Comment by saurik | Hacker News Reader

Comment by saurik | Hacker News Reader

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Maybe it is merely a documentation issue? I keep hearing stories on the one hand of people (such as yourself) who say they failed to get X working with multiple displays... and yet, a ton of software seems to exist predicated on the notion of working with multiple displays (even i3) and a number of actual users claim to have multiple displays working.

https://ptgamr.notion.site/xrand-4k-mixed-monitors-7a026e534...

^ maybe this would be useful? This seems like a pretty simple single run of xrandr that configures multiple (three, even) monitors on X all at different resolutions and ending up at different display scaling (including one fractional scaling). Like, looking at this, I feel as if I should be able to get this working myself, were I to have multiple monitors (I don't on my Linux laptop).

FWIW, I love the idea of helping someone not be sad about having to switch to Wayland by getting them back on X with all of their happy software working, and so if you want to try to debug whatever your issue was together, I'm game. To me, what makes Linux fun is all of the random combinations and hacking we can do together, and it just seems like people are both losing that ethos and even saying we are wrong for enjoying it, and that makes me a bit demoralized :(.

Multiple displays work on X11 by having one big canvas/virtual display, and having each monitor show the contents of a part of that canvas.

There are some restrictions because of this. One is that per display scaling is unsupported in the worst case, or a hack in the best case.

Another is that the virtual display is always a rectangle, meaning that if you have different resolution displays, you end up with some parts of the canvas not being displayed anywhere. Most window managers and desktop environments know not to place window contents or UI chrome there (like panels), but the space is still there, and you can see this when using screenshot utilities which simply write the whole canvas to a file. Your mouse pointer can also hide in these invisible sections.

Getting X11 to display content on video outputs located on different video cards from different vendors can sometimes feel like a dark art, but other than that it mostly just works.

1) FWIW, I understood that, given the xrandr explainer that I linked, which was clearly doing all of that ;P.

2) Regardless, the person I'm replying to was using i3 (and is now using Sway), so I'm thinking that a lot of these limitations don't matter much? I mean, with i3 you aren't even going to ever have a window crossing the boundary between two monitors much less ending up off-screen somewhere.

3) I use a ton of random monitors at wildly different resolutions on Windows and frankly it's the same thing: there is a conceptual bounding rectangle for all of the monitors and you can absolutely have Windows hanging off the edge of monitors; also: I don't know how you expect anything to support non-rectangular screenshots so all of my screenshots on Windows--as well as my VNC servers--all have the same behavior with dead space.

4) Ok... I guess I can see the mouse thing being really annoying (as on Windows at least my mouse is locked to the visible area), but it doesn't seem to actually be the case? Again: maybe this is a documentation issue?

https://stackoverflow.com/questions/34092554/x11-restrict-mo...

Either you edited your comment, or infinitely more likely, I replied to the wrong comment

I don't know...I looked up dozens of pages and tried all of them. One monitor I have to scale down to 50% and the other one is native res, I think that's what caused me problems. I remember getting it to work but having issues with it either not displaying fonts properly because of all the weird scaling stuff or having things display off-screen and all that. I don't remember the exact reasons for seeking out Wayland but I remember having a really glitchy time on X with multiple monitors at different resolutions/scales. It was one of the very first things I tried on Sway and it really just worked instantly and intuitively exactly how I wanted.

It's possible the link you sent would solve the issue for me, but at this point I don't really have the energy to load up X and try again. I've since switched out a bunch of my workflows to adapt to Sway and the interruption would cost more to me than just living with the Wayland bugs.

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