Question about the future of Xorg

[Carsten Haitzler]

On Wed, 11 Jun 2025 12:24:32 -0400 (EDT) Vladimir Dergachev
<volodya at mindspring.com> said:

> 
> On Wed, 11 Jun 2025, Carsten Haitzler wrote:
> 
> > On Wed, 11 Jun 2025 11:06:54 -0400 (EDT) Vladimir Dergachev
> > <volodya at mindspring.com> said:
> >
> >>
> >>
> >> On Wed, 11 Jun 2025, Carsten Haitzler wrote:
> >>>>
> >>>> The only misinformation I see comes from Wayland advocates.
> >>>
> >>> well "the lack of virtual screens in wayland" earlier on in this thread
> >>> was the newest one i can think of here. that is a complete falsity -
> >>> wayland isn't even responsible for this.
> >>
> >> Maybe I am missing something here, but I thought virtual screens in X were
> >> implemented by having a large framebuffer, in GPU memory and having CRTC
> >> send a subset of it to the monitor.
> >
> > it could also be implemented in a fast number of other ways... :) that's
> > how it was implemented, but it can be implemented in different ways. either
> > way it's not implemented by wayland - it "implements" nothing. it's the
> > protocol and libraries to speak that protocol.
> >
> > the implementations are the wl compositors.
> >
> >> So this is done very close to the hardware, and if Wayland does not do
> >> that who does?
> >
> > wayland doesn't do it. it doesn't know or care. it would be sway, gnome
> > shell, kwin etc. etc. - the compositor that might implement this.. and in
> > any way it likes.
> >
> > i would personally never implement it as a massive fb. that's too primitive.
> > i'd just allow panning of windows. i'd keep the wallpaper where it is. my
> > shelve s(panels) where they are. it achieves the same result - making you
> > think you have some massive screen that is bigger than the real one able to
> > host windows that are much bigger. so panning would just be re-rendering
> > the windows on screen with a different offset. keeping other controls like
> > your pager/shelf/whatever overlayed where they are is far more useful than
> > having them panned away and off screen.
> 
> But being primitive is the whole point. The apps render to the large 
> screen as is, and one or more (or none) CRTCs display it on monitors.

the apps don't know or care.

> You don't need the apps to handle the rerendering calls, and the data is 
> always there. For example, you can render a large 8K virtual framebuffer 
> and record it in MP3 file, or view it with x11vnc.

see above. they don't know or care. in a composited world all of a window;'s
pixels exist in another buffer already - the app already rendered them,. the
compositor then renders this again when compositing where the window is meant
to be with whatever transforms/sizes it wants. app doesn't need to know or care.

> Now that I think of it, should not wayland support part of this 
> functionality already - if you have a GPU that is not connected to any 
> physical monitor, there should be a way to create a framebuffer of any 
> size you desire.

as i said - it's a compositor feature if you want this - ie mouse moving to
edge of a screen pans further along in what is some virtual panning area.

> > but... it's not a **WAYLAND** issue. it has zero to do with wayland. it is
> > entirely a feature of a relevant compositor you might use (or not). they
> > could implement it any way they like, if they implement it at all.
> 
> I think it is very much the issue of whatever software (wayland or X, or 
> something else) controls the GPU.

wayland doesn't control it. wayland has no clue how to deal with a gpu. that is
your compositor (or client application). wayland doesn't know how to deal with
a screen output. it has no clue about modes or anything else. that is the
compositor, as i keep repeating. :)

> You should be able to render to a framebuffer of *your* choice, and you 
> should be able to configure CRTCs to use framebuffer of *your* choice.

talk to the compositor devs of your chosen wayland compositor, as i keep
mentioning. wayland has no clue. asking your local bakery for a new hard drive
is not going to help and the more you complain to them that they don't have a
hard drive, the grumpier they will get. wayland is a PROTOCOL. it is a
LANGUAGE. if you went and complained about government policies to the authors
of the oxford english dictionary is not going to get you anywhere... just
because your government may happen to speak english to its citizens (for
example).

> It's really the basic issue of you having control over *your* hardware.
> 
> best
> 
> Vladimir Dergachev
> 
> >
> > it's VERY important to know this distinction as it directly leads to who to
> > complain to or talk to about a feature you want. blaming wayland and
> > complaining here are totally the wrong places to do that. if youw ant gnome
> > shell to have this - talk to gnome shell devs. if you want kde to have it ..
> > complain to kwin devs. if you want sway to have it - talk to sway devs. etc.
> > etc.
> >
> >> best
> >>
> >> Vladimir Dergachev
> >>
> >
> >
> > -- 
> > ------------- Codito, ergo sum - "I code, therefore I am" --------------
> > Carsten Haitzler - raster at rasterman.com
> >
> 


-- 
------------- Codito, ergo sum - "I code, therefore I am" --------------
Carsten Haitzler - raster at rasterman.com