VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Fri Jul 09 2004 - 13:09:09 CDT

Simon,
  Which 'stepsize' are you referring to? The step size for the
GUI slider controls or the 'stepsize' parameter in the representation
rendering code DrawMolItemVolume.C?? They are totally different things
but from your email I'm not sure which one you're asking about.

The stepsize for the rendering code is normally set to 1 to generate
full resolution isosurfaces, but while dragging the mouse on the
isovalue slider control, the step size is changed to 2. This reduces
the resolution of the generated isosurface by a factor of 8, with
a commensurate speed increase. I intended for this to be used for
interactive surface visualization while the isovalue slider is being
dragged, but thus far I hadn't seen any reason to provide a Tcl command
or other control to change the isosurface resolution.

If you're thinking of altering the GUI control to have different
minimum stepsize, that's a different matter. Let me know what you
have in mind.

Thanks,
  John Stone
  vmd_at_ks.uiuc.edu

On Thu, Jul 08, 2004 at 11:30:34AM +0200, Simon Latapie wrote:
> Hie,
>
> I have just found that the Isosurface representation had a very useful
> option: stepsize. However, I can't find how to modify it without
> changing the default value in the sources and recompiling VMD.
>
> Is there a Tcl command to modify isosurface stepsize ?
>
> Thanks,
>
> --
> Garf
> "I'm sorry, I was expecting Shadayim" --Jeff
> Coupling 

-- 
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