title: Draw oval with sphere in Opengl
body: <p>I want to draw an oval by projection the sphere on the screen (like rasterize).  Here is my code but it doesn't show anything on the screen. Should I use more functions to initialize the projection? Is this way possible to draw oval on screen by using sphere?</p>
  
  <pre><code>GLfloat xRotated, yRotated, zRotated;
  GLdouble radius=1;
  
  void display(void);
  void reshape(int x, int y);
  
  int main (int argc, char **argv)
  {
      glutInit(&amp;argc, argv); 
      glutInitWindowSize(800,800);
      glutCreateWindow("OVAL");
      zRotated = 30.0;
      xRotated=43;
      yRotated=50;
      glutDisplayFunc(display);
      glutReshapeFunc(reshape);
      glutMainLoop();
      return 0;
  }
  
  void display(void)
  {
      glMatrixMode(GL_PROJECTION);
      glOrtho(0.1, 1.0, 0.1, 1.0, -1.0, 1.0);
      glClear(GL_COLOR_BUFFER_BIT);
      glLoadIdentity();
      glTranslatef(0.0,0.0,-5.0);
      glColor3f(0.9, 0.3, 0.2); 
      glRotatef(xRotated,1.0,0.0,0.0);
      glRotatef(yRotated,0.0,1.0,0.0);
      glRotatef(zRotated,0.0,0.0,1.0);
      glScalef(1.0,1.0,1.0);glutSolidSphere(radius,20,20);
      glFlush();        
      }
  
  void reshape(int x, int y)
  {
      if (y == 0 || x == 0) return;   
      glMatrixMode(GL_PROJECTION);  
      glLoadIdentity(); 
      gluPerspective(39.0,(GLdouble)x/(GLdouble)y,0.6,21.0);
      glMatrixMode(GL_MODELVIEW);
      glViewport(0,0,x,y);  
  } 
  </code></pre>