gtk, cairo, glitz, luminocity, what's their relation?

[writser xs4all nl]

Hey all,

I've read a lot lately about the future of gtk+/gnome. Things look very
promising. There is one thing I don't understand though. Cairo is able to
render scalable widgets using vector graphics. Glitz is a backend that
provides openGL acceleration for Cairo. So if I'm not mistaken, an OpenGL
accelerated window is drawn this way: gtk -> cairo -> glitz. But where
does the window manager do it's work? A new windowmanager, luminocity, is
in development. It provides OpenGL acceleration too. But using a Xgl
backend, afaik. But then what's the connection between glitz and
luminocity? Does glitz draw to the screen? Or does it only create textures
that are used by luminocity. And if so, then why do both glitz and
luminocity have opengl acceleration? Or is glitz just a temporary
solution.. I'd be glad if someone could clear things up :D