Re: questions and sundry gripes about X11 multihead (it's a rant)

Brent Busby posted on Mon, 30 Dec 2013 10:34:41 -0600 as excerpted:

> On Mon, 30 Dec 2013, Duncan wrote:
>=20
>> First to address randr.  I believe a lot there depends upon the
>> flexibility and configurability of your window manager.
>=20
> I did read about a window manager called Awesome that's supposed to be
> more multihead-aware than any other, including specific support for
> Zaphod mode (if you can get your card's video driver to do it at all).

Indeed.  I've seen some very good reviews of awesome as well. =3D:^)

> That brings up an interesting possibility:  Since I'd heard everywhere
> that basically RandR has supplanted Xinerama, I have my system compiled
> globally with USE=3D-xinerama.  Does this mean that if I turn USE=3Dxin=
erama
> on, I may be able to get window placement to behave?

Definitely so (tho of course USE=3Dxinerama behavior, as with any USE fla=
g,=20
will be somewhat package dependent).

USE=3Dxinerama doesn't necessarily refer to xinerama itself, but rather t=
o=20
the general family of protocol extensions it introduced, many of which=20
survive the deprecation/demise of xinerama itself.

Things like per-monitor placement are part of those extensions, and are=20
still enabled by USE=3Dxinerama even when it's randr or something else=20
providing the actual multi-monitor framework in X.

So I'd definitely try it.

If you list the output of equery hasuse xinerama, it's likely that=20
various people can fill in the blanks of what its effect is for each=20
package.  Here's the packages I have installed here with that flag:

equery h xinerama
 * Searching for USE flag xinerama ...=20
[IP-] [  ] dev-qt/qtgui-4.8.5-r1:4
[IP-] [  ] media-libs/libsdl-1.2.15-r4:0
[IP-] [  ] media-video/mplayer2-2.0_p20130428-r1:0
[IP-] [  ] x11-apps/xdpyinfo-1.3.1:0
[IP-] [  ] x11-libs/gtk+-2.24.22:2

qtgui, as I said, controls kwin and plasma-desktop behavior as well, as=20
might be expected since they're obviously multi-monitor sensitive and are=
=20
qt-based.

libsdl will likely control the full-screen behavior of various games,=20
anything based on sdl.  Here, it controls dosbox.  There's a lot of other=
=20
packages I have here depending on libsdl, including gegl (gimp), vlc,=20
ffmpeg and others (grub2?  I wonder what /it/ does with sdl?), but I=20
don't believe they all use sdl for full-screen display, so the flag=20
likely has little/no effect on some of them.  (For vlc, the qt-based=20
front-end is the default if built, while I suspect svlc is the sdl=20
variant, so the libsdl xinerama USE flag probably affects only svlc.)

mplayer2... I don't know, as I only use it thru frontends like (qt-based)=
=20
smplayer2.

xdpyinfo just prints display info, so all USE=3Dxinerama could do for it =
is=20
add a bit more info there.

gtk+-2, I'd guess that affects fullscreen for all my gtk-2 based apps,=20
primarily firefox and claws-mail.  (I run pan too, but it doesn't have a=20
built-in fullscreen option.)

> I'm still facing
> driver issues with the open source radeon driver, but this could at
> least be an answer to the window/desktop management problem (e.g.,
> maximizing windows fullscreen to just one monitor).

I'm running radeon here, too, generally ~amd64 but with a current (3.13-
rcX+) kernel, TURKS hardware (Radeon hd6670 or 6770 IIRC, neither dmesg=20
nor the xorg log seem to give the model number, only TURKS, these days).

I've been quite happy with it altho I don't do a lot of gaming.  The=20
triple outputs are very nice, as I'm running 3 @ 1920x1080 stacked for=20
1920x3240.  It's really something seeing kwin's cube or globe multi-
desktop effect on that, when two of them are 42-inch monitors that=20
stacked together fill practically an entire wall!

(The third monitor is actually off to the side as the two big monitors=20
take up the entire wall in front of me.  It runs my superkaramba theme=20
with all sorts of system performance monitors, as seen in the screenshot=20
linked earlier.  I logically stack, however, to avoid the "L" effect you=20
mentioned.  Took a few days to get used to, mainly being aware that if I=20
can't find the pointer it might be on the third screen above/off-to-the-
side since nothing goes there but superkaramba and I wasn't used to=20
looking there, but it's working well for me now.)

--=20
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman