[GRASS-dev] nviz compilation problem

[Helena Mitasova]

Glynn,

thanks a lot for your help - I asked our sys admin to check the libGL  
and apparently
the symlinks were the problem again. Just for the record, in case  
somebody has a similar problem
this is what he says:

> I took a closer look at things and noticed that there
> were a few symlinks that pointed at nothing.  Re-installing
> the packages cleared that up -- and the files that appeared
> to be missing were /usr/X11R6/lib64/libGL things.

after that everything compiled just fine and nviz runs great,

Helena

On Jun 28, 2007, at 7:09 AM, Glynn Clements wrote:

>
> Helena Mitasova wrote:
>
>> thank you for your help - removing $(OPENGLLIB) $(OPENGLULIB) from
>> the ogsf/Makefile solved the ogsf compilation problem.
>>
>> The nviz compilation still gives a related error:
>>
>> Errors in:
>> /local/home/helena/grassdev/grass6/visualization/nviz
>>
>> /usr/X11R6/lib64/libGL.a(glxcmds.o)(.text+0x32c1): In function  
>> `glXGetMscRateOML':
>> : undefined reference to `XF86VidModeQueryVersion'
>
> Ick. You should be able to work around this by manually adding
> -lXxf86vm to the definition of OPENGLLIB in Platform.make (once
> configure has generated it).
>
> Unfortunately, it's hard for configure to detect this sort of thing
> when using static libraries.
>
> Linking against a shared library uses the entire library as a
> monolithic entity, and will require any dependencies which the library
> has.
>
> OTOH, linking against a static library only uses the specific object
> files which are actually required to satisfy any unresolved symbols,
> and so only requires any dependencies of those specific object files.
>
> The result is that a test program which uses a single function (e.g.
> one generated by autoconf's AC_CHECK_LIB) will typically have fewer
> dependencies than the real program (e.g. NVIZ).
>
> E.g. a test program linked against -lGL will only require -lXxf86vm if
> it references a function which is defined in glxcmds.o. Currently, the
> test is for glBegin, which will certainly be in a different file (the
> generic gl* functions and the X11-specific glX* functions are largely
> separate), so the test doesn't need -lXxf86vm although NVIZ itself
> does.
>
> We could change the autoconf test to check for e.g. glXCreateContext,
> which is more likely to require that file. But, ultimately, the only
> solution for static libraries is to play "whack-a-mole", continually
> adjusting the tests whenever ATI/nVidia change their OpenGL drivers.
>
> -- 
> Glynn Clements <glynn at gclements.plus.com>