27 lines
1.0 KiB
JavaScript
27 lines
1.0 KiB
JavaScript
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// make sure requestAnimationFrame and cancelAnimationFrame are defined
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// polyfill for browsers without native support
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// by Opera engineer Erik Möller
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(function () {
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var lastTime = 0;
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var vendors = ['webkit', 'moz', 'ms', 'o'];
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for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
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window.requestAnimationFrame = window[vendors[x] + 'RequestAnimationFrame'];
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window.cancelAnimationFrame = window[vendors[x] + 'CancelAnimationFrame'] ||
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window[vendors[x] + 'CancelRequestAnimationFrame'];
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}
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if (!window.requestAnimationFrame) {
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window.requestAnimationFrame = function (callback) {
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var currTime = new Date().getTime();
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var timeToCall = Math.max(0, 16 - (currTime - lastTime));
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var id = window.setTimeout(function () { return callback(currTime + timeToCall); }, timeToCall);
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lastTime = currTime + timeToCall;
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return id;
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};
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}
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if (!window.cancelAnimationFrame) {
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window.cancelAnimationFrame = function (id) {
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clearTimeout(id);
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};
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}
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})();
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