I seem to remember something like this. I think the offending object was
a very large (overall dimension - not complexity) sds object with
smoothing applied.
I think I solved it by converting it to triangles.
Chris M
leee wrote:
On Tuesday 04 Aug 2009, Mark wrote:
Hi all,
I get this error when rendering an animation, but only at certain
frames:
Non-convex polygon (Error: r3raster: 401)
Rendering continues, but huge artifacts appear. Only a few frames
out of 600 are affected but it's a pain in the ***!
I found out it's related to box rendering. Using fewer larger
boxes or even switching it off completely seems to help, but I
don't want to do that with a quadcore machine! Any ideas??
It's a very simple scene, camera between large analytical
spheres.
TIA,
Mark H
I dunno, but it sounds like, due to the box rendering, the camera is
partially seeing the inside of something that it's expecting to
only see the outside of. Could it be related to the Near clipping
plane of the camera?
Do the artifacts appear across different render boxes or are they
restricted to just particular boxes.
If I got something like this I'd try playing with slightly different
fields of view, different clipping planes, different depths of
focus and adjusting the camera path slightly. As the objects are
simple analytical spheres I'd probably try re-sizing or re-creating
them too. You could also try using a different number of render
boxes so that the box boundaries are in different places i.e. if
you were using 4x4 boxes, try using 5x5 instead, just in case the
box boundaries are lying exactly across a point; the point would
then need to be in both render boxes but one box might interpret it
differently to the other box.
I've also hit a few strange artifacts when the camera Far clipping
plane has been way beyond the scene I'm trying to render and I
believe this may be due to precision limits - if you're looking at
something a few millimetres away but the far clipping plane is set
to millions of metres the fp hardware can run out of dynamic range
i.e. it doesn't seem to be able to maintain a resolution of, say
0.001mm when it's also got to cope with stuff that's 1000km away.
Just guessing, of course.
LeeE
