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#ifndef PONG_H_
#define PONG_H_
 
#include <iostream>
#include <gl/glew.h>
#include <sdl/SDL.h>
#include <sdl/SDL_ttf.h>
 
class Pong
{
private:
        //Width and the Height of the Window
	int _width, _height;
 
        //This is it, THE screen, this is effectively what we will be rendering everything to.
	SDL_Surface *_screen;
 
	bool InitialiseGraphics();
	void InitialiseGeometry();
 
public:
 
	Pong(int width, int height);
 
	bool Initialise();
 
	void Run();
 
	void Uninitialise();
 
};
 
#endif /* PONG_H_ */

#include <cstring>
#include "Pong.h"
 
using namespace std;
 
Pong::Pong(int width, int height)
{
	_width = width;
	_height = height;
}
 
bool Pong::Initialise()
{
	if (!InitialiseGraphics())
		return false;
 
	InitialiseGeometry();
 
	return true;
}
 
void Pong::InitialiseGeometry()
{
 
}

bool Pong::InitialiseGraphics()
{
	//We only want video, no need for audio/network or even the CD-Rom...
	if (SDL_Init(SDL_INIT_VIDEO) != 0)
		return false;
 
	//We want to double buffer the screen
	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
 
	//Create the actual screen for SDL/OpenGL to render to
	_screen = SDL_SetVideoMode(_width, _height, 32, SDL_OPENGL);
 
	std::cout << "SDL Initialised" << std::endl;
 
	glEnable(GL_TEXTURE_2D);
 
	//Set the ViewPort (what we can see) to the same resolution as the actual screen, in this case, 640x480
	glViewport(0, 0, _width, _height);
 
	//Clear the screen again
	glClear(GL_COLOR_BUFFER_BIT);
 
	//Set the Matrix into Projection mode
	glMatrixMode(GL_PROJECTION);
 
	//Load the Projection Matrix
	glLoadIdentity();
 
	//Create an Orthogonal matrix, meaning 2D basically, so we only really work in X and Y
	glOrtho(0, (float) _width, (float) _height, 0, -1.0f, 1.0f);
 
	//Set the Matrix back into Model View mode
	glMatrixMode(GL_MODELVIEW);
 
	//Load the ModelView Matrix
	glLoadIdentity();
 
	//Set the Clear Colour, this is the colour the screen will be cleaered to every time we call glClear(...);
	glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
 
	return true;
}

void Pong::Run()
{
        //This is a bit we can just use to determine if we want to continue rendering or not
	bool isRunning = true;
        //This is where SDL will provide us with an event, so we can check for KB input, etc
	SDL_Event theEvent;
 
        //Loop forever, until isRunning is false.
	while (isRunning)
	{
                //Poll through as many events as there are available from SDL
		while (SDL_PollEvent(&theEvent))
		{
                        //Check the key that was pressed down...
			switch (theEvent.key.keysym.sym)
			{
			case SDLK_ESCAPE:
                                //If they pushed the ESC key, lets stop the main loop from looping, they want to quit...
				isRunning = false;
				break;
			default:
				break;
			}
		}
 
                //Clear the screen to the colour we defined in the InitialiseGraphics method earlier.
		glClear(GL_COLOR_BUFFER_BIT);
 
	        //This is where everything will get rendered....eventually
 
                //Swap the buffers around, so we can now show one and draw to another, hence Double Buffering
		SDL_GL_SwapBuffers();
	}
}

void Pong::Uninitialise()
{
        //Free the Screen surface, basically unload it from memory, we have no need for it now
	SDL_FreeSurface(_screen);
 
        //Tell SDL we are leaving, it should pack up it's bits and come with us.
	SDL_Quit();
}

#include "Pong.h"
 
int main(int argc, char *argv[])
{
        //Create a new instance of our Pong class
        Pong myPong(640, 480);
 
        //Try an Initialise the SDL and OpenGL APIs
        if (myPong.Initialise())
        {
                //Remember this method? This will block the thread until the game is over.
                myPong.Run();
 
                //Free all those resources we used up.
                myPong.Uninitialise();
        }
}

g++ -O2 -g -Wall -fmessage-length=0   -c -o src/main.o src/main.cpp
g++ -o Pong	 src/main.o -lSDL -lGL -lSDL_ttf
src/main.o: In function `main':
/your_path_here/Pong/src/main.cpp:12: undefined reference to `Pong::Pong(int, int)'

OBJS =          src/main.o

OBJS =          src/main.o src/Pong.o

OBJS =          main.o

OBJS =          main.o Pong.o

g++ -O2 -g -Wall -fmessage-length=0   -c -o src/main.o src/main.cpp
g++ -O2 -g -Wall -fmessage-length=0   -c -o src/Pong.o src/Pong.cpp
g++ -o Pong	 src/main.o src/Pong.o -lSDL -lGL -lSDL_ttf

./Pong