Overview
As a personal project during the 2023 fall semester, I reconstructed the UVN facial rig used in Blue Sky Studios’ Peanuts Movie. The final version of the rig is made with the Bifrost node system, which I studied online during the latter half of the semester.
UV Position Sampling
Instead of working with a traditional face rig, UVN rigging wraps a flattened "face" mesh onto a “skull” object. To best replicate this effect, I queried surface positions from the skull's UV map. The flattened face mesh handles coordinates similarly to the UV map, and can use the sampled positions as a guide for wrapping onto the skull's surface.
The face mesh can be manipulated without affecting the skull’s shape, allowing the character’s head to retain its profile independently of the character’s expression.
If the skull is altered, the face mesh will readjust to its new shape.
Normal Offset
To facilitate depth on the surface of the face mesh, I multiplied the wrapper's vertex Z axis positions by the skull's normals. Inward/outward deviations on the flattened face mesh are automatically extruded from the skull's surface when the face is wrapped.
