VMD-L Mailing List

From: Ralph Jimenez (rjimenez_at_jila.colorado.edu)
Date: Tue Jul 11 2006 - 14:19:30 CDT

John,
  Of the formats that VMD offers, only STL, Wavefront and VRML 1.0 can
be imported by Blender's standard import filters.
   The VRML input sometimes does not work in Blender, and usually only
creates a mesh that is unusable.
  Wavefront and STL do work, but all information on the materials and
lighting are lost on import...this problem might be due to Blender's
import filter.
  With a small protein, 100 residues and cofactor, displaying the
backbone as a cartoon and a few sidechains and cofactor as licorice, the
resolution should be set very low (<50) in which case the STL or OBJ
files are still ~ 100 MB. VMD seems to output quite a few redundant
vertices/edges, and internal points that make the mesh much larger than
necessary. I suspect this issue has to do with the way that VMD exports
the mesh...
   Anyway, it would be great to see the two programs work nicely
together. I'm still learning to use Blender, but the potential is
impressive!
  Ralph

John Stone wrote:
> 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=ced5749c0154f65b37501dd929205166
>
> 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
>
>
> On Tue, Jul 11, 2006 at 09:32:31AM -0600, Ralph Jimenez wrote:
>> It would be great to use VMD's output with an open-source 3D
>> modelling/animation program like Blender (www.blender.org). This program
>> can be used to make some fantastic images and animations, output video
>> files, etc. It would make a nice combination with VMD.
>> I've been able to read .STL files into blender, but the other formats
>> do not work very well. Even with STL, the lights are not imported, and
>> the molecule is imported as one mesh object- no separate
>> cofactor/protein, for example. So my feature request is for VMD to write
>> Blender scene files...
>> I'm curious...has anyone else tried using Blender with VMD?
>>
>> --
>> Ralph Jimenez, Ph.D.
>> JILA/NIST and Department of Chemistry & Biochemistry
>> 440 UCB
>> University of Colorado, Boulder
>> Boulder, CO 80309-0440
>>
>> Tel: (303) 492-8439
>> FAX: (303) 492-5235
>>
>> http://jilawww.colorado.edu/JimenezLab
> 

-- 
Ralph Jimenez, Ph.D.
JILA and Department of Chemistry & Biochemistry
440 UCB
University of Colorado, Boulder
Boulder, CO 80309-0440
Tel: (303) 492-8439
FAX: (303) 492-5235
http://jilawww.colorado.edu/JimenezLab/