Hi! I am running Houdini 9 Apprentice HD (build 9.0.794) on a Dell laptop running Windows XP with a NVIDIA Geforce Go 6800 graphics card.

I am working on an old Houdini tutorial that teaches
you how to build a rollercoaster. Unfortunately, when
I view the geometry through one of my cameras, the
geometry flickers. The geometry turns black and then
back to its original color.

I have played with the clipping planes in the cameras
and the lights. I have tried to adjust the normals
with the Facet SOP. I read one frame of the track out
and imported it back in. None of these solutions
worked.

What did work was changing the two distant lights I
used to an area light. I removed the scene file with
the area light to make the zip file smaller.

I have approached colleagues and people on forums
about this problem for several weeks and have tried
their solutions to no avail. I hope you can help me!

Thank you!

Hi,

I'm seeing your problem & the immediate fix is not to use Distant Lights. However, there are no problems rendering with them.

I'm not sure why the GeForce Go (I have a 7600 in my laptop) has display issues with the Distant Light. On my workstation with a Quadro, I don't see this problem.

If you would like to continue using the Distant Lights, I would suggest turning on headlight (two buttons down from the construction plane button) so the viewport doesn't use the Object lights when displaying.

I'll try some stuff & see if they will help.

Cheers!
steven