Get dimensions from a hidden DOM element

gistfile1.js

$.fn.getHiddenDimensions = function(includeMargin) {
	var $item = this,
		props = { position: 'absolute', visibility: 'hidden', display: 'block' },
		dim = { width:0, height:0, innerWidth: 0, innerHeight: 0, outerWidth: 0, outerHeight: 0 },
		$hiddenParents = $item.parents().andSelf().not(':visible'),
		includeMargin = (includeMargin == null)? false : includeMargin;

	var oldProps = [];
	$hiddenParents.each(function() {
		var old = {};

		for ( var name in props ) {
			old[ name ] = this.style[ name ];
			this.style[ name ] = props[ name ];
		}

		oldProps.push(old);
	});

	dim.width = $item.width();
	dim.outerWidth = $item.outerWidth(includeMargin);
	dim.innerWidth = $item.innerWidth();
	dim.height = $item.height();
	dim.innerHeight = $item.innerHeight();
	dim.outerHeight = $item.outerHeight(includeMargin);
	dim.offset = $item.offset();

	$hiddenParents.each(function(i) {
		var old = oldProps[i];
		for ( var name in props ) {
			this.style[ name ] = old[ name ];
		}
	});

	return dim;
};