From: Oliver Grant (
Date: Fri Oct 19 2018 - 06:04:37 CDT

Hi all,

I'm using the glowlights.tcl script from John Stone in VMD 1.9.3. I first
render a scene (vmdscene.dat) using tachyon. The tga produced looks good. I
then add glowlights like this:

::GlowLights::new_light { -44 59 5 } white { 0.6 0 0 } 10

::GlowLights::render_scene vmdscene.dat vmdscene_glow.tga

 But the vmdscene_glow.tga only contains light from the glowlight. The
ambient light from tachyon is missing. I also tried:

::GlowLights::append_to_scene vmdscene.dat

followed by this on the command line:

$VMDPATH/lib/tachyon/tachyon_LINUXAMD64 -aasamples 16 -trans_vmd
-mediumshade -format TARGA vmdscene.dat -o vmdscene_glow1.tga
But this still only had the glowlights, and so the rest of the image is
very dark.

Q: Is this a bug on my machine or is this expected behaviour for what I'm
doing? If expected, what can I do to have both ambient lighting and
glowlights rendered?