From: Axel Kohlmeyer (akohlmey_at_gmail.com)
Date: Mon Jul 25 2011 - 03:48:10 CDT

2011/7/23 AB <albumns_at_hotmail.com>:
> Hello:
>    I am wondering how to generate transparent figures in VMD? it seems that
> we usually get white background figures when we render. And how to define

the background color is determined by whatever you set as background color.

a transparent background is difficult for raytracing tools, as they consider
the environment that you want to remove when calculating the individual pixels.

the straightforward way to deal with this is what is called
greenscreen/bluescreen
in movies: i.e. pick an unusual color that doesn't show up elsewhere
in the picture
and then convert that color to transparency in an image editor (gimp,
photoshop, etc.).

> the size? I would like to get a large size rather than the computer screen
> size.

you can modify the comand line for the renderer any which way you want.
if you use an external rendering command, VMD will by default pass on
the current screen dimensions, but you can change those any which way
to like. please make sure, that you maintain the aspect ratio, or else your
image will be distorted. for more details consult the VMD users guide.

cheers,
     axel.

> Thank you very much.

-- 
Dr. Axel Kohlmeyer
akohlmey_at_gmail.com  http://goo.gl/1wk0
Institute for Computational Molecular Science
Temple University, Philadelphia PA, USA.