Taro Rig (WIP)

A stylized cat rig made as a part of my capstone project for Texas A&M’s Undergraduate Visualization Program. Taro is a flexible little cat with a great degree of control for hitting exaggerated poses in animation. He was created with a custom scripted rigging library for Autodesk Maya

Thanks to my fantastic mentors:

Qiao Wang

Amber Ackley

Caleb Kicklighter

The Project

For my capstone project, I am creating a 3D character rig that can emulate mor of the fluidity of form achievable in 2D animation. The character I am creating is a black cat. Cats in general have a reputation of behaving “like a liquid.” Black cats specifically enhance this effect due to the lack of defining features on their fur to signify depth or surface curvature.

Inspirations

In analyzing the existing cases of stylized rigging and animation, I found a good subject matter for emphasizing the elements I was interested in: cats. House cats have a long history of representation in animation, and even in reality have a reputation of being flexible and exaggerated in their movements. Black cats in particular can be rendered in a way that turn them into an almost literal “silhouette,” which complements my interests in flat shading and shape abstraction.

Most of my inspiration came from 2D illustrations of black cats

Planning

Initial Sketches from Late 2022

In the planning stage, I mainly made sketches. It was here that I worked out many of the features that I wanted to include, and outlined early potential hangups and solutions. I drew out what types of poses my eventual character would need to be able to hit, and described the sorts of model considerations that would allow those motions to be achievable.

Production

The production broadly consisted of two stages: research and development followed by polish. I spent the first half of the semester testing the different elements I would need to make the rig components work, then I put them all together around the midpoint of the semester. Then, once I was able to see it all together, I began addressing issues and polishing the rig as a whole.

Limbs
Ribbon-Based Limbs

I decided early on to make sure the limbs were based on ribbons. These are really important for allowing each limb to move and deform in a smooth way. They also have the benefit of providing scale control along the entire limb.

Limb Sliding

Each limb will slide along the surface of the torso regardless of deformations. I had figured out a manner of blending separate meshes with the Shrinkwrap deformer, but this was the step that really made that effect controllable for artists.

Limb-torso Transition

Each limb also has a set of mechanics designed for controlling the amount of transition there is between limb and torso. This is set up with a combination of blend shapes, joint weighting, and attributes in the shrinkwrap deformer.

Torso

For the torso, I went through several different approaches before settling on a lattice system driven by a ribbon. This allows the torso to flex in the manner of a traditional rig while still allowing the animator to manipulate the lattice points for more extreme shapes and silhouettes.

Head

The was composed of three different elements: the head itself, a pair of eyes, and a pair of ears. The head is functionally identical to the tail, but serves as the core to a set of flexible eye controls, and a pair of ears that can both slide anywhere on the head.