From: John Stone (
Date: Fri Oct 29 2004 - 19:08:40 CDT

  In order to use the "snapshot" display device, you _must_ have
an active OpenGL context. If you attempt to use snapshot without
an OpenGL context, you'll get zero-length images as you've discovered.
You can use "render TachyonInternal" to get images when you have no
active OpenGL display. Let me know if you need any help getting that
running. Tachyon outputs Targa files by default..

  John Stone

On Fri, Oct 29, 2004 at 05:20:05PM -0400, Osmany Guirola Cruz wrote:
> Hi
> I need a script for my web server....
> the idea is that a user give me a pdb file and then in the server i should
> give him(her) a animated gift of the pdb rotating around and axes..
> i create a tcl script that do the following
> mol load pdb 1oan.pdb
> set frame 0
> for {set i 0} {$i < 360} {incr i 20} {
> set filename snap.[format "%04d" $frame].rgb
> render snapshot $filename
> incr frame
> rotate y by 20
> }
> then i do in the shell
> %vmd -dispdev none -e commands.tcl
> and all the snap.*.rgb have 0 sizes :-( but when i do all this via
> tkcon works perfect......
> how should i do this ...
> Thanks
> Osmnay

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