Your First Game – Air Hockey - Cocos2d-x by Example Beginner's Guide - page 71

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:
Size _screenSize;