/***
@title:
Fixed Center

@version:
1.3

@author:
David Tang

@date:
2010-12-06 - performance issues update
2010-06-27 - updated plugin to use fixed positioning instead of absolute
2010-06-17 - released version 1 of the plugin

@url
www.david-tang.net

@copyright:
2010 David Tang

@requires:
jquery

@does:
This plugin centers an element on the page using fixed positioning and keeps the element centered 
if you scroll horizontally or vertically.

@howto:
jQuery('#my-element').fixedCenter(); would center the element with ID 'my-element' using absolute positioning 

*/  
(function(){
    jQuery.fn.fixedCenter = function(){
        return this.each(function(){
            var element = jQuery(this), win = jQuery(window);
            centerElement();
            
            jQuery(window).bind('resize',function(){
                centerElement();
            });

            function centerElement(){
                var elementWidth, elementHeight, windowWidth, windowHeight, X2, Y2;
                elementWidth = element.outerWidth();
                elementHeight = element.outerHeight();
                windowWidth = win.width();
                windowHeight = win.height();    
                X2 = (windowWidth/2 - elementWidth/2) + "px";
                Y2 = (windowHeight/2 - elementHeight/2) + "px";
                jQuery(element).css({
                    'left':X2,
                    'top':Y2,
                    'position':'fixed'
                });                        
            } //centerElement function
        });
    }
})();