Tips for rigging a Maya Tentacle/LongNeck creature


#1

Hi people of CG society,

This is my first post here, so bear with me.

I am currently developing a rig for a VFX studio, I can’t give too much away but I will describe what I need from the rig.

Probably the best way to reference the kind of creature I’m rigging - in terms of function, would be a snake on Medusa’s head. So there is a base that the rig must follow, and a head that needs its own autonomy - separate from its body.

If I describe what I want it to do, then what I’ve already tried, perhaps there’ll be some suggestions based on that.

Requirements:

  • The body can be manipulated without affecting the head.
  • The volume of the body remains, no stretch.
  • The neck/body can twist and turn, the head needs to be able to reach behind itself, down to it’s base etc.
  • There needs to be tweak controls, for editing the overall shape.
  • There needs to be non-linear deformers, for adding sine etc.
  • It needs to be able to twist around itself, imagine multiple of it, they need to writhe around each other.

What I’ve tried, dabbled with:

  • Ribbon setups, using a wire deformer to move it around, then controls driven by follicles to move joints etc.
  • Ribbon setup with a kind of FK setup for structure.
  • Spline, with fk system over the top.
  • Spline with an ik system over the top, which drives the position of the tweaker controls, which can be moved around separately.

The ribbons are too stretchy, it’s hard for anim to maintain the volume - it’s guess work whether it’s stretching or not.

The splines Twist flips and is very fiddly and unforgiving.

I would appreciate any links to tuts, blogs, books or anything that can explain the best practice.

Thanks in advance, I look forward to your wisdom!!


#2

Hey,

So, no bites so far. That’s okay, I have put something together that is currently delivering very good results - pending more extensive testing.

If there are riggers out there that may be interested in the setup we can discuss it here. I may be able to put a video together soon if the interest is there.


#3

Looks like your trying a lot of stuff! - For twist i’d looking into keeping the tangency consistent by creating parallel transport: https://en.wikipedia.org/wiki/Parallel_transport - basically you want a baseline coordinate system your twist works against. You create something called a Rotation Minimizing Frame - https://www.microsoft.com/en-us/research/wp-content/uploads/2016/12/Computation-of-rotation-minimizing-frames.pdf.

For the ribbons being too stretchy - maybe look into motion paths. Theres some pretty cool stuff you can do with their parameterization properties.

-c


#4

Thanks for the reply, the concepts you reference sound very promising. Do you have any examples, or videos where it is implemented - rather than a theoretical point of view?

TBH