#include	<GL/glut.h>
#include	<GL/gl.h>
#include	<stdio.h>

#define		RED 0
#define		GREEN 1
#define		BLUE 2

#define		AMBIENT 0
#define		DIFFUSE 1
#define     SPECULAR 2
#define     SHINE 3

int			width,height;
int			cmode=RED, rmode=AMBIENT;



GLfloat		light_position[] = {0.0,10.0,10.0,0.0};
GLfloat		light_ambient[] = {1.0,1.0,1.0,1.0};
GLfloat		light_diffuse[] = {1.0,1.0,1.0,1.0};
GLfloat		light_specular[] = {1.0,1.0,1.0,1.0};

GLfloat		sphere[]={.20,.10,0.0,1.0,.20,.20,.05,1.0,.80,.80,.80,1.0};
GLfloat		shine_factor=50.0;


	

void init(void)
{
	int i;

	/*  background color		*/
	glClearColor(0.0,0.0,0.0,0.0);

	/*	shade model				*/
	glShadeModel(GL_SMOOTH);

	/*  enable z-buffering		*/
	glEnable(GL_DEPTH_TEST);

/*  lighting				*/
	glLightfv(GL_LIGHT0, GL_POSITION, light_position);
	glLightfv(GL_LIGHT0,GL_AMBIENT,light_ambient);
	glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
	glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
	glEnable(GL_LIGHTING);
	glEnable(GL_LIGHT0);

}



void display(void)
{

	
	
	glClear(GL_COLOR_BUFFER_BIT  | GL_DEPTH_BUFFER_BIT);	
	glLoadIdentity();

	/* reset material properties */
	glMaterialfv(GL_FRONT, GL_AMBIENT, &sphere[0]);
	glMaterialfv(GL_FRONT, GL_DIFFUSE, &sphere[4]);	
	glMaterialfv(GL_FRONT, GL_SPECULAR, &sphere[8]);
	glMaterialf(GL_FRONT, GL_SHININESS, shine_factor);

	/* draw sphere */
	glTranslatef(0.0,0.0,-500.0);
	glutSolidTeapot(125.00);	


	glFlush();
	glutSwapBuffers();

	return;
}


void reshape(int w, int h)
{
	width=w;
	height=h;
	glViewport(0,0,(GLsizei) w, (GLsizei)h); 
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho((float) (-w)/2.0, (float) w/2.0,(float) (-h)/2.0, (float) h/2.0, 10.0, 1000.0);
	

	glMatrixMode(GL_MODELVIEW);

	
}



void keyboard(unsigned char key, int x, int y)
{

	// set color mode to R,G, or B and reflection mode to 
	// ambient, diffuse, specular, or shine

	switch(key) {

	case 'r':	
	case 'R':	cmode = RED;
				break;
	case 'b':
	case 'B':	cmode = BLUE;
				break;

	case 'g':	
	case 'G':	cmode = GREEN;
				break;


	case '1':	rmode = AMBIENT;
				break;
	
	case '2':	rmode = DIFFUSE;
				break;

	case '3':	rmode = SPECULAR;
				break;

	case 's':
	case 'S':	rmode = SHINE;
				break;

	case 'p':
	case 'P':	printf("reflection/color	red		green		blue\n");
				printf("ambient			%1.2f		%1.2f		%1.2f\n",sphere[0],sphere[1],sphere[2]);
				printf("diffuse			%1.2f		%1.2f		%1.2f\n",sphere[4],sphere[5],sphere[6]);
				printf("specular		%1.2f		%1.2f		%1.2f\n",sphere[8],sphere[9],sphere[10]);
				printf("shininess		%3.0f\n",shine_factor);
				break;
	
	default:	break;
	}

}
	





void mouse(int button, int state, int x, int y)
{
	
	if (button==GLUT_LEFT_BUTTON && state==GLUT_DOWN) {
		if (rmode !=SHINE && sphere[rmode*4 + cmode]>= 0.05)
				sphere[rmode*4 + cmode] -= .05;
		if (rmode==SHINE && shine_factor >= 3.0)
				shine_factor -=3;
	}
	if (button==GLUT_RIGHT_BUTTON && state == GLUT_DOWN) {
		
		if (rmode != SHINE && sphere[rmode*4 + cmode]<=.95)
				sphere[rmode*4 + cmode] += .05;
		if (rmode == SHINE)
				shine_factor += 3;
	}
	glutPostRedisplay();
};





main(int argc, char* argv[])
{


	width=height=500;
	glutInit(&argc,argv);
	glutInitWindowPosition(100,100);
	glutInitWindowSize(width,height);
	glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH );


	glutCreateWindow("MATERIAL EFFECTS");
	init();
	
	glutReshapeFunc(reshape);
	glutMouseFunc(mouse);
	glutDisplayFunc(display);
	glutKeyboardFunc(keyboard);
	glutMainLoop();
	

	

	return(1);
}