Custom resolution for SDDM

d_fajardo · 2017-08-02 06:53:26

I recently bought an 4K 28" Samsung monitor. The quality is really superb watching videos. However for everyday computing, I find that the 3840x2160 native resolution is too high and the texts are hard to read so I've set my native resolution via the KDE settings module to 2560x1440 and I'm happy with this. However when I boot, SDDM is rendered with the native 3840x2160 resolution, and after login it returns to my 2560x1440 resolution. I'd like the SDDM to have the same resolutipon as my settings.

I've tried several methods but they all; don't work. One method is updating the Xsetup script at /usr/share/sddm/scripts/Xsetup and using xrand:

xrand --output DP1 --mode 2560x1440

Another method is updating the sddm.conf script with DPI ass described in the wiki:

[X11]
ServerArguments=-nolisten tcp -dpi 105

I also tried:

[General]
# Enable Qt's automatic high-DPI scaling
EnableHiDPI=false

None of these worked. I believe the question is how do you set a custom resolution for the system before SDDM starts. I understand that the native resolution is automatically configured by KMS but is there a way of passing some parameters to the intel driver (the one I'm using is i951) for a custom resolution? Or perhaps setting up Xorg for a custom resolution before SDDM kicks in? Or am I missing something with SDDM?

Last edited by d_fajardo (2017-08-02 07:02:20)

seth · 2017-08-02 07:29:31

https://wiki.archlinux.org/index.php/Xr … figuration

d_fajardo · 2017-08-07 20:16:39

Thanks Seth. I had a close look at xrandr and tried a few things but without success. I also tried creating a 10-monitor.conf in my xorg directory to enable resolution I wanted. It didn't work and even messed up the graphics as I started having black backgrounds on some icons and my conky so I abandoned the idea. What I don't understand is why the Xsetup script in sddm directory is not being read when it's supposed to be read as root before starting the display

Any further suggestions?

seth · 2017-08-07 20:27:15

stat /usr/share/sddm/scripts/Xsetup
cat /usr/share/sddm/scripts/Xsetup

xrand --output DP1 --mode 2560x1440

xrandr

Also please show the 10-monitor.conf you tried.

d_fajardo · 2017-08-07 20:41:48

Sorry seth, already deleted the 10-monitor.conf. I'll look further into it and perhaps create a new 10-monitor.conf file. I'll come back to you.

seth · 2017-08-07 21:28:00

Seen the commands reg. Xsetup?
Ensure the file to be executable and contain a shebang.

d_fajardo · 2017-08-09 09:43:30

#!/bin/sh
# Xsetup - run as root before the login dialog appears

xrandr --output DP1 --mode 2560x1440

This is what I have for my Xsetup.

And this is my stat for that:

File: /usr/share/sddm/scripts/Xsetup
Size: 103 Blocks: 8 IO Block: 4096 regular file
Device: 19h/25d Inode: 937010 Links: 1
Access: (0755/-rwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2017-08-09 10:39:35.660849728 +0100
Modify: 2017-08-09 10:39:35.650849727 +0100
Change: 2017-08-09 10:39:35.650849727 +0100
Birth: -

It looks like permissions are fine or are they not?

Last edited by d_fajardo (2017-08-09 09:44:03)

seth · 2017-08-09 11:05:20

No, looks good.
Ensure it's actually ignored and not just reverted. Add

echo "ran Xsetup - `date`" > /tmp/sddm.xsetup.done

and check whether that file appears.

d_fajardo · 2017-08-09 20:40:26

Yes seth it did output the file. I'm beginning to think its an sddm bug because even with the Arch wiki on sddm setting the dpi mode doesn't work.

seth · 2017-08-10 06:04:59

Are you sure the resolution is reset?
Switch back to VT1 and check xrandr -display :0

Do you still have the EnableHiDPI=false setting?

d_fajardo · 2017-08-11 11:19:01

Just an experiment, I have Manjaro installed in my laptop where everything works pretty much out of the box. The native resolution is 1733x768 so I decided to see if the SDDM will accept a lower resolution and did the same things as I did with my arch system. I get the same result. SDDM won't change to a lower resolution although I can do so after login with xrandr.

I've decided to just keep the HiDPI setting all throughout. The 4K screen does look amazingly sharp with lots of space. I force dpi fonts to higher setting which works fine for KDE. The problems are in rendering GTK applications and other java applications wherein they appear really small. This can be a topic for another thread on how to make them bigger. I've tried some of the suggestions in the wiki but they don't work as yet.

Anyway thanks for your support!

dmitryb · 2017-09-18 12:34:17

@d_fajardo I think this is a bug in the latest SDDM release. Everything worked just fine for me with correct display size set in /etc/X11/xorg.conf.d/90-monitor.conf
But today after I did an upgrade:

[2017-09-18 10:30] [ALPM] upgraded sddm (0.14.0-2 -> 0.15.0-2)
[2017-09-18 10:30] [ALPM] upgraded sddm-kcm (5.10.4-1 -> 5.10.5-1)

I got super tiny font on my HiDPI laptop screen. I'm going to file a bug to the github project.

dmitryb · 2017-09-18 12:49:37

I filed a bug report here: https://github.com/sddm/sddm/issues/894

KorvinSilver · 2021-07-15 15:04:33

The beta driver didn't help, for now I restored the current one and reverted the changes for using only the dGPU. Maybe the iGPU won't cause issues. SDDM is also different, for some reason it defaults to 4K now. I may force 1440p on it.

seth · 2021-07-15 19:04:04

Did you reply to the wrong thread?
This one here is almost 4 years old…

KorvinSilver · 2021-07-15 22:05:30

oof, I did, no idea how

Arch Linux

#1 2017-08-02 06:53:26

Custom resolution for SDDM

#2 2017-08-02 07:29:31

Re: Custom resolution for SDDM

#3 2017-08-07 20:16:39

Re: Custom resolution for SDDM

#4 2017-08-07 20:27:15

Re: Custom resolution for SDDM

#5 2017-08-07 20:41:48

Re: Custom resolution for SDDM

#6 2017-08-07 21:28:00

Re: Custom resolution for SDDM

#7 2017-08-09 09:43:30

Re: Custom resolution for SDDM

#8 2017-08-09 11:05:20

Re: Custom resolution for SDDM

#9 2017-08-09 20:40:26

Re: Custom resolution for SDDM

#10 2017-08-10 06:04:59

Re: Custom resolution for SDDM

#11 2017-08-11 11:19:01

Re: Custom resolution for SDDM

#12 2017-09-18 12:34:17

Re: Custom resolution for SDDM

#13 2017-09-18 12:49:37

Re: Custom resolution for SDDM

#14 2021-07-15 15:04:33

Re: Custom resolution for SDDM

#15 2021-07-15 19:04:04

Re: Custom resolution for SDDM

#16 2021-07-15 22:05:30

Re: Custom resolution for SDDM

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