Skip to main content

Track a custom group of players

How to maintain a synced roster of players for something narrower than "everyone in the instance", using PlayerTracker directly instead of AutoPlayerTracker.

When to use which​

Use AutoPlayerTracker when the roster is every player in the instance: it needs no add or remove calls of your own. Use a plain PlayerTracker when the roster is a subset you decide, such as players in an area, in a queue or on a team, since AutoPlayerTracker always tracks everyone.

Steps​

  1. Declare a [WirePool] field. PlayerTracker ships as one of the Core default pool entries, so there's nothing to register on the Configure window first:

    public class SpectatorRoster : TsBehaviour
    {
        [WirePool][SerializeField] private PlayerTracker _spectators;

        protected override void TsStart()
        {
            _spectators.TsSubscribe(this, PlayerTracker.OnTrackingPlayersAddedEvent, nameof(_OnRosterChanged));
            _spectators.TsSubscribe(this, PlayerTracker.OnTrackingPlayersRemovedEvent, nameof(_OnRosterChanged));
            _spectators.StartPlayerTracking(new string[0]);
        }

        public void _OnRosterChanged() => LogInfo(_spectators.LastPlayerIds.Length + " spectators.");
    }

  2. Add or remove players as your own logic decides, for example when a player enters or leaves a trigger volume:

    public override void OnPlayerTriggerEnter(VRCPlayerApi player)
    {
        _spectators.AddTrackedPlayers(new[] { TsPlayer.GetPlayerID(player) });
    }

    public override void OnPlayerTriggerExit(VRCPlayerApi player)
    {
        _spectators.RemoveTrackedPlayers(new[] { TsPlayer.GetPlayerID(player) });
    }

    A player who leaves the instance or gets suspended is removed automatically; you never need to handle that yourself.

  3. Read the roster from LastPlayerIds inside any OnTracking* callback. The owner manages the set: AddTrackedPlayers and RemoveTrackedPlayers called by another player go to the owner over the network.

Why this shape​

See the PlayerTracker reference page for the events, when a Notify* broadcast fires compared to when LastPlayerIds updates, and the three cases that remove a player automatically: leaving, being suspended, or a new owner taking over the tracker.