/* =================================================================================================
 * TransMenu 
 * March, 2003
 *
 * Customizable multi-level animated DHTML menus with transparency.
 *
 * Copyright 2003-2004, Aaron Boodman (www.youngpup.net)
 * =================================================================================================
 * "Can I use this?"
 * 
 * Use of this library is governed by the Creative Commons Attribution 2.0 License. You can check it 
 * out at: http://creativecommons.org/licenses/by/2.0/
 *
 * Basically: You may copy, distribute, and eat this code as you wish. But you must give me credit 
 * for writing it. You may not misrepresent yourself as the author of this code.
 * =================================================================================================
 * "It's kinda hard to read, though"
 *
 * The uncompressed, commented version of this script can be found at: 
 * http://youngpup.net/projects/transMenus
 * =================================================================================================
 * updates:
 * 04.19.04 fixed cascade problem with menus nested greater than two levels.
 * 12.23.03 added hideCurrent for menu actuators with no menus. renamed to TransMenu.
 * 04.18.03  fixed render bug in IE 5.0 Mac by removing that browser from compatibility table ;)
 *      also made gecko check a little more strict by specifying build no.
 * ============================================================================================== */



//==================================================================================================
// Configuration properties
//==================================================================================================
//==================================================================================================
TransMenu.spacerGif = "../images/x.gif";         // path to a transparent spacer gif
TransMenu.dingbatOn = "../images/arrow-on.gif";      // path to the active sub menu dingbat
TransMenu.dingbatOff = "../images/arrow-off.gif";    // path to the inactive sub menu dingbat
TransMenu.dingbatSize = 8;          // size of the dingbat (square shape assumed)
TransMenu.menuPadding = 0;           // padding between menu border and items grid
TransMenu.itemPadding = 5;           // additional padding around each item
TransMenu.shadowSize = 2;            // size of shadow under menu
TransMenu.shadowOffset = 3;          // distance shadow should be offset from leading edge
TransMenu.shadowColor = "#888";      // color of shadow (transparency is set in CSS)
TransMenu.shadowPng = "images/grey-40.png";         // a PNG graphic to serve as the shadow for mac IE5
TransMenu.backgroundColor = "#000000";       // color of the background (transparency set in CSS)
TransMenu.backgroundPng = "images/white-90.png";    // a PNG graphic to server as the background for mac IE5
TransMenu.hideDelay = 1000;          // number of milliseconds to wait before hiding a menu
TransMenu.slideTime = 500;           // number of milliseconds it takes to open and close a menu
TransMenu.subpad_x = 0;                   // Horizontal Padding between top right corner of item menu and its submenu (level > 2)
TransMenu.subpad_y = -2;                 // Vertical Padding between top right corner of item menu and its submenu (level > 2)

//==================================================================================================
// Internal use properties
//==================================================================================================
TransMenu.reference = {topLeft:1,topRight:2,bottomLeft:3,bottomRight:4};
TransMenu.direction = {down:1,right:2};
TransMenu.registry = [];
TransMenu._maxZ = 100;

TransMenu.updateImgPath = function (imgPath){
  TransMenu.spacerGif = imgPath + TransMenu.spacerGif;
  TransMenu.dingbatOn = imgPath + TransMenu.dingbatOn;
  TransMenu.dingbatOff = imgPath + TransMenu.dingbatOff;
  TransMenu.shadowPng = imgPath + TransMenu.shadowPng;
  TransMenu.backgroundPng = imgPath + TransMenu.backgroundPng;
}

