VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Wed Jul 12 2006 - 00:07:45 CDT

Marc,
  I don't know what internal geometric primitives Blender supports
other than triangles, but writing an input filter Python script specifically
for VMD (or molecular visualization in general) might be the ticket to
getting a high quality result. The idea would be to write an input filter
that works with high level geometric primitives like the ones VMD uses
internally to draw the spheres/cylinders/splines/surfaces that make up the
molecular scene. Similarly, the color and material scheme used could be
made more molecule-friendly by using a scheme in line with what VMD does
internally. Writing a scene in terms of very high level geometry would
do a LOT to reduce file size compared with emitting billions of triangles...

  John

On Wed, Jul 12, 2006 at 12:12:53AM +0200, Marc Baaden wrote:
>
> Hi,
>
> some time ago I was also quite interested in using Blender for the
> final rendering and manipulation of the images and animations. I have
> encountered similar problems as were reported by Ralph and John. I
> remember having tested all VMD export formats, in particular VRML, but
> couldn't get Blender to read them (neither v1.0 or v2) properly.
>
> I came to the conclusion that a good solution could be not to write
> a native fileformat as output, but rather a blender python script that
> would re-generate a similar representation as on screen... unfortunately
> this never really got further than the concept and initial tests phase.
>
> Marc Baaden
>
> >>> John Stone said:
> >>
> >> Hi,
> >> From what I understand, the native Blender .blend file format is
> >> very version specific, changes with every release, and people suggest
> >> you not use it directly. STL is not an appropriate format to use to
> >> import VMD scenes into Blender as you've discovered, it's meant to be
> >> used for Stereolithography, but not much else. What other formats have
> >> you tried importing into Blender? If you know of a file format that
> >> Blender supports well, I'd certainly consider writing an export module
> >> for VMD to better support it. I would have expected Wavefront OBJ
> >> or one of the VRML formats work ok with Blender already.
> >>
> >> Here's a discussion of why the .blend file format isn't documented etc:
> >> http://www.blender.org/forum/viewtopic.php?t=8143&sid=ced5749c0154f65b375
> 01dd929205166
> >>
> >> There is now a "BlendXML" development effort in progress to make a Blender
> >> scene file format that's usable by other software, but as far as I can tell
> >> it's far from finished.
> >>
> >> John Stone
> >> vmd_at_ks.uiuc.edu
> --
> Dr. Marc Baaden - Institut de Biologie Physico-Chimique, Paris
> mailto:baaden_at_smplinux.de - http://www.baaden.ibpc.fr
> FAX: +33 15841 5026 - Tel: +33 15841 5176 ou +33 609 843217
> 

-- 
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