*))
  )

(define (draw-particle)
  (separator
    (translate *pp*)
    (uscale .1)
    (sphere)))

(define (sim)
  (begin
    (for i 1 60 1
	 (begin
	   (world
	     (draw-particle)
	     )
	   (update-particle)
	   ))))

(sim)