Little script that detects if an element is in the viewport and adds a class to it.
Just include the script and jQuery in your website tag and call it on the elements you want to check.
<head>
<script src="http://code.jquery.com/jquery.js"></script>
<script src="viewportchecker.js"></script>
<script>
$(document).ready(function(){
$('.dummy').viewportChecker();
});
</script>
</head>
The current available options are:
$('.dummy').viewportChecker({
classToAdd: 'visible', // Class to add to the elements when they are visible
offset: 100, // The offset of the elements (let them appear earlier or later)
callbackFunction: function(elem){} // Callback to do after a class was added to an element
});