////////////////////////////////////////////////////////////////////////////////
//
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to You 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.
//
////////////////////////////////////////////////////////////////////////////////
package mx.effects.easing
{
/**
* The Bounce class defines three easing functions to implement
* bounce motion with Flex effect classes.
*
* For more information, see http://www.robertpenner.com/profmx.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public class Bounce
{
include "../../core/Version.as";
//--------------------------------------------------------------------------
//
// Class methods
//
//--------------------------------------------------------------------------
/**
* The easeOut()
method starts the bounce motion fast,
* and then decelerates motion as it executes.
*
* @param t Specifies time.
*
* @param b Specifies the initial position of a component.
*
* @param c Specifies the total change in position of the component.
*
* @param d Specifies the duration of the effect, in milliseconds.
*
* @return Number corresponding to the position of the component.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function easeOut(t:Number, b:Number,
c:Number, d:Number):Number
{
if ((t /= d) < (1 / 2.75))
return c * (7.5625 * t * t) + b;
else if (t < (2 / 2.75))
return c * (7.5625 * (t -= (1.5 / 2.75)) * t + 0.75) + b;
else if (t < (2.5 / 2.75))
return c * (7.5625 * (t -= (2.25 / 2.75)) * t + 0.9375) + b;
else
return c * (7.5625 * (t -= (2.625 / 2.75)) * t + 0.984375) + b;
}
/**
* The easeIn()
method starts the bounce motion slowly,
* and then accelerates motion as it executes.
*
* @param t Specifies time.
*
* @param b Specifies the initial position of a component.
*
* @param c Specifies the total change in position of the component.
*
* @param d Specifies the duration of the effect, in milliseconds.
*
* @return Number corresponding to the position of the component.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function easeIn(t:Number, b:Number,
c:Number, d:Number):Number
{
return c - easeOut(d - t, 0, c, d) + b;
}
/**
* The easeInOut()
method combines the motion
* of the easeIn()
and easeOut()
methods
* to start the bounce motion slowly, accelerate motion, then decelerate.
*
* @param t Specifies time.
*
* @param b Specifies the initial position of a component.
*
* @param c Specifies the total change in position of the component.
*
* @param d Specifies the duration of the effect, in milliseconds.
*
* @return Number corresponding to the position of the component.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function easeInOut(t:Number, b:Number,
c:Number, d:Number):Number
{
if (t < d/2)
return easeIn(t * 2, 0, c, d) * 0.5 + b;
else
return easeOut(t * 2 - d, 0, c, d) * 0.5 + c * 0.5 + b;
}
}
}