VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Sun Mar 30 2008 - 15:51:16 CDT

Hi,
  Sorry for the delayed reply on this question, I missed it while
I was out of town at a conference. Figure 6 in the Images and Movies
tutorial was created using POV-Ray 3.x. To get a rendering like this,
one would typically pick one of the shiny materials, but reduce the
"shininess" value in ther Materials window to make the specular highlights
match your desired size. The transparent surface shown in Figure 6 would
have the opacity set to a very low value, perhaps only 0.1. Try that
and render with POV-Ray and see if that gets you what you're after.

Figure 10b uses a very low opacity value, likely around 0.1 or so,
and it is rendered using one of the ray tracers, probably either
Tachyon or POV-Ray. To get transparent surfaces like that, it's often
useful to start with a fairly diffuse material, and then reduce
the opacity value to about 0.1 or 0.2 and then do a test rendering to
see if you get what you want. Since the external rendering programs
all use slightly different shading equations, there's a limit to how
representative what you see in an interactive OpenGL display will be
relative to what you get from the external ray tracers. You may need
to tweak the material values and re-render a couple of times to get
the result you have in mind. My suggestion is to render at a lower
resolution for quick turnaround, and then refine things with a full
resolution rendering as you're getting close to the result you're after.

Cheers,
  John Stone
  vmd_at_ks.uiuc.edu

On Mon, Mar 17, 2008 at 02:17:57PM -0700, Dong Xu wrote:
> Hi,
>
> Could someone let me know the procedures to re-create Figure 10(b) and
> Figure 6 in VMD Images and Movies Tutorial. The tutorial does not elaborate
> them, especially the transparent MSMS water box in Figure 10(b). I tried
> different combinations of Materials, but couldn't get the kind of
> transparency/color to match the figures in the tutorial.
>
> Thanks,
>
> -DX 

-- 
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