nx_dance_emit.nx

nx_dance_emit.nx -- DANCE-MOTION KEYSTONE v2: the being DANCES from REAL third-party mocap (ws=dance-motion 2026-08-10). v2 (operator saw v1 live: "tearing and junky"): the two roots were (1) LOCAL-Euler rotation transfer -- with the mocap's collar/spine frames dropped, absolute limb poses were wrong; (2) rigid one-joint binding -- triangles spanning a joint tore into spikes at real dance angles. v2 replaces both: RETARGET BY POSITION: FK the mocap skeleton per key (world quats+positions from the clip's own channels), take each segment's WORLD direction (shoulder->elbow, elbow->wrist, hip->knee, knee->ankle), de-yaw by the dancer's hip axis (torso-relative dance, stable body), mirror X into our rig's handedness, and drive each bone as the minimal rotation from its rest (-Y) to that direction. Correct poses BY CONSTRUCTION -- no local-frame luck. SMOOTH TWO-BONE SKIN: per-vertex second joint + Q14 weight, blending BOTH sides of every joint pivot over a 150-unit band (child side toward parent, parent side toward child) -- kills the tears. Plus: ONE skin tone (per-part colours read as patches -- the showcase organ measured this first). usage: nx_dance_emit [file.bvh] default knowledge/fixture_mocapbank.bvh; writes nx_dance_emit --kat selftest incl neg-control + exact quat values exit 0 ok | 1 teeth RED | 2 unreadable | 3 usage | 4 REFUSED (parse or joint-map) license_tier: ORIGINAL No hw writes (Rule 26). expect_exit: 0