Fish Rig
Goals:
Rig a realistic fish character for my thesis film
To keep animation easy, include dynamic- and expression-driven secondary elements, as well as an easy way to animate along a curve
The fish is the lead role in my MFA thesis film: A Fish & A Bird. Unlike some of the other rigs I’d done up to this point, I got to be involved in the modeling of the fish as well. I worked closely with a friend and collaborator, Jill Smith, to build this character to my specifications for the film. I knew I wanted realistically mechanical creature characters, with a stop-motion feel to them; “like you’d taken a dead fish and built a puppet out of it.” I also knew I was handling the water simulation, and therefore the rendering of the project, in Unreal Engine, so the rigs would need to be compatible. The fish would be tasked with singing a bespoke opera, and in tandem garnering sympathy from an audience while also being laughably absurd. No small feat for a rig!
The real technical achievement of this rig was in making the secondary fins and tail "dynamic.” I ended up applying sine functions to the joint chains of the dorsal, anal, and pelvic fins. The tail, also expression driven, got its rotation values from the rotation of the last joint of the fish’s spine, making an elegant swim cycle super quick and easy to animate. I also made sure to expose the amplitude, frequency, and offset values of all of these functions, so that my guest animators and I could adjust as-needed, or even turn the expressions off for specific moments. The controls for these driven fins remained usable on top of the expressions, as well, so the animator can put as much (or as little) time as they want into those details and still arrive at something that fits the world of the film.
To allow for both moving cameras and a stop-motion baked-on-twos-and-threes animation aesthetic, I built both the fish and bird to be able to be animated along a curve. To animate to a moving-camera shot, the animators could set the fish to follow the same curve as the camera, and still have complete control over its position beneath that animation.
Working on rigs for my own long-term project really offered me a glimpse of the interconnectedness of the modeling/rigging and rigging/animation parts of the pipeline. As I started rigging, I would often return to the modeling stage to make updates based on what I needed, and even once I put my “animator” hat on, rigging was never really over. I made a reversed version of the fish to make animation easier on just four shots in the same week that I animated them! I also learned that I love the anatomical research phase of building a rig; becoming a Fish Expert and then translating that into an effective rig-construction was one of my favorite parts of the year of working on this film!
For more information on A Fish & A Bird, head on over to the “Films” page, or click here!