smooth-scroll
Version:
Animate scrolling to anchor links
34 lines (31 loc) • 1.17 kB
JavaScript
/**
* requestAnimationFrame() polyfill
* By Erik Möller. Fixes from Paul Irish and Tino Zijdel.
* @link http://paulirish.com/2011/requestanimationframe-for-smart-animating/
* @link http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating
* @license MIT
*/
(function() {
var lastTime = 0;
var vendors = ['ms', 'moz', 'webkit', 'o'];
for(var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame'];
window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame'] ||
window[vendors[x]+'CancelRequestAnimationFrame'];
}
if (!window.requestAnimationFrame) {
window.requestAnimationFrame = function(callback, element) {
var currTime = new Date().getTime();
var timeToCall = Math.max(0, 16 - (currTime - lastTime));
var id = window.setTimeout(function() { callback(currTime + timeToCall); },
timeToCall);
lastTime = currTime + timeToCall;
return id;
};
}
if (!window.cancelAnimationFrame) {
window.cancelAnimationFrame = function(id) {
clearTimeout(id);
};
}
}());