#Flicking Faces
8 messages in this thread
On occasion, I have run across a model that creates flickering faces. I wish I
could be more specific, but that is exactly what they are. I single face on a
surface will flip from lighter than the surrounding area to darker on a 2 to 4
frame interval. This creates a very distracting flicker when I play back a
finished animation.
I have noticed this phenomenon in both R2 and R3. In my recent experience, I
decided to find out what the problem was (using R3). Changing the shading
mode, textures, blurring, and filtering method produce no solution.
The object in question is an L-shape created from the 2D shaper, then lofted
(it is used as a brick wall). When rendered, a single triangular face flickers
intensly for no reason.
By removing all smothing groups from the object, the problem vanished.
If I auto-smooth it again, the problem comes back. I have noticed
this with some boolean models too, but only recently found a
work-around with the extruded L-shape.
This is not a pressing problem since I have found a work-around.
However, I was wondering if anyone knew of what conditions might
predictably cause this phenomenon so that I may avoid it in the
future. Any thoughts are appreciated. — James —
I had a similar problem on one mesh in R2. It seems as though face
was flipping its normals over 1 or 2 frames for no apparent reason.
Must be a memory conflict <g,d,&r>. Didn't notice it until I put it
on an Abekas and played it back at $200/hr. Oh, well… I haven't
run into the problem again, though (he said with crossed fingers as
he knocked on wood).
Regards,
John Tissavary (La Luna cie)
This seems to happen most often after boolean operations, James, and
can always (at least in my experience) be fixed with smoothing
operations.
This can also happen when you have coincident faces, ie 2 faces that are right
on top of each other and coplanar. Make sure you don't have such a case.
Yann Bertaud – VPG, Autodesk.
*What* can happen, Yann? To tell ya the truth, I've forgotten exactly what this
thread was about, or my previous comment in it (if there was one). Must have
had a little too much holiday cheer yesterday<g>…
Have a nice holiday,
-Alan
PS — I feel pretty good this morning, no hangover at all!
That explains my problem a couple of months ago. I fixed it, but it's nice to
know why the face was "flicking".
thanks,
John Tissavary (La Luna cie)
James,
Could you zip and email your reproduceable example so we can look at it?
(Please include a brief Readme.doc to jog my failing memory.) Thanks.
– Jack
Thanks for the input everybody.
Jack, the file is rather large, but if I can wittle it down to just the one
object, I'll zap it over to you.
Got it wittled. See file Flicker.Zip in your mail! Thnaks! — James —