fl.transitions.easing.Back (ActionScript 3.0)

	Property	Defined By
		constructor : Object A reference to the class object or constructor function for a given object instance.	Object
		prototype : Object [static] A reference to the prototype object of a class or function object.	Object

	Method	Defined By
		easeIn(t:Number, b:Number, c:Number, d:Number, s:Number = 0):Number [static] The easeIn() method starts the motion by backtracking and then reversing direction and moving toward the target.	Back
		easeInOut(t:Number, b:Number, c:Number, d:Number, s:Number = 0):Number [static] The easeInOut() method combines the motion of the easeIn() and easeOut() methods to start the motion by backtracking, then reversing direction and moving toward the target, overshooting the target slightly, reversing direction again, and then moving back toward the target.	Back
		easeOut(t:Number, b:Number, c:Number, d:Number, s:Number = 0):Number [static] The easeOut() method starts the motion by moving towards the target, overshooting it slightly, and then reversing direction back toward the target.	Back
		hasOwnProperty(name:String):Boolean Indicates whether an object has a specified property defined.	Object
		isPrototypeOf(theClass:Object):Boolean Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.	Object
		propertyIsEnumerable(name:String):Boolean Indicates whether the specified property exists and is enumerable.	Object
		setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void Sets the availability of a dynamic property for loop operations.	Object
		toString():String Returns the string representation of the specified object.	Object
		valueOf():Object Returns the primitive value of the specified object.	Object

Method Detail

easeIn

()

method

public static function easeIn(t:Number, b:Number, c:Number, d:Number, s:Number = 0):Number

Language Version :

ActionScript 3.0

Runtime Versions :

AIR 1.0, Flash Player 9.0

The easeIn() method starts the motion by backtracking and then reversing direction and moving toward the target.

Parameters

	`t:Number` — Specifies the current time, between 0 and duration inclusive.

	`b:Number` — Specifies the initial value of the animation property.

	`c:Number` — Specifies the total change in the animation property.

	`d:Number` — Specifies the duration of the motion.

	`s:Number` (default = `0`) — Specifies the amount of overshoot, where the higher the value, the greater the overshoot.

Returns

Number — The value of the interpolated property at the specified time.

Example

This example animates a rectangle using the Back.easeIn easing function:

import fl.transitions.*;
import fl.transitions.easing.*;

stage.frameRate = 31;

var box:Sprite = new Sprite();
box.graphics.beginFill(Math.random() * 0xFFFFFF);
box.graphics.drawRect(0, 0, 100, 350);
box.graphics.endFill();
box.x = 50;
box.y = 10;
addChild(box);

var startValue:Number = box.x;
var finishValue:Number = 400;
var duration:Number = 3;
var myTween:Tween = new Tween(box, "x", Back.easeIn, startValue, finishValue, duration, true);
myTween.looping = true;

easeInOut

()

method

public static function easeInOut(t:Number, b:Number, c:Number, d:Number, s:Number = 0):Number

Language Version :

ActionScript 3.0

Runtime Versions :

AIR 1.0, Flash Player 9.0

The easeInOut() method combines the motion of the easeIn() and easeOut() methods to start the motion by backtracking, then reversing direction and moving toward the target, overshooting the target slightly, reversing direction again, and then moving back toward the target.

Parameters

	`t:Number` — Specifies the current time, between 0 and duration inclusive.

	`b:Number` — Specifies the initial value of the animation property.

	`c:Number` — Specifies the total change in the animation property.

	`d:Number` — Specifies the duration of the motion.

	`s:Number` (default = `0`) — Specifies the amount of overshoot, where the higher the value, the greater the overshoot.

Returns

Number — The value of the interpolated property at the specified time.

Example

This example animates a rectangle using the Back.easeInOut easing function:

import fl.transitions.*;
import fl.transitions.easing.*;

stage.frameRate = 31;

var box:Sprite = new Sprite();
box.graphics.beginFill(Math.random() * 0xFFFFFF);
box.graphics.drawRect(0, 0, 100, 350);
box.graphics.endFill();
box.x = 50;
box.y = 10;
addChild(box);

var startValue:Number = box.x;
var finishValue:Number = 400;
var duration:Number = 3;
var myTween:Tween = new Tween(box, "x", Back.easeInOut, startValue, finishValue, duration, true);
myTween.looping = true;

easeOut

()

method

public static function easeOut(t:Number, b:Number, c:Number, d:Number, s:Number = 0):Number

Language Version :

ActionScript 3.0

Runtime Versions :

AIR 1.0, Flash Player 9.0

The easeOut() method starts the motion by moving towards the target, overshooting it slightly, and then reversing direction back toward the target.

Parameters

	`t:Number` — Specifies the current time, between 0 and duration inclusive.

	`b:Number` — Specifies the initial value of the animation property.

	`c:Number` — Specifies the total change in the animation property.

	`d:Number` — Specifies the duration of the motion.

	`s:Number` (default = `0`) — Specifies the amount of overshoot, where the higher the value, the greater the overshoot.

Returns

Number — The value of the interpolated property at the specified time.

Example

This example animates a rectangle using the Back.easeOut easing function:

import fl.transitions.*;
import fl.transitions.easing.*;

stage.frameRate = 31;

var box:Sprite = new Sprite();
box.graphics.beginFill(Math.random() * 0xFFFFFF);
box.graphics.drawRect(0, 0, 100, 350);
box.graphics.endFill();
box.x = 50;
box.y = 10;
addChild(box);

var startValue:Number = box.x;
var finishValue:Number = 400;
var duration:Number = 3;
var myTween:Tween = new Tween(box, "x", Back.easeOut, startValue, finishValue, duration, true);
myTween.looping = true;

Current page: http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/fl/transitions/easing/Back.html

Comments

michael.prescott said on Mar 11, 2008 at 7:53 PM :

We need an example that shows how to set Back.easeOut()'s parameters. This example shows how to use Tween() I can find no examples that show how to set easing function parameters directly.

weesue said on Mar 19, 2008 at 6:02 AM :

How can you set the parameter s for Back.easeOut() using this example?

adbe_paul said on Mar 20, 2008 at 12:03 PM :

The Back class methods aren't really designed to be called directly, unless you're writing your own tweening engine and just want to use these tweening algorithms.

In other words, you aren't supposed to set the parameters directly in your code. Instead, you create a Tween instance describing the tween effect you want, and that Tween instance calls the appropriate tweening algorithm (such as Back.easeOut() ) as part of the process of creating the tween effect.

weesue said on Apr 9, 2008 at 8:51 AM :

I've been using the Tween class with the Back easing function but I can't see a way to set the overshoot. Back is the only easing method that has the abililty to overshoot but the Tween class makes no allowance for this extra parameter. Is there a way to set the overshoot using the Tween class?

Package	fl.transitions.easing
Class	public class Back
Inheritance	Back Object