#Shadows dancing
8 messages in this thread
I am rendering an animation and I am getting this weird flickering of
the shadows. Does it matter what type of surface or map a shadow is
cast upon? I have not seen my shadow do this before on any other
animation. Any help, thanks.
Hi James,
<< flickering faces.. >>
I found the following two posts on the subject..
Sounds like either too-low resolution on the shadow map or possibly the state
of the ABSOLUTE-SHADOW-BIAS 3DS.SET command. (you might want to try it both
ways, AND increase your shadow map res… what smap res are you currently
using?)
– G
If you've got hide keys for objects that are not visible, but still in the
scene, that could easily explain it (since the shadows are computed based on
all the objects in the scene). Here's something you can try… add a line to
your 3DS.SET file (if it's not already there) that says:
SHADOW-BIAS-ABSOLUTE = YES
When this is set to YES, the bias values for shadows won't be
recomputed on every frame, so hiding an object in the middle of an
animation won't change the shadow bias. (No is the default)
– G
James,
I have had that same flickering shadows problem with large files.
I tried all sorts of things but I never have found a solution. I do, however,
know of a down and dirty workaround which might work:
Delete as many objects and lights from the scene as possible — things which
you don't need in the particular frames which show the flicker. Then re-render
just those frames in which the flicker showed.
Good luck.
Alec Jason
Alec, trying turning SHADOW-BIAS-ABSOLUTE on (in your 3DS.SET file). That ought
to eliminate your shadow flickering problems.
– G
Thanks much, Gary but I _think_ I already tried that SHADOW-BIAS-ABSOLUTE on
thing and as I remember, it made no difference. I'll try it again.
Thanks again,
Alec Jason
It doesn't sound like you're sure. Give it a shot and let me know exactly what
happens.
Thanks,
– G
The other thing I have found with flickering shadows is the spotlight
in question having a massive falloff, or the object the shadow is
cast onto being a very large bax with only two faces stretched across
the whole scene. – Peter
Right. It always helps to have some geometric complexity in those large
planes.
– G