Since v0.16.0, DPI is being doubled for Windows clients.
$ xpra info | grep dpi dpi.default=0 dpi.value=96 dpi.x=0 dpi.y=0
$ xpra info | grep dpi dpi.default=0 dpi.value=192 dpi.x=0 dpi.y=0
Possibly introduced in r10953?
Are you sure that the DPI is wrong and that you aren't just seeing desktop scaling in action? (#976) I am seeing correct values, that adjust as I scale up or down (either via tray or ctrl shift +, ctrl shift -) Please include distro info, dummy driver / vfb info, client and server screen settings and resolution, etc.
It's reporting a dpi of 192 and everything is bigger than it should be, scaling is set to none. Server is Ubuntu 16.04, xpra 0.17.0, dummy driver is 0.3.7 with the patches from repo. Clients, Windows 10, tested xpra 0.16.0 and 0.17.0 (3 different systems, resolutions 1280x800, 1366x768, 14490x900), scaling is wrong with them. Xpra 0.15.10 displays as expected with no changes to server. If I remove dpi from my client config (then it uses auto), it's correct, dpi = 48 is also correct, reports 96 and UI is the correct size. My xpra.conf had dpi = 96 as that used to be the default. In ui_client_base.py, the provided dpi (either command line or xpra.conf) is being doubled.
#use command line value supplied, but scale it: xdpi = self.cx(self.cy(2.0*self.dpi)) ydpi = xdpi
2016-05-02 18:22:39,680 screen 0: ('1\\WinSta0\\Default', 1280, 800, 338, 211, [('\\\\.\\DISPLAY1', 0, 0, 1280, 800, 287, 180, 0, 0, 1280, 770)], 0, 0, 1280, 770) 2016-05-02 18:22:39,680 desktop size is 1280x800 with 1 screen: 2016-05-02 18:22:39,680 Default (338x211 mm - DPI: 96x96) workarea: 1280x770 2016-05-02 18:22:39,680 DISPLAY1 (287x180 mm - DPI: 113x112) 2016-05-02 18:22:39,680 dpi: 192, xdpi=192, ydpi=192
2016-05-02 18:22:46,777 client root window size is 1280x800 with 1 display: 2016-05-02 18:22:46,777 Default (338x211 mm - DPI: 96x96) workarea: 1280x770 2016-05-02 18:22:46,777 DISPLAY1 (287x180 mm - DPI: 113x112) 2016-05-02 18:22:46,777 maximum client resolution is 1280x800 (current server resolution is 1280x800) 2016-05-02 18:22:46,777 set_screen_size(1280, 800) xdpi=192, ydpi=192 2016-05-02 18:22:46,777 set_dpi(192, 192)
Hah, I was missing the fact that you're using the "--dpi=" command line option. You're totally right, the doubling is a mistake (in other places we average xdpy and ydpi, I must have cut&pasted it wrong).
Fixed in r12516. Will be in the next stable update. Feel free to close.
(editing ticket title - I don't think this is specific to MS Windows clients at all, this same code is used by all platforms)
Found another place that needed fixing: r12668.
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/1193