FastEase.as 5.17 KB
/**
 * VERSION: 1.0
 * DATE: 10/18/2009
 * AS3
 * UPDATES AND DOCUMENTATION AT: http://www.TweenMax.com
 **/
package com.greensock.easing {
	import flash.utils.Dictionary;
	import com.greensock.TweenLite;
/**
 * TweenMax (AS3 only) has built-in algorithms that speed up the processing of certain easing equations but in order
 * to take advantage of those optimizations, you must activate the easing equations first (you only need to
 * activate them ONCE in your swf). The following easing equations from the com.greensock.easing package are 
 * eligible for activation:
 * <code>
 * <ul>
 *     	<li>Linear (easeIn, easeOut, easeInOut, and easeNone)</li>
 * 		<li>Quad (easeIn, easeOut, and easeInOut)</li>
 * 		<li>Cubic (easeIn, easeOut, and easeInOut)</li>
 * 		<li>Quart (easeIn, easeOut, and easeInOut)</li>
 * 		<li>Quint (easeIn, easeOut, and easeInOut)</li>
 * 		<li>Strong (easeIn, easeOut, and easeInOut)</li>
 * </ul><br />
 * </code>
 * 
 * <b>EXAMPLE</b><br /><br />
 * 
 * <code>
 * 		import com.greensock.easing.*;<br /><br />
 * 		
 * 		//activate the optimized ease classes<br />
 * 		FastEase.activate([Strong, Linear, Quad]);<br /><br />
 * 
 * 		//then tween as usual (you don't have to do anything special in your tweens)<br />
 * 		TweenMax.to(mc, 2, {x:200, ease:Linear.easeNone});<br /><br />
 * </code>
 * 
 * Once activated, the easing calculations run about <b>35-80% faster!</b> Keep in mind that the easing calculations are only one small part
 * of the tweening engine, so you may only see a 2-15% improvement overall depending on the equation and quantity of simultaneous tweens.
 * 
 * Notes: <br />
 * <ul>
 * 		<li>TweenLite does <b>NOT</b> have the internal algorithms in place to take advantage of optimized eases at this time (to conserve file size).</li>
 * 		<li>Activating an ease multiple times doesn't hurt or help</li>
 * </ul>
 * 
 * @param easeClasses An Array containing the easing classes to activate, like [Strong, Linear, Quad]. It will automatically activate the easeIn, easeOut, easeInOut, and (if available) easeNone easing equations for each class in the Array.
 */
	public class FastEase {
		
		/**
		 * Normally you should use the <code>FastEase.activate()</code> method to activate optimized eases, but if you
		 * want to activate an ease that is NOT in the com.greensock.easing package (for example 
		 * <code>fl.motion.easing.Quadratic</code>), you can register individual easing equations with
		 * this method. For example:
		 * 
		 * <code>
		 * 		import fl.motion.easing.Quadratic;<br />
		 * 		import com.greensock.easing.FastEase;<br /><br />
		 * 
		 * 		FastEase.activateEase(Quadratic.easeIn, 1, 1);
		 * </code>
		 * 
		 * @param ease The easing equation (function) to activate. For example, Quadratic.easeIn
		 * @param type The type of ease (in, out, or inOut) where easeIn is 1, easeOut is 2, and easeInOut is 3.
		 * @param power The magnitude or power of the ease. For example, Linear is 0, Quad is 1, Cubic is 2, Quart is 3 and Quint and Strong are 4.
		 */
		public static function activateEase(ease:Function, type:int, power:uint):void {
			TweenLite.fastEaseLookup[ease] = [type, power];
		}
		
		/**
		 * TweenMax (AS3 only) has built-in algorithms that speed up the processing of certain easing equations but in order
		 * to take advantage of those optimizations, you must activate the easing equations first (you only need to
		 * activate them ONCE in your swf). The following easing equations from the com.greensock.easing package are 
		 * eligible for activation:
		 * <code>
		 * <ul>
		 *     	<li>Linear (easeIn, easeOut, easeInOut, and easeNone)</li>
		 * 		<li>Quad (easeIn, easeOut, and easeInOut)</li>
		 * 		<li>Cubic (easeIn, easeOut, and easeInOut)</li>
		 * 		<li>Quart (easeIn, easeOut, and easeInOut)</li>
		 * 		<li>Quint (easeIn, easeOut, and easeInOut)</li>
		 * 		<li>Strong (easeIn, easeOut, and easeInOut)</li>
		 * </ul><br />
		 * </code>
		 * 
		 * <b>EXAMPLE</b><br /><br />
		 * 
		 * <code>
		 * 		import com.greensock.easing.*;<br /><br />
		 * 		
		 * 		FastEase.activate([Strong, Linear, Quad]);<br /><br />
		 * </code>
		 * 
		 * Notes: <br />
		 * <ul>
		 * 		<li>TweenLite does <b>NOT</b> have the internal algorithms in place to take advantage of optimized eases at this time (to conserve file size).</li>
		 * 		<li>Activating an ease multiple times doesn't hurt or help</li>
		 * </ul>
		 * 
		 * @param easeClasses An Array containing the easing classes to activate, like [Strong, Linear, Quad]. It will automatically activate the easeIn, easeOut, easeInOut, and (if available) easeNone easing equations for each class in the Array.
		 */
		public static function activate(easeClasses:Array):void {
			var i:int = easeClasses.length, easeClass:Object;
			while (i--) {
				easeClass = easeClasses[i];
				if (easeClass.hasOwnProperty("power")) {
					activateEase(easeClass.easeIn, 1, easeClass.power);
					activateEase(easeClass.easeOut, 2, easeClass.power);
					activateEase(easeClass.easeInOut, 3, easeClass.power);
					if (easeClass.hasOwnProperty("easeNone")) {
						activateEase(easeClass.easeNone, 1, 0);
					}
				}
			}
		}
		
	}
}