// constructor adds Managers to the GameManager and sets state and direction
public GameManager(LevelManager levelManager) {
GameObject.OnDeathListener += DeathListener;
LevelManager = levelManager;
InputManager = new InputManager();
CollisionManager = new CollisionManager();
SpawnManager = new SpawnManager();
GameState = EGameState.Running;
OnGameStateChangedListener(GameState);
CurrentDirection = EDirection.South;
OnDirectionChangedListener(CurrentDirection);
GameLoop();
}