From: Vermaas, Joshua (
Date: Sat Nov 12 2016 - 16:46:14 CST

Hi Ben,

My understanding is that there isn't a standalone GPU-enabled Tachyon
binary. The tachyon binary you are calling actually comes from John's
independent passion project (,
which was CPU-only. John might have an OptiX variant that can be called
independently, but otherwise you are stuck with whats inside VMD.
Happily though, the most common request (arbitrary resolution) can be
done through a non-interactive VMD session pretty easily.

Basically you set up the view as you like at a smaller resolution but
with the same aspect ratio, and save the VMD visualization state (lets
say state.vmd). This is just a plain Tcl script that tries its hardest
to recreate the scene you've setup (although for whatever reason leaves
the axes as the default). Then you add some things to the end of the script.

axes location off; #Turn off the axes. I wanna see molecules, not 3 arrows
render TachyonLOptiXInternal test.ppm; #Does the actual rendering
exit; #Tell VMD to quit after rendering. Super useful for batch jobs
that otherwise waste node-hours

Then you call this non-interactively from the terminal. The VMD
command-line options are handy for this

vmd -dispdev text -e state.vmd -size 4800 4800

In non-interactive mode, whatever you pass as the argument for size is
the rendered size (in pixels), and is how you can get sizes *greatly* in
excess of you monitor resolution.


On 11/11/2016 11:23 AM, Ben Lowe wrote:
> I would like to render using the GPU-enabled TachyonLOptiXInternal,
> and custom options (such as a high resolution).
> I have managed to do this succesfull for the CPU Tachyon using the
> following command:
> render Tachyon scene.dat
> "/local/scratch/bml1g12/Software/vmd-1.9.2/install/vmd/tachyon_LINUXAMD64
> -aasamples 12 -trans_max_surfaces 1 %s -format TGA -res 846 626 -o
> %s.tga"
> But this relies upon passing the PATH of the executable for the the
> CPU Tachyon (/local/scratch/bml1g12/Software/vmd-1.9.2/install/vmd/tachyon_LINUXAMD6)
> and as I do not know the PATH of the GPU enabled Tachyon, I cannot use
> this for TachyonLOptiXInternal. How can I find the path for the GPU
> enabled tachyon (TachyonLOptiXInternal)?
> Or alternatively, how can I run TachyonLOptiXInternal with options?
> My question seems similar to the unanswered question last year from
> Parker de Waal :
> Kind Regards,
> Ben