pub fn spring_step(
progress: f32,
velocity: f32,
target: f32,
dt: f32,
stiffness: f32,
damping: f32,
) -> (f32, f32, bool)Expand description
One damped-spring step (semi-implicit Euler) driving progress towards
target, primed by velocity. stiffness/damping set the stiffness and the
damping (≈ 2·√stiffness = critical damping, no overshoot).
Returns (progress, velocity, at_rest).
A general-purpose motion helper: used by screen transitions and by gestures (a settle primed by the finger’s velocity).