How to create OpenGL-enabled window with transparent background using xlib and glx

I'd like to create a window with transparent background and then render something onto it using OpenGL. I don't want to use the trick where whatever is behind the开发者_JAVA技巧 window is captured and then painted as a background - I want real transparency (I have composition manager running). I'm not using any GUI library (GTK, QT, ...), just raw xlib and glx.

Anyone knows how to do it?

Take a look at these patches to Neverball and SDL. They seem to be based on NVidia's driver documentation.

I haven't tried it, but it looks as if you just select the correct GLX config (GLX_RGBA_BIT), clear your window appropriately, and have a compositor running, it should Just Work™.