method
Ease.back
Ease.back(t) -> fixed
Returns an ease-in that first dips slightly below 0 before shooting forward — the anticipation windup that gives a motion snap. Because it undershoots, the eased value can go negative near the start, so use it where a little overshoot reads as lively rather than wrong.
Example
program Demo {
handler Step phase Update {
let s = Math.lerp(rest, poke, Ease.back(progress))
}
}