motion-authoring
Motion authoring — from measured manifest to real motion
Runs only when the user chose a converted project and authored motion.
The generator gives you structure, inert skeleton mounts, and
motion.manifest.json (measured triggers, pageTriggers, initial-hidden
hints). Authoring is the step where those mounts become real motion and
the build is proven against the reference. This is the N2 dogfood recipe
(nesil: one 31.21 s master scrub, exact 25,650 px parity).
0. Read the reference, not just the census
The census tells you what moves and roughly when; its selectors are
structural paths, not your ids/classes. Read the site's own motion script
when available and treat the census as corroboration: real trigger count,
pins, scrub ratio, duration, easing vocabulary, stagger delays, which
animations are CSS keyframes vs GSAP vs native scroll timelines.
Use anims[] to verify coverage — never to derive timelines.