Bug 36099

Summary:	Vertex distortion bug in the game Xonotic
Product:	Mesa	Reporter:	vand2
Component:	Drivers/Gallium/r300	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED NOTOURBUG	QA Contact:
Severity:	normal
Priority:	medium
Version:	7.10
Hardware:	x86-64 (AMD64)
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:
Attachments:	Distorted vertices or missing triangles 1 Distorted vertices or missing triangles 2

Description vand2 2011-04-09 03:10:14 UTC

In the Mesa versions 7.9.0 - 7.10.2  I get strange triangle
distortion bugs in the game Xonotic. They don't appear in 7.8.2.

http://xwmw.org/misc/triangle_bug_01.jpg
http://xwmw.org/misc/triangle_bug_02.jpg


glxinfo | grep string

server glx vendor string: SGI
server glx version string: 1.2
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
OpenGL vendor string: X.Org R300 Project
OpenGL renderer string: Gallium 0.4 on ATI RV570
OpenGL version string: 2.1 Mesa 7.10.2
OpenGL shading language version string: 1.20


Sebastian H.

Comment 1 vand2 2011-04-09 03:12:00 UTC

Created attachment 45436 [details]
Distorted vertices or missing triangles 1

Comment 2 vand2 2011-04-09 03:12:47 UTC

Created attachment 45437 [details]
Distorted vertices or missing triangles 2

Comment 3 vand2 2011-04-09 05:45:07 UTC

With the current git version the distortions are gone and all looks ok.

glxinfo now:
glxinfo | grep string

server glx vendor string: SGI
server glx version string: 1.2
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
OpenGL vendor string: X.Org R300 Project
OpenGL renderer string: Gallium 0.4 on ATI RV570
OpenGL version string: 2.1 Mesa 7.11-devel (git-d27ff8c)
OpenGL shading language version string: 1.20

Comment 4 Marek Olšák 2011-05-06 05:56:30 UTC

(In reply to comment #3)
> With the current git version the distortions are gone and all looks ok.

Could you possibly bisect the fix, so that we can get it to 7.10.x?

Comment 5 vand2 2011-05-06 09:56:55 UTC

(In reply to comment #4)
> (In reply to comment #3)
> > With the current git version the distortions are gone and all looks ok.
> 
> Could you possibly bisect the fix, so that we can get it to 7.10.x?

Do you mean finding the git commit between 7.8 and 7.9 after which the issue appeared?

Comment 6 Marek Olšák 2011-05-06 10:17:04 UTC

I mean finding the "fix", i.e. when it started to work again.

Comment 7 vand2 2011-05-06 12:20:32 UTC

(In reply to comment #6)
> I mean finding the "fix", i.e. when it started to work again.

Ok, I reverted back to 7.10.2 and libdrm 2.4.23.
but the bug didn't show up as I expected.
But by also reverting the kernel back to 2.6.32 the bug was there again.

So
Mesa 7.10.2 + Kernel 2.6.32 -> bug
Mesa 7.10.2 + Kernel 2.6.38 -> no bug

It seems that it actually was a kernel issue and not a Mesa one.

Comment 8 Marek Olšák 2011-05-06 12:30:05 UTC

OK. I am closing this as NOT-OUR-BUG. r300g in Mesa 7.11 doesn't support old kernels anyway (the last supported kernel is 2.6.34 and even that one contains some bugs AFAIK).

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