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sublimationman
01-31-2010, 01:01 AM
I thought I understood volumetric lighting but it's not acting like I thought it should.

I want to make a box and have light shine out the top of the box when viewed from the side as if there were a light or something glowing inside the box.

I first tried with a point light but it lit up objects next to the box as if it shined right through the box it's in. So I tried a spotlight and I am getting closer with it but since it's a round cone and the box is square it's still not quite right and if I spread it out enough to go to the corners of the box it then bleeds through the sides of the box.

Next problem is I wanted the lighting uneven as if it were passing around objects in the box. I figured I would use the turbulence texture in the volumetrics options panel but no matter what settings I try it is not having any effect on the light.

Is there a problem with volumetrics right now? or am I doing something wrong? Is there a better way?

What I am trying to create is kind of like this http://www.jupiterimages.com/Image/royaltyFree/83112704

Any ideas?

Hopper
01-31-2010, 01:16 AM
This might help.

Volumetric Lighting (ftp://ftp.newtek.com/multimedia/movies/w3dw/Volumetric.mov)

toby
01-31-2010, 04:59 PM
A bow will not cast shadows from the inside unless it's double-sided.

The texture options will not create the rays that you want, those are the result of shadows - unless that's the purpose of the "opacity casts shadows" option, I'm not sure.

sublimationman
01-31-2010, 06:24 PM
The box had full structure inside and out. It turns out the key was the "opacity casts shadow" checkbox. I also ended up using an object over the light to get the desired breakup of the beam of light. Not 100% the way I wanted it but good enough for this project.

My main disappointment was it actually cast dark shadows in the air around the volumetric light beam. I ended up using Photoshop to remove the worst of it.

toby
01-31-2010, 06:39 PM
The box had full structure inside and out. It turns out the key was the "opacity casts shadow" checkbox. I also ended up using an object over the light to get the desired breakup of the beam of light. Not 100% the way I wanted it but good enough for this project.

My main disappointment was it actually cast dark shadows in the air around the volumetric light beam. I ended up using Photoshop to remove the worst of it.
Make the shadow object semi-transparent! Seems like you could switch back to the point light for a more realistic look too -

probiner
01-31-2010, 07:55 PM
Gave it a shot. I know, it looks bad :D (ambulence inside?)
Used Crust texture with Position and Rotation animated, for the shadow casting. Opacity Cast Shadow off, in this case.
http://i153.photobucket.com/albums/s202/animatics/Lightwave/box_render.gif

EDIT: lol, by the tme i posted this, the war was over...