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rorique

Member

Registered: 2015-03-22

Posts: 16

i3+compton on Multihead setup with hidpi and Scaling

I tried the following .xinitrc:

xrandr --dpi 220
xrandr --output eDP-1 --scale 1x1 --mode 3200x1800 --fb 3840x3960 --pos 0x2160
xrandr --output DP-1 --scale 2x2 --mode 1920x1080  --pos 0x0
sleep 15
exec i3
compton -cCGb --backend glx --vsync opengl

I added the sleep to make sure i3 starts after the xrandr commands finished, without the sleep the scaling did not work.

The problem is, that compton is running but not working and I'm getting a lot of tearing and in Chromium even the cursor is flickering.

I read the Wiki-entry about compton with multiple monitors but that did not help either.

Awebb

Member

Registered: 2010-05-06

Posts: 6,286

Re: i3+compton on Multihead setup with hidpi and Scaling

Well, compton executes after i3 terminates, which it won't until you exit i3. Swap the exec and compton line and add the & to the compton line. Look up, how the .xinitrc works. Don't forget the &.

EDIT: Read the startx wiki article.

Last edited by Awebb (2016-07-21 19:05:11)

rorique

Member

Registered: 2015-03-22

Posts: 16

Re: i3+compton on Multihead setup with hidpi and Scaling

I tried that. My problem was and is not to start compton, the problem is the result. My feeling is, that scaling doesn't work with compton, at least I haven't found a way to make it work.
The tearing and flickering looks different from i3 without compton, but it is not any better.

Awebb

Member

Registered: 2010-05-06

Posts: 6,286

Re: i3+compton on Multihead setup with hidpi and Scaling

Then please bring order to chaos. What you actually want to do is getting rid of tearing, is that correct?

rorique

Member

Registered: 2015-03-22

Posts: 16

Re: i3+compton on Multihead setup with hidpi and Scaling

Yes. Only using the laptop hidpi screen works (no tearing). Using the hidpi laptop screen and a "normal" monitor (1920x1080) also works without tearing, if I do not use "scale 2x2" in order to make the monitor usable. If I do then compton still starts and the tearing looks different from when I don't start it, but it is there. Also the cursor is flickering then, but only if I use compton.

So what I would like to do is to get rid of the tearing while using the scale parameter or an adequate alternative, so I can use the second screen.

Awebb

Member

Registered: 2010-05-06

Posts: 6,286

Re: i3+compton on Multihead setup with hidpi and Scaling

Maybe we can eliminate the need for --scale. Please elaborate, why --scale 2x2 makes the external screen "usable". We might find a better solution.

rorique

Member

Registered: 2015-03-22

Posts: 16

Re: i3+compton on Multihead setup with hidpi and Scaling

I got it from this thread: http://askubuntu.com/questions/393400/i … ent-screen

Changing font size doesn't help either because I cannot do it differently for the different screens.

Head_on_a_Stick

Member

From: London

Registered: 2014-02-20

Posts: 7,732

Website

Re: i3+compton on Multihead setup with hidpi and Scaling

What is your hardware?

I use https://wiki.archlinux.org/index.php/In … free_video to control tearing on Intel cards.

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Are you infected with Wetiko?

rorique

Member

Registered: 2015-03-22

Posts: 16

Re: i3+compton on Multihead setup with hidpi and Scaling

Yes, I'm using Intel Corporation Iris Graphics 540.

There is no tearing with the GPU driver option you mentioned, but X is freezing after a few minutes with it set.

Last edited by rorique (2016-07-25 13:25:28)

d.hensen

Member

Registered: 2015-10-08

Posts: 19

Re: i3+compton on Multihead setup with hidpi and Scaling

@rorique Did you ever figure this out?

I'm using a 4K laptop display together with a FullHD external display with the following setup:

# Downscale eDP1, because the 7680x2160 is too much for the integrated GPU
xrandr --output HDMI-1 --scale 1x1 --mode 1920x1080 --fb 3840x1080 --pos 0x0 --right-of eDP-1 &> xprofile.log
xrandr --output eDP-1 --scale 0.5x0.5 --pos 1920x0 &> xprofile.log

When using this together with compton I always get tearing. (I tried a lot of different compton settings)

I found some resources that are suggesting that multi-monitor setups are going to have this problem because of vsync not properly working... (OMG the developer only has one monitor):
https://github.com/chjj/compton/issues/175
https://github.com/chjj/compton/wiki/vsync-guide (search for Multiple monitors)

Please let me know if you have overcome this issue!

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contain skype in systemd-nspawn container