Re: [gentoo-user] Re: Wayland - too early to try?

[Mick]

On Tuesday 11 Jul 2017 22:27:03 Mart Raudsepp wrote:
> Random information dump on the subject.
>
> Wayland is no program, it is a protocol, that's it. dev-libs/wayland is
> essentially a helper library to speak that IPC protocol.
>
> The window manager has to be the compositor and other things as well
> and do the input handling, window drawing, screenshot support, screen
> capture support, etc etc.
> Random programs can not take screenshots, listen to keys (think global
> keys, e.g outside desktop shortcuts/push2talk voip) without some
> protocol between the WM and the program. The Xorg programs for that
> essentially make use of Xorg design security issues to do stuff like
> take screenshots (random program can see your whole desktop screen with
> Xorg), listen to input (keyloggers are trivial with Xorg), etc.
> There are some standardization efforts going on between the desktop in
> various areas of this, to define wayland protocols to more securely
> support these things for applications. In some areas things are still
> lacking.
>
> To detect native wayland vs Xwayland or Xorg I like to use xprop.
> Running that command and clicking it on a window will give information
> about that window IFF it's using Xwayland or your whole session is in
> Xorg.
> But if you are still using Xorg, then you'll have a /usr/bin/X running.
> There is no X running with a wayland WM, just Xwayland at most for
> programs that don't support wayland natively.
> Xwayland is a rootless X server to run on top of a wayland supporting
> compositor. It's conceptually the same like Xquartz or Xming to run X11
> clients in some other environment.
>
> Wayland strives towards the "every frame is perfect" mantra. It is very
> hard for toolkits and other things to draw things halfway on monitor
> scan-out, so things like tearing are rather hard to accomplish, albeit
> possible still in certain situations.
>
> With wayland your programs need to do all the drawing themselves, which
> actually means often pure software rendering, but thanks to the
> smoothness of "every frame is perfect", it'll feel faster on your
> common system. You don't have RENDER extension to do some acceleration
> like you do in Xorg with many toolkits knowing about X RENDER (cairo in
> the gtk+ world). To get hardware acceleration, the toolkit itself needs
> to be able to use OpenGL (full or GLES), Vulkan, or similar. GTK+ 4
> will be able to do both. Games typically already use OpenGL or Vulkan
> and if they run natively on Wayland, they are still accelerated, often
> with some things out of the way compared to Xorg. Programs that don't
> run natively and end up using Xwayland are also accelerated via RENDER,
> as Xwayland makes use of GLAMOR, which implements RENDER in the
> (Xwayland rootless) X server on top of OpenGL. But as said, in practice
> things are fast and smooth already as-is, even if software rendering.
>
> One caveat of Wayland is that if the WM/compositor crashes, your whole
> graphical session dies, while with Xorg the WM typically just restarts
> and for the session to die, Xorg itself would have to die (and that's
> been ironed out over the decades to very rarely do).
>
> GNOME is indeed one of the leaders in adoption and implementing various
> extra features on top of it (even middle-click PRIMARY paste,
> seriously). EFL is probably another, and I think plasma is getting
> there. And then you have the dedicated wayland compositors like Sway (a
> i3-compatible approach). I bet there are something similar openbox-like
> out there as well, but openbox itself definitely won't work, as it'd
> have to be the compositor and not talk libX11..
>
>
> HTH,
> but probably you should have just googled ;)
>
>
> Mart

Thank you very much for a comprehensive information chapter on Wayland!  :-)

Clearly I run Xorg:

 4418 ?        SLsl   0:00 /usr/sbin/lightdm
 4427 tty7     Ssl+   1:00  \_ /usr/bin/X :0 -seat seat0 -auth 
/var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch

xprop does not reveal wayland anywhere either.

I copied /usr/share/xsessions/enlightenment.desktop to /usr/share/wayland-
sessions/ and tried to select it in LightDM.  Unfortunately LightDM returns me 
back to the login page.  I don't know if this is a result of LightDM not being 
compatible with Wayland and friends, or if I need to install some other 
package in addition to what has been emerged already.  
-- 
Regards,
Mick