Animating Motion Along a Curved Path

The YUI Animation Utility allows you to animate the motion of an HTMLElement along a curved path using control points.

For this example, we will animate the position of a <div> element named demo. The points attribute, introduced in the YAHOO.util.Motion subclass, accepts an optional control field of one or more control points

Add a little style so that we can see the animation in action:

<style type="text/css"> #demo { background:#ccc; height:30px; width:30px; } </style>

Create the demo element and a button to run the animation:

<div id="demo">Demo</div> <button id="demo-run">run</button>

Now we create an instance of YAHOO.util.Motion, passing it the element we wish to animate, and the points attribute (an array of [x, y] positions), with the point we are animating to, and the control points that will influence the path:

<script type="text/javascript"> var attributes = { points: { to: [600, 10], control: [ [100, 100], [800, 800] ] } }; var anim = new YAHOO.util.Motion('demo', attributes); </script> <p>The final step is to call the <code>animate</code> method on our instance to start the animation. The button will be the trigger that begins the animation sequence:</p> <textarea name="code" class="JScript" cols="60" rows="1"> <script type="text/javascript"> YAHOO.util.Event.on('demo-run', 'click', function() { anim.animate(); }); </script>

This is an example of animating the motion HTMLElement along a curved path.

Configuration for This Example

You can load the necessary JavaScript and CSS for this example from Yahoo's servers. Click here to load the YUI Dependency Configurator with all of this example's dependencies preconfigured.