Goes on: Position
Real gravity: the layer falls from above at its in point and bounces until it rests on its position.

// Bounce Drop — Coherent Motion Expressions · getcoherent.app/resources
var height = 600;   // pixels above its position
var gravity = 2800; // pixels per second squared
var elastic = 0.5;  // 0 = thud, 0.8 = superball
var t = Math.max(0, time - inPoint), t0 = Math.sqrt(2 * height / gravity), y = 0;
if (t < t0) { y = -height + 0.5 * gravity * t * t; }
else {
  var v = gravity * t0 * elastic, tt = t - t0;
  while (v > 40 && tt > 2 * v / gravity) { tt -= 2 * v / gravity; v *= elastic; }
  y = v > 40 ? -(v * tt - 0.5 * gravity * tt * tt) : 0;
}
var out = [value[0], value[1] + y];
if (value.length > 2) out.push(value[2]);
out
