[qwertyuiop]

function animate(id, delta) {
	element = document.getElementById(id);
	from = 0;
	to = 1;
	duration = 100;
	start = new Date().getTime();

	setTimeout(function() {
	    var now = (new Date().getTime()) - start;
	    var progress = now / duration;
	        var result = (to - from)*delta(progress)+from;

	    element.style.backgroundPosition = "-"+result+"mm 0mm";
	    //element.innerHTML = result;
	        setTimeout(arguments.callee, 1);
	}, 10);
}

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