VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Wed May 19 2004 - 23:47:05 CDT

Hi Stewart,
  There are actually numerous things that older versions
of Chromium have trouble with. VMD does OpenGL feature
tests at startup to determine whether or not certain OpenGL
extensions are available. I know that a number of the early
versions of Chromium contained bugs in their GLX emulation which
caused problems, unimplemented core OpenGL features, etc. The new
VMD 1.8.2 and 1.8.3 code contain more test code for various extensions,
but the OpenGL shading language feature tests are unlikely to be the
source of the problem. If I were to guess, the problem is most likely
something related to the 3-D texturing code in VMD 1.8.2 and newer.
Looking up the opcode you mentioned shows that in fact that opcode is
actually 3-D texture related. Note that this is a core OpenGL 1.3 feature
and should not be "optional" if the OpenGL version number tests succeed:
glext.h:#define GL_MAX_3D_TEXTURE_SIZE 0x8073
glext.h:#define GL_MAX_3D_TEXTURE_SIZE_EXT 0x8073

In any case, you might have a look at the newer versions of Chromium,
the latest version is version 1.7, released on April 14, 2004:
  http://sourceforge.net/projects/chromium

They may have made progress fixing various of these implementation
limitations since version 1.2. I know that Brian Paul tested VMD 1.8.x
when he worked on Chromium, but I don't know if anyone regularly tests
VMD with the newer versions any more. You might send your note to the
Chromium mailing list to make them aware of the opcode that is causing
trouble.

  John

On Wed, May 19, 2004 at 04:44:24PM -0400, Stewart Dickson wrote:
> Hello,
>
> I have discovered that the vmd-1.8.1 binary will run fine through
> Chromium (cr-1.2), but
> vmd-1.8.2 will not. And I think I know why:
>
> The error I get from 'crserver' [when I send a vmd-1.8.2 OpenGL stream
> to it]
> is as follows:
>
> CR Error(catacomb02:4378): Invalid pname to __numValues: 0x8073
>
> Here is a clue as to what the error means:
> http://chromium.sourceforge.net/doc/packertest.html
> [pack/unpack validation tester]
>
> "What do I do when I get ?
> ...
> CR Error(localhost:12345) Invalid pname to __numValues: 0x034f7
>
> edit crserverlib/get_sizes.py and add the missing token "
>
> In get_sizes.py are tables containing all the OpenGL call keywords
> Chromium supports.
>
> I see among the differences between the vmd-1.8.1 and vmd-1.8.2 source code:
> vmd-1.8.2/src/OpenGLExtensions.C
> vmd-1.8.2/src/OpenGLExtensions.h
> Which do not exist in the vmd-1.8.1 source.
>
> Among the functions defined in OpenGLExtensions.h are "...OpenGL Shading
> Language support..." I know that Chromium up to cr-1.7 does not define
> OpenGL shader language
> calls. The precise token corresponding to 0x8073? I'm not exactly
> sure, but I'm pretty
> sure it is the fact that the native OpenGL headers define shader
> language calls, but CR
> does not. 

-- 
NIH Resource for Macromolecular Modeling and Bioinformatics
Beckman Institute for Advanced Science and Technology
University of Illinois, 405 N. Mathews Ave, Urbana, IL 61801
Email: johns_at_ks.uiuc.edu                 Phone: 217-244-3349              
  WWW: http://www.ks.uiuc.edu/~johns/      Fax: 217-244-6078