jQuery on window scroll animate background image position

Question

I am trying to achieve a scrolling effect using jQuery. I have a background div set to 100% browser window size with overflow hidden. This has a large background image that

Answer 1

If you don't want to be hassled with the extra background div, here's my code I wrapped up from several examples:

$(window).scroll(function () {
    setBackgroundPosition();
})
$(window).resize(function() {
    setBackgroundPosition();
});
function setBackgroundPosition(){
    $("body").css('background-position', "-" + (1920 - $(window).width()) / 2 + "px " + -(Math.max(document.body.scrollTop, document.documentElement.scrollTop) / 4) + "px");
}

The Math.max is required for cross-browser issues. Also replace '1920' with the width of your background image

body{
    background-image:url(images/background.jpg);
    background-position:center top;
    background-repeat:no-repeat;
    background-attachment:fixed;
}