OT: Lookat controller flipping problem

[tricky]

I know this is a little off topic, but I have had to resort to using masked people on quad patches in my current animation because of stability issues with RPC and Vray.

Anyway, I want the quadpatches to rotate using a Lookat controller so that they always face the camera. This 'seems' quite straightforward. In fact, with various trial-and-error clicks on the various orientational controls within the Lookat controller, I can get the quadpatches the right way up and facing the camera nicely.

HOWEVER, at certain points along the animation path, the quadpatches suddenly flip over and my people turn upside down! Obviously not good. I remember this issue from My Max 1.2 years, and I never did solve it.

What do I do? Any tips would be great.

Thanks
Tricky

[plastic_]

lock the z axis.
i cant go into details now, but you might want to look at my treeshop script for an example of scripted controllers.
link below.

[tricky]

thanks plastic_, but I don't seem to be able to lock the z-axis. If I go to link info and modify the rotation x,y,z axis, I don't see any difference.

Am I going mad?

[casewolf]

Hi there,

I encountered the same problem and switched to the free billboard script -plugin. I remember you can download it somewhere at scriptspot or 3dmaxer.dk or somewhere - have a look around. I can send it to you as well...

[tricky]

casewolf - I did find that plugin yesterday, and it seemed my problem would be solved. However, it doesn't appear to be compatible with Max6.

Do you have a newer version?

[trixian]

Have you specified the correct up-axis?

[tricky]

yes, and at first, that seems to work. But the camera loops around 360 degrees, and about halfway around its path, the quadpatch that is looking at the camera flips!

This is driving me mad!

[trixian]

hmm..never experienced this with the look-at controller other than when it gimbal locks if I orbit the camera over it.
Most likely you will have more luck on the discreet 3dsmax forum.