Vector3 eye(0.0f, 0.14f, 0.23f);
   Vector3 gaze(0.0f, 0.0f, -1.0f);
   Vector3 up(0.0f, 1.0f, 0.0f);

   float aper   =  0.0f;
   float left   = -0.5f;
   float right  =  0.5f;
   float top    =  0.5f;
   float bottom = -0.5f;
   float dist   =  1.1f;