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sepehr
06-18-2002, 10:49 AM
How may I have a correct shadow if a surface with opacity map,... in 3dmax(4.2)?
Even raytrace shadow just makes a shadow of the edge of the surface not the edge of the texture with opacity map.
I want this for leaves(I have made textures and some surfaces
with opacity map to simulate a tree)

Thanks in advance
Sepehr
Fnkymnky
06-18-2002, 08:24 PM
Are you SURE you set your shadows to "Raytraced"? I just did a test render with an opacity map, and the shadows looked correct...
sepehr
06-19-2002, 07:40 AM
Hmm..
I had found this problem some month ago and have forgotten what exactly it was.
so I tested it again...
Here it is.
The volume light doesn't match with shadow and alpha map...
it doesn't care about Raytrace shadows,it just cares about shadow maps which
don't care about alpha map,...

What should i do?
Is there such a problem in Maya too?
sepehr
06-19-2002, 07:42 AM
Hey I tested the scene with Mental ray 2 and it could render it correctly.
But still I usually render with Max default scanline renderer so the problem
remains...
gaggle
06-20-2002, 09:55 AM
As far as I know it's a limitation of the way MAX handles its volume-light. As you say, volume-light requires shadowmapped lights, and shadowmaps can't see through transparent materials.

Tough luck. I think that's about it.

At least as long as you're using the scanline rendere, as you've already figured out, other renders doesn't have to have this problem.
Iain McFadzen
06-20-2002, 10:24 AM
Go to www.maxplugins.de and look for a plugin which lets raytrace lights cast volumetric shadows. There is definately one there somewhere, I've used it before. It might have been Cebas' FreePyro, or it might have been Sitni Sati's ScatterVL. They are both free so you can just check them both.
Biohazard
06-21-2002, 03:07 AM
For simple images (such as the one you submited), you can tweak the scanline using raytrace, by using 2 lights and far/near attenuation PLUS a projectored map. This won't help for more complicated scenes of course but fits well sometimes.

http://biohazard11.free.fr/exemple02.jpg
JohnHumphries
12-18-2005, 01:56 PM
Hey I tested the scene with Mental ray 2 and it could render it correctly.
But still I usually render with Max default scanline renderer so the problem
remains...

sepehr,

I am trying to do this without luck, do you have an example scene or settings?
sepehr
12-19-2005, 11:26 AM
Hi;
This was posted in 2002.
I really have no idea of what I had done…
I am a Maya user now.
Sorry.
Sepehr
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