animare/lib/module/plugins/ease/easeInOut.js

Advanced animation library for modern JavaScript.

import{bounce,wobble}from'./ease.js';const easeInOut={back:function(){let c1=arguments.length>0&&arguments[0]!==undefined?arguments[0]:1.70158;return t=>{const c2=c1*1.525;return t<0.5?Math.pow(2*t,2)*((c2+1)*2*t-c2)/2:(Math.pow(2*t-2,2)*((c2+1)*(t*2-2)+c2)+2)/2;};},bounce:t=>t<0.5?(1-bounce(1-2*t))/2:(1+bounce(2*t-1))/2,circ:t=>t<0.5?(1-Math.sqrt(1-Math.pow(2*t,2)))/2:(Math.sqrt(1-Math.pow(-2*t+2,2))+1)/2,cubic:t=>t<0.5?4*t*t*t:1-Math.pow(-2*t+2,3)/2,elastic:t=>{const c5=2*Math.PI/4.5;return t===0?0:t===1?1:t<0.5?-(Math.pow(2,20*t-10)*Math.sin((20*t-11.125)*c5))/2:Math.pow(2,-20*t+10)*Math.sin((20*t-11.125)*c5)/2+1;},expo:t=>t===0?0:t===1?1:t<0.5?Math.pow(2,20*t-10)/2:(2-Math.pow(2,-20*t+10))/2,sine:t=>-(Math.cos(Math.PI*t)-1)/2,quad:t=>t<0.5?2*t*t:1-Math.pow(-2*t+2,2)/2,quart:t=>t<0.5?8*t*t*t*t:1-Math.pow(-2*t+2,4)/2,quint:t=>t<0.5?16*t*t*t*t*t:1-Math.pow(-2*t+2,5)/2,poly:n=>{return t=>t<0.5?Math.pow(2,n-1)*Math.pow(t,n):1-Math.pow(-2*t+2,n)/2;},wobble(){let bounciness=arguments.length>0&&arguments[0]!==undefined?arguments[0]:1;return inOut(wobble(bounciness));}};/**
 * Makes any easing function symmetrical. The easing function will run
 * forwards for half of the duration, then backwards for the rest of the
 * duration.
 */function inOut(easing){return t=>{if(t<0.5)return easing(t*2)/2;return 1-easing((1-t)*2)/2;};}export default easeInOut;