// Use this for initialization
    public override void Start()
    {
        //NOTE: set experiment_name before calling base.Start()
        experiment_name = "mouse_screenspace_select";
        input_name      = "mouse";
        interface_name  = "mouse_screenspace";   // we're just moving the
                                                 //  mouse cursor
        task_name       = "select";

        base.Start();

        selections = new Record_Selection(  data_file_prefix + "selections",
                                            participant_id,
                                            input_name,
                                            interface_name,
                                            task_name
                                         );

        // build our interface action logic
        selectAction = new Select_MouseClick_Raycast();
        selectAction.register(this.onSelect);

        task.start();
    }
    // Use this for initialization
    public override void Start()
    {
        //NOTE: set experiment_name before calling base.Start()
        experiment_name = "xbox_screenspace_select";
        input_name      = "xbox_controller";
        interface_name  = "mouse_screenspace";   // we're just moving the
        //  mouse cursor
        task_name       = "select";

        base.Start();

        selections = new Record_Selection(data_file_prefix + "selections",
                                          participant_id,
                                          input_name,
                                          interface_name,
                                          task_name
                                          );

        // build our interface action logic
        action = new Select_Xbox_Raycast();
        action.register(delegate(GameObject selected) { this.onSelect(selected); });

        task.start();
    }