3D follow path

[nixiejames]

Maybe have the option to move parts of the motion path in Z space. In Toon Boom, you can do this using the 3D path peg. Basically, you are shown a very simplified top view of the scene and you can easily move the points where the path should be in front of or at the back of something. Imagine the space girl orbiting a meteoroid. Usually, I would duplicate some layers, separate foreground and background, or use patches or masks. That is considerably longer than just modifying the path.

[Víctor Paredes]

You can rotate the path in Z and then sort the layers by depth
Check this file

[nixiejames]

You can rotate the path in Z and then sort the layers by depth

Not sure how I feel about animating the layer order. I was used to arranging shapes from top to bottom without changing layer ordering. Maybe I just need to get used to it. However the effect I was thinking of when I made this request may be too abstract for this method. So instead of a relatively short or small layer like a ball, a long abstract looking element like electricity or magic is spiraling through another element. Imagine wrapping a string along a stick. In that case, one layer has parts that are both in front of and at the back of something. Can it be done without breaking apart that layer?

[Maestral]

"...wrapping a string along a stick".

If I got it right, perhaps masking the string could do the trick?
"Wrap" the string, add effects and whatever you've had planned and then, mask the portions (in form and shape of sections of the stick) where effect is meant to go behind the stick.
I imagine the effect you have in mind could be some sort of combination of stroke exposure, curve profile, newly added brush effects or even liquid shapes. With these masks, you'd preserve the flow of the effect making it still convincing. The problem would occur in portions where the string overlaps itself.

If you'd go for liquid shapes, perhaps there's a possible arrangement to have all these elements combined on a single layer?

Plan B could be the script for sorting layers by Y position : viewtopic.php?f=12&t=33324