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Jay325
08-13-2013, 09:46 PM
Has anyone successfully cast shadows using emissive lighting and a ground plane from the library/imported ground plane.

I ask because I have been trying for about an hour and I'm not getting solid looking shadows because I don't think the emissive"s can be directed enough to make this happen?

Or if you know a better way to cast shadows without having to use the global lighting please share.

amoncur
08-13-2013, 10:03 PM
You might have to use an actual light instead of an emissive plane. Have you tried that?

andy
08-14-2013, 08:40 PM
You can do it. But it's not very efficient. Remember, the edges of shadows are from focused light. If your light source is large, then the edge will be less in focus.

What you need is a small emissive object, or having the object relatively far away from the object you want a shadow from. Notice if you put an object really close to the ground plane it cases a shadow just fine. Move it far away and it's not sharp at all. You can see the same thing in your office using a post-it note. Near your desk, you get a great shadow. Raise it up to about 18 inches, and unless your light source is a focused light, it'll pretty much be gone. Your light source isn't focused enough.

So if you want a nice sharp shadow, you need a nice sharp light. Focus it either by making it tiny, or put something in front of it with a relatively small hole.

Your render time is about to go through the roof. Play with a Really basic scene just to get it to work, but then do as amoncur suggested and use a light.

Jay325
08-15-2013, 10:31 AM
Thanks guys I'll mess around with some of these ideas, I just think it's a little ridiculous we don't have directional lighting inside bunk yet.

andy
08-15-2013, 05:13 PM
you can change the light type to directional. Also, if you're looking for sharp light in only 1 direction, how about trying a sun?