VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Wed Oct 15 2003 - 13:24:02 CDT

Dear VMD-L,
  I've found the source of the performance problems with the Axes
display on MacOS X. Apple's implementation of gluSphere() combined with
glNewList()/glEndList is VERY VERY slow. I'll skip going into details on
this for now until I've got a solution, but the upshot is that their
implementation of these routines (as a group) runs about 10-20 times slower
than on any other OpenGL implementation I've ever tested. This could be for
any number of reasons, so I can't damn them for it, but it does mean I'm going
to have to change some code in VMD. The Axes are only one particular case
the triggers this performance problem. I hope to have a fix in VMD 1.8.2
that will eliminate this problem in all of the common cases. In all honesty
though, I'm amazed this sequence of calls runs so slowly on MacOS X.
For now, leave Axes turned off and most people will get good rendering
performance from VMD with the Apple's recent OpenGL drivers.

Thanks,
  John Stone
  vmd_at_ks.uiuc.edu

On Tue, Oct 14, 2003 at 02:11:26PM -0400, taeho.kim_at_utoronto.ca wrote:
> Hi
> I am wondering whether the performance of VMD would be affected by a new ver
> of Mac OSX, 10.2.8. Our Mac OSX has been upgraded to 10.2.8 and I realized
> that reading trajectories including rendering seemed much slower on 10.2.8
> than 10.2.6. (i.e. it might take a second to read a frame.) I appreciate any
> information on this. Thanks,
> Taeho 

-- 
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