Bug 407 - Function glTransformFeedbackVaryings incorrectly passes argument
Summary: Function glTransformFeedbackVaryings incorrectly passes argument
Alias: None
Product: Jogl
Classification: JogAmp
Component: opengl (show other bugs)
Version: 2
Hardware: All windows
: P3 major
Assignee: Sven Gothel
Depends on:
Reported: 2010-08-18 14:40 CEST by mateushek
Modified: 2011-02-01 18:09 CET (History)
0 users

See Also:
Type: ---
SCM Refs:
f01d00bb62b75a9e0c4d2926be7e02449a271de6 6f396500e7f595584c2048cebd553b863c90b3c5
Workaround: ---

jUnit4 test of the bug (3.78 KB, application/octet-stream)
2010-08-18 14:40 CEST, mateushek
jUnit4 test of the bug (corrected) (3.59 KB, text/plain)
2010-08-18 14:51 CEST, mateushek

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Description mateushek 2010-08-18 14:40:48 CEST
Created attachment 150 [details]
jUnit4 test of the bug

Bug in method: void glTransformFeedbackVaryings(int program, int count, String[] locations, int bufferMode); 

Method usage in attached jUnit test.

GL profile version: 3 core
JOGL version: jogl-b158-2010-08-13_11-02-01

Offending behavior: 
On Windows the method results in shader linking failure. It seems to be incorrectly passing the argument "locations". 
Expected behavior is that when the specified location name(s) is(are) proper then the linking of shader passes, and when the location(s) is(are) improper then the message in gl info log contains the given name(s).
On Windows (32bit) however the gl info log contains random characters in place where the location name is expected.

Everything works fine on Linux.
Also native C++ code works fine on the same Windows system.
Comment 1 mateushek 2010-08-18 14:49:28 CEST
Comment on attachment 150 [details]
jUnit4 test of the bug

wrong imports present
Comment 2 mateushek 2010-08-18 14:51:02 CEST
Created attachment 151 [details]
jUnit4 test of the bug (corrected)
Comment 3 Sven Gothel 2010-08-23 20:02:00 CEST
1st of all - thx for the test case.

I have changed the test case a bit .. and I can reproduce the bug under windows.

Linux - AMD/ATI:

Vertex shader(s) failed to link, no fragment shader(s) defined.

Linux - NVIDIA:

Link info
error: Varying (named PPPosition) specified but not present in the program object.

Windows7 64bit - NVIDIA:

Link info
error: Varying (named ??osition) specified but not present in the program object.

Link info
error: Varying (named ^N) specified but not present in the program object.

So I assume that the glTransformFeedbackVaryings mapping doesn't work,
probably it's about the char type usage, ie unicode etc.
Comment 4 Sven Gothel 2010-08-23 21:17:07 CEST
Tested on windows with skipping releasing the temporary memory,
which holds the array of strings (array=malloc(); GetUTFChars() / ReleaseUTFChars() / free()).

This 'works' ..

It seems that the NV driver executes the glTransformFeedbackVaryings()
out of order, ie access the string array after returning the call.
Since we release the temp memory right away, this will cause the observed issue.

Trying with new 258.96_notebook_winvista_win7_64bit_international_whql.exe driver .. same thing.
Comment 6 Sven Gothel 2010-11-22 18:28:55 CET
linux nvidia: ok
windows amd: ok

windows nvidia (notebook 258.96): failure (ok test)
windows nvidia (notebook 260.99): failure (ok test)

reduce priority 1 level, 
since this is a driver bug.

Refined the test case a bit
Comment 7 Sven Gothel 2011-02-01 18:09:59 CET
The current unit test don't show any more failures.
This must have been 'solved' in the NV drivers, I guess.



I also tested NV/Win7 manually, works as well.