//==================================================================================================
// Static methods
//==================================================================================================
// supporting win ie5+, mac ie5.1+ and gecko >= mozilla 1.0
TransMenu.isSupported = function() {
  var ua = navigator.userAgent.toLowerCase();
    var pf = navigator.platform.toLowerCase();
  var an = navigator.appName;
  var r = false;

  if (ua.indexOf("gecko") > -1 && navigator.productSub >= 20020605) r = true; // gecko >= moz 1.0
  else if (an == "Microsoft Internet Explorer") {
    if (document.getElementById) { // ie5.1+ mac,win
      if (pf.indexOf("mac") == 0) {
              r = /msie (\d(.\d*)?)/.test(ua) && Number(RegExp.$1) >= 5.1;
            }
            else r = true;
    }
  }

  return r;
}

// call this in onload once menus have been created
TransMenu.initialize = function() {
  for (var i = 0, menu = null; menu = this.registry[i]; i++) {
    menu.initialize();
  }
}

// call this in document body to write out menu html
TransMenu.renderAll = function() {
  var aMenuHtml = [];
  for (var i = 0, menu = null; menu = this.registry[i]; i++) {
    aMenuHtml[i] = menu.toString();
  }
  document.write(aMenuHtml.join(""));
}

//==================================================================================================
// TransMenu constructor (only called internally)
//==================================================================================================
// oActuator      : The thing that causes the menu to be shown when it is mousedover. Either a
//      reference to an HTML element, or a TransMenuItem from an existing menu.
// iDirection     : The direction to slide out. One of TransMenu.direction.
// iLeft    : Left pixel offset of menu from actuator
// iTop     : Top pixel offset of menu from actuator
// iReferencePoint      : Corner of actuator to measure from. One of TransMenu.referencePoint.
// parentMenuSet  : Menuset this menu will be added to.
//==================================================================================================
function TransMenu(oActuator, iDirection, iLeft, iTop, iReferencePoint, parentMenuSet) {
  // public methods
  this.addItem = addItem;
  this.addMenu = addMenu;
  this.toString = toString;
  this.initialize = initialize;
  this.isOpen = false;
  this.show = show;
  this.hide = hide;
  this.items = [];

  // events
  this.onactivate = new Function();       // when the menu starts to slide open
  this.ondeactivate = new Function();     // when the menu finishes sliding closed
  this.onmouseover = new Function();      // when the menu has been moused over
  this.onqueue = new Function();    // hack .. when the menu sets a timer to be closed a little while in the future
    this.ondequeue = new Function();

  // initialization
  this.index = TransMenu.registry.length;
  TransMenu.registry[this.index] = this;

  var id = "TransMenu" + this.index;
  var contentHeight = null;
  var contentWidth = null;
  var childMenuSet = null;
  var animating = false;
  var childMenus = [];
  var slideAccel = -1;
  var elmCache = null;
  var ready = false;
  var _this = this;
  var a = null;

  var pos = iDirection == TransMenu.direction.down ? "top" : "left";
  var dim = null;

  // private and public method implimentations
  function addItem(sText, sUrl, browserNav, active) {
    var item = new TransMenuItem(sText, sUrl, this, browserNav, active);
    item._index = this.items.length;
    this.items[item._index] = item;
  }

  function addMenu(oMenuItem) {
    if (!oMenuItem.parentMenu == this) throw new Error("Cannot add a menu here");

    if (childMenuSet == null) childMenuSet = new TransMenuSet(TransMenu.direction.right, TransMenu.subpad_x, TransMenu.subpad_y, TransMenu.reference.topRight);

    var m = childMenuSet.addMenu(oMenuItem);

    childMenus[oMenuItem._index] = m;
    m.onmouseover = child_mouseover;
    m.ondeactivate = child_deactivate;
    m.onqueue = child_queue;
        m.ondequeue = child_dequeue;

    return m;
  }

  function initialize() {
    initCache();
    initEvents();
    initSize();
    ready = true;
  }

  function show() {
    //dbg_dump("show");
    if (ready) {
      _this.isOpen = true;
      animating = true;
      setContainerPos();
      elmCache["clip"].style.visibility = "visible";
      elmCache["clip"].style.zIndex = TransMenu._maxZ++;
      //dbg_dump("maxZ: " + TransMenu._maxZ);
      slideStart();
      _this.onactivate();
    }
  }

