- 如果使用基于 javaScript 的动画，尽量使用 requestAnimationFrame. 避免使用 setTimeout, setInterval.
使用requestAnimationFrame有什么好处？
浏览器可以优化并行的动画动作，更合理的重新排列动作序列，并把能够合并的动作放在一个渲染周期内完成，从而呈现出更流畅的动画效果。比如，通过
requestAnimationFrame()，JS动画能够和CSS动画/变换或SVG SMIL动画同步发生。另外，如果在一个浏览器标签页里运行一个动画，当这个标签页不可见时，浏览器会暂停它，这会减少CPU，内存的压力，节省电池电量各种浏览器对requestAnimationFrame的支持情况
谷歌浏览器，火狐浏览器，IE10+都实现了这个函数，即使你的浏览器很古老，上面的对requestAnimationFrame封装也能让这个方法在IE8/9上不出错。
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>Document</title></head>
<body><p id="video" width="12" height="5" ></p><button id="snap">Snap Photo</button><script>window.requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame || window.webkitRequestAnimationFrame || window.msRequestAnimationFrame;var start = null;var ele = document.getElementById("video");var progress = 0;function step(timestamp) {progress += 1;ele.style.width = progress + "%";ele.innerHTML=progress + "%";if (progress < 100) {requestAnimationFrame(step);}}requestAnimationFrame(step);document.getElementById("snap").addEventListener("click", function() {ele.style.width = "1px";progress = 0;requestAnimationFrame(step);}, false);</script></body>
</html>
/* 封装性的代码 基于各个浏览器 */
(function() {var lastTime = 0;var vendors = ['webkit', 'moz'];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);};
}());
转载处: http://www.webhek.com/post/requestanimationframe.html
转载处: https://blog.csdn.net/lsy__lsy/article/details/80624563