package org.as3lib.kitchensync.easing
  {
          

<p>@ax-lib-flex-animation-code-10-org-as3lib-kitchensync-easing-Bounce produces values that would cause a moving subject to bounce against the starting or ending points like a rubber ball.</p> <p>The easing classes provide static methods for interpolating the change between two values over time. Each class handles the interpolation, or easing, differently. Each class typically contains three methods - <code>easeIn()</code>, <code>easeOut()</code> and <code>easeInOut()</code> - which vary the rate of change of the values. Most of the easing functions produce values as a percentage - a number between 0.0 and 1.0</p>
author: modified by Mims H. Wright, 2007
author: (c) 2003 Robert Penner, all rights reserved. - This work is subject to the terms in www.robertpenner.com/easing_terms_of_use.html
see: www.robertpenner.com/easing_terms_of_use.html
see: www.robertpenner.com/easing/
see: EasingUtil

  
          public class @ax-lib-flex-animation-code-10-org-as3lib-kitchensync-easing-Bounce
          {
                  

The constants defined in this class are used to control the bouncing algorithm

  
                  private static const BOUNCE_CONST:Number   = 7.5625;
                  private static const THRESHOLDx1:Number    = 0.363636;
                  private static const THRESHOLDx15:Number   = 0.545454;
                  private static const THRESHOLDx2:Number    = 0.727272;
                  private static const THRESHOLDx225:Number  = 0.818181;
                  private static const THRESHOLDx25:Number   = 0.909090;
                  private static const THRESHOLDx2625:Number = 0.954545;
                  
                  private static const BOUNCE1:Number = 0.75;
                  private static const BOUNCE2:Number = 0.9375;
                  private static const BOUNCE3:Number = 0.984375;
                  
              

easeIn starts out slow and increases in speed towards the end of the duration. The bouncing will appear to increase in height.
parameter: timeElapsed The time since the tween began in milliseconds or frames.
parameter: duration The duration of the tween, in milliseconds or frames.
returns: percentage complete - between 0.0 and 1.0

   
                  public static function easeIn(timeElapsed:Number, duration:Number):Number
                  {
                          return 1 - easeOut(duration-timeElapsed, duration);
                  }
          
          
             

easeOut starts out fast and decreases in speed towards the end of the duration. The bouncing will appear to decrease in height.
parameter: timeElapsed Specifies the time since the tween began in milliseconds or frames.
parameter: duration Specifies the duration of the tween, in milliseconds or frames.
returns: percentage complete - between 0.0 and 1.0

    
                  public static function easeOut(timeElapsed:Number, duration:Number):Number
                  {
                          if ((timeElapsed/=duration) < THRESHOLDx1) {
                                  return (BOUNCE_CONST*timeElapsed*timeElapsed);
                          } else if (timeElapsed < THRESHOLDx2) {
                                  return (BOUNCE_CONST*(timeElapsed-=THRESHOLDx15)*timeElapsed + BOUNCE1);
                          } else if (timeElapsed < THRESHOLDx25) {
                                  return (BOUNCE_CONST*(timeElapsed-=THRESHOLDx225)*timeElapsed + BOUNCE2);
                          }
                          return (BOUNCE_CONST*(timeElapsed-=THRESHOLDx2625)*timeElapsed + BOUNCE3);
                  }
          
              

easeInOut combines the motion of easeIn and easeOut by starting out slow and increasing in speed towards the middle of the duration, then slowing down again towards the end. The bouncing will appear to increase then decrease in height.
parameter: timeElapsed Specifies the time since the tween began in milliseconds or frames.
parameter: duration Specifies the duration of the tween, in milliseconds or frames.
parameter: overshoot The ammount to go over past the target value. The higher the number, the farther it will go.
returns: percentage complete - between 0.0 and 1.0

    
                  public static function easeInOut(timeElapsed:Number, duration:Number):Number
                  {
                          if (timeElapsed < duration/2) {
                                  return easeIn (timeElapsed*2, duration)/2;
                          }
                          return easeOut (timeElapsed*2-duration, duration)/2 + 0.5;
                  }
                  
                  

easeOutIn combines the motion of easeIn and easeOut by starting out decelerating towards the middle of the duration, then accelerating end.
parameter: timeElapsed Specifies the time since the tween began in milliseconds or frames.
parameter: duration Specifies the duration of the tween, in milliseconds or frames.
parameter: overshoot The ammount to go over past the target value. The higher the number, the farther it will go.
returns: percentage complete - between 0.0 and 1.0

   
                  public static function easeOutIn (timeElapsed:Number, duration:Number):Number {
                          if (timeElapsed < duration/2) {
                                  return easeOut(timeElapsed*2, duration)/2;
                          }
                          return easeIn((timeElapsed*2)-duration, duration)/2 + 0.5;
                  }
          
          }
  }

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[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

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(C) Æliens 19/08/2009

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