VMD-L Mailing List

From: John Stone (johns_at_ks.uiuc.edu)
Date: Fri Jun 25 2004 - 18:03:15 CDT

Simon,
  The standard VMD transparency mode is implemented using a "screen door"
technique, which is fast, and runs identically well on all platforms.
There is an enhanced transparency mode available on video cards that
support the GlobalAlphaSUN OpenGL extension, but at present I haven't
come across any PC video cards that do this. The next generation
VMD 1.8.3 code contains OpenGL programmable shading software that
does essentially the same thing that the GlobalAlphaSUN extension does,
so assuming you've got a video card that supports programmable shading,
you'll see markedly better transparency on that hardware. Another option
in the mean time is to use ray tracers like Tachyon (built-in), Raster3D,
or POV-Ray to make your VMD images. They all implement usable
transparency modes and can be used with VMD.

  John Stone
  vmd_at_ks.uiuc.edu

On Fri, Jun 25, 2004 at 10:28:22AM +0200, Simon Latapie wrote:
> Hie,
>
> I have tested the transparency in 1.8.2 VMD (OPENGL) version under
> Windows and Linux (CVS), and it works fine, but it seems to be, well,
> like an old transparency rendering (a bit ugly). Is it normal ? What
> should I do to make "sexier" ?
>
> Thanks for your help,
>
> --
> Garf
> "I'm sorry, I was expecting Shadayim" --Jeff
> Coupling 

-- 
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              
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