[vtk-developers] extension wrangler

[Jeff Lee]

Moreland, Kenneth wrote:

> The dlopen technique was dissabled because it was proving to be 
> unreliable.  Some of VTK's dashboard tests were continually failing 
> because VTK was being compiled against one OpenGL library (which 
> happened to be static) and the dlopen was openening a shared object 
> library elsewhere.  Thus, it would look like the extension was loaded 
> correctly, but the application would crash if you tried to use any of 
> the functions.
>
What if the dlopen method were only enabled when vtk is built shared?  I 
saw that vtkOpenGLExtensionManagerConfigure.h that does
#define OPENGL_LIBRARIES 
"/usr/lib/libGL.so;-lSM;-lICE;-lSM;-lICE;/usr/X11R6/lib/libX11.so;/usr/X11R6/lib/libXext.so;/usr/X11R6/lib/libX11.so;/usr/X11R6/lib/libXext.so"

If you do dlopen with a null in the first argument, the loader will 
search the libpath (you don't really need to specify).  Is this the kind 
of behavior we should support?  Are there cases when this approach 
yields undesirable results?  This appears to be what glew does.
Regards,
-J

>
> Ultimately we could not figure out a way to ensure that the dlopen 
> tried to open the same library that was already being used. (The 
> problem gets more compilicated when you compile on one machine and run 
> on another.) If someone could solve this problem, then the dlopen 
> method would work just fine.
>
> -Ken
>
>
> -----Original Message-----
> From: vtk-developers-bounces+kmorel=sandia.gov at vtk.org on behalf of 
> Jeff Lee
> Sent: Tue 11/15/2005 12:31 PM
> To: vtk-developers
> Subject: [vtk-developers] extension wrangler
>
> Hi,
> Does anyone know why the extension wrangler in vtk has the fallback
> dlopen technique disabled?  Is there some way this could be fixed for
> systems without glxProcAddressARB functionality?  Is the wrangler meant
> to be a runtime wrangler, or just compile-time?
> Regards,
> Jeff
> _______________________________________________
> vtk-developers mailing list
> vtk-developers at vtk.org
> http://www.vtk.org/mailman/listinfo/vtk-developers
>
>

-- 
Jeff Lee
Senior Software Engineer
Computational Dynamics North America Ltd
21 Lafayette Street, Suite 230
Lebanon NH 03766 USA
fax:   603 643 9994
phone: 603 643 9993 x109
http://www.cd-adapco.com