Bug 36065

Summary: r600g regression : vertex buffer alignement
Product: Mesa Reporter: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer>
Component: Drivers/Gallium/r600Assignee: Default DRI bug account <dri-devel>
Status: RESOLVED FIXED QA Contact:
Severity: normal    
Priority: medium    
Version: git   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
i915 platform: i915 features:
Attachments: Wrong/Correct rendering
sample app that reproduces the issue

Description Pierre-Eric Pelloux-Prayer 2011-04-07 15:23:43 UTC
I have a simple app using vbo to render models.
The VBO layout is : position (3 float), normal (3 float), color (3 char)

This app was running perfectly until I updated libdrm/mesa to git version.
Now the app still does not have any GL error set (checked with glGetError()), but its rendering is completely wrong.

git-bisect pointed me to this commit :
  "r600g: Request DWORD aligned vertex buffers."

OS : Debian unstable (amd64)
Radeon HD 4850
Comment 1 Pierre-Eric Pelloux-Prayer 2011-04-08 05:02:00 UTC
Here's a few more information, hoping it could help :

From Xorg.0.log :
[KMS] Kernel modesetting enabled.

From glxinfo :
EE r600_pipe.c:430 r600_get_param - r600: unknown param 45
name of display: :0
direct rendering: Yes
OpenGL renderer string: Gallium 0.4 on AMD RV770

From lscpci -v :
VGA compatible controller: ATI Technologies Inc RV770 [Radeon HD 4850] (prog-if 00 [VGA controller])
Comment 2 Pierre-Eric Pelloux-Prayer 2011-04-08 05:03:43 UTC
Created attachment 45415 [details]
Wrong/Correct rendering

On the left : rendering using mesa including the mention commit
On the right : rendering using older mesa OR LIBGL_ALWAYS_SOFTWARE=1
Comment 3 Alex Deucher 2011-04-08 07:42:37 UTC
Can you attach the source to your test app?
Comment 4 Alex Deucher 2011-04-08 07:43:31 UTC
Or find a simple mesa demo or piglit test that exhibits the same issue?
Comment 5 Pierre-Eric Pelloux-Prayer 2011-04-08 08:44:47 UTC
Created attachment 45424 [details]
sample app that reproduces the issue
Comment 6 Marek Olšák 2011-04-08 09:48:55 UTC
Both r300g and r600g are affected. I am working on the fix.
Comment 7 Marek Olšák 2011-04-08 10:36:01 UTC
Fixed with commit a0d154dc1385d92a31dca8e65e50d958bdf6d532. Closing.

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