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Bug 263

Summary: SDL_VIDEO_FULLSCREEN_HEAD not working
Product: SDL Reporter: jussi haverinen <jussih>
Component: videoAssignee: Ryan C. Gordon <icculus>
Status: RESOLVED INVALID QA Contact: Sam Lantinga <slouken>
Severity: normal    
Priority: P2    
Version: 1.2.10   
Hardware: x86   
OS: Linux   

Description jussi haverinen 2006-06-25 16:05:41 UTC 
SDL_VIDEO_FULLSCREEN_HEAD works correctly with value of 1, showing an image only on my television, however with a value of 0, it doesn't display the image only on my monitor, but rather shows it on both screens.  

My setup is nvidia proprietary drivers, Xorg 7 and debian testing.
Comment 1 Sam Lantinga 2006-06-25 16:21:44 UTC 
If it shows the same image on both screens, this is the NVidia drivers mirroring the image to both screens.  Check your NVidia driver documentation to find out how to change that behavior.
Comment 2 jussi haverinen 2006-06-26 07:14:35 UTC 
It shows the image halfway across both screens, not as a clone image (due to the "clone" setting).
Comment 3 Sam Lantinga 2006-06-26 07:33:45 UTC 
Can you add this line to the top of SDL_x11modes.c
#define X11MODES_DEBUG
 .. and show me the output of testvidinfo?
Comment 4 jussi haverinen 2006-06-26 08:40:58 UTC 
(In reply to comment #3)
> Can you add this line to the top of SDL_x11modes.c
> #define X11MODES_DEBUG
>  .. and show me the output of testvidinfo?
> 

I got the subversion version and added the debug line, but I'm not completely sure if testvidinfo used the correct library.

jussi@monet:~/src/SDL/test$ ./testvidinfo 
X11 detected Xinerama:
xinerama 0: 1280x1024+0+0
xinerama 1: 1024x768+1280+0
VidMode modes: (unsorted)
Mode 0: 2304 x 1024 @ 0
Mode 1: 1280 x 1024 @ 75
Mode 2: 2048 x 768 @ 0
Mode 3: 1600 x 600 @ 0
Mode 4: 1280 x 480 @ 0
Xinerama is enabled
VidMode is enabled
X11 video mode list:
        2304x1024
        2048x768
        1600x600
        1280x1024
        1280x480
Video driver: x11
Current display: 2304x1024, 32 bits-per-pixel
        Red Mask = 0x00ff0000
        Green Mask = 0x0000ff00
        Blue Mask = 0x000000ff
Fullscreen video modes:
        2304x1024x32
        2048x768x32
        1600x600x32
        1280x1024x32
        1280x480x32
A window manager is available
Comment 5 Sam Lantinga 2006-06-26 09:04:12 UTC 
(In reply to comment #4)
> I got the subversion version and added the debug line, but I'm not completely
> sure if testvidinfo used the correct library.

You did.  That's very interesting, this shows that the NVidia driver is exposing the dual screen setup as a single double-wide monitor.  Is that what twinview is supposed to be doing?
Comment 6 jussi haverinen 2006-06-26 12:48:23 UTC 
(In reply to comment #5)
> (In reply to comment #4)
> > I got the subversion version and added the debug line, but I'm not completely
> > sure if testvidinfo used the correct library.
> 
> You did.  That's very interesting, this shows that the NVidia driver is
> exposing the dual screen setup as a single double-wide monitor.  Is that what
> twinview is supposed to be doing?
> 

After reading nvnews for a awhile, I think it is what it is supposed to be doing (or it's a feature short).  So I suppose this might best be fixed when nvidia drivers are updated again.
Comment 7 Sam Lantinga 2006-06-27 19:25:28 UTC 
Comment from NVidia:
This is probably because a mode with the right dimensions wasn't
specified.  You'd want to set up a mode like "1280x960,NULL" or
"NULL,1280x960" to turn off one or the other screen.