Hi!

Being new here I am not new to Linux, but I am totally lost in this question.

I recently installed Fedora Workstation 25 and applied my usual configuration - xdm, xorg, icewm and also my monitor is turned to be vertical and my xinitrc use xrandr -o right. This worked for me on different platforms without issues for years.

On Fedora 25 i see something strange. For certain applications images are condensed from left and right and I suspect Qt library guilty for that. That means everything is ok but main working window. For now known applications doing that are qpdfview and UGII (this is 3d-modelling system). Other apps, like DraftSight or FreeCAD or image viewer or video player do not do that.

I don't dare UGII is qt-based - I just believe it is. However meshlab or freecad (both qt-based) work as expected. Comparing ldd output for qpdfview and meshlab - found nothing different. Also this worked nice on Debian 8 system.

One more fact - if I apply xrandr when application is already working - it work as expected before and after xrandr. Bug can be noticed only if application is ran after xrandr.

I have totally no idea where to look at in this situation, hope some can help, thank you in advance.

Finally I got an answer.

For some reason modern xrandr do not swap screen physical dimensions. You can check it via xdpyinfo. In this case some applications count wrong DPI dividing milimeters to points.

This also corrupt font behaviour - in my case GTK2 applications was needed to set "tahoma 6" and GTK3 ones use "tahoma 8" to show "tahoma 8" in fact.

If you call randr in xorg.conf via Option "Rotate" "left" you do the work right.

Also important to check right monitor output in Xorg.0.log because in my case DVI connector actually use HDMI1 logical output.

Missed the answer. Thanks.

I'm surprised you got Xorg on a F25 install - I thought Wayland was the default. That might cause you a whole new collection of problems.