Originally Posted by krionius
This paper is rather interesting. But composite and such does not equal XGL concept AFAIK, and this paper is about such things. This is now about real 3D not just beautified 2D. How does these two bit different things connect now?
The paper is all about how you do 2D on top of 3D. That's what XGL is all about, too - rendering all of the 2D X drawing commands using the 3D hardware.
XGL manages to make those effecets possible by forcing all 3D to be done indirectly; that is, the clients no longer directly talk to the hardware, but instead talk to the X server that talks to the hardware. That's necessary to make a composite manager that uses 3D work.
The work done by IBM, X.org, and Red Hat on the accelerated indirect rendering branch of X.org allowed the current X.org server to support both direct and indirect hardware accelerated rendering. And it does it with much less impact on the X server code, and doesn't require building an entire new set of drivers from scratch like Xegl will.