GUI scaling rendered KDevelop useless on Windows 10

[Ingvar Tjøstheim]

Thanks for this useful information.

This has only happened this one (aggregated) time.

If, or when it happens again, I will try to think of what reproduces it, and now have more ideas on hand on how to troubleshoot.

I will try to get back to you all with updates if I have any.

Thank you!

-Ingvar

-----Original Message-----
From: René J.V. Bertin <rjvbertin at gmail.com> 
Sent: 16 September 2021 10:49
To: Ingvar Tjøstheim <itj at automasjon.no>
Cc: kdevelop at kde.org
Subject: Re: GUI scaling rendered KDevelop useless on Windows 10

Ingvar Tjøstheim wrote on 20210916::05:53:04 re: "RE: GUI scaling rendered KDevelop useless on Windows 10"

(bouncing this back to the list)

>As KDevelop GUI scaling had enlarged before I got here, it remained this way as I connected here and switched monitors. I do not know if it worsened, but it has not reappeared yet.

Do you mean the issue is back already? How do you handle the suspend/commute/wake cycle? Do you disconnect the one dock before you suspend the computer and connect the other after you wake the computer? That seems the safer route . I used to do the opposite with the external screens on my Mac (not via a dock) and that went fine with older (= graphically simpler) versions of the OS until it no longer did.

>I will try to find out whether it is easier to reproduce at home, as I have not been able to do so here.
>When switching between monitors here, Windows 10 does scale all GUI, so I would think the problem could appear here too.

You say the monitor at work has a lower resolution, is it maybe one that wouldn't qualify as a "high dpi" screen?

Here's what Qt wants us to know about DPI scaling (have fun!) :
https://doc.qt.io/qt-5/highdpi.html

>From there, things you can try when the issue returns:
- start KDevelop with a specific `dpiawareness`
- start KDevelop with one of QT_AUTO_SCREEN_SCALE_FACTOR/QT_SCALE_FACTOR/QT_SCREEN_SCALE_FACTORS set in the MSWin environment
- start KDevelop using the Fusion style (the "native" MSWin style apparently has some issues with highdpi scaling).

Points 1 and 3 can be done via a qt.conf file (I think in the directory where KDevelop is installed; see https://doc.qt.io/qt-5/qt-conf.html), environment variables (like QT_SCREEN_SCALE_FACTORS) would apply to all Qt applications.

NB: that doc does state that monitors can have incorrect EDID information - but I think you'd be seeing the issue all the time if that were the case ... although that's also the kind of information that *might* be cached by an OS and become corrupted, esp. when you're swapping external displays regularly.

R.