Package	com.greensock.easing
Class	public class Ease
Inheritance	Ease Object
Subclasses	Linear, SlowMo, SteppedEase

All Ease instances have a getRatio() method that is responsible for the translation of the progress ratio which the tween typically feeds in. End users almost never need to directly feed any values to or get any values from an Ease instance - the tweens will do that internally.

The base Ease class handles most of the common power-based easeIn/easeOut/eaesInOut calculations (like Linear, Quad, Cubic, Quart, Quint, and Strong) internally. You can define a separate function that uses what was considered the 4 standard easing parameters by Adobe and many others (time, start, change, duration) and Ease will serve as a proxy in order to maximize backwards compatibility and usability. For example, if you have a custom method that you created like this:

function myEase(t:Number, s:Number, c:Number, d:Number):Number {
    return s+(t=t/d);
}

import com.greensock.*;
import com.greensock.easing.*;
 
TweenLite.to(mc, 5, {x:600, ease:new Ease(myEase)});

In the above example, the anytime the Ease's getRatio() method is called, it would feed the first parameter as a ratio between 0 and 1 and the rest of the 3 parameters would always be 0, 1, 1. This is all done transparently by TweenLite/TweenMax, so you really shouldn't need to worry about this.

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