On 29/03/2021 14:09, Kleomenis Katevas wrote:
> Thank you for your reply.
>
> I think this happens when an app writes directly to the GPU (thus making
> use of video acceleration). In that case, TigerVNC cannot see it.
> For instance, check this thread:
https://github.com/FD-/RPiPlay/issues/221.
> There is always the option of using gstreamer, but then you depend on the
> CPU (which is very limited in the Pi).
>
> Not sure what RealVNC does in this "Direct Capture" mode and bypasses this
> limitation.
>
GPU acceleration is definitely possible without breaking VNC. So it is
something broken in the raspberry pi graphics stack. Normally in such
cases the graphics driver is responsible for setting up hooks in the X
server to get the pixels if they are needed.
Evidently it is possible to work around this issue, but we have no such
workarounds and they would likely be specific to the pi.