[winswitch] automatic scaling for hidpi (4k) inconsistent

[Antoine Martin]

On 18/01/2022 06:10, Thomas Esposito via shifter-users wrote:
> I recently upgraded from a 1080p laptop to a 4k laptop. I use Windows 10
> for my client and have windows "Scale and Layout" set to 200% for my 4K
> screen and 100% for the others. When I have my Windows desktop expanded on
> multiple non-4k screens (i.e. 1440p), xpra windows automatically scale to
> 200% when they are on the 4k laptop screen and switch to 100% on the non-4k
> screens.
AFAIK, Win10 is doing that.

> This is with xpra's built-in display scaling set to  "None".
> However, when I am using ONLY the 4k laptop screen by itself, xpra windows
> aren't scaled, even though the windows display scaling is set to 200%. I
> need to manually set the xpra display scaling to 200% for everything to be
> readable.
I'm not sure that we can reliably do much better in this case.
Operating systems have a habit of doing things behind the scenes and 
lying about the real physical screen's dimensions and DPI.

What you're doing is upscaling the output by 200%, ideally what you 
would do instead is tell the server side to increase the DPI and 
hopefully the applications would then do whatever is needed to display 
properly (increase font size, whatever).

In practice, this doesn't work very well, especially when the 
applications are started before the client connects and configures the 
virtual screen.

Perhaps we should give the user the choice of not trying to synchronize 
the DPI, and upscale instead.

Can you please create a new gihub issue for this?
https://github.com/Xpra-org/xpra/issues/new/choose

Cheers,
Antoine