View Full Version : Volumetric woes...

06-11-2010, 04:45 PM
I'm trying to get a volumetric lighting effect similar to the one in the LW Manual, where the an object cuts shadows into the light path.
I know I've done it before (a long time ago), but I'm working on a new computer, with a new copy of LW 9.6 (I upgraded from 7.5), and I can't seem to get the object (a text logo) to "cut" the light.
I know I'm probably just not getting the numbers straight (balancing luminocity, opacity, density, etc), so if anyone can help me sort this out, Id be their best friend forever (or at least until I forget about it)...
Darth Brian

06-11-2010, 05:50 PM
Bit hard to say.

Raytrace Shadows is on? :)

06-11-2010, 07:18 PM
Thanks for getting back to me so quickly!
Yes, Raytrace Shadows was the first thing I checked. I'm sure it has to do with the opacity, density, etc. I've tried it with both spot lights and point lights, and still no "cutting" shadows.
Does anyone have a good 'general' template I could start with?
Darth Brian

06-11-2010, 07:56 PM
Perhaps just put up the scene you are working on and can't get it to show up. Strip the scene to the basics if you must...

06-12-2010, 01:38 AM
If you can use Shadow mapped shadows, they render much faster than ray traced volumetrics.

Other than that, I dunno what's wrong with your scene.

Mr Rid
06-12-2010, 03:18 AM
Should work if your volumetric light is set to ray trace, and the object is set to cast shadow. See if it works in a new, simple scene with one light and a sphere or anything.

06-12-2010, 03:27 AM
I'm not afraid of the render times (8-cores are a LOT faster than my old dual 1 GHz machine), and I'm not on a deadline for this.
I think I'm getting closer, but it's slow going to tweak the different parameters without really having a clear understanding of how they all inter-relate...
I'll keep hammering away; I was just hoping someone who uses this a lot had some kind of 'template' that could speed up the learning process.
Thanks for the ideas,
Darth Brian

06-25-2010, 09:27 AM
Does your text have polygon normals facing the light?

07-05-2010, 12:06 PM
Did you check "opacity cast shadow"?