Find the physically closest DOM element

gistfile1.js

(function($){
    $.fn.physicallyClosest = function() {
        var $this = this,
            selector = "body *", 
            options;
        if(typeof arguments[0] === "string") {
            selector = arguments[0];
        }
        else if(typeof arguments[0] === "object") {
            options = arguments[0];
        }
        if(typeof arguments[1] === "object") {
            options = arguments[1];
        }
        var settings = {
            'excludeChildren': false,
            'excludeDescendants': false,
            'reverse': false
        };
        if(options) {
            $.extend(settings, options);
        }
        var selectedY = this.offset().top + (this.height() / 2),
            selectedX = this.offset().left + (this.width() / 2),
            closestFound;
        $(selector).each(function() {
            if(settings.excludeChildren) {
                if($(this).parent().get(0) == $this.get(0)) {
                    return 1;
                }
            }
            if(settings.excludeDescendants) {
                var isDescendant = false;
                $(this).parents().each(function() {
                    if($(this).get(0) == $this.get(0)) {
                        isDescendant = true;
                        return false; //Break
                    }
                });
                if(isDescendant) {
                    return 1; //Continue
                }
            }
            var currentY = $(this).offset().top + ($(this).height() / 2),
                currentX = $(this).offset().left + ($(this).width() / 2),
                yDiff = currentY - selectedY,
                xDiff = currentX - selectedX,
                c = Math.sqrt(Math.pow(xDiff, 2) + Math.pow(yDiff, 2));
            if(closestFound) {
                if(!settings.reverse && c != 0 && c < closestFound.distance) {
                    closestFound = { element: this, distance: c };
                }
                else if(settings.reverse && c != 0 && c > closestFound.distance) {
                    closestFound = { element: this, distance: c };
                }
            }
            else {
                closestFound = { element: this, distance: c };
            }
        });
        return $(closestFound.element);
    };
})(jQuery);