Clustering in Mapbox Unity

mapbox-clustering

private static float MIN_PIN_DISTANCE = 8;

/* Prefab should include a TMP_Text component in its hierarchy
   to be used for exposing number of clustered items to user */
[SerializeField] private GameObject clusterPinPrefab;

private Dictionary<GameObject, (int id, Vector2d coords)> _spawnedPins 
    = new Dictionary<GameObject, Vector2d>();
private Dictionary<GameObject, Vector2d> _spawnedClusterPins
    = new Dictionary<GameObject, Vector2d>();

/* Call this function when user finishes the pinch-to-zoom gesture */
private void SpawnClusters()
{
    foreach (var cluster in _spawnedClusterPins)
        Destroy(cluster.Key);
    _spawnedClusterPins.Clear();

    foreach (var pin in _spawnedPins)
        pin.Key.SetActive(true);

    var pins = _spawnedPins.Keys.ToList();

    for (int i = 0; i < pins.Count; i++)
    {
        var markerList = new List<GameObject>();

        for (int j = i + 1; j < pins.Count; j++)
        {
            if (pins[j].activeInHierarchy == false) continue;
            var distance = Vector3.Distance(
                pins[i].transform.position,
                pins[j].transform.position);
            if (distance < MIN_PIN_DISTANCE)
            {
                markerList.Add(pins[i]);
                markerList.Add(pins[j]);
                pins[i].SetActive(false);
                pins[j].SetActive(false);
                j = i + 1;
            }
        }

        if (markerList.Count > 0)
        {
            var cluster = Instantiate(clusterPinPrefab);
            cluster.transform.position = pins[i].transform.position;
            cluster.GetComponentInChildren<TMPro.TMP_Text>().text = (markerList.Count / 2f + 1).ToString();
            _spawnedClusterPins.Add(cluster, _spawnedPins[pins[i]].coords);
        }
    }
}