Cycle 2 BG lookahead plugin

gistfile1.js

/*! Cycle2 lookahead plugin for backgrounds
 * Copyright (c) 2013 M. Alsup; Dual licensed: MIT/GPL
 * @author Jeff Turcotte <jeff@imarc.net>
 */
(function($) {
  "use strict";

	$(document).on( 'cycle-initialized', function(e, opts) {
		var key = 'cycle-look-ahead';

		opts.container.on( 'cycle-before', function( e, opts, outgoing, incoming, fwd ) {
			var index = fwd ? (opts.nextSlide + 1) : (opts.nextSlide - 1),
			slide = $( opts.slides[ index ] ),
			images;

		if ( slide.length && ! slide.data( key ) ) {
			slide.data( key, true );

			backgrounds = slide.find('[data-cycle-bg]');

			if (slide.is('[data-cycle-bg]')) {
				backgrounds.add(slide); 
			}

			backgrounds.each(function() {
				var elem = $(this);
				elem.css('background-image', elem.attr('data-cycle-bg'));
				elem.removeAttr( 'data-cycle-bg' );
			});
		}
		});
	});
})(jQuery);