[SOLVED] openbox margins with dual monitors

Question

Hi community,
I have stumbled to a nasty problem on my first incursion to dual monitors in openbox.
I'm using xrandr with this command (which works just fine BTW):
xrandr --output LVDS --mode 1280x800 --primary --output VGA-0 --mode 1280x1024_60.00 --gamma 1.0:1.4:0.85 --right-of LVDS
and have set a Virtual screen in xorg.conf of 2560 x 1024 pixels.
But, my laptop monitor only handles 1280x800, while my external LCD monitor has 1280x1024, so there is a virtual area under my laptop screen which i'm not using, but i dont really care about that.
The problem is that when I'm setting screen margins, so that maximized windows will respect the panels in the bottom (tint2), in rc.xml (or by obconf) the margins are applied to the virtual screen and only are practical on the external monitor wich has more pixel height.
I'm really missing some kind of per monitor margin settings in openbox, maybe there is and i haven't found it? It makes me wonder because openbox can maximize windows to a single monitor, even if the whole layout it's treated like a virtual screen, so it has some way of distinguishing between them.
I would appreciate any suggestions, thanks.
Last edited by andreamer (2010-07-26 18:32:15)

Answer 1

TL;DR - I'm not aware of any acceptable solution at the moment.
Basically, what you're having problems with, is the "dead area." It can really be quite a pain in the butt if window managers or other screen aware applications don't anticipate it properly. To my knowledge, Openbox doesn't support margins on a monitor-by-monitor basis. In reality, you shouldn't need to be setting margins anyway. Tint2 should be reporting itself as a taskbar, and Openbox should be respecting that.
I have dead area too, with multiple monitors, and Openbox respects both of the KDE taskbars I have running (one on each monitor). (I use KDE and simply replaced Kwin with Openbox.) This tells me that tint2 should be able to cooperate with Openbox. I remember trying tint2 a while ago, and didn't fine it adequate in a dual monitor environment (it was probably a year ago or so). tint2 would need to be setting the _NET_WM_STRUT_PARTIAL hint, and I'm not sure if it is (or if it's doing it properly). See http://standards.freedesktop.org/wm-spe … #id2507618
Also, I do know that the developer for Openbox recently got a dual monitor setup, and she's been adding additional support for dual monitors a little at a time. Hopefully with 3.5, there will be a lot more support. (Margin support for multiple monitors would be great, because it could be a good utility knife for applications that don't care about multi-monitors setups and don't set the proper hints.)
If you're capable of modifying tint2, my course of action would be to try something that works (like the KDE taskbars) and record the hints being set there. Then compare them with tint2 and try to mirror KDE's setup. (If you're a programming lacking experience with X and related nonsense, I'd be more than willing to offer what guidance I have.)
Also, I developed a panel myself (and got pretty far along) using the PyGTK toolkit... But I can't remember if I solved this problem or not. I'll try to check it out and get back to you. (I got as far as implementing a widget system that includes a task list, system tray, clock, menus... It just isn't polished very well. My original intention was for it to be a more robust PyPanel with dual monitor support.)
Last edited by BurntSushi (2010-07-24 22:46:23)