Xpresent transparent window title bar

[Carsten Haitzler]

On Wed, 07 Feb 2024 05:44:22 +0000 "Guy Rouillier" <guy.rouillier at gmail.com>
said:

> I originally sent this message, and subscribed to receive replies.  
> Carsten Haitzler appears to have replied to this message in a mirror, 
> with a cc to xorg at lists.x.org. I did not receive that reply.  I'm 
> guessing that subscribers only get messages sent "to" the list, and not 
> "cc" the list?  Carsten's full reply is here:
> 
> https://lists.x.org/archives/xorg/2024-February/061540.html
> 
> I don't now the proper protocol for copying text from other messages, 
> but I wanted to respond to the opening comment:
>  > Your question really should be directed at the mate picom etc. developers,
>  > not here unless you want to discuss the general x11 compositing and
>  > rendering pipeline etc. .. so I'll answer from that point of view.
> I believe that the Xpresent extension is not part of picom.  Instead, it 
> is part of xorg itself:
> 
> https://gitlab.freedesktop.org/xorg/lib/libxpresent
> 
> I was informed of this when I initially asked on the Ubuntu MATE forum:
> 
> https://ubuntu-mate.community/t/marco-xpresent-compositor-transparent-title-bars/26968
> 
> Since Xpresent is not a compositor, I'm going to spend a little time 
> seeing if I can figure out how to modify the theme I'm using (YaruOK) to 
> have transparent title bars.  If I can't get that to work, I'll switch 
> to Xrender (which definitely is part of picom, and is a proper 
> compositor.)

Xpresent will not help in having transparent titlebars - it's about either
"vsync events" - ie getting some event on a refresh on a given window/screen
for timing (probably really useful for determining animation timing) or
displaying a final rendered pixmap to a given target window and some
fences/timing etc.

As per my original mail the transparency is a matter of rendering, so I suspect
the xpresent renderer in picom is a bit of red herring here in terms of naming.
As I said - it's not my project so I can't comment beyond that.

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