glPushMatrix ();
glRotatef (view_rotx, 1.0, 0.0, 0.0);
glRotatef (view_roty, 0.0, 1.0, 0.0);
glRotatef (view_rotz, 0.0, 0.0, 1.0);
glPushMatrix ();
glRotatef (view_rotx, 1.0, 0.0, 0.0);
glRotatef (view_roty, 0.0, 1.0, 0.0);
glRotatef (view_rotz, 0.0, 0.0, 1.0);