From: John Stone (johns_at_ks.uiuc.edu)
Date: Fri May 11 2001 - 13:08:34 CDT

Dear Timm, VMD-L,
  It is not presently possible to render surface slices as you
describe, although this could be a _very_ useful feature as you
pointo out. The closest you can get to having cutting planes in
VMD at this moment is to use the "MSMS" surface (have to download
MSMS from scripps.edu) and then toggle on the "all atoms" flag.
This gives you a sort of cutaway view, but may or may not be
what you had in mind. POV-Ray and other ray tracing programs
don't really need "clipping planes" as a fundamental part of their
rendering process, this is a constraint that Z-buffer renderers such
as OpenGL are limited to. We didn't implement clipping planes in
the external renderers because their inclusion in VMD (to date) has
been solely by necessity due to the fact that GL and OpenGL are
both Z-buffer renderers. We have thought about what we'd need to do
to actually add in support for arbitrary clip planes, but haven't
gotten to implementing such a feature yet. This might be something
we do for VMD 2.0, but is unlikely to get done in the next few months,
as we've got a huge plate of new features we're already working on
implementing.

Let us know if there are more questions on these topics.

Thanks,
  John Stone
  vmd_at_ks.uiuc.edu

On Tue, May 08, 2001 at 02:44:28PM +0200, Timm Essigke wrote:
> Dear VMD-L,
>
> is it possible to render only slices of a surface? I would like to
> represent the surface of a protein by a line without volume.
> With the near and far clip it is possible, but I want to show the inside
> of the protein at the same time without clipping. PovRay (for raytracing
> of the figure later) ignores the clipping of VMD anyway (a bug?).
> Is it e.g. possible to render a surface (slice), save it to a file and
> load it afterwards?
> This would allow some hand editing of the surface file. Is there a
> method to load MSMS surfaces from a file?
>
> A selection using a x,y,z-range results in a surface of the atoms in
> this range, but not in this part of the protein surface.
>
> Any help appreciated.
>
> Thanks in advance!
>
> Timm

-- 
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