function easeInOutQuad(t: number, b: number, c: number, d: number) {
|
t /= d / 2
|
if (t < 1) {
|
return c / 2 * t * t + b
|
}
|
t--
|
return -c / 2 * (t * (t - 2) - 1) + b
|
}
|
|
// requestAnimationFrame for Smart Animating http://goo.gl/sx5sts
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var requestAnimFrame = (function () {
|
return window.requestAnimationFrame || function (callback) {
|
window.setTimeout(callback, 1000 / 60)
|
} //|| window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame
|
})()
|
|
/**
|
* Because it's so fucking difficult to detect the scrolling element, just move them all
|
* @param {number} amount
|
*/
|
function move(amount: number) {
|
document.documentElement.scrollTop = amount
|
//document.body.parentNode.scrollTop = amount
|
document.body.scrollTop = amount
|
}
|
|
function position() {
|
return document.documentElement.scrollTop || document.body.scrollTop
|
}
|
|
export function scrollTo(to: number, duration: number, callback?: any) {
|
const start = position();
|
const change = to - start;
|
const increment = 10;
|
let currentTime = 0;
|
duration = (typeof (duration) === 'undefined') ? 500 : duration;
|
const animateScroll = () => {
|
currentTime += increment;
|
let val = easeInOutQuad(currentTime, start, change, duration);
|
move(val);
|
if (currentTime < duration) {
|
requestAnimFrame(animateScroll)
|
} else {
|
if (callback && typeof (callback) === 'function') {
|
// the animation is done so lets callback
|
callback()
|
}
|
}
|
}
|
animateScroll()
|
}
|
