How to use the proton-engine.Velocity function in proton-engine

var f = this.getArrProp("f");
            var emitterV = this.getProp("emitter");

            this.proton = new Proton();
            var emitter = void 0;
            if (emitterV === "follow") {
                emitter = new Proton.FollowEmitter();
            } else {
                emitter = new Proton.Emitter();
            }
            emitter.rate = new Proton.Rate(num, rps);

            emitter.addInitialize(new Proton.Mass(mass));
            emitter.addInitialize(new Proton.Radius(radius));
            emitter.addInitialize(new Proton.Life(life));
            emitter.addInitialize(new Proton.Velocity(v, tha, "polar"));
            if (body) emitter.addInitialize(new Proton.Body(body));

            var pos = void 0;
            if (position === "all" || position === "screen") {
                pos = new Proton.Position(new Proton.RectZone(0, 0, canvas.width, canvas.height));
            } else if ((typeof position === "undefined" ? "undefined" : _typeof(position)) === "object") {
                pos = new Proton.Position(new Proton.RectZone(position.x, position.y, position.width, position.height));
            } else {
                emitter.p.x = canvas.width / 2;
                emitter.p.y = canvas.height / 2;
            }

            emitter.addInitialize(pos);

            /// behaviour
            var alphaB = alpha ? new Proton.Alpha(alpha[0], alpha[1]) : new Proton.Alpha(0, 1);

once = _ref$once === undefined ? "all" : _ref$once,
          _ref$alpha = _ref.alpha,
          alpha = _ref$alpha === undefined ? 0.85 : _ref$alpha,
          _ref$gravity = _ref.gravity,
          gravity = _ref$gravity === undefined ? 3.5 : _ref$gravity;

      var emitter = this.proton.pool.get(Proton.Emitter);

      if (!emitter.completed) {
        emitter.rate = new Proton.Rate(this.props.num ? new Proton.Span(this.props.num) : new Proton.Span(4, 9), new Proton.Span(1.6, 2.2));

        var radiusInit = mainEmitter ? new Proton.Radius(10, 110) : new Proton.Radius(3, radius);
        emitter.addInitialize(new Proton.Mass(1));
        emitter.addInitialize(radiusInit);
        emitter.addInitialize(new Proton.Life(3, 6));
        emitter.addInitialize(new Proton.Velocity(new Proton.Span(4, 6), new Proton.Span(-90, 90), "polar"));

        emitter.addBehaviour(new Proton.Alpha(alpha, 0.2));
        emitter.addBehaviour(new Proton.Color(color));
        emitter.addBehaviour(new Proton.Scale(1, 0.3));
        emitter.addBehaviour(new Proton.Rotate());
        emitter.addBehaviour(new Proton.Gravity(gravity));

        emitter.addBehaviour(this.customDeadBehaviour(canvas));
        emitter.addBehaviour(new Proton.CrossZone(new Proton.RectZone(0, 0, canvas.width, canvas.height), zone));
      }

      emitter.p.x = x;
      emitter.p.y = y;
      if (once === "once") emitter.emit("once");else emitter.emit();

      this.proton.addEmitter(emitter);

const emitter = new Proton.Emitter();
    emitter.rate = new Proton.Rate(
      this.props.num ? new Proton.Span(this.props.num) : new Proton.Span(100),
      new Proton.Span(0.05, 0.2)
    );

    emitter.addInitialize(new Proton.Mass(1));
    emitter.addInitialize(new Proton.Radius(1, 4));
    emitter.addInitialize(new Proton.Life(Infinity));

    const pointZone = new Proton.Position(
      new Proton.RectZone(0, 0, width, height)
    );
    emitter.addInitialize(pointZone);
    emitter.addInitialize(
      new Proton.Velocity(
        new Proton.Span(0.3, 0.6),
        new Proton.Span(0, 360),
        "polar"
      )
    );

    emitter.addBehaviour(new Proton.Alpha(Proton.getSpan(0.2, 0.9)));
    emitter.addBehaviour(new Proton.Color(this.props.color || "#333"));
    this.crossZoneBehaviour = new Proton.CrossZone(
      new Proton.RectZone(0, 0, width, height),
      "cross"
    );
    emitter.addBehaviour(this.crossZoneBehaviour);

    emitter.emit("once");
    emitter.damping = 0;

createProton(canvas, width, height) {
    this.proton = new Proton();
    const emitter = new Proton.Emitter();
    emitter.rate = new Proton.Rate(this.props.num ? this.props.num : 50);
    emitter.damping = 0;

