/*
 *  cube.c
 *  This program demonstrates a single modeling transformation,
 *  glScalef() and a single viewing transformation, gluLookAt().
 *  A wireframe cube is rendered.
 */
#include "glut.h"
#include <stdlib.h>

void init(void) 
{
  glClearColor (0.0F, 0.0F, 0.7F, 1.0F);
}



void display(void)
{
  glClear (GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  
  /* modeling transformation */ 
  glLoadIdentity ();             /* clear the matrix */
  gluLookAt (3.0, 5.0, 6.0,  // eye
             1.0, 1.0, 1.0,  // ref
             0.0, 1.0, 0.0); // up

  /* desenha um elipsoide */
  glTranslatef(1.0F, 1.0F, 1.0F);
  glScalef (0.3F, 0.4F, 0.5F);      
  glColor3f (1.0F, 1.0F, 0.0F);
  glutWireSphere (1.0,8,8);
  glFlush ();
}

void reshape (int w, int h)
{
   glViewport (0, 0, (GLsizei) w, (GLsizei) h); 
   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();
   glFrustum (-0.4, 0.4, -0.4, 0.4, 1.5, 20.0);
   glMatrixMode (GL_MODELVIEW);
}

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
      case 27:
         exit(0);
         break;
   }
}

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
   glutInitWindowSize (500, 500); 
   glutInitWindowPosition (100, 100);
   glutCreateWindow (argv[0]);
   init ();
   glutDisplayFunc(display); 
   glutReshapeFunc(reshape);
   glutKeyboardFunc(keyboard);
   glutMainLoop();
   return 0;
}