Re: [gentoo-user] Why is KDE so bad at multiple monitors?

[Daniel Frey <djqfrey@gmail.com>]

On 2/29/24 03:27, Dale wrote:
> To provide a little more info on how this works.  This is how I did it.  
> It helps a LOT to have tab completion with this.  It will fill in a lot 
> of the info and when unsure, list the available options. First, I had to 
> install the package xrandr.  My first problem is the command isn't 
> available since it wasn't installed.  So, if you don't have it, install 
> it. It's tiny.  This is what I have for my setup. You can ignore that I 
> watch TV and just pretend you have two monitors side by side or whatever 
> and get the same results.  I have a DB15HD connector, referred to as VGA 
> within xrandr.  That is my main monitor.  The second monitor is is 
> connected to a HDMI port, seen as same in xrandr, and what I watch TV 
> with.  This is the output I started with to get good clues.
> 
> 
> root@fireball / # xrandr --listmonitors
> Monitors: 2
>   0: +*VGA-0 1920/598x1080/336+0+0  VGA-0
>   1: +HDMI-0 1920/1150x1080/650+1920+0  HDMI-0
> root@fireball / #
> 
> 
> Since I have different ports, it is easy to see which is which.  The 
> last bit is what you use in the command, not the first bits.  If all 
> your ports are the same, mini HDMI for example, I think the port lowest 
> to the bottom of the video card is number 0, or the first port.  Anyway, 
> mine is easy.  I then typed in xrandr --output and hit tab twice.  It 
> will list all the available monitors.  Pick the one you want to be the 
> first output or main monitor.  In my case, VGA-0 as shown on the end of 
> line one.  Once you type enough, tab completion will fill it in.  Then 
> add --primary to that to make it the primary display.
> 
> For the second monitor, continue on with the command and tab 
> completion.  Type in --output and hit tab twice again to list options.  
> Pick the second monitor and type enough in for tab completion to fill in 
> the rest.  Then add --right-of, --left-of, --above or --below and then 
> the output device for the main monitor. For me, this is what my command 
> looks like.
> 
> 
> root@fireball / # xrandr --output VGA-0 --primary --output HDMI-0 
> --right-of VGA-0
> root@fireball / #
> 
> 
> That makes VGA the primary, HDMI-0 second and to the right of VGA-0.  If 
> you have more than two monitors, just keep adding --output and list and 
> place the other monitors.  I don't have the means to test but that 
> should work.  I'd think setting the primary is key in this so I wouldn't 
> forget to include that.
> 
> Once you get that command, you can test it by going to a Konsole if 
> using KDE or some other similar tool you can type commands in as root 
> and run the command manually.  If it works correctly, add the command to 
> the file in this path.  /usr/share/sddm/scripts/Xsetup  I haven't logged 
> out and back in again yet so we will see when that happens if it really 
> works and my little quirk goes away.
> 
> There is a man page for this.  It may have other options that you may 
> need to add.  Just keep in mind, what is between each --output is what 
> it applies too.  One could have different resolutions, image flipped or 
> something and lots of other options.  Just keep the options in the right 
> section of the command.
> 
> I hope this helps someone and makes decent sense.  I also hope it works 
> after I logout and back in again.  :/   I'm making a note of the 
> location in case I need to comment it out.  Better to be safe than 
> sorry.  LOL
> 
> Dale
> 
> :-)  :-)

I've been gone for a few days as I was rebuilding my main PC.

I thought I'd provide an update: it was xorg-server causing all the issues.

I figured as I had to redo everything anyway to switch to systemd and 
wayland as that's what the bigger DE's tend to be supporting nowadays.

After fiddling around with systemd for a day (I'd tried it once before 
converting a system from openrc->systemd and failed miserably - nothing 
worked) I've reconfigured most things the "systemd" way.

I guess starting fresh solves all sorts of issues. :o)

Some things I like about systemd:
   - It is capable of automounting NFS shares out of the box; I just
     configured fstab so systemd automatically generated the automount
     configured it required. No extra steps needed;
   - It provides a scrollable list by default showing all the items you
     have access to in order to change how your machines behaves;
   - It isolates services in logs. This was helpful when sddm didn't want
     to behave.

Some things I don't like:
   - It has nutty network configuration. It was applying an APIPA network
     address as the primary for my interface which broke all sorts of
     tools. Took me a while to figure out how to stop that.
   - It doesn't update resolv.conf even though I'd specified a DNS
     server! So literally nothing worked. For now I manually removed
     resolv.conf and put the DNS server there. Plan to use something
     else for network management that sets resolv.conf properly. I have
     no desire to use networkd-resolved.

But, back to the original problem...

I don't know what was broken in my original system. I always had to 
reconfigure monitors every time I logged in.

As I mentioned I switched to wayland and on the fresh install it 
actually gave me a desktop. I set the monitor orientation and location, 
and I can log out and back in and it remembers the monitor orientation 
and location now. Which is what I was trying to solve.

However, sddm was still quite broken and the monitors were in some 
default strange configuration that made no sense. I fought with this 
with xrandr trying to solve it and nothing I did would make it stick. I 
then found in KDE's sccm settings you can apply the wayland desktop 
settings to sccm - I did that but was disappointed when I rebooted that 
it didn't work. What did work was reading the docs and switching sddm to 
use wayland and kwin instead of X11! Once I did that, now the monitor 
layouts are the same between the desktop and sddm. So I'm happy about that.

Other issues I came across were forgetting the kernel config for nvidia 
cards and tty output. It took me a lot of head scratching and searching 
to realize I had enabled something in the kernel that was doing this.

The sound server also dramatically changed as I had no sound at all from 
KDE but I could see, use and get sound from the shell. Some new pipewire 
thing. I really wish that devs would fix existing things that have 
issues instead of making a new thing that doesn't work.

Other than that, I really had no issues. Was able to mount encrypted 
volumes with no fuss.

I'm now working on the important bits - customizing KDE again and 
restoring my backups.

I did have an odd issue (well, still have actually - it's not resolved) 
with microcode but I'll create a new thread for that.

So, wayland and systemd actually fixed something for me. Who would've 
thought...

Dan