screen gamma change and opengl apps on 2nd display/pipe ? - Printable Version

+- IRIX Network Forums (//forums.irixnet.org)
+-- Forum: SGI/MIPS (//forums.irixnet.org/forum-3.html)
+--- Forum: IRIX/Software (//forums.irixnet.org/forum-7.html)
+--- Thread: screen gamma change and opengl apps on 2nd display/pipe ? (/thread-321.html)

---

screen gamma change and opengl apps on 2nd display/pipe ? - radiance - 08-23-2018

Hi all,

I have an Indigo2 MaxImpact in which I added an additional SolidImpact board to serve as a 2nd display driver.
Everything works fine and X runs happily with xinerama across both desktops :)

I am running with the xinerama enabled so I can drag windows across monitors and X thinks I'm running on one big virtual desktop.

I do have 2 issues though :)


Issue 1. Starting OpenGL apps

Since i'm not running multipipe (does'nt support indigo2 I read) and just xinerama, any OpenGL app I start only works on the primary display.
If you move it to the screen area on the secondary monitor the OpenGL window just remains black.
This is normal I assume as the opengl API of the app is initialized on the primary pipe.

If you don't run with xinerama, and have 2 separate desktops, you can run opengl apps on either display by changing your DISPLAY variable to :0.0 or :0.1 as usual, then starting you opengl app(s). Unfortunately this way you can't drag/span normal X windows across the desktop which is very unproductive...
But with xinerama enabled you have just one big virtual display as 0.0 and can't change your DISPLAY variable to indicate to the app to initialize on the secondary pipe.

So does anyone know how to start an OpenGL app on a secondary pipe with xinerama (one big virtual desktop) ? Is it possible at all ?


Issue 2. Display Gamma

Since IRIX still expects old world gamma values for CRT monitors, it's really necessary to set your display gamma when working with modern LCD screens...
I always do this during setup of a system that uses an LCD.
I use the "gamma 1.x" command as root to set a correct value like 1.5, 1.6 etc...

When I do this only my primary screen changes gamma, the secondary screen stays the same.
Again I can't change my DISPLAY variable and then set the gamma for the secondary screen.

Even with xinerama enabled and having 2 separate desktops as :0.0 and :0.1 the gamma command changes the gamma only for the primary display no matter what the DISPLAY variable is, and the gamma command does'nt seem to have any params...

Gamma curves can be changed graphically by dragging curves in the xsetmon tool, but how to represent a specific value like 1.6 as a curve or so is beyond me, there are no markers or scale shown.


Would appreciate some help in this area if anyone knows how to fix my 2 issues ;)

Many thanks,
Terrence

---