Networked GameObjects can be owned by a connection.

Objects that are owned by a connection are simulated by that connection. Their position and their variables are all controlled by the controlling client.

If an object is unowned by a connection then it is simulated by the host.

Owner Transfer

By default, a networked object's owner can only be changed by the host. However, the current owner of the object can change that behavior by setting its OwnerTransfer value.

// Make it so anyone can change the owner of this networked object.
go.Network.SetOwnerTransfer( OwnerTransfer.Takeover );

Getting the Owner

You can find the owner of a GameObject by checking Network.OwnerId.

public override void Update()
{
	Log.Info( $"Owner is {Network.OwnerId}" );
}

In reality, day to day, you won't really be interested in the particular owner. You only care about whether you're meant to be simulating it or not. You do that by checking IsProxy - which is true if the GameObject is being simulated by another client (or the server).

public override void Update()
{
    // this is controlled by someone else
    if ( IsProxy ) return;
    
    // if we pressed E, try to pick something up
    if ( Input.Pressed( "use" ) )
    {
        TryPickup();
    }
}

Taking Ownership

You can take ownership of an object, which makes you the simulator.

void TryPickup()
{
	// are we looking at anything?
	var tr = Physics.Trace.WithoutTags( "player" )
			.Sphere( 16, EyePos, EyePos + LookDir.Forward * 100 )
			.Run();

	if ( !tr.Hit ) return;

	if ( tr.Body.GameObject is not GameObject go )
		return;

	if ( !go.Tags.Has( "pickup" ) )
		return;

    // You're my wife now
	go.Network.TakeOwnership();
 
    // Store that we're carrying it 
	Carrying = go;
}

So for example, if a player picks up an object, the player could take ownership of that object. That way the position is controlled by that player.

If a player gets in a car, you could make the player the owner of that car - then its position will be controlled by that player.

And of course, the player is generally controlled by its own connection.

Dropping Ownership

You can also stop owning an object. At that point the object becomes owned by the server.

void ThrowObject()
{
	if ( !Carrying.IsValid() )
		return;

	// Stop owning this
	Carrying.Network.DropOwnership();
	Carrying = null;
}

Default Owners

If you make an object in the scene editor networked, by default it will not have an owner. It will be simulated by the host.

When a client creates a network object via GameObject.NetworkSpawn(), they will be the owner of that object.

Disconnection

By default all networked objects that a client owns will be destroyed for everyone when they disconnect. You can change this by setting the Orphaned Mode for that networked object. Only the current owner can change the Orphaned Mode.

Simply call GameObject.Network.SetOrphanedMode with one of the following options: