In The VirtualGL Project, we've traditionally referred to that mode of
operation as "seamless windows". Unfortunately, no VNC solution can
accommodate seamless windows, because the RFB protocol doesn't
accommodate them. RFB stands for "remote framebuffer", and the name
reveals its original intent: to display the contents of a framebuffer
remotely. That framebuffer can be a physical GPU-based framebuffer in
the case of screen-scraping VNC servers (WinVNC, x0vncserver, x11vnc,
etc.), or it can be a virtual main-memory-based framebuffer in the case
of Xvnc, but the protocol itself works the same regardless. The VNC
server basically just sends compressed image tiles with coordinates
attached to them, so the VNC viewer knows where to draw each tile.
Supporting seamless windows would require a richer protocol that
includes remote window management primitives as well as per-window
framebuffer update messages.
There are other (non-VNC-based) open source remote display solutions
that support seamless windows. Xpra is probably the most
straightforward of them, in my experience.
DRC
On 5/4/21 11:23 AM, 'Derick Behrends' via TigerVNC User