Time for action – scoring

To implement the scoring system for Mars Runner, perform the following steps:

1. 1. Add two fields to the MarsRunnerPlayScreen class as follows:

   float score = 0;
   SpriteFont font;

2. 2. In the LoadContent() method of the MarsRunnerPlayScreen class, initialize the font field as follows:

   font = content.Load<SpriteFont>("gamefont");

3. 3. In the Update() method of the MarsRunnerPlayScreen class, inside the if statement that checks playerPosition, increment the player's score, and add an else condition that ends the game if the player has reached the end of the track. The new if statement should read as follows:

   if (playerPosition < 2880)
   {
       playerPosition += 15 * elapsed;
       skybox.Rotation += 0.1f * elapsed;
       score += elapsed;
   }
   else
   {
       EndGame();
   }

4. 4. Still in the Update() method, inside the if statement checking for player hits on enemies, increase the player's score just after the call to enemy.CrashSaucer() as follows:

   score += 100;

5. 5. In the Draw() method of...