UI and fonts are too big with right(native for display) DPI settings

[trinitronx]

@Nyakov13

This is what I am trying to do, but this renders everything to big.
My physical DPI is 183.

@Nyakov13

So it gives 182.278481DPI by width and 182.857143 DPI by height.
So I assume 182-183 will be good for it.

I measured it by the ruler

If you look up the hardware reports 355x200mm (13.98x7.87") screen size,
what means the same 183 DPI.

192 - will make everything even bigger (also, it seems that GTK applications(Firefox precisely), after some threshold (somewhere after DPI144) will use 192 DPI, what makes its UI and web pages gigantic.

Basically, I want to use screen native DPI and cannot understand why everything renders so big.

Your settings look good as far as I can tell.

Although, Xorg is known to be a hassle when configuring things for HiDPI displays. Also, it seems that KDE devs are working on HiDPI support recently. Finally, this thread talks about the need (or not) for xsettingsd with KDE Plasma >= 5.27

@Nyakov13

Also, can someone point me where and how I can change Gdk/UnscaledDPI
How to calculate it?
I tried to change ~/.config/xsettingsd/xsettingsd.conf
But it gets rewritten after reboot. Current settings:

Gdk/UnscaledDPI 98304
Gdk/WindowScalingFactor 1

This page says to calculate Gdk/UnscaledDPI by multiplying the DPI by 1024. For your example of 98304, it looks like it’s still set to 96: 98304 / 1024 = 96.

Maybe try setting it to: 187392 ? (183*1024 = 187392)

Disclaimer: I’ve never had to change this setting, so “take this with a grain of salt” / “your mileage may vary”, etc…

Again, maybe this thread about xsettingsd might be helpful?

@Nyakov13

But can someone with 96DPI screen help me to compare physical font size?

Unfortunately, I currently only have a non-standard HTPC display that’s basically a low-DPI (36) HDMI TV.

I’m currently also using Wayland + Sway, so I’ve had a much better DPI-aware & fractional scaling experience overall when compared to Xorg / X11. It seems that getting Xorg to respect HiDPI & scaling properly is complicated and messy.