Rigidbody Addforce or Velocity no longer working? about mixed-reality-extension-sdk

[norybiak]

An actor needs to have an owner when using rigidBodies, otherwise the client side portion of the SDK will not add the actor to the physics bridge, or perform any action such as addForce().

I discovered that when actors are created immediately after the onStarted() event, the SDK fails to properly update each actor's owner once the authoritative user joins. The _rigidBodyDefaultOwner is still undefined at this point.

Actors with rigidBodies for physics simulation require a different method of instantiation than how the sample apps are doing it (e.g. creating actors after onStarted()). This isn't known since there is a lack of documentation on the matter.

The below is an example of a pattern that can be used to assist with getting around the issue mentioned above.

private actorsWithPhysicsCreated = false;

constructor(private context: MRE.Context) 
{
    this.context.onStarted(() => this.createStaticActors());
    this.context.onUserJoined((user) => {

        if (!actorsWithPhysicsCreated) 
            this.initActorsWithPhysics();

        this.userJoined(user);

    });
}

private createStaticActors() {

}

private initActorsWithPhysics() {

    this.actorsWithPhysicsCreated = true;
}

private userJoined(use: MRE.User) {
    
}

For the SDK devs: A better pattern would be for the onStarted() event to fire once the authoritative user is known and the _rigidBodyDefaultOwner property has been defined.

If an actor is intended to be exclusive, it's best to set the the owner manually.

MRE.Actor.Create(this.app.context, {
	actor: {
		exclusiveToUser: user.id,
		owner: user.id,
	}
});

Edit:

"I discovered that when actors are created immediately after the onStarted() event, the SDK fails to properly update each actor's owner once the authoritative user joins. The _rigidBodyDefaultOwner is still undefined at this point."

I found a fix that ensures actors created without owners properly receive the default owner when created within this.context.onStarted(() => .... See the referenced PRs.