13 lines
327 B
Racket
13 lines
327 B
Racket
#lang frtime
|
|
(require frtime/animation)
|
|
|
|
(define-values (pos vel)
|
|
(letrec ([pos (posn-integral vel)]
|
|
[vel (posn/ (posn- mouse-pos (inf-delay pos)) 400.0)])
|
|
(values pos vel)))
|
|
|
|
(display-shapes
|
|
(list
|
|
(make-line mouse-pos pos "gray")
|
|
(make-circle pos (+ 10 (/ 400 (+ 40.0 (posn-diff mouse-pos pos)))) "blue")))
|