window scrolling support

[bubnikv]

Hello.

In these COVID-19 times I am looking into remoting into my Linux box. On Windows RDP is a natural choice and it works extremely well. One thing that works wonders on Windows RDP implementation is scrolling: An information is sent to the client, which region is scrolled, thus its region does not need to be copied over the network. Is there any support for that feature in xorgxrdp? I suppose in contrast to Win32 there is no such information available at the XRDP framebuffer, so one would have to use some kind of heuristics to detect the scrolling. Does it make sense? We may design some hashing scheme for detecting scrolling over screen tiles.

Thanks,
Vojtech