/*
transitions.js

Based on Easing Equations v2.0
(c) 2003 Robert Penner, all rights reserved.
This work is subject to the terms in http://www.robertpenner.com/easing_terms_of_use.html

Adapted for Scriptaculous by Ken Snyder (kendsnyder ~at~ gmail ~dot~ com) June 2006
*/

/*
Overshooting Transitions
*/
// Elastic (adapted from "EaseOutElastic")
Effect.Transitions.Elastic = function(pos) {
  return -1*Math.pow(4,-8*pos) * Math.sin((pos*6-1)*(2*Math.PI)/2) + 1;
};
// SwingFromTo (adapted from "BackEaseInOut")
Effect.Transitions.SwingFromTo = function(pos) {
  var s = 1.70158;
  if ((pos/=0.5) < 1) return 0.5*(pos*pos*(((s*=(1.525))+1)*pos - s));
  return 0.5*((pos-=2)*pos*(((s*=(1.525))+1)*pos + s) + 2);
};
// SwingFrom (adapted from "BackEaseIn")
Effect.Transitions.SwingFrom = function(pos) {
  var s = 1.70158;
  return pos*pos*((s+1)*pos - s);
};
// SwingTo (adapted from "BackEaseOut")
Effect.Transitions.SwingTo = function(pos) {
  var s = 1.70158;
  return (pos-=1)*pos*((s+1)*pos + s) + 1;
};

/*
Bouncing Transitions
*/
// Bounce (adapted from "EaseOutBounce")
Effect.Transitions.Bounce = function(pos) {
  if (pos < (1/2.75)) {
    return (7.5625*pos*pos);
  } else if (pos < (2/2.75)) {
    return (7.5625*(pos-=(1.5/2.75))*pos + .75);
  } else if (pos < (2.5/2.75)) {
    return (7.5625*(pos-=(2.25/2.75))*pos + .9375);
  } else {
    return (7.5625*(pos-=(2.625/2.75))*pos + .984375);
  }
};
// BouncePast (new creation based on "EaseOutBounce")
Effect.Transitions.BouncePast = function(pos) {
  if (pos < (1/2.75)) {
    return (7.5625*pos*pos);
  } else if (pos < (2/2.75)) {
    return 2 - (7.5625*(pos-=(1.5/2.75))*pos + .75);
  } else if (pos < (2.5/2.75)) {
    return 2 - (7.5625*(pos-=(2.25/2.75))*pos + .9375);
  } else {
    return 2 - (7.5625*(pos-=(2.625/2.75))*pos + .984375);
  }
};

/*
Gradual Transitions
*/
// EaseFromTo (adapted from "Quart.EaseInOut")
Effect.Transitions.EaseFromTo = function(pos) {
  if ((pos/=0.5) < 1) return 0.5*Math.pow(pos,4);
  return -0.5 * ((pos-=2)*Math.pow(pos,3) - 2);   
};
// EaseFrom (adapted from "Quart.EaseIn")
Effect.Transitions.EaseFrom = function(pos) {
  return Math.pow(pos,4);
};
// EaseTo (adapted from "Quart.EaseOut")
Effect.Transitions.EaseTo = function(pos) {
  return Math.pow(pos,0.25);
};