Time for action – coding the GameLayer interface

GameLayer is the main container in our game.

1. Follow the steps to add a new file to your Classes folder. This is a C++ file called GameLayer.

2. Select your GameLayer.h. Just below the first define preprocessor command, add:

   #define GOAL_WIDTH 400

3. We define the width of the goals in pixels.

4. Next, add the declarations for our sprites and our score text labels:

   #include "cocos2d.h"
   #include "GameSprite.h"
   
   using namespace cocos2d;
   
   class GameLayer : public Layer
   {
       GameSprite* _player1;
       GameSprite* _player2;
       GameSprite* _ball;
       
       Vector<GameSprite*> _players;
       Label* _player1ScoreLabel;
       Label* _player2ScoreLabel;

   We have the GameSprite objects for two players (the weird looking things called mallets), and the ball (called a puck). We'll store the two players in a Cocos2d-x Vector. We also have two text labels to display the score for each player.

5. Declare a variable to store the screen size. We'll use this a lot for positioning...