  function hide() {
    if (ready) {
      _this.isOpen = false;
      animating = true;

      for (var i = 0, item = null; item = elmCache.item[i]; i++) 
        dehighlight(item);

      if (childMenuSet) childMenuSet.hide();

      slideStart();
      _this.ondeactivate();
    }
  }

  function setContainerPos() {
    var sub = oActuator.constructor == TransMenuItem; 
    var act = sub ? oActuator.parentMenu.elmCache["item"][oActuator._index] : oActuator; 
    var el = act;
    
    var x = 0;
    var y = 0;

    
    var minX = 0;
    var maxX = (window.innerWidth ? window.innerWidth : document.body.clientWidth) - parseInt(elmCache["clip"].style.width);
    var minY = 0;
    var maxY = (window.innerHeight ? window.innerHeight : document.body.clientHeight) - parseInt(elmCache["clip"].style.height);
	maxX = 10000;
	maxY = 10000;

    // add up all offsets... subtract any scroll offset
    while (sub ? el.parentNode.className.indexOf("transMenu") == -1 : el.offsetParent) {
      x += el.offsetLeft;
      y += el.offsetTop;

	  if (el.scrollLeft) x -= el.scrollLeft;
      if (el.scrollTop) y -= el.scrollTop;
      
      el = el.offsetParent;
    }

    if (oActuator.constructor == TransMenuItem) {
      x += parseInt(el.parentNode.style.left);
      y += parseInt(el.parentNode.style.top);
    }

    switch (iReferencePoint) {
      case TransMenu.reference.topLeft:
        break;
      case TransMenu.reference.topRight:
        x += act.offsetWidth;
        break;
      case TransMenu.reference.bottomLeft:
        y += act.offsetHeight;
        break;
      case TransMenu.reference.bottomRight:
        x += act.offsetWidth;
        y += act.offsetHeight;
        break;
    }

    x += iLeft;
    y += iTop;

	x = Math.max(Math.min(x, maxX), minX);
    y = Math.max(Math.min(y, maxY), minY);

    elmCache["clip"].style.left = x + "px";
    elmCache["clip"].style.top = y + "px";
  }

  function slideStart() {
    var x0 = parseInt(elmCache["content"].style[pos]);
    var x1 = _this.isOpen ? 0 : -dim;

    if (a != null) a.stop();
    a = new Accelimation(x0, x1, TransMenu.slideTime, slideAccel);

    a.onframe = slideFrame;
    a.onend = slideEnd;

    a.start();
  }

  function slideFrame(x) {
    elmCache["content"].style[pos] = x + "px";
  }

  function slideEnd() {
    if (!_this.isOpen) elmCache["clip"].style.visibility = "hidden";
    animating = false;
  }

  function initSize() {
    // everything is based off the size of the items table...
    var ow = elmCache["items"].offsetWidth;
    var oh = elmCache["items"].offsetHeight;
    var ua = navigator.userAgent.toLowerCase();

	// clipping container should be ow/oh + the size of the shadow
	//[radek]
    elmCache["clip"].style.textAlign = "left";
	elmCache["clip"].style.width = 00 + ow + TransMenu.shadowSize +  2 + "px";
    elmCache["clip"].style.height = oh + TransMenu.shadowSize + 2 + "px";

    // same with content...
    elmCache["content"].style.width = ow + TransMenu.shadowSize + "px";
    elmCache["content"].style.height = oh + TransMenu.shadowSize + "px";

    contentHeight = oh + TransMenu.shadowSize;
    contentWidth = ow + TransMenu.shadowSize;
    
    dim = iDirection == TransMenu.direction.down ? contentHeight : contentWidth;

    // set initially closed
    elmCache["content"].style[pos] = -dim - TransMenu.shadowSize + "px";
    elmCache["clip"].style.visibility = "hidden";

