void init() {
  glDisable(GL_LIGHTING);
  glShadeModel(GL_FLAT);
  // Use a simple non-distorting (letterbox) perspective camera with
  // 90 degree fovy on a 4:3 shaped window, so the frustum is based on
  // the horizontal, which makes things just a little more complex.
  // Since we can't move the camera around without using TW, we'll
  // place the camera above and to the right of the barn, so you can
  // see the front, right side, and the roof.
  GLfloat BBheight = barnHeight+barnWidth/2.0;
  GLfloat BBdepth = barnLength;
  GLfloat BBwidth = barnWidth;
  GLfloat BBradius = 0.5*sqrt(BBheight*BBheight+BBdepth*BBdepth+BBwidth*BBwidth);
  GLfloat EyeRadius = BBradius*sqrt(2);
  // Compute Center of BB
  GLfloat CenterX = BBwidth/2;
  GLfloat CenterY = BBheight/2;
  GLfloat CenterZ = -BBdepth/2;
  // Place Eye equally far from Center along each axis
  GLfloat EyeOrthoDist = EyeRadius/sqrt(3);
  GLfloat EyeX = CenterX+EyeOrthoDist;
  GLfloat EyeY = CenterY+EyeOrthoDist;
  GLfloat EyeZ = CenterZ+EyeOrthoDist;
  EyeX = CenterX;
  EyeY = CenterY;
  EyeZ = CenterZ+EyeRadius;
  GLfloat AtX = CenterX;
  GLfloat AtY = CenterY;
  GLfloat AtZ = CenterZ;
  GLfloat fovy = 90;
  GLfloat aspectRatio = 4.0/3.0;
  GLfloat near = EyeRadius - BBradius;
  GLfloat far  = EyeRadius + BBradius;
  
  // Some debugging print statements:
  printf("BBradius = %f, EyeRadius =%f\n",BBradius,EyeRadius);
  printf("Center = (%f,%f,%f)\n",CenterX,CenterY,CenterZ);
  printf("aspect ratio = %f\nEyeRadius = %f, near=%f far=%f\nVRP=(%f,%f,%f)\nAt=(%f,%f,%f)\n",
         aspectRatio,EyeRadius,near,far,EyeX,EyeY,EyeZ,AtX,AtY,AtZ);
  printf("EyeOrthoDist = %f\n",EyeOrthoDist);

  near = 0.1;
  far = 1000;
  EyeY = -5;
  EyeZ = 30;
  
  // Some debugging print statements:
  printf("BBradius = %f, EyeRadius =%f\n",BBradius,EyeRadius);
  printf("Center = (%f,%f,%f)\n",CenterX,CenterY,CenterZ);
  printf("aspect ratio = %f\nEyeRadius = %f, near=%f far=%f\nVRP=(%f,%f,%f)\nAt=(%f,%f,%f)\n",
         aspectRatio,EyeRadius,near,far,EyeX,EyeY,EyeZ,AtX,AtY,AtZ);
  printf("EyeOrthoDist = %f\n",EyeOrthoDist);

  // Okay, finally ready for the OpenGL calls
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluPerspective(fovy,aspectRatio,near,far);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  gluLookAt(EyeX,EyeY,EyeZ,AtX,AtY,AtZ,0,1,0);
}