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 is approx. 1500px x 2000px.

The effect I want is when the user scrolls down the page the background image moves at a percentage of the scrolled distance, so for every 200px scrolled down the page the image moves 10px in the same direction.

Can anyone point me in the right direction? Is this even possible? : ) Many thanks in advance.

UPDATE

I have since tried variations on the suggestion by @Capt Otis but I'm still struggling the code I am playing around with is as follows:

$(window).scroll(function(){
    if($(this).scrollTop() > 200) {
        $('#div').animate({'background-postion': '+=10px 0'}, 500);
    }
});     

Can anyone shed any light on what I am doing wrong?

Solution 1

Here you go. Background is set to 10% scroll. You can change the background scroll rate by changing the 10 in the code.

CSS

html, body{
    height:100%;
    min-height:100%;
    margin:0;
    padding:0;
}
.bg{
    width:100%;
    height:100%;
    background: #fff url(..) no-repeat fixed 0 0;
    overflow:auto;
}

<div class="bg">
   <span>..</span>
</div>

JavaScript

$('.bg').scroll(function() {
    var x = $(this).scrollTop();
    $(this).css('background-position', '0% ' + parseInt(-x / 10) + 'px');
});

Check working example at http://jsfiddle.net/Vbtts/
Click this link for the full screen example: http://jsfiddle.net/Vbtts/embedded/result/

---

Solution 2

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;
}

Solution 3

This worked for me:

In js:

$(window).scroll(function() {
    var x = $(this).scrollTop();
    $('#main').css('background-position', '100% ' + parseInt(-x / 1) + 'px' + ', 0% ' + parseInt(-x / 2) + 'px, center top');
});

In css:

#main {
background: url(../img/img1.png) center top no-repeat, url(../img/img2.png) center top no-repeat, url(../img/img3.png);
background-repeat: no-repeat, no-repeat, repeat-x;
background-position: right top, left top, center top;

Where #main is the div whose background image I wanted to move. No need to have height: 100% for html, body.

This is a variation for multiple background images.

Solution 4

This might do it:

$(window).scroll(function(){
    $('#div').css("background-position",parseInt($(this).scrollTop()*0.05));
})

View more solutions

Comments

[mtwallet]

Thanks for the reply. I have tried different variations of this code but cannot get it to work I'm afraid.

[mtwallet]

@Hussien tried your suggestion (many thanks!) but not working just yet. I noticed on jsfiddle you're using jQuery UI which I'm not yet. Which part does this depend on, is it position?

[Hussein]

@mtwallet jQuery UI has nothing to do with the code. You can do without it. It's just a habbit that i include both UI an jQuery when i use jsfiddle.

[mtwallet]

@Hussien in which case not sure what I'm doing wrong. I've set up my own JSFiddle if you don't mind having a quick look. jsfiddle.net/nicklansdell/HFxVj

[Hussein]

@mtwallet you need to have body, html{height:100%; min-height:100%;} not just body. Check it out here jsfiddle.net/HFxVj/2

[mtwallet]

@mtwallet Awesome that works a treat! Thanks a lot for all your help. 50 points coming your way! : )

[Matt]

Thank you so much, Hussein. Such a beautiful, simple solution.

[benbyford]

Probably worth checking out requestAnimationFrame too for smoother animations - here is a good loop i found googling gist.github.com/Warry/4254579