PDA

View Full Version : ambient occlusion from gound only...

ragdoll
10-30-2009, 04:32 PM
i'm trying to get just the soft shadows off the ground from my AO pass, similar to how you'd get just a standard shadow pass by using the "usebackground" shader, but it seems that just by applying a standard "usebackground" shader on the ground, the soft shadows don't show up...well, shadows show up but it's not the same as the shadows i'd get if i didn't use anyother shader aside from the AO.

i just need to change the background color in after effects, and the AO shadows add a nice soft touch to it. So is there anyway to mask out just the ground shadows from an AO pass? Thanks in advance!

-rj
israelyang
10-30-2009, 10:51 PM
if you want AO on the ground from the object but without the object visable, just turn the object's primary visibility off.
phix314
10-30-2009, 11:12 PM
The Use Background shader has always been a pain in the ass, least for me. With the latest installment of Maya 2k9 (maybe 2k8...?) there's some "hidden" shaders. There's a mip_background or somesuch thing that works well for integrating shadows and the like. May want to take a look at those.

http://forums.cgsociety.org/showthread.php?t=541718

If those are unavailable to you, I would go the whole "primary vis" route and a seperate pass with a normal shader.
CGTalk Moderation
10-30-2009, 11:12 PM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.