Graphical Environments & Desktops • Re: Do Wayland Programs Require a Wayland DE?

Do X and Wayland run as system services?

Maybe, and no. An Xserver may be started by init if you use it for your display manager, or it may be started per-user after login (e.g. 'startx' from a TTY).
Wayland doesn't "run" at all, it's just a protocol specification. The closest you get to a wayland "server" is the compositor, of which there are several to choose from.

anything that uses X is actually using an X layer (facade) on top of Wayland?

Applications trying to use X APIs will be run on xwayland. For simplicity, consider it a minimal user-mode Xserver that draws to / gets input from your wayland compositor.
Xwayland supports most features of a real Xserver (and so should be indistinguishable from the application's POV), with the notable exception of native networking.

does this layer have problems/bugs (compared to regular X) such that pursuing as many direct Wayland options as possible is best.

There are no major problems with xwayland ATM, AFAIK. That's based on my experience on Gentoo with bleeding-edge KDE/kwin, so YMMV depending on which wayland compositor and version thereof you use.

I installed Debian 12 and I think that it runs Wayland.

That depends on which DE you installed, and what kind of session you selected at login.

should I prefer a Wayland Desktop Environment and Wayland apps and limit use of X DEs and apps?

You should use whichever you like, whichever provides the features you use, or whichever is best supported by your DE and applications. If a wayland session is the default for your DE, that's likely where most development effort is focused and where any bugs will be squashed quickest.

Does the X-layer on top of Wayland have bug or performance issues?

All software has bugs. Xwayland should perform as well as native X, if it doesn't, file a bug report.

Do Linux applications use Wayland through their respective GUI toolkit e.g. Qt, GTK?

Yes, usually. Depends on the application.

Most toolkits currently support both wayland and X, which they use depends on what kind of session they are launched in and what environment variables (DISPLAY / WAYLAND_DISPLAY etc.) are set.
One can force xwayland on a per-application basis (by setting e.g. GDK_BACKEND, QT_QPA_PLATFORM), even if the toolkit supports wayland natively and is running in a wayland session. The reverse is not the case, as X lacks a wayland compatibility layer.

Can Linux apps use Wayland directly?

Also yes, though most do not because they don't need to. The most common exceptions right now are applications that do high-performance video decoding or screen-sharing.

I don't think that OpenBox uses Wayland. Could an application that I start from an OpenBox DE still use Wayland if it's build to use Wayland?

If you are running in an X session, there will be no wayland compositor and no wayland support. Most applications will detect this and fall back to X.

Statistics: Posted by steve_v — 2024-11-21 04:42

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