// Ribbon scrolling effects 

// -------------------------------------------------------------------



(function($){



	$.fn.ribbonPosition = function(){

		

		var element = this;

	

		// execute once on load

		changePosition();

		

		// bind function to window scroll event

		$(window).bind("scroll", function(){

			changePosition();

		});

		

		// function to determine position and adjust style

		function changePosition() {

			var	t = $(window).scrollTop();

			var	h = $(window).height();

			

			var	offset = $(window).height() / 25;	// offset - increase or decrease size of middle (set to zero to disable)

			var	zoneSize = $(window).height() / 3;

			var	zoneOne = t + zoneSize + offset;

			var	zoneTwo = t + zoneSize * 2 - offset;

			

			// loop through each element and apply style change

			return $(element).each( function() {

				var obj = $(this);

				var objH = obj.height();

				var offset = obj.offset();

				if (offset.top + objH <= zoneOne) {

					return $(this).css('background-position','0 0');

				} else if (offset.top >= zoneTwo) {

					return $(this).css('background-position','0 -104px');

				} else {

					return $(this).css('background-position','0 -52px');

				}

			});	

		}



	};



})(jQuery);





// load function

jQuery(document).ready(function($) {

	

	// 3D ribbon scroll triggers

	// -------------------------------------------------------------------

	$(".ribbon .wrapAround").ribbonPosition();

	

});