/* =================================================================================================

 * 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 = "img/x.gif";                     // path to a transparent spacer gif

TransMenu.dingbatOn = "img/arrowchild.gif";            // path to the active sub menu dingbat

TransMenu.dingbatOff = "img/arrowchild.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 = "#999999";                        // color of shadow (transparency is set in CSS)

TransMenu.shadowPng = "img/grey-40.png";               // a PNG graphic to serve as the shadow for mac IE5

TransMenu.backgroundColor = "#1F1F1F";                   // color of the background (transparency set in CSS)

TransMenu.backgroundPng = "img/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 = 400;                             // 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();

                        

                        if (!oActuator.parentMenu) {

                        	oActuator.className = oActuator.className.replace(/ jahover-active/, '');

                        	oActuator.className = oActuator.className.replace(/ jahover/, '');

                        }

                }

        }



        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

                elmCache["clip"].style.width = 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);

                if (!oActuator.parentMenu) {

                	if (oActuator.className.indexOf(' jahover') < 0){

                		if (oActuator.className.indexOf('-active') < 0)

                			oActuator.className += ' jahover';

                		else

                			oActuator.className += ' jahover-active';              			

                	}

                }

        }



        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

//=====================================================================



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;

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        }

	});

}