| // Copyright 2014 The Closure Library Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS-IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| /** |
| * @fileoverview A polyfill for window.requestAnimationFrame and |
| * window.cancelAnimationFrame. |
| * Code based on https://gist.github.com/paulirish/1579671 |
| */ |
| |
| goog.provide('goog.dom.animationFrame.polyfill'); |
| |
| |
| /** |
| * @define {boolean} If true, will install the requestAnimationFrame polyfill. |
| */ |
| goog.define('goog.dom.animationFrame.polyfill.ENABLED', true); |
| |
| |
| /** |
| * Installs the requestAnimationFrame (and cancelAnimationFrame) polyfill. |
| */ |
| goog.dom.animationFrame.polyfill.install = |
| goog.dom.animationFrame.polyfill.ENABLED ? function() { |
| 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) { |
| var lastTime = 0; |
| window.requestAnimationFrame = function(callback, element) { |
| var currTime = new Date().getTime(); |
| var timeToCall = Math.max(0, 16 - (currTime - lastTime)); |
| lastTime = currTime + timeToCall; |
| return window.setTimeout(function() { |
| callback(currTime + timeToCall); |
| }, timeToCall); |
| }; |
| |
| if (!window.cancelAnimationFrame) { |
| window.cancelAnimationFrame = function(id) { |
| clearTimeout(id); |
| }; |
| } |
| } |
| } : goog.nullFunction; |