Follow-through

Full motion specification

How the movement works

Use it on hair, clothes, accessories or the trim of a logo, so that the parts attached to the main body feel weighted.

1. 01One move per 2.35 s (twice per 4.7 s, alternating direction). The body is a mint circle (radius 38). It travels 303 px at 0.15–0.85 s: it speeds up over the first 30%, then keeps a constant speed and stops abruptly at 0.85 s.
2. 02Flag (58 px white pole with a yellow flag): its angle is a spring pushed by the body's acceleration, a″ = −121a − 5.5a′ − 0.0175 × acceleration (natural frequency 11 rad/s). The cloth bends a further 0.6 × the pole angle.
3. 03Tail: seven 14 px segments (coral, width 14→6) on a slower spring, b″ = −56b − 2.8b′ − 0.012 × acceleration. Segment j uses the value from j × 22/600 s (about 0.037 s) earlier, scaled by (0.55 + 0.16j).
4. 04Both springs are precomputed in 1/600 s steps; drawing only looks values up.
5. 05In the last 0.3 s of each move the swing is faded to 0 with smoothstep, so the loop has no seam.