    // if *not* mac/ie 5
    if (ua.indexOf("mac") == -1 || ua.indexOf("gecko") > -1) {
      // set background div to offset size
      elmCache["background"].style.width = ow + "px";
      elmCache["background"].style.height = oh + "px";
      elmCache["background"].style.backgroundColor = TransMenu.backgroundColor;

      // shadow left starts at offset left and is offsetHeight pixels high
      elmCache["shadowRight"].style.left = ow + "px";
      elmCache["shadowRight"].style.height = oh - (TransMenu.shadowOffset - TransMenu.shadowSize) + "px";
      elmCache["shadowRight"].style.backgroundColor = TransMenu.shadowColor;

      // shadow bottom starts at offset height and is offsetWidth - shadowOffset 
      // pixels wide (we don't want the bottom and right shadows to overlap or we 
      // get an extra bright bottom-right corner)
      elmCache["shadowBottom"].style.top = oh + "px";
      elmCache["shadowBottom"].style.width = ow - TransMenu.shadowOffset + "px";
      elmCache["shadowBottom"].style.backgroundColor = TransMenu.shadowColor;
    }
    // mac ie is a little different because we use a PNG for the transparency
    else {
      // set background div to offset size
      elmCache["background"].firstChild.src = TransMenu.backgroundPng;
      elmCache["background"].firstChild.width = ow;
      elmCache["background"].firstChild.height = oh;

      // shadow left starts at offset left and is offsetHeight pixels high
      elmCache["shadowRight"].firstChild.src = TransMenu.shadowPng;
      elmCache["shadowRight"].style.left = ow + "px";
      elmCache["shadowRight"].firstChild.width = TransMenu.shadowSize;
      elmCache["shadowRight"].firstChild.height = oh - (TransMenu.shadowOffset - TransMenu.shadowSize);

      // shadow bottom starts at offset height and is offsetWidth - shadowOffset 
      // pixels wide (we don't want the bottom and right shadows to overlap or we 
      // get an extra bright bottom-right corner)
      elmCache["shadowBottom"].firstChild.src = TransMenu.shadowPng;
      elmCache["shadowBottom"].style.top = oh + "px";
      elmCache["shadowBottom"].firstChild.height = TransMenu.shadowSize;
      elmCache["shadowBottom"].firstChild.width = ow - TransMenu.shadowOffset;
    }
  }
  
  function initCache() {
    var menu = document.getElementById(id);
    var all = menu.all ? menu.all : menu.getElementsByTagName("*"); // IE/win doesn't support * syntax, but does have the document.all thing

    elmCache = {};
    elmCache["clip"] = menu;
    elmCache["item"] = [];
    
    for (var i = 0, elm = null; elm = all[i]; i++) {
      switch (elm.className) {
        case "items":
        case "content":
        case "background":
        case "shadowRight":
        case "shadowBottom":
          elmCache[elm.className] = elm;
          break;
        case "item":
          elm._index = elmCache["item"].length;
          elmCache["item"][elm._index] = elm;
          break;
      }
    }

    // hack!
    _this.elmCache = elmCache;
  }

  function initEvents() {
    // hook item mouseover
    for (var i = 0, item = null; item = elmCache.item[i]; i++) {
      item.onmouseover = item_mouseover;
      item.onmouseout = item_mouseout;
      item.onclick = item_click;
    }

    // hook actuation
    if (typeof oActuator.tagName != "undefined") {
      oActuator.onmouseover = actuator_mouseover;
      oActuator.onmouseout = actuator_mouseout;
    }

