VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Mon Oct 25 2004 - 13:15:43 CDT

Dominique,
  Interesting, those triangles don't look particularly degenerate to me,
but then POV-Ray has always been quite picky about it's triangles.
One thing you can do to avoid this is to reduce the degree of tessellation
inside VMD. If you're drawing high resolution surfaces, you'll avoid some
of the POV-Ray complaints by having a lower-resolution tessellation of the
same isocontour, molecular surface, etc. Do you get "holes" in the
geometry in the pictures rendered by POV-Ray? You might try using Tachyon
instead, if you have similar problems there, let me know. If you have a
particular file/scene/saved-state that causes your problem, I'd be happy
to take a look at it.

  John Stone
  vmd_at_ks.uiuc.edu

On Mon, Oct 25, 2004 at 02:13:11PM +0200, Dominique Vlieghe wrote:
> Hi,
>
> I have some problems with rendering pictures using povray. Seems that
> part of the image elements are not present in the final output image. I
> also get a lot of errors, being
> ...
> File: E:\dominiv\projects\integrin\structures\test.pov Line: 578
> Warning: Degenerate triangle. Please remove.
> ...
>
>
> Lines at about position 578 look like
>
> ...
> smooth_triangle {
> <-1.8559, -3.5591, 1.4187>,
> <0.5808, 0.8097, -0.0834>,
> <-1.8627, -3.5725, 1.4156>,
> <-0.5809, -0.8097, 0.0835>,
> <-1.8720, -3.5529, 1.4101>,
> <0.1325, 0.9431, -0.3050>
> texture { VMD_mat_1 }
> pigment { color rgbt <0.350,0.350,0.350,0.000> }
> no_shadow
> }
> ...
>
> this one goes wrong, although other smooth_triangle lines go well.
>
> I tested on both linux and windows (I use VMD 1.8.2 and Povray 3.5),
> but to no avail. I used VMD/povray already before, and I don't remember
> to have had problems then. My structures consists mainly of Bonds, VDW
> and NewRibbons Graphical Representations.
>
> Any clues?
>
> Regards,
>
> Dominique
>
>
>
> --
> ------------------------------------------------------------------------
> Save the Hubble petition: http://www.savethehubble.org
> ------------------------------------------------------------------------
> Dominique Vlieghe, Ph.D.,
> Bioinformatics Core, Department for Molecular Biomedical Research (DMBR)
> VIB - Ghent University
> Technologiepark 927, B-9052 Ghent (Zwijnaarde), Belgium
> ------------------------------------------------------------------------
> email: dominique.vlieghe_at_dmbr.ugent.be tel: +32-(0)9-33-13.693
> www: http://www.dmbr.ugent.be/ fax: +32-(0)9-33-13.609
> ------------------------------------------------------------------------
> 

-- 
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