package org.as3lib.kitchensync.easing
  {
          

<p>@ax-lib-flex-animation-code-10-org-as3lib-kitchensync-easing-Oscillate is slightly different from the other easing classes. The functions in this class cause motion that oscillates at a specified frequency based on the timeElapsed. The values will continue to oscilate between 0.0 and 1.0 without reaching an end point. However, if <code>snapping</code> is set to true, the functions will return a 1.0 when the duration has elapsed.</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: Mims H. Wright
see: EasingUtil

  
          public class @ax-lib-flex-animation-code-10-org-as3lib-kitchensync-easing-Oscillate
          {
                  private static const TWICE_PI:Number = Math.PI*2;
                  public static var defaultFrequency:Number = 1; // in hertz, that's 1 cycle every 1 second
                  public static var defaultPulseWidth:Number = 0.5; // Square Wave
                  
                  public static var snapping:Boolean = false;
                  
                  

@files between 0 and 1.0 (starting with 0 and ending with 1.0) for as long as the duration lasts in a sinusoidal motion. The position will be based on the timeElapsed and frequency.
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: frequency - The frequency of the sine wave in hertz. Higher is faster. 1/frequency = wavelength
returns: Number - between 0.0 and 1.0 based on the time and frequency. Returns 1.0 if duration is elapsed and snapping is turned on.

    
                  public static function sine(timeElapsed:Number, duration:Number, frequency:Number = NaN):Number {
                          if (isNaN(frequency)) { frequency = defaultFrequency; }
                          if (timeElapsed >= duration && snapping == true) { return 1.0 }
                          frequency /= 1000;
                          return 0.5 * (1 - Math.cos( TWICE_PI * timeElapsed * frequency));
                  }        
  
                  

@files between 0 and 1.0 (starting with 0 and ending with 1.0) for as long as the duration lasts in an absolute sinusoidal (half-wave) motion. The subject will appear to be bouncing. The position will be based on the timeElapsed and frequency.
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: frequency - The frequency of the sine wave in hertz. Higher is faster. 1/frequency = wavelength
returns: Number - between 0.0 and 1.0 based on the time and frequency. Returns 1.0 if duration is elapsed and snapping is turned on.

    
                  public static function absoluteSine(timeElapsed:Number, duration:Number, frequency:Number=NaN):Number {
                          if (isNaN(frequency)) { frequency = defaultFrequency; }
                          if (timeElapsed >= duration && snapping == true) { return 1.0 }
                          frequency /= 1000;
                          return Math.abs(Math.cos( TWICE_PI * timeElapsed * frequency));
                  }        
          
                  

@files between 0 and 1.0 (starting with 0 and ending with 1.0) for as long as the duration lasts in linear motion. The position will be based on the timeElapsed and frequency.
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: frequency - The frequency of the sine wave in hertz. Higher is faster. 1/frequency = wavelength
returns: Number - between 0.0 and 1.0 based on the time and frequency. Returns 1.0 if duration is elapsed and snapping is turned on.

    
                  public static function sawtooth(timeElapsed:Number, duration:Number, frequency:Number=NaN):Number {
                          if (isNaN(frequency)) { frequency = defaultFrequency; }
                          if (timeElapsed >= duration && snapping == true) { return 1.0 }
                          frequency /= 1000;
                          return timeElapsed * frequency % 1.0;
                  }        
                  
                  

@files between 0 and 1.0 (starting with 0 and ending with 1.0) for as long as the duration lasts in linear motion. The position will be based on the timeElapsed and frequency.
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: frequency - The frequency of the sine wave in hertz. Higher is faster. 1/frequency = wavelength
returns: Number - between 0.0 and 1.0 based on the time and frequency. Returns 1.0 if duration is elapsed and snapping is turned on.

    
                  public static function triangle(timeElapsed:Number, duration:Number, frequency:Number = NaN):Number {
                          if (isNaN(frequency)) { frequency = defaultFrequency; }
                          if (timeElapsed >= duration && snapping == true) { return 1.0 }
                          frequency /= 1000;
                          var position:Number = timeElapsed * frequency;
                          if (position % 2.0 >= 1.0) { return 1.0 - (position % 1.0); }
                          return position % 1.0;
                  }        
  
                  

@files between 0 and 1.0 (starting with 0 and ending with 1.0) for as long as the duration lasts in square or pulse wave motion. The subject will appear to alternate between the start and end points. The position will be based on the timeElapsed and frequency.
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: frequency - The frequency of the sine wave in hertz. Higher is faster. 1/frequency = wavelength
parameter: pulseWidth - The width of the upside of the square wave as a percentage. 0.5 is half up, half down. 0.0 is all down, 1.0 is all up.
returns: Number - between 0.0 and 1.0 based on the time and frequency. Returns 1.0 if duration is elapsed and snapping is turned on.

    
                  public static function pulse(timeElapsed:Number, duration:Number, frequency:Number = NaN, pulseWidth:Number= NaN):Number {
                          if (isNaN(frequency)) { frequency = defaultFrequency; }
                          if (isNaN(pulseWidth)) { pulseWidth = defaultPulseWidth; }
                          frequency /= 1000;
                          if (timeElapsed >= duration && snapping == true) { return 1.0 }
                          if ((timeElapsed * frequency % 1.0) >= pulseWidth) { return 1.0 }
                          return 0;
                  }        
          }
  }

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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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