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kylepro88
03-19-2005, 01:08 AM
I am trying to add Photometric lights to light a scene but im having a problem. I want the light to use my lamp object as the reflector to distribute the light, but the light is just going through my light model and shining above it and stuff instead of it containing in the lamp part and shining out the bottom like it should. How do I go about doing this?
Arkon11
03-19-2005, 09:07 PM
I would like to know this aswell.
vrljc
03-20-2005, 05:24 AM
Just curious, which software package are you using? I rarely read about Photometric lights. Is this related to GI?

Also, what kind of lamp have you created? Does it have a lamp shade? Could you post a render of your problem to clarify what you mean?

-jon
Ian Jones
03-20-2005, 11:54 AM
3dsmax photometric lights? Sounds like your lamp has no thickness or the polygons aren't double sided so its a geometry issue. Assuming you understand what a 'surface normal' is, basically light is not being blocked by the single sided polygon because there is no facing surface normal for the renderer to calculate shadows from. To see this happening, make a simple test scene with an omni light inside a sphere primitive and add some extra objects around the sphere and you'll see that the light just goes straight through the sphere and lights the surrounding objects. Now flip the surface normals of the sphere and the light is now blocked. For a simple solution without haveing to modify your geometry, in Max's material editor tick 2 sided in the lamps material.
pokoy
03-20-2005, 02:26 PM
...and make sure the light (or the object) casts shadows...
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