# Complete vector-to-angle helper and alias behavior

RE-661. Reproduce with `python3 scripts/analyze_qvm_vector_angles.py`; check with `python3 scripts/test_qvm_vector_angles.py`. The [machine report](qvm-vector-angles.json) retains source identity and bounded fixtures.

Complete62945–63119 writes negative pitch, yaw and zero roll. Zero horizontal input bypasses all native math and selects pitch90 for positive z, otherwise270; thus the zero vector writes−270, not a normalized zero angle. General input uses yaw atan2(y,x), a rounded horizontal length and pitch atan2(z,length), with single positive-turn corrections before negating pitch. Exact input/output alias works because the source completes input reads before publication. Finite math.atan2/sqrt are supplied native models and do not establish original library bit parity; partial overlaps and nonfinite domains remain open.

No original executable/full QVM/native collision/physics/rendering executes. Native responses and legal input domains are supplied or unverified where stated; full runtime/macOS/Linux Rust/Bevy/Solari gameplay remains open.