void AddUnit(UnitMain unit)
 {
     DeselectNode();
     SetMode(ControlMode.None);
     selected_units.Add(unit);
     unit.SetSelected(true);
 }
    public void OnCarDead(UnitMain unit)
    {
        selected_units.Remove(unit);

        if (GameObject.FindGameObjectsWithTag("Unit").Length == 1)
        {
            SetGameover();
        }
    }
 public void AddCar(UnitMain unit)
 {
     unit.OnDeadEvent += OnCarDead;
 }
 void SelectUnit(UnitMain unit)
 {
     DeselectUnits();
     AddUnit(unit);
 }