Eyes Above The Waves

David Reveman just demoed his latest Xgl work (an X server based on Glitz). It's incredibly impressive. He has virtual desktops as the faces of a cube, so you can switch desktops by rotating the cube. Then he played a movie in a translucent window, crossing a virtual desktop boundary so it wraps around the cube. Of course it keeps playing while he rotates the cube. All very smooth and pretty. Amazing.

It looks like on Linux the preferred hardware acceleration story for rich apps like Mozilla/Firefox will be to run the Xgl X server, and have Cairo talk to Xgl via Xrender. Xgl implements the Xrender calls using GL so we get the same sort of hardware acceleration we'd get if we used Glitz directly. With only Xgl talking to the GL drivers, we avoid the problem that the vendor GL drivers aren't very good at handling multiple processes banging on them simultaneously. The only downside is that Xrender doesn't support some of the operations we need accelerated --- e.g., gradients, non-affine transformations, and SVG-style filters. We'll just have to fix that :-).

The story on Windows remains a bit less clear...