public void join(PlaPointFloat p_point){
  lx=Math.min(p_point.v_x,lx);
  ly=Math.min(p_point.v_y,ly);
  rx=Math.max(rx,p_point.v_x);
  uy=Math.max(uy,p_point.v_y);
  double tmp=p_point.v_x - p_point.v_y;
  ulx=Math.min(ulx,tmp);
  lrx=Math.max(lrx,tmp);
  tmp=p_point.v_x + p_point.v_y;
  llx=Math.min(llx,tmp);
  urx=Math.max(urx,tmp);
}

public void join ( PlaPointFloat p_point ) { lx = Math . min ( p_point . v_x , lx ) ; ly = Math . min ( p_point . v_y , ly ) ; rx = Math . max ( rx , p_point . v_x ) ; uy = Math . max ( uy , p_point . v_y ) ; double tmp = p_point . v_x - p_point . v_y ; ulx = Math . min ( ulx , tmp ) ; lrx = Math . max ( lrx , tmp ) ; tmp = p_point . v_x + p_point . v_y ; llx = Math . min ( llx , tmp ) ; urx = Math . max ( urx , tmp ) ; }
enlarges the octagon so that it contains p_point
