High performance avatar clothing is a new feature for developers working in "Space", the new Unity-based virtual world from Second Life/OpenSim veterans (a proud sponsoring partner to this blog):
The new Space clothing shader uses tessellation to deliver high frame rates, high concurrencies and amazing details all at once. The new custom shader gives virtual world clothing and accessory designers technology used in the latest AAA games. The tessellation creates multi-million polycount levels of detail on clothing, taken from normal tangents and height maps.
"Tesselation" is a fancy way of saying it simulates cloth at high-resolutions (as pictured above). Or as Space lead developer Adam Frisby puts it: "This is good for things like fabrics, curtains, drapery - where doing the detail work is quite polygon expensive. You can make a flat mesh look like it's highly curved using tessellation without increasing the polycount costs."
That means avatars can wear highly detailed clothing in Space without much additional lag for avatars around them. "I'd say around 200-300 avatars while maintaining an acceptable framerate on moderate PCs (acceptable being 15fps+)", says Adam.
For developers, the wiki for designing detailed clothing in Space is here, and there's a video tutorial you can watch below, which also shows the clothing in action in a high concurrency simulation: