5 ms·

Gnome 40 Introducing Headless Native Back End, Virtual Monitors

69 points by nikodunk 6y ago

kevincox 6y ago
The virtual monitors feature is niche but very useful when you need it. It is useful for screensharing when you don't have a spare monitor to use but want to arrange a couple of windows. It is so useful that people by dedicated hardware to convince their system to give them another monitor. (HDMI dummy plugs)
- foobar33333 6y ago
  Its useful for steamvr too which shows you your monitors so a dummy monitor gives you an extra monitor in vr
- samus 6y ago
  Is is about showing only a certain section of the screen where you have arranged those windows, instead of all of it?
rektide 6y ago
This is one of the sort-of-frustrating as-a-user things about Wayland to me, that every compositor (nee window manager) has to implement capabilities like this for themselves, where-as in X, there was common tooling. And they'll all have different userland tools to use these capabilities. here[1] for example is wlroots/sway implementing headless. That said, the implementations are great, & really show how much Linux has progressed. For a while it wasn't possible (for some reason I wasn't having good luck with either mdi or dp dummy plugs on my type-c only laptop), but I'm really looking forward to using one laptop as a virtual desktop for another desktop, & this work is core to that effort. I like a lot that Gnome was super smart & made outputting a virtual monitor as a PipeWire stream built in!! Smart easy win to make screen capturing even easier. Edit: at my posting rate-limit, so tacking this on, especially to @spivak, I like the diversity a lot, yes. But I still would like to see a situation other than gnome having it's own tooling to configure virtual monitors, wlroots having it's own, kde having it's own. Is this just an insufficienct protocolization problem right now? Are there wayland protocols to do things like change a monitor's resolution? Or to change the mouse speed? I think of Wayland protocols as more between a running app and the compositor, which has all been nicely modularized & protocolized. But I don't understand what if any effort has been made to find a common ground to expose user tooling. It feels like they all have their own suite of command line utilities. Swaymsg in sway, for example. Whatever this virtual monitor tool gnome has. How do we begin to modularize these control interfaces? [1] https://github.com/swaywm/wlroots/commits/master/backend/headless https://github.com/swaywm/wlroots/commits/master/backend/hea...
- neolog 6y ago
  There could be another library providing these common utilities, which multiple window managers could use.
  - zbuf 6y ago
    Is there a library providing these common utilities, which multiple window managers could use?
    - tobasq 6y ago
      Yes, wlroots is such a library.
    - akvadrako 6y ago
      Most wayland features implemented by a plurality of compositors are in the wlroots library. This feature probably isn't in a library though since it's from Gnome.
  - sprash 6y ago
    Or it could be part of the Wayland protocol from the get go sparing everyone of major headaches. At some point you arrive at a core functionality resembling X11 and you went full circle breaking everybody's workflow and tooling in the process for no reason other than severe NIHS.
    - mixedCase 6y ago
      Have you considered that maybe it was not done just to spite you and break your workflow? Or that maybe it does have something to do with having a maintainable implementation that doesn't work under assumptions that stopped being valid 20 years ago which make modern usecases extremely hard or impossible to support? And that indeed, the protocol has been growing and new standards have been in development concurrently with X.org maintenance in order to have a smooth transition? You're proposing that having everything ready from the get go would be much better, but that goes against pretty much every principle we know about designing large, complex systems, where BUFD results in huge messes that don't conform to reality, and can never do so, unlike a minimalist protocol that grows over time with careful approaches.
hollander 6y ago
ELI5 please. What is a headless native back end? These articles seem to be written for people who already know that it exists and what it is. How does that virtual monitor work?
- AceJohnny2 6y ago
  Desktop environments like Gnome assume the hardware on the machine they're running on is all the displays they'll ever have to deal with. "Headless" means there is no display (the "head" of the computer) connected to the machine. This update allows Gnome to use virtual monitors.
deanclatworthy 6y ago
This is fantastic. I have a box in the corner with no display attached and wasn’t able to RDP/VNC etc into it as there was no real display. I had mixed results with an abandoned virtual display package and ended up purchasing a tiny HDMI thing that plugs in the back and emulates a real display.
- haldean 6y ago
  Do you have a link for the HDMI dongle thing?
  - deanclatworthy 6y ago
    Yeah this is the one I ordered: https://www.amazon.de/dp/B0788NPQFV/ https://www.amazon.de/dp/B0788NPQFV/

69 points by nikodunk 6y ago

The virtual monitors feature is niche but very useful when you need it. It is useful for screensharing when you don't have a spare monitor to use but want to arrange a couple of windows. It is so useful that people by dedicated hardware to convince their system to give them another monitor. (HDMI dummy plugs)

foobar33333 6y ago
Its useful for steamvr too which shows you your monitors so a dummy monitor gives you an extra monitor in vr
samus 6y ago
Is is about showing only a certain section of the screen where you have arranged those windows, instead of all of it?

rektide 6y ago

This is one of the sort-of-frustrating as-a-user things about Wayland to me, that every compositor (nee window manager) has to implement capabilities like this for themselves, where-as in X, there was common tooling. And they'll all have different userland tools to use these capabilities. here[1] for example is wlroots/sway implementing headless. That said, the implementations are great, & really show how much Linux has progressed. For a while it wasn't possible (for some reason I wasn't having good luck with either mdi or dp dummy plugs on my type-c only laptop), but I'm really looking forward to using one laptop as a virtual desktop for another desktop, & this work is core to that effort. I like a lot that Gnome was super smart & made outputting a virtual monitor as a PipeWire stream built in!! Smart easy win to make screen capturing even easier. Edit: at my posting rate-limit, so tacking this on, especially to @spivak, I like the diversity a lot, yes. But I still would like to see a situation other than gnome having it's own tooling to configure virtual monitors, wlroots having it's own, kde having it's own. Is this just an insufficienct protocolization problem right now? Are there wayland protocols to do things like change a monitor's resolution? Or to change the mouse speed? I think of Wayland protocols as more between a running app and the compositor, which has all been nicely modularized & protocolized. But I don't understand what if any effort has been made to find a common ground to expose user tooling. It feels like they all have their own suite of command line utilities. Swaymsg in sway, for example. Whatever this virtual monitor tool gnome has. How do we begin to modularize these control interfaces? [1] https://github.com/swaywm/wlroots/commits/master/backend/headless https://github.com/swaywm/wlroots/commits/master/backend/hea...

neolog 6y ago
There could be another library providing these common utilities, which multiple window managers could use.
- zbuf 6y ago
  Is there a library providing these common utilities, which multiple window managers could use?
  - tobasq 6y ago
    Yes, wlroots is such a library.
  - akvadrako 6y ago
    Most wayland features implemented by a plurality of compositors are in the wlroots library. This feature probably isn't in a library though since it's from Gnome.
- sprash 6y ago
  Or it could be part of the Wayland protocol from the get go sparing everyone of major headaches. At some point you arrive at a core functionality resembling X11 and you went full circle breaking everybody's workflow and tooling in the process for no reason other than severe NIHS.
  - mixedCase 6y ago
    Have you considered that maybe it was not done just to spite you and break your workflow? Or that maybe it does have something to do with having a maintainable implementation that doesn't work under assumptions that stopped being valid 20 years ago which make modern usecases extremely hard or impossible to support? And that indeed, the protocol has been growing and new standards have been in development concurrently with X.org maintenance in order to have a smooth transition? You're proposing that having everything ready from the get go would be much better, but that goes against pretty much every principle we know about designing large, complex systems, where BUFD results in huge messes that don't conform to reality, and can never do so, unlike a minimalist protocol that grows over time with careful approaches.

hollander 6y ago

ELI5 please. What is a headless native back end? These articles seem to be written for people who already know that it exists and what it is. How does that virtual monitor work?

AceJohnny2 6y ago
Desktop environments like Gnome assume the hardware on the machine they're running on is all the displays they'll ever have to deal with. "Headless" means there is no display (the "head" of the computer) connected to the machine. This update allows Gnome to use virtual monitors.

deanclatworthy 6y ago

This is fantastic. I have a box in the corner with no display attached and wasn’t able to RDP/VNC etc into it as there was no real display. I had mixed results with an abandoned virtual display package and ended up purchasing a tiny HDMI thing that plugs in the back and emulates a real display.

haldean 6y ago
Do you have a link for the HDMI dongle thing?
- deanclatworthy 6y ago
  Yeah this is the one I ordered: https://www.amazon.de/dp/B0788NPQFV/ https://www.amazon.de/dp/B0788NPQFV/