Tunnel with Object CHOP

Hi all
I made an instancing based tunnel thingy with the object CHOP that might be useful for vjing and fulldome and stuff. it’s included below. I would love to figure out how to rotate each instance cumulatively if possible to make them twist around the path if anyone has ideas.

enjoy
roller coast.1.toe (7.19 KB)

Do you want them all to spin together or at different rates?

You can spin all of them together by changing the value of geo1’s ry parameter. This will make all of them spin together.

I’ve been trying to get each one to have an offset rotation so they cumulatively rotate along the path. like, where each one is rotated 15 degrees more than the one behind them. But i’m already using the rotate part of my instancing to make the gate things always face the right way. any pointers?

There are a few things I’d do differently here. Instances are perfect if you have animated geometry, but if you’re working with something that’s static it’s safe to use sops instead - as there are a few tricks that are pretty neat there.

Rather than instancing, I’m using a sweep SOP to place copies of your torus along the path of your circle. You’ll notice the sweep SOP has a twist parameter allowing you to introduce rotation for every copy.

I also simplified the camera rig - using a SOP as a path is one of my favorite camera tricks, and here I’ve just parented your light and camera to a null, and set the null to follow the path of your cam_track SOP.

This is the most straightforward solve, if you’re after animated instances though you’ll have to do all the rotation math in CHOPs.

Hope this helps.
roller coast_sweep.toe (7.15 KB)

Thanks so much Matthew! I’m still trying to make this work with instancing for efficiency reasons but maybe a sop that goes out a little in front of the camera along the path is the solution. gonna keep trying.