sundays
Character Tracking — Performer Motion Reconstruction
In addition to camera and environment tracking, the movement of the on-set performer in a green suit was tracked as a separate 3D object. Markers placed on the suit allowed us to reconstruct the actor’s full-body motion, which was later used as the base animation layer for the CG robot.
Unlike traditional workflows involving 3DEqualizer or external motion-capture software, we completed all character tracking directly inside Nuke using KeenTools GeoTracker. This approach drastically simplified the pipeline — letting us track, validate, and preview the 3D motion directly on the plate without round-tripping to other applications.
Workflow
- Model Preparation — a simplified humanoid proxy mesh was aligned to the performer’s proportions inside Nuke’s 3D space.
- GeoTracker Initialization — key frames were manually adjusted for torso, head, and limb alignment.
- Automatic Tracking Pass — GeoTracker analyzed the performer’s surface motion frame by frame, generating stable 3D transformations for each body section.
- Export for Animation — the tracked motion curves were exported as FBX and transferred to Maya, where they served as the base for robot animation and timing.
- Validation — the tracked geometry was re-projected onto the plate to verify accuracy before retargeting.
Tracking the actor directly in Nuke using KeenTools GeoTracker allowed us to stay inside the compositing pipeline — saving time, eliminating data transfer errors, and keeping the tracking perfectly aligned to the final comp camera.
