Monkey Game Development：Beginner's Guide

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Time for action — acting on the different game modes

The last thing to add is the need to act to the game modes. We have three modes:

0=Start of game
1=Gameplay
2=GameOver

We want to direct and inform the player about what mode the game is in and how they can start it. Then if the victory conditions are achieved, we want to give a visual response.

The first mode is bound to a new method that we will create now. Create a new method called StartGame.
```
Method StartGame:Int()
```
We want to print a message only once; that is why we need the field modeMessage. If it is 0, then we can print this message. If we don't use such an approach, the message will be printed every time we call this method.
```
If modeMEssage = 0 Then
```

Now set messageMode to 1 and print a message:

modeMessage = 1
Print ("Press P to start the game")
Endif

In this method, we will also check if the P key was hit and set messageMode and gameMode accordingly.
```
If KeyHit(KEY_P) Then
modeMessage = 0
gameMode = 1 'mode = Game playing
Endif
```
Close off the method now.
```
Return True
End
```
The method for gameMode = 1 exists already; it's the UpdateGame method we have created and modified before.
For gameMode = 2, we will need another method that informs the player about the end of the game and who the winner is.
Create a new method called GameOver.
```
Method GameOver_Int()
```
Again, we will print some messages now, and we want to do this only once. Remember this method will be called at each frame as long we are in this game mode. So we check against modeMessage = 0 now.
```
If modeMessage = 0 Then
```
Now, set modeMessage to 1 and print an info message that the game has ended.
```
modeMessage = 1
Print ("G A M E O V E R")
```

Depending on who has more points, we will inform the player who won the game. For this, we will check if ePoints is equal to or greater than 10.

If ePoint >= 10 Then
Print ("Don't cry, the computer won! Next time try harder.")
Else
Print ("Congratulations, you won! It must be your lucky day.")
Endif

We want to inform the player now about what they can do next and close off this IF check.
```
Print ("Press P to restart the game")
Endif
```

As the player has the ability to restart the game, we will check now whether the P key was hit. Then, we will set the gameMode variable accordingly and also some position variables.

If KeyHit(KEY_P) Then
ePoints = 0
pPoints = 0
Print (ePoints + ":" + pPoints)
pY = 240.0 'player paddle Y pos
bX = 320.0 'ball Y pos
bY = 240.0 'ball Y pos
bdX = 3.5 'ball X speed
bdY = 1.5 'ball Y speed
eY[0] = 240.0 'enemy paddle 1 Y pos
eY[1] = 240.0 'enemy paddle 2 Y pos
modeMessage = 0
gameMode = 1
Endif

Close off this method now.
```
Return True
End
```
Not much is left to building our game. We have built the last two methods for the missing game modes and now call them when we need to. For this, we need to replace the OnUpdate method.
```
Method OnUpdate:Int()
```
To check which mode the game is in, we will use a Select statement this time and call the different methods according to the value of the field gameMode.
```
Select gameMode
Case 0
StartGame()
Case 1
UpdateGame()
Case 2
GameOver()
End
```
Close off our new OnUpdate method, now.
```
Return True
End
```
Save the game one last time and test it. For sure, the enemy paddles are not very competitive, but it will be a good practice for you to enhance this. If you want to compare your code to a final version, load up Pongo_final.Monkey.

What just happened?

Yeah, you can be proud of yourself. You have coded your first little game. It has everything a good game needs—good data structure, separate render and update methods, even collision detection, and a very simple computer AI.

Have a go hero — enhancing the computer AI

It will be good practice for you if you try to make the enemy paddles react more intelligently. Try to do this, perhaps as follows:

Maybe they should react on the Y speed of the ball somehow
Make the start of the ball more random
Give it a try and don't be afraid to change this. Just remember... save your code!