gistfile1.js

	var didScroll = false;
 
	$(window).scroll(function() {
		didScroll = true;
	});

	setInterval(function() {
		if ( didScroll ) {
			didScroll = false;
			
			/*
			if ($(window).scrollTop() > 200) {
				$("body > header").addClass("scrolled");
			} else {
				$("body > header").removeClass("scrolled");
			}
			*/

			if ($("section.projects").visible( true )) {
				var newBgOffset = -930 + (Math.min(0, Math.max(-830, (($("section.projects").offset().top -  $("section.projects").height()) -  ($(window).scrollTop() + 200)- 260)/3)) - 100) * (-1);
				$("section.projects").css("background-position", "center " + newBgOffset + "px");
			}

			if ($(".background .slide").visible( true )) {
				var newBgOffset = Math.max(0, $(window).scrollTop() / 3);
				$(".background .slide img").css("top", newBgOffset+ "px");
			}
		}
	}, 25);