Re: Re: Controlling displays on a multi head system
Many thanks for responding to my query. Let me try to clear up the
ambiguities you raise by expanding the explanation of my problem.
I want to present images on two monitors that show only objects that my
program writes to the two screens. (These will be used for visual
science experiments in which one eye receives stimuli from one screen
and the other eye from the other screen.) My program uses low level
code, e.g. Xlib primitives like XOpenDisplay(), to handle xorg, which I
thought would give me a clean interface to the displays. However, when
I use, for instance, the Gnome desktop for my console on a third
monitor, I get panels at the top and bottom of the screens of all three
monitors when X boots. I can suppress the panels on the two secondary
monitors (the ones my program uses), but when my program displays a
window on those monitors (which I intend to occupy the whole screen),
the window is capped by a header. That is what I want to avoid, and
really I would like not to have the panels and background of the desktop
displayed on those monitors, though I can handle that.
It appears, then, that xorg is enforcing protocols of the window
manager, or allowing the window manager to enforce its protocols, on
each window created, not only in the console window. Something in the
environment has changed since I last worked with this program a number
of years ago, running it under the Mandrake os at the time: A desktop
never appeared then on the secondary monitors and there never was an
application header displayed when my program created a window. It
seems, then, that either X applies to all screens the protocols
requested for the console or that the window manager knows about the
secondary screens and has negotiated with X to handle them in the same
way it does the console.
I'll very much appreciate you ideas about all of this or suggestions
about how I might pursue a resolution.
> I'm not sure if I understood your goals correctly.
> Do you want...
> a) the "booting" splash screen outputs in just one of your displays
> or you meant
> b) once the system boots and your desktop environment loads you want to
> control what screens holds the main data?
> As for "unadorned" you meant "no icons, just background image/solid
> desktop"? :-?