/* CS 365 Spring 2011
 * Lab 1 skeleton program
 */

/* Notice that glut.h brings in gl.h, glu.h */
#include <GL/glut.h>
#include <stdio.h>
#include <math.h>

/* Convert degrees to radians */
#ifndef M_PI
   #define M_PI 3.141593
#endif
#define TORAD(deg) (3.141593 * (deg) / 180.0)

/* Global variables */
float eyex = 5.0;
float eyey = 5.0;
float eyez = 10.0;
float atx = 0.0;
float aty = 0.0;
float atz = 0.0;


/*
   Draw one axis, including tick marks.

     axno  0=x, 1=y, 2=z
     leng  length from origin to each end of axis
*/
void draw_axis(int axno, int leng) {
    /* Your code here. */
}

/* Draw all three axes */
void axes(void) {
    draw_axis(0, 5);
    draw_axis(1, 5);
    draw_axis(2, 5);
}

/* Draw an open sphere at the origin of radius r */ 

void sphere_open(double r) {

}

/*
   display callback
*/
void display() {
    /* Clear frame buffer */
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    /* Set up the synthetic camera in the Modelview matrix with gluLookAt() */

    /* Draw axes */
    axes();

    glutWireTeapot(0.5);
    /* Then draw open sphere */

    /* Make it all visible */
    glFlush();
    glutSwapBuffers();
}

/*   Special key callback */
void specialkey(int keypressed, int x, int y) {
    
    /* Need to redisplay at the end */
    glutPostRedisplay();
}

/*   Regular key callback */
void key(unsigned char keypressed, int x, int y){
    switch (keypressed) {

    /* e or E exits */
    case 'e':
    case 'E':
        exit(0);
    }
}
   
/* Reshape handler */ 
void reshape(int w, int h){
   /* Set viewport based on w and h */
   /* Switch to Projection matrix */
   /* Set Projection matrix using glFrustum */
   /* Switch back to Modelview matrix */
   /* Post a redisplay */

   /* Here is a simplest imaginable version with an orthographic projection */
   glViewport(0, 0, 500, 500);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
   glutPostRedisplay();
}

/* Redraw on window maximize, etc. */
void windowstatus(int state) {
   if (! (state == GLUT_HIDDEN || state == GLUT_FULLY_COVERED))
       glutPostRedisplay();
}

/* Main program */
void main(int argc, char * argv[]) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(500, 500);
    glutCreateWindow("CS 365 Lab 1: MYNAME");
    glutReshapeFunc(reshape);
    glutWindowStatusFunc(windowstatus);
    glutDisplayFunc(display);
    glutSpecialFunc(specialkey);
    glutKeyboardFunc(key);
    glEnable(GL_DEPTH_TEST); 
    glutMainLoop();
}