    // hook menu mouseover
    elmCache["content"].onmouseover = content_mouseover;
    elmCache["content"].onmouseout = content_mouseout;
  }

  function highlight(oRow) {
    oRow.className = "item hover";
    if (childMenus[oRow._index]) 
      oRow.lastChild.firstChild.src = TransMenu.dingbatOn;
  }

  function dehighlight(oRow) {
    oRow.className = "item";
    if (childMenus[oRow._index]) 
      oRow.lastChild.firstChild.src = TransMenu.dingbatOff;
  }

  function item_mouseover() {
    if (!animating) {
      highlight(this);

      if (childMenus[this._index]) 
        childMenuSet.showMenu(childMenus[this._index]);
      else if (childMenuSet) childMenuSet.hide();
    }
  }

  function item_mouseout() {
    if (!animating) {
      if (childMenus[this._index])
        childMenuSet.hideMenu(childMenus[this._index]);
      else    // otherwise child_deactivate will do this
        dehighlight(this);
    }
  }

  function item_click() {
    if (!animating) {
      if (_this.items[this._index].url) {
              switch (_this.items[this._index].browserNav) {
                // cases are slightly different
                case 1:
                // open in a new window
                window.open(_this.items[this._index].url, '', '');;
                  
                break;

                case 2:
                // open in a popup window
                window.open(_this.items[this._index].url, '', 'toolbar=no,location=no,status=no,menubar=no,scrollbars=yes,resizable=yes,width=780,height=550');;
                break;

                case 3:
                // don't link it
                break;

                default:  // formerly case 2
                // open in parent window
                location.href = _this.items[this._index].url;
                break;
              }
            }
    }
  }

  function actuator_mouseover() {
    parentMenuSet.showMenu(_this);
  }

  function actuator_mouseout() {
    parentMenuSet.hideMenu(_this);
  }

  function content_mouseover() {
    if (!animating) {
      parentMenuSet.showMenu(_this);
      _this.onmouseover();
    }
  }

  function content_mouseout() {
    if (!animating) {
      parentMenuSet.hideMenu(_this);
    }
  }

  function child_mouseover() {
    if (!animating) {
      parentMenuSet.showMenu(_this);
    }
  }

  function child_deactivate() {
    for (var i = 0; i < childMenus.length; i++) {
      if (childMenus[i] == this) {
        dehighlight(elmCache["item"][i]);
        break;
      }
    }
  }

  function child_queue() {
    parentMenuSet.hideMenu(_this);
  }

    function child_dequeue() {
        parentMenuSet.showMenu(_this);
    }

  function toString() {
    var aHtml = [];
    var sClassName = "transMenu" + (oActuator.constructor != TransMenuItem ? " top" : "");

    for (var i = 0, item = null; item = this.items[i]; i++) {
      aHtml[i] = item.toString(childMenus[i]);
    }

    return '<div id="' + id + '" class="' + sClassName + '">' + 
      '<div class="content"><table class="items" cellpadding="0" cellspacing="0" border="0">' + 
      '<tr><td colspan="2"><img src="' + TransMenu.spacerGif + '" width="1" height="' + TransMenu.menuPadding + '"></td></tr>' + 
      aHtml.join('') + 
      '<tr><td colspan="2"><img src="' + TransMenu.spacerGif + '" width="1" height="' + TransMenu.menuPadding + '"></td></tr></table>' + 
      '<div class="shadowBottom"><img src="' + TransMenu.spacerGif + '" width="1" height="1"></div>' + 
      '<div class="shadowRight"><img src="' + TransMenu.spacerGif + '" width="1" height="1"></div>' + 
      '<div class="background"><img src="' + TransMenu.spacerGif + '" width="1" height="1"></div>' + 
      '</div></div>';
  }
}


//==================================================================================================
// TransMenuSet
//==================================================================================================
// iDirection     : The direction to slide out. One of TransMenu.direction.
// iLeft    : Left pixel offset of menus from actuator
// iTop     : Top pixel offset of menus from actuator
// iReferencePoint      : Corner of actuator to measure from. One of TransMenu.referencePoint.
//==================================================================================================
TransMenuSet.registry = [];

function TransMenuSet(iDirection, iLeft, iTop, iReferencePoint) {
  // public methods
  this.addMenu = addMenu;
  this.showMenu = showMenu;
  this.hideMenu = hideMenu;
  this.hide = hide;
  this.hideCurrent = hideCurrent;

