[off-list] Re: Xfwm4 / compositor: gray background

[Olivier Fourdan]

> On Wed, 20 May 2015 12:21:03 +0200, Ralf Mardorf wrote:
>>[rocketmouse at archlinux ~]$ cat /var/abs/extra/xfwm4/PKGBUILD
>>[snip]
>>    --enable-compositor \
>>[snip]
>>
>>What is the name of the option that needs to be added?
>
> PPS: Note, the OP is an Arch user and seemingly the compositor is
> enabled by default. Is something else missing?

No, absolutely not, in xfwm4, the compositor can be enabled or
disabled dynamically, you don't even have to rebuild to disable the
compositor in xfwm4 (which is another reason why I do not understand
the suggestion to use a window manager without compositing, simply
turn compositing off in xfwm4 if that's what you want).

So, to summarize, I see the following options:

1. Simple leave xfdesktop running, just disable all icons on the
desktop (no need to rebuild).
    pro: you have all the functionalities, it's a /supported/ xfce
setup - cons: you have xfdesktop running (although I don't think it's
an issue).
2. Disable xfdesktop, but then you would have to also disable
compositing in xfwm4 (ditto, no need to rebuild).
    pro: xfdesktop is not running, which is what you want - cons:
compositing is also gone
3. Use a distribution that enables root pixmap monitoring in xfwm4, I
heard Xubuntu does that.
    pro: it's all built and enabled for you - cons: it's not your
usual distribution
4. Use an alternative window manager
    pro: dunno, depends on that other window manager of your choice -
cons: ditto, depends on what you want/expect
5. Use an alternative standalone compositing manager
    pro: some compositing managers offer more eye-candy and anumations
- cons: ditto, depends on what you want/expect, but some features in
xfwm4 are disabled if compositing is handled by a separate compositing
manager.
6. Rebuild xfwm4 from source
   pro: you get exactly what you want, you may even try git master and
get OpenGL or XPresent support so it's completely tear-free [2] -
cons: it's a tad more complicated, you need to install the devel
packages that don't get installed by default on most distributions.

Now if you choose option #6, to enable root pixmap monitoring, you
have to define MONITOR_ROOT_PIXMAP (see [1]), it's not a configure.sh
option, it's just a "define" in C so you can enable it with:

  $ CFLAGS="$CFLAGS -DMONITOR_ROOT_PIXMAP=1" ./configure --prefix=...
  $ make

or alternatively

  $ ./configure --prefix=...
  $ make "CFLAGS=$CFLAGS -DMONITOR_ROOT_PIXMAP=1"

(note I am not listing the configure options, it's left as an exercise
to the reader).

Cheers,
Olivier

[1] http://git.xfce.org/xfce/xfwm4/tree/src/compositor.c?h=xfce-4.12#n844
[2] except on proprietary NVidia driver