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View Full Version : Why do Dmap Shadows hate me so?

Pixelcritter
03-03-2009, 12:26 PM
Up until recently I've been sticking to raytrace for the simple fact that me and Dmap shadows do not get along. My problem is that in this particular scene I have this alien character decending from his ship in a lightbeam. Now I've been trying to get this light beam (a spotlight) to cast shadows under the character in the air. I've gone through the few popular tutorials by A alvarex and what not but I can't seem to get these dmap shadows to work. Can anyone spot somethin I'm missing, I sure can't. :curious:

http://img291.imageshack.us/img291/1223/shadowssssss.jpg
InfernalDarkness
03-03-2009, 09:38 PM
...then the participating volume approach might work better, and you could revert back to raytraced shadows?
bwheels02
03-05-2009, 06:11 AM
What do your render settings look like?
Elvis75k
03-05-2009, 11:15 AM
Arise the Dmap bias, also the resolution of the dmap looks a bit to high if you render at 640*480. Use the ipr to tweak params, is more easy. Maybe the cone angle is also to high.. try to focus the stuff you want to cast shadow inside the cone, or use raytrace insstead.
Volumes and raytrace gives good results with mr..
one
03-05-2009, 11:37 AM
What do u mean by it doesn't work? I think you need to be more specific before anyone can give you a good answer or to help. :) A screen shot would help..Let us know..!
one
03-05-2009, 11:39 AM
also, what is the size of your scene? I don't mean memory wise, i mean size when compared to the Maya grid.
Pixelcritter
03-05-2009, 04:24 PM
Okay, I have reverted back to Raytrace to see if this goes any smoother.

The left is what it looks like atm with Raytrace shadows. The right is what I'm trying to achieve.
http://img120.imageshack.us/img120/382/light1.jpg

In terms of render settings this is what I have.http://img99.imageshack.us/img99/3125/render1.jpg
InfernalDarkness
03-05-2009, 06:57 PM
...raytrace shadows won't accomplish what you need. You'll need to use the parti_volume shader and also (if you intend for caustics/GI) the parti_volume_photon shader as well.

In your Render Settings, Raytracing likely needs to be your primary renderer, not scanline.

Shadows need to be "Segments", not "Simple."

Is this Maya 2008? If you have trouble understanding the parti_volume shader, just do a search on it in this forum.