  // initialization
  var menus = [];
  var _this = this;
  var current = null;

  this.index = TransMenuSet.registry.length;
  TransMenuSet.registry[this.index] = this;

  // method implimentations...
  function addMenu(oActuator) {
    var m = new TransMenu(oActuator, iDirection, iLeft, iTop, iReferencePoint, this);
    menus[menus.length] = m;
    return m;
  }

  function showMenu(oMenu) {
    if (oMenu != current) {
      // close currently open menu
      if (current != null) hide(current);  

      // set current menu to this one
      current = oMenu;

      // if this menu is closed, open it
      oMenu.show();
    }
    else {
      // hide pending calls to close this menu
      cancelHide(oMenu);
    }
  }

  function hideMenu(oMenu) {
    //dbg_dump("hideMenu a " + oMenu.index);
    if (current == oMenu && oMenu.isOpen) {
      //dbg_dump("hideMenu b " + oMenu.index);
      if (!oMenu.hideTimer) scheduleHide(oMenu);
    }
  }

  function scheduleHide(oMenu) {
    //dbg_dump("scheduleHide " + oMenu.index);
    oMenu.onqueue();
    oMenu.hideTimer = window.setTimeout("TransMenuSet.registry[" + _this.index + "].hide(TransMenu.registry[" + oMenu.index + "])", TransMenu.hideDelay);
  }

  function cancelHide(oMenu) {
    //dbg_dump("cancelHide " + oMenu.index);
    if (oMenu.hideTimer) {
            oMenu.ondequeue();
      window.clearTimeout(oMenu.hideTimer);
      oMenu.hideTimer = null;
    }
  }

  function hide(oMenu) {   
    if (!oMenu && current) oMenu = current;

    if (oMenu && current == oMenu && oMenu.isOpen) {
      hideCurrent();
    }
  }

  function hideCurrent() {
        if (null != current) {
          cancelHide(current);
          current.hideTimer = null;
          current.hide();
          current = null;
        }
  }
}

//==================================================================================================
// TransMenuItem (internal)
// represents an item in a dropdown
//==================================================================================================
// sText  : The item display text
// sUrl   : URL to load when the item is clicked
// oParent      : Menu this item is a part of
//==================================================================================================
function TransMenuItem(sText, sUrl, oParent, browserNav, active) {
  this.toString = toString;
  this.text = sText;
  this.url = sUrl;
    this.browserNav = browserNav;
  this.parentMenu = oParent;
    this.active = active;

  function toString(bDingbat) {
    var sDingbat = bDingbat ? TransMenu.dingbatOff : TransMenu.spacerGif;
    var iEdgePadding = TransMenu.itemPadding + TransMenu.menuPadding;
    var sPaddingLeft = "padding:" + TransMenu.itemPadding + "px; padding-left:" + iEdgePadding + "px;"
    var sPaddingRight = "padding:" + TransMenu.itemPadding + "px; padding-right:" + iEdgePadding + "px;"
        var id = active?' id="active" ':'';
          /*return '<tr class="item"'+id+'><td nowrap style="' + sPaddingLeft + sPaddingRight + '"><div style="background: url(' + sDingbat + ') right no-repeat;">' + 
      sText + '</div></td></tr>';*/
    return '<tr class="item"'+id+'><td nowrap style="' + sPaddingLeft + '">' + 
      sText + '</td><td width="10" style="' + sPaddingRight + '">' + 
      '<img src="' + sDingbat + '" width="8" height="8"></td></tr>';
  }
}

