I’m not really accustomed to seeing a lot of UI press about GWT so I was pleasantly surprised when Dietrich Kappe showed me the new spinner control he’s been working on. Most of you have probably seen Flash-based implementations, especially on Amazon, where images spin on a type of carousel. It’s a very cool effect.

The widget uses projection geometry (a view point and calculating image size and position based on where lines pass through the z=0 plane) and a little bit of trigonometry for the circle. Also, zIndex is set based on an object’s z coordinate. At this stage the implementation definitely performs differently based on machine horsepower and browser platform. It performs pretty well on IE7 and Safari 3, less well on Firefox.

This is still a work in progress but Dietrich already has plans for adding DnD and setting up clickable elements. GWT developers should love this control. Check out the demo here.