View Full Version : Volumetric Lights weird spots

07-11-2013, 07:36 PM
Um . . . I have a scene with a volumetric spot light underneath a box, shining upward. There seem to be rays showing through my object? It's really weird. When I turn volumetrics off, the weird spots go away. And their prominence decrease as I turn down the settings on volumetrics. Any ideas? The surface is double sided, texture map on the color channel. No transparency. The spots seem to move around depending on where the camera is.


07-11-2013, 08:54 PM
Tried switching to shadow maps from raytracing. Still getting weird spots from the volumetrics. Occurs in shadows too, as darker grunge.


07-12-2013, 02:44 AM
Tried making your box sides "thicker"? I vaguely recall a discussion about how volumetric lights can potentially "bleed through" simple double-sided surfaces in some cases instead of treating them as opaque, and that a workaround was to give the "volumetric-light-containing" object's sides real thickness. Vaguely is operative term here, though, sorry I can't be more helpful.

07-12-2013, 09:27 AM
Yeah, I tried several things. I think I will end up just rendering in two passes. One pass with all the objects and no volumetrics, and one with all objects set to matte. Just overlay the volumetric layer in screen mode. I tried it with that second frame and that icky grunge disappeared. So I will test on a couple other frames and go with that.