/* =================================================================================================
 * 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.ImagePath       = "transmenu/images/";         // path to menu images (added by jms)
TransMenu.SiteRootPath    = "";							 // root path to site (added by jms)

TransMenu.spacerGif       = "x.gif";                     // transparent spacer gif
TransMenu.dingbatOn       = "submenu-on.gif";            // active sub menu dingbat
TransMenu.dingbatOff      = "submenu-off.gif";           // inactive sub menu dingbat
TransMenu.dingbatSize     = 14;                          // size of the dingbat (square shape assumed)
TransMenu.menuPadding     = 5;                           // padding between menu border and items grid
TransMenu.itemPadding     = 3;                           // additional padding around each item
TransMenu.shadowSize      = 3;                           // size of shadow under menu
TransMenu.shadowOffset    = 2;                           // distance shadow should be offset from leading edge
TransMenu.shadowColor     = "#888";                      // color of shadow (transparency is set in CSS)
TransMenu.shadowPng       = "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   = "white-90.png";              // a PNG graphic to serve as the background for mac IE5
TransMenu.hideDelay       = 300;                         // number of milliseconds to wait before hiding a menu
TransMenu.slideTime       = 300;                         // number of milliseconds it takes to open and close a menu

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


//----------------------------------------------------------------------------------------
// 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) 
	{
        var item = new TransMenuItem(sText, sUrl, this);
        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, -5, 2, 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);

                // 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;
                }
                // safari fix from youngpup transmenu message forum - applied by jms on 03/25/2006
				if (act.tagName == "TR" && act.childNodes[0] && act.childNodes[1] && act.offsetWidth == 0 && act.offsetHeight == 0)
				{
				    switch (iReferencePoint)
				    {
				        case TransMenu.reference.topLeft:
				                break;
				        case TransMenu.reference.topRight:
				                x += act.childNodes[1].offsetLeft + act.childNodes[1].offsetWidth;
				                y += act.childNodes[0].offsetTop;
				                break;
				        case TransMenu.reference.bottomLeft:
				                y += act.childNodes[0].offsetTop + act.childNodes[0].offsetHeight;
				                break;
				        case TransMenu.reference.bottomRight:
				            x += act.childNodes[1].offsetLeft + act.childNodes[1].offsetWidth;
				            y += act.childNodes[0].offsetTop + act.childNodes[0].offsetHeight;
				            break;
				    }
				}
				// end safari fix
                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
                //elmCache["clip"].style.width = ow + TransMenu.shadowSize +  2 + "px";
                //elmCache["clip"].style.height = oh + TransMenu.shadowSize + 2 + "px";
                elmCache["clip"].style.width = ow + "px";
                elmCache["clip"].style.height = oh + "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.ImagePath + 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.ImagePath + 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.ImagePath + 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.ImagePath + TransMenu.dingbatOn);
        }

        function dehighlight(oRow) {
                oRow.className = "item";
                if (childMenus[oRow._index]) 
                        oRow.lastChild.firstChild.src = (TransMenu.ImagePath + 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) 
                                location.href = _this.items[this._index].url;
                }
        }

        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.ImagePath + TransMenu.spacerGif + '" style="border:0;" width="1" height="' + TransMenu.menuPadding + '"></td></tr>' + aHtml.join('') +
                        '<tr><td colspan="2">      <img src="' + TransMenu.ImagePath + TransMenu.spacerGif + '" style="border:0;" width="1" height="' + TransMenu.menuPadding + '"></td></tr></table>' +
                        '<div class="shadowBottom"><img src="' + TransMenu.ImagePath + TransMenu.spacerGif + '" style="border:0;" width="1" height="1"></div>' +
                        '<div class="shadowRight"> <img src="' + TransMenu.ImagePath + TransMenu.spacerGif + '" style="border:0;" width="1" height="1"></div>' +
		        		'<div class="background">  <img src="' + TransMenu.ImagePath + TransMenu.spacerGif + '" style="border:0;" 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) {
        this.toString = toString;
        this.text = sText;
        this.url = sUrl;
        this.parentMenu = oParent;

        function toString(bDingbat) {
                var sDingbat = bDingbat ? (TransMenu.ImagePath + TransMenu.dingbatOff) : (TransMenu.ImagePath + 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;"

                return '<tr class="item"><td nowrap style="' + sPaddingLeft + '">' + 
                        sText + '</td><td width="14" style="' + sPaddingRight + '">' +
                        '<img src="' + sDingbat + '" width="14" height="14" style="border:0;" /></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
if (window.attachEvent) 
{
	var cearElementProps = [
		'data',
		'onmouseover',
		'onmouseout',
		'onmousedown',
		'onmouseup',
		'ondblclick',
		'onclick',
		'onselectstart',
		'oncontextmenu'
	];

	window.attachEvent("onunload", function () 
	{
        var el;
        for (var d = document.all.length; d--; )
		{
            el = document.all[d];
            for (var c = cearElementProps.length; c--; )
			{
                el[cearElementProps[c]] = null;
            }
        }
	});
}