function generatePointsCircle(count, clusterCenter, resolution) {
  const circumference =
    circleDistanceMultiplier * circleFootSeparation * (2 + count);
  let legLength = circumference / (Math.PI * 2); //radius from circumference
  const angleStep = (Math.PI * 2) / count;
  const res = [];
  let angle;

  legLength = Math.max(legLength, 35) * resolution; // Minimum distance to get outside the cluster icon.

  for (let i = 0; i < count; ++i) {
    // Clockwise, like spiral.
    angle = circleStartAngle + i * angleStep;
    res.push([
      clusterCenter[0] + legLength * Math.cos(angle),
      clusterCenter[1] + legLength * Math.sin(angle),
    ]);
  }

  return res;
}
From
https://github.com/Leaflet/Leaflet.markercluster/blob/31360f2/src/MarkerCluster.Spiderfier.js#L55-L72
Arranges points in a circle around the cluster center, with a line pointing from the center to
each point.
@param {number} count Number of cluster members.
@param {Array<number>} clusterCenter Center coordinate of the cluster.
@param {number} resolution Current view resolution.
@return {Array<Array<number>>} An array of coordinates representing the cluster members.