//=====================================================================
// Accel[erated] [an]imation object
// change a property of an object over time in an accelerated fashion
//=====================================================================
// obj  : reference to the object whose property you'd like to animate
// prop : property you would like to change eg: "left"
// to   : final value of prop
// time : time the animation should take to run
// zip  : optional. specify the zippiness of the acceleration. pick a 
//      number between -1 and 1 where -1 is full decelerated, 1 is 
//      full accelerated, and 0 is linear (no acceleration). default
//      is 0.
// unit  : optional. specify the units for use with prop. default is 
//      "px".
//=====================================================================
// bezier functions lifted from the lib_animation.js file in the 
// 13th Parallel API. www.13thparallel.org
//=====================================================================

function Accelimation(from, to, time, zip) {
  if (typeof zip  == "undefined") zip  = 0;
  if (typeof unit == "undefined") unit = "px";

  this.x0   = from;
  this.x1    = to;
  this.dt    = time;
  this.zip  = -zip;
  this.unit  = unit;
  this.timer  = null;
  this.onend  = new Function();
  this.onframe    = new Function();
}



//=====================================================================
// public methods
//=====================================================================

// after you create an accelimation, you call this to start it-a runnin'
Accelimation.prototype.start = function() {
  this.t0 = new Date().getTime();
  this.t1 = this.t0 + this.dt;
  var dx  = this.x1 - this.x0;
  this.c1 = this.x0 + ((1 + this.zip) * dx / 3);
  this.c2 = this.x0 + ((2 + this.zip) * dx / 3);
  Accelimation._add(this);
}

// and if you need to stop it early for some reason...
Accelimation.prototype.stop = function() {
  Accelimation._remove(this);
}



//=====================================================================
// private methods
//=====================================================================

// paints one frame. gets called by Accelimation._paintAll.
Accelimation.prototype._paint = function(time) {
  if (time < this.t1) {
    var elapsed = time - this.t0;
    this.onframe(Accelimation._getBezier(elapsed/this.dt,this.x0,this.x1,this.c1,this.c2));
  }
  else this._end();
}

// ends the animation
Accelimation.prototype._end = function() {
  Accelimation._remove(this);
  this.onframe(this.x1);
  this.onend();
}




//=====================================================================
// static methods (all private)
//=====================================================================

// add a function to the list of ones to call periodically
Accelimation._add = function(o) {
  var index = this.instances.length;
  this.instances[index] = o;
  // if this is the first one, start the engine
  if (this.instances.length == 1) {
    this.timerID = window.setInterval("Accelimation._paintAll()", this.targetRes);
  }
}

// remove a function from the list
Accelimation._remove = function(o) {
  for (var i = 0; i < this.instances.length; i++) {
    if (o == this.instances[i]) {
      this.instances = this.instances.slice(0,i).concat( this.instances.slice(i+1) );
      break;
    }
  }
  // if that was the last one, stop the engine
  if (this.instances.length == 0) {
    window.clearInterval(this.timerID);
    this.timerID = null;
  }
}

// "engine" - call each function in the list every so often
Accelimation._paintAll = function() {
  var now = new Date().getTime();
  for (var i = 0; i < this.instances.length; i++) {
    this.instances[i]._paint(now);
  }
}


// Bezier functions:
Accelimation._B1 = function(t) { return t*t*t }
Accelimation._B2 = function(t) { return 3*t*t*(1-t) }
Accelimation._B3 = function(t) { return 3*t*(1-t)*(1-t) }
Accelimation._B4 = function(t) { return (1-t)*(1-t)*(1-t) }


//Finds the coordinates of a point at a certain stage through a bezier curve
Accelimation._getBezier = function(percent,startPos,endPos,control1,control2) {
  return endPos * this._B1(percent) + control2 * this._B2(percent) + control1 * this._B3(percent) + startPos * this._B4(percent);
}


//=====================================================================
// static properties
//=====================================================================

Accelimation.instances = [];
Accelimation.targetRes = 10;
Accelimation.timerID = null;


//=====================================================================
// IE win memory cleanup
//=====================================================================

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    'data',
    'onmouseover',
    'onmouseout',
    'onmousedown',
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    'onclick',
    'onselectstart',
    'oncontextmenu'
  ];

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