Episode 29: Tweening Part 1
| author |
Steve Losh <steve@stevelosh.com> |
| date |
Tue, 28 Jun 2016 21:45:49 +0000 |
| parents |
(none) |
| children |
783609c42ef0 |
(in-package #:coding-math.tween)
(defun tween-linear (start amount duration time)
(let ((time (/ time duration)))
(+ start (* amount time))))
(defun tween-quadratic-in (start amount duration time)
(let ((time (/ time duration)))
(+ start (* amount (* time time)))))
(defun tween-quadratic-out (start amount duration time)
(let ((time (/ time duration)))
(+ start (* (- amount) (* time (- time 2))))))