/*
 * main.cpp
 *
 * This file is supposed to test whether or not
 * my code actually works.
 * 
 * compiles with: g++ -g -Wall -Weffc++ -pedantic -lm -lglut -lGLEW -lGLU -lexpat main.cpp -o glewtester
 * produces: int main(int argc, char* argv[])
 *	GLEW SEEMS TO BE WORKING.  No error
 *	EMERGENCY! glGenBuffers is not properly initialized!
 *	glGetString(GL_RENDERER) = Mesa DRI Intel(R) 945GM GEM 20091221 2009Q4 x86/MMX/SSE2
 *	0
 *	*buf declared.
 *	EMERGENCY! glGenBuffers is not properly initialized!
 *	Segmentation fault
 * 
 */

#include<iostream>
#include<fstream>
#include<string>

#include<GL/glew.h>
#include<GL/glut.h>

class Pixel
{
	private:
		int	r;	//The Red value
		int	g;	//The Green value
		int	b;	//The Blue value

	public:
		Pixel(): r(0), g(0), b(0)	{}
		Pixel(int R, int G, int B): r(R), g(G), b(B) {}

		~Pixel(){}
		
		void	setR(int R)	{r = R;}
		void	setG(int G)	{g = G;}
		void	setB(int B)	{b = B;}

		const	int	R()	{return r;}
		const	int	G()	{return g;}
		const	int	B()	{return b;}
};


const void init()
{
#if DEBUG == 1
	std::cerr << "Width = " << img.getWidth() << "	Height = " << img.getHeight() << std::endl;
#endif

	glutInitDisplayMode( GLUT_DOUBLE | GLUT_RGBA );		
	glutInitWindowPosition(0,0);			
	glutInitWindowSize(640, 480);			
	glutCreateWindow("GLEW TESTER");
	gluOrtho2D(0,640,0,480);
	glClearColor(0,0,0,0);
	GLenum err = glewInit();
	if(GLEW_OK != err)
	{
		//GLEW Failed
		std::cerr << "ERROR STRING = " << glewGetErrorString(err) << std::endl;
	}
	else
		std::cerr << "GLEW SEEMS TO BE WORKING.  " << glewGetErrorString(err) << std::endl;
	if(glGenBuffers == NULL)
		std::cerr << "EMERGENCY! glGenBuffers is not properly initialized!" << std::endl;

	std::cerr << "glGetString(GL_RENDERER) = " << glGetString(GL_RENDERER) << std::endl;
	std::cerr << (int) glewGetExtension("ARB_vertex_buffer_object") << std::endl;
}

const void drawSquare()
{
	int width = 640;
	int height = 480;
	
	Pixel *pix = new Pixel[width * height];

	for(int i = 0; i < (width*height); i++)
	{
		pix[i].setR(i % (width / 256));
		pix[i].setG(i % (height/ 256));
		pix[i].setB(i % ((width * height) / 256));
	}

	GLuint verts[][5] = {{0,0,0,0,0}, {width,0,0,width,0}, {width,height,0,width,height}, {0,height,0,0,height}};
	GLuint *buf = new GLuint[5];
	GLsizei n = 1;

	std::cerr << "*buf declared." << std::endl;

	if(glGenBuffers == NULL)
		std::cerr << "EMERGENCY! glGenBuffers is not properly initialized!" << std::endl;

	glGenBuffers(n, buf);
	std::cerr << "Buffers generated." << std::endl;
	glBindBuffer(GL_ARRAY_BUFFER, buf[0]);

	glBufferData(GL_ARRAY_BUFFER, 80, verts, GL_STREAM_DRAW);

	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);


	
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_INT, pix);
}




const void draw()
{
	glClear(GL_COLOR_BUFFER_BIT);

	drawSquare();

	glutSwapBuffers();
}



int main(int argc, char* argv[])
{
	std::cout << "int main(int argc, char* argv[])" << std::endl;

	glutInit(&argc, argv);
	init();

	draw();

	//glutMainLoop();
	
	return 0;

}