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Bug 449

Summary: Alt-Tab in Fullscreen w/ OpenGL Fails
Product: SDL Reporter: Alec Holowka <zaphire>
Component: videoAssignee: Ryan C. Gordon <icculus>
Status: RESOLVED FIXED QA Contact: Sam Lantinga <slouken>
Severity: major    
Priority: P1    
Version: 1.2.11   
Hardware: x86   
OS: Windows (All)   

Description Alec Holowka 2007-07-03 20:38:33 UTC 
Can be reproduced by running "testgl" in fullscreen. Alt-Tabbing out works, but when trying to Alt-Tab back in, the screen goes black for a moment, then returns to the desktop, "testgl" is still minimized.

Platform: MacBook Pro, Windows XP, Radeon X1600
Has also happened on a regular PC with a widescreen LCD.
Only occurs on certain machines.
Comment 1 Sam Lantinga 2007-07-08 22:30:28 UTC 
I haven't been able to reproduce this on several machines, including a MacBook Pro running Windows Vista, Windows 98 in VMware, and an AMD system running Windows XP.

Can you define WMMSG_DEBUG at the top of SDL_sysevents.c and do a test with these steps:
1. Start testgl -fullscreen
2. Alt tab away
3. Alt tab back (failing)
4. Close testgl
5. Attach the contents of stderr.txt to this bug.

Thanks!
Comment 2 Ryan C. Gordon 2007-07-08 23:50:45 UTC 
Bumping some bugs' priorities to P1 for consideration before the 1.2.12 release (though some may not be resolved for 1.2.12).

--ryan.
Comment 3 Alec Holowka 2007-07-08 23:59:43 UTC 
(In reply to comment #0)

Hmm. I noticed it works fine in some cases on the same Mac Book Pro machine, if it doesn't have my external LCD monitor attached. It seems to occur when running the display on an attached widescreen LCD. My brother has the same model of wide screen LCD on a straight PC, and has the same problems. 

There are a few different things that can happen.

On the widescreen external LCD, when alt-tabbing out, both my brother and I get weird yellow boxes appearing over the screen. Sometimes if I Alt Tab back in, it fails to re-enter the window; and sometimes it will re-enter the window, but there will be a flashing yellow box covering the entire screen. The display seems to be rendering properly with the exception of the epileptic yellowness.

I'll see if I can catch any useful error messages...
Comment 4 Sam Lantinga 2007-07-19 01:13:43 UTC 
Any update on this?
Comment 5 Alec Holowka 2007-07-20 08:29:26 UTC 
Downloaded the newer .12 (was using .11). Recompiled and checked "testgl". It seems to alt-tab fine now.

My project still has yellow flickering when alt-tabbing back in.

If I compile out all frame buffer related code from my project, it can alt-tab fine. So it appears that its not an SDL problem! :)

(In reply to comment #4)
> Any update on this?
> 

(In reply to comment #0)
> Can be reproduced by running "testgl" in fullscreen. Alt-Tabbing out works, but
> when trying to Alt-Tab back in, the screen goes black for a moment, then
> returns to the desktop, "testgl" is still minimized.
> 
> Platform: MacBook Pro, Windows XP, Radeon X1600
> Has also happened on a regular PC with a widescreen LCD.
> Only occurs on certain machines.
>
Comment 6 Ryan C. Gordon 2007-07-20 10:31:38 UTC 
Great, thanks for following up on this!

--ryan.