Road to Echo: Rigging Neo

Work In Progress / 12 October 2020

Neo had a similar base set up to Echo with IK/FK switch arms, IK legs, and a face rig. He did have additional clothes on him, however, that required some extra joints and the ability to take off the bandana on his head altogether. I laid out all of my intended features for version 1.0 down as follows:

  • Face Rig / Blendshape correctives
  • Ear Control
  • IK/FK Switch
  • Foot Roll
  • Shirt Adjustment Joints
  • Head/Neck Space Switching
  • Eye Space Switching
  • Hand Set Driven Keys/Adjuster Controls
  • Nose Nuzzle Option
  • Bandana Visibility Toggle
  • Stretchy Spine


I started working first on the spine before tackling the rest, taking care to make a separate spine chain that I would be messing around with and parenting each joint to the actual spine chain. This was something I saw first with Echo, as doing this directly on joints that would be going into Unreal would create a transform node due to my scaling to get the spine stretch. 

Stretching it out super out there really helped me get my skinning and edge loops weighted correctly, though it was a much longer process than I first thought as Neo had a shirt that also had to stretch. That is still being worked on.


The legs had a smilier issue as Echo's legs because of how hamsters/gerbils have more fat collected towards their legs, making placement of te knee joint to be a tad more challenging. Neo does not have a lot of scenes in where his legs/knees are shown, however, therefore for animation and the intended shots in the film as it stands,  it will not be as much of an issue. Regardless, there is a basic setup in the legs should that plan change for now.


I wanted to have the option of a little more control for the shirt when it deforms and moves around the body, therefore I included some shirt joints in the rig that were parent constrained to controllers. The same goes for the bandana in case Neo were to move his hand up and adjust it or if I wanted to move the clothing to achieve a specific pose. Similar to Echo's hair, the actual bandana ends are simple IK handles that can move quickly and easily. These additions could also be used by Unreal for the physics asset and have it be procedural, though there is still some testing to be done to see which approach is better for the purposes of the film.


Neo's Eyes are much bigger than Echo and most of the other characters in the entire film. Because of that, I wanted to have pupil scaling play a more significant role in Neo's rig than it does in Echos. Instead of doing UV adjustments of moving the actual UV map around the eye when moving the controller, I elected to do joint based pupil dilation to give the impression that the iris was also shrinking and growing as the pupil dilated. The final result looks like this:


Hamsters and gerbils have very large "pouches" in their cheeks to help them store lots of food, therefore to get correct movement for anamorphic facial expressions, I had to pay very close attention to what the cheeks would look like in 3D space. I consulted a lot of different 2D designs, namely character like Hamtaro and Chip and Dale, to see how the forms of the cheeks play out in 2D. The first pass at different expressions is not a final polished one, but I believe it is a step in the right direction. Doing this did help me notice some texture issues, however, as the ambient occlusion map baked into the overall skin texture and is most noticeable when I move the eyebrows away from their starting position.


Neo's rig built on the knowledge I learned from Echo and also carried it's own unique challenges. Working on Neo's face for blend shapes will be more challenging and time consuming, but I'm confident that it will lead to much more expressive emotions and acting once we get into animation. I worked on this rig in a more spaced our process than I did with Echo due to other factors of my life taking more time away from this project, but I do think that ultimately helped the process overall as I had more time to think about why certain issues were occurring and how to go about solving them. What is a good thing to always point out, though, is that rigs are often never really finished until the project itself is done. It takes rigorous testing with animators' help to identify problem and deformation issues, and thus the rigger would adjust and iterate to help. Rigs are living files, and I see that as being especially true for our little friend Neo.