constructor({
        fps = 60,
        timestep = 1 / fps,
        broadphase = BroadPhaseType.BVH,
        gravity = new Vec3(0, -9.81, 0),
        velocityIterations = 8,
        positionIterations = 8
    } = {}) {
        this.timestep = timestep;

        this.world = new World(broadphase, gravity);
        this.world.setNumVelocityIterations(velocityIterations);
        this.world.setNumPositionIterations(positionIterations);

        this.objects = [];
        this.map = new WeakMap();

        this.v = new Vector3();
        this.q = new Quaternion();
        this.object = new Group();
        this.matrix = new Matrix4();
    }
A class for using the OimoPhysics 3D physics engine.