Re: No refresh using compiz/VNC and X 1.7
I looked into this today and found that the NVIDIA driver does not correctly generate damage events for a given window when the OpenGL rendering is actually happening to a child window. In this case, x11vnc is listening for damage events on the root, but Compiz is rendering to the Composite Overlay Window, which counts as a child window as far as this code is concerned. I'll try to fix the window hierarchy problem for a future release.
In the meantime, you can work around the problem by using Compiz's --use-root-window option, or by modifying Compiz to call XCreateDamage(dpy, cow, XDamageReportNonEmpty) to trigger damage events on the root window when it renders to the COW.