    emitter.addInitialize(new Proton.Mass(1));
    emitter.addInitialize(new Proton.Radius(4, 70));
    emitter.addInitialize(
      new Proton.Velocity(new Proton.Span(2, 10), new Proton.Span(0), "polar")
    );
    emitter.addInitialize(
      new Proton.Position(
        new Proton.LineZone(0, canvas.height, canvas.width, canvas.height)
      )
    );

    const dis = 150;
    const crossZoneBehaviour = new Proton.CrossZone(
      new Proton.RectZone(
        0 - dis,
        0 - dis,
        canvas.width + 2 * dis,
        canvas.height + 2 * dis
      ),
      "cross"

createProton(canvas, width, height) {
    this.proton = new Proton();

    const emitter = new Proton.Emitter();
    emitter.damping = 0.008;
    emitter.rate = new Proton.Rate(this.props.num ? this.props.num : 50);
    emitter.addInitialize(new Proton.Mass(1));
    emitter.addInitialize(new Proton.Radius(5, 9));
    emitter.addInitialize(
      new Proton.Velocity(
        new Proton.Span(1.5),
        new Proton.Span(0, 360),
        "polar"
      )
    );
    emitter.addInitialize(
      new Proton.Position(new Proton.RectZone(0, 0, width, height))
    );

    const mouseInfo = {
      x: width / 2,
      y: height / 2
    };

    const attractionBehaviour = new Proton.Attraction(mouseInfo, 0, 0);
    const crossZoneBehaviour = new Proton.CrossZone(

createProton(canvas, width, height) {
    this.proton = new Proton();

    const emitter = new Proton.Emitter();
    emitter.damping = 0.008;
    emitter.rate = new Proton.Rate(this.props.num ? this.props.num : 250);
    emitter.addInitialize(new Proton.Mass(1));
    emitter.addInitialize(new Proton.Radius(4));
    emitter.addInitialize(
      new Proton.Velocity(
        new Proton.Span(1.5),
        new Proton.Span(0, 360),
        "polar"
      )
    );
    const mouseObj = {
      x: width / 2,
      y: height / 2
    };

    const attractionBehaviour = new Proton.Attraction(mouseObj, 0, 0);
    const crossZoneBehaviour = new Proton.CrossZone(
      new Proton.RectZone(0, 0, canvas.width, canvas.height),
      "cross"
    );
    emitter.addBehaviour(new Proton.Color("random"));

createProton(canvas, width, height) {
    this.proton = new Proton();

    const emitter = new Proton.Emitter();
    emitter.damping = 0.008;
    emitter.rate = new Proton.Rate(250);
    emitter.addInitialize(new Proton.Mass(1));
    emitter.addInitialize(new Proton.Radius(4));
    emitter.addInitialize(
      new Proton.Velocity(
        new Proton.Span(1.5),
        new Proton.Span(0, 360),
        "polar"
      )
    );
    const mouseObj = {
      x: width / 2,
      y: height / 2
    };

    const attractionBehaviour = new Proton.Attraction(mouseObj, 0, 0);
    const crossZoneBehaviour = new Proton.CrossZone(
      new Proton.RectZone(0, 0, canvas.width, canvas.height),
      "cross"
    );
    emitter.addBehaviour(new Proton.Color("random"));

createProton(canvas, width, height) {
    const context = canvas.getContext("2d");
    this.proton = new Proton();

    const emitter = new Proton.Emitter();
    emitter.rate = new Proton.Rate(
      this.props.num ? new Proton.Span(this.props.num) : new Proton.Span(4, 9),
      new Proton.Span(0.8, 1.3)
    );

    emitter.addInitialize(new Proton.Mass(1));
    emitter.addInitialize(new Proton.Radius(1, 50));
    emitter.addInitialize(new Proton.Life(5, 6));
    emitter.addInitialize(
      new Proton.Velocity(
        new Proton.Span(5, 8),
        new Proton.Span(30, 70),
        "polar"
      )
    );

    emitter.addBehaviour(new Proton.Alpha(1, 0));
    emitter.addBehaviour(
      new Proton.Color(["#36aaf3", "#fd769c", "#94ff22", "#ffa545", "#ffffff"])
    );
    emitter.addBehaviour(new Proton.Scale(0.7, 1));
    emitter.addBehaviour(new Proton.Gravity(3));
    emitter.addBehaviour(new Proton.Collision(emitter));
    emitter.addBehaviour(this.customDeadBehaviour(canvas));
    emitter.addBehaviour(
      new Proton.CrossZone(