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jasonwestmas
11-05-2006, 03:57 PM
In LW9 I'm trying to use a "spotlight shadow map" on a sasquatch wig while not affecting the surface of the model's skin. I'm using this spotlight shadow map with other lights that cast "Raytraced Shadows." The problem is that the shadow map is creating artifacts on the surface of my model where the "Raytraced Shadow" is. I would have thought that excluding the light that casts the Shadow map from the surface with the "Raytraced Shadows" would also eliminate the effects of the shadow map. It doesn't, the shadow map still effects the Raytraced Shadows even though it was excluded from the surface.

Is this a known Problem??

jasonwestmas
11-05-2006, 04:49 PM
Well, I removed the Sas plugin but the problem still resides. Whether I'm using spotlights or distant lights makes no difference as either. The fact that I have a light in the scene with shadow mapping turned on is just conflicting with the Raytracing. Must be a known issue, something like that must've been noticed by now. I just never had to do it before.

Sensei
11-05-2006, 07:49 PM
IIRC Sas works with just one light type.. It's pixel filter- post-processing effect..

Sensei
11-05-2006, 07:51 PM
Can you attach scene & objects to reproduce effect?

jasonwestmas
11-05-2006, 09:25 PM
Well, I'm pretty sure Sas has nothing to do with the artifacts. It seems that the shadow maps simply don't work well with the raytraced shadows even though both lights are not affecting the same objects. I'll post the files if you think it would help. I was just wondering if this was a known problem.

jasonwestmas
11-05-2006, 09:43 PM
Can you tell me more about what IIRC Sas is about and how it works?

SplineGod
11-06-2006, 03:03 AM
It might be the resolution of your shadow maps.
If you increase the cone angle youll need higher rez shadow maps.

Wolvy_UK
11-06-2006, 07:26 AM
IIRC = If I recall correctly. :)

jasonwestmas
11-06-2006, 09:27 AM
Here are my tests, one set with everything turned on, the other with everything turned off except the lights. As you can see the raytraced shadow is messed up now with the shadow map turned on. It doesn't make sense to me because the skin of the model has been excluded from the Shadow map spotlight all together unless there is a bug that is indirectly causing the conflict between the shadow map and the raytraced shadows of the other light. The shadow map has been set up to only affect the hair. The sphere is used to cast the shadow onto the Sas Hair.

Btw the shadow for the hair is done with geometry and a raytraced shadow. In the second set I turned off that shadow. The Shadow map is set for 4000 pixels with a cone angle of 30 (Default Angle) I can't really increase that much without busting my Ram Capacity.

Sensei
11-06-2006, 09:39 AM
Do you have polygonal mode or sub-patched? It looks like sub-patched, but better ask..
Check whether you have some N-gons both 1-2 or more than 5 vertices.. If you have them try tripling.. Just for test.. For one person tripling worked in similar problem with shadows month ago on forums..
What camera are you using, I suppose so Classic camera if you're using SasQuatch (which doesn't work with any other camera types; currently only TrueHair works with any camera types)..

jasonwestmas
11-06-2006, 09:47 AM
Do you have polygonal mode or sub-patched? It looks like sub-patched, but better ask..
Check whether you have some N-gons both 1-2 or more than 5 vertices.. If you have them try tripling.. Just for test.. For one person tripling worked in similar problem with shadows month ago on forums..
What camera are you using, I suppose so Classic camera if you're using SasQuatch (which doesn't work with any other camera types; currently only TrueHair works with any camera types)..

Hi Sensei,

1) Subpatch

2) No Ngons obviously

3) Classic Camera

jesusguijarro
11-06-2006, 10:53 AM
Are you using specular nodes? If so, unplug that nodes and see if it solve the problem.

Regards.

serge
11-06-2006, 11:00 AM
What happens if you turn on 'Double Sided' for the skin surface?

jasonwestmas
11-06-2006, 11:15 AM
Double Sided is in fact being used to utilize the Kappa Nodes. In the second set of picts all of the nodes have been turned off but the problem still resides. If you just do a simple geometry example using raytraced shadows with a shadow map light I'm sure you would get the same problem I would think.

jasonwestmas
11-06-2006, 11:33 AM
I thought at one point that the geometry for the hair isn't working well with the shadow map. But then I realized that the geometry is in fact being excluded from the shadow map light. Unless shadows don't apply to the exclusion for some reason??