You are not logged in.

#1 2020-10-16 23:47:20

Registered: 2015-02-10
Posts: 37

Share a window on two display with dwm ?

I’m struggling to achieve something I thought would be simple. Not directly arch related, but I know there are lots of dwm users here.

With distant teaching and hybrid seminar formats,  I have to deal with students or peers in the room and on zoom at the same time.
I’m used to duplicate my screen between two displays during presentations, but I can't find a way to display a window on both displays at the same time. The fact is that I’m skilled with dwm, but my workflow collapse when I do multi-screens.  I’m a bit lost with x server, compositors, etc.
With semi-distant teaching, it is becoming crucial for me to remedy these weaknesses.

What I want to do is to have a pdf open on my main screen (laptop), share it on zoom, and display the window on the projector (without duplicating the whole main display). I can't find something like mod + shift + number that would tag the window to be displayed by screen 2.

Or a way to have two synchronised zathura instances (scrolling in one would scroll in second).

Am I approaching the problem the wrong way ? Is my dwm muti-head wrongly configured ? What should I dig into in order to achieve that ? Missing the obvious ?



#2 2020-10-17 00:02:24

Inspector Parrot
Registered: 2011-11-29
Posts: 24,454

Re: Share a window on two display with dwm ?

I have no idea how zoom sharing works, but if you are hoping to have the same window displayed on two screens you have limited options.  Mirroring of course would work, but this would be showing the exact same content on both screens - you can have one screen showing only a portion of the content (e.g., a subset of what is on one screen on the other), but you can't have the same window with different geometries (widow geometry being it's WxH+X+Y) - there is simply no way to do this in Xorg (*maybe* there is in wayland a way to have two views of the same client).

If you want to stick with Xorg and DWM, your best bet would be the syncronized instances, though not even necessarily two instances of the program, just one program with two seperate windows: this is in fact quite common for presentation software in which you'd have one window on the projector output and a different window showing the same pdf content on the internal monitor output.  The important distinction here is that there are two seperate X11 windows each with their own geometry that just happen to be showing related content (in contrast to having one X11 window in two places which is impossible).

"UNIX is simple and coherent..." - Dennis Ritchie, "GNU's Not UNIX" -  Richard Stallman


#3 2020-10-17 03:01:52

Forum Fellow
From: Between Thailand and Singapore
Registered: 2009-03-17
Posts: 7,255

Re: Share a window on two display with dwm ?

One workaround is to use OBS, which can take the input of a window, a screen, or anything else really and output it as a webcam feed.

You can also just show them the OBS window (maximize the display).

You can also do a preview of the OBS window in your other screen. Many possibilities. Once this is setup you just do what you're familiar with, and they will see your zathura window. There's many more possibilities (layering your face on it, for example), but this is just to answer your question.

Allan-Volunteer on the (topic being discussed) mailn lists. You never get the people who matters attention on the forums.
jasonwryan-Installing Arch is a measure of your literacy. Maintaining Arch is a measure of your diligence. Contributing to Arch is a measure of your competence.
Griemak-Bleeding edge, not bleeding flat. Edge denotes falls will occur from time to time. Bring your own parachute.


Board footer

Powered by FluxBB