motion-pipeline

# Motion Pipeline Skill CPU-only motion data processing pipeline for game animation, inspired by Meta's ai4animationpy framework (CC BY-NC 4.0). All operations run on numpy and scipy with no GPU or PyTorch required. ## Why standalone implementations? ai4animationpy's `Math/Tensor.py` imports `torch` unconditionally at the top level, which propagates through every module (Animation, Import, IK, Math). This means zero ai4animationpy modules are importable without PyTorch installed. The standalone implementations in `scripts/motion-pipeline.py` replicate the key algorithms from their source code using only numpy + scipy. ## Environment setup ```bash # Create venv (one-time) python3 -m venv /home/feedgen/vexjoy-agent/motion-pipeline-env/ # Install CPU-only deps motion-pipeline-env/bin/pip install numpy scipy pygltflib Pillow # Verify motion-pipeline-env/bin/python -c "import numpy; import scipy; import pygltflib; print('OK')" ``` The venv is gitignored. The skill documents setup; it does not commit the venv. ## Commands All commands output JSON to stdout. Errors go to stderr with exit code 1. ### import-bvh Parse a BVH mocap file and print a motion summary. ```bash motion-pipeline-env/bin/python scripts/motion-pipeline.py import-bvh FILE \ [--scale 0.01] # scale cm->m for CMU/Mixamo files ``` Output fields: `name`, `num_frames`, `num_joints`, `framerate`, `total_time_seconds`, `bones[]`, `root_trajectory` (x/y/z range). ### extract-contacts Detect ground conta...