examples/09_relative_values.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>Tween.js / relative values</title>
		<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
		<link href="css/style.css" media="screen" rel="stylesheet" type="text/css" />
		<style type="text/css">
			.box {
				width: 100px;
				height: 100px;
				margin: 10px;
				padding: 10px;
				display: inline-block;
				float: left;
			}
			#target1 {
				background: #fcc;
			}
		</style>
		<script src="../dist/tween.umd.js"></script>
		<script src="js/RequestAnimationFrame.js"></script>
		<script>
			window.onload = function () {
				init()
				animate()
			}

			function init() {
				var target1 = document.getElementById('target1'),
					tween1 = new TWEEN.Tween(target1.dataset)
						.to({top: '+20', left: '-20'}, 500)
						.repeat(5)
						.delay(500)
						.easing(TWEEN.Easing.Exponential.In)
						.onUpdate(function (object) {
							object.top = Math.round(object.top)
							object.left = Math.round(object.left)
							updateBox(target1, object)
						})
						.start()

				updateBox(target1, target1.dataset)
			}

			function animate(time) {
				requestAnimationFrame(animate)
				TWEEN.update(time)
			}

			function updateBox(box, params) {
				var s = box.style
				var transform = 'translate(' + params.left + 'px, ' + params.top + 'px)'
				s.transform = transform
			}
		</script>
	</head>
	<body>
		<div id="info">
			<h1><a href="http://github.com/tweenjs/tween.js">tween.js</a></h1>
			<h2>09 _ relative values</h2>
			<p>Tweening to relative values, with repeat.</p>
		</div>
		<div style="position: absolute; left: 400px">
			<div id="target1" style="position: absolute" data-top="150" data-left="150" class="box"></div>
		</div>
	</body>
</html>