Open Engine.h, add an include for our new class, declare an instance of the new HUD class, and also declare and initialize two new member variables that will keep track of how often we update the HUD. As we have learned in the two previous projects, we don't need to do this for every frame.

Add the highlighted code to Engine.h:

#pragma once 
#include <SFML/Graphics.hpp> 
#include "TextureHolder.h" 
#include "Thomas.h" 
#include "Bob.h" 
#include "LevelManager.h" 
#include "SoundManager.h" 
#include "HUD.h" 
 
using namespace sf; 
 
class Engine 
{ 
private: 
   // The texture holder 
   TextureHolder th; 
 
   // Thomas and his friend, Bob 
   Thomas m_Thomas; 
   Bob m_Bob; 
 
   // A class to manage all the levels 
   LevelManager m_LM; 
 
   // Create a SoundManager 
   SoundManager m_SM; 
 
   // The Hud   Hud m_Hud;
   int...