Created attachment 53445 [details] Fonts unreadable small Version: unspecified (using Devel) OS: Linux I use Virtualbox for testing KDE trunk. With Guest Addons installed the Guest‘s screen resolution will automatically set according to the VBox window size. Often this results in fonts either being huge (when I maximize the window) or being unreadable small (when I accidently resize it small). This is really annoying. Especially because those font size changes don‘t instantly apply, they only apply to new opened applications/windows. So you open a new instance of Dolphin and end up having text huge in there and normal on the desktop or vice versa. Reproducible: Sometimes
The font size is specified in points instead of pixels, and this requires sane DPI information provided by the underlying components (hardware, drivers, etc.) If VirtualBox allows the screen pixel dimension to be changed together with the window size, it should also change the physical dimension of the screen so that the DPI remains constant. To verify, please run the "xrandr --prop" command inside VirtualBox. The physical display dimensions (??mm x ??mm) should change together with the window size, if they don't, report it to the VirtualBox developers (VirtualBox probably internally uses XRandR to simulate display size changes. If it does, there is a way to specify the DPI using XRandR calls, too). You might also be able to start the virtualized X server with a forced DPI value, but I am not sure if that option is deprecated and will be overridden by xrandr.
So I executed your command but I don‘t know how to interpret them so I‘ll just post their results: Maximized window (how KDE started) Screen 0: minimum 64 x 64, current 1920 x 1101, maximum 32000 x 32000 VBOX1 connected 1920x1101+0+0 0mm x 0mm 1920x1101 60.0*+ 1680x1050 60.0 1600x1024 60.2 1400x1050 60.0 1280x1024 60.0 1440x900 59.9 1280x960 60.0 1360x768 59.8 1152x864 60.0 1024x768 60.0 800x600 60.3 640x480 59.9 After resizing smaller Screen 0: minimum 64 x 64, current 640 x 480, maximum 32000 x 32000 VBOX1 connected 640x480+0+0 0mm x 0mm 640x480 60.0*+ Again maximized Screen 0: minimum 64 x 64, current 1920 x 1101, maximum 32000 x 32000 VBOX1 connected 1920x1101+0+0 0mm x 0mm 1920x1101 60.0*+ 1680x1050 60.0 1600x1024 60.2 1400x1050 60.0 1280x1024 60.0 1440x900 59.9 1280x960 60.0 1360x768 59.8 1152x864 60.0 1024x768 60.0 800x600 60.3 640x480 59.9
Try this command instead (before and after): xdpyinfo | egrep "dimensions|resolution" Usually a display does not get smaller when you select a different resolution, the pixels get larger instead. But for VirtualBox, the pixel density should stay the same.
Ah okay then it is a bug in Vbox. At the start the resolution is the correct for a monitor 96x96 dpi. When I resize it, this value changes. For example then it was just 32x43 dpi