! @ PR:P_CORNER.GREG Icorner Dx Dy 
! Mask Dx % by Dy % of the current box near corner Icorner 
! 
define real user[4] poly[4,2] dx dy eps 
! 
let dx user_xmax-user_xmin 
let dy user_ymax-user_ymin 
let eps 1e-2 
if (&1.eq.1) then 
  let user[1] user_xmin+eps*dx 
  let user[2] user_ymin+eps*dy 
  let user[3] user_xmin+&2*dx 
  let user[4] user_ymin+&3*dy 
else if (&1.eq.2) then 
  let user[1] (user_xmax+user_xmin-&2*dx)|2 
  let user[2] user_ymin+eps*dy 
  let user[3] (user_xmax+user_xmin+&2*dx)|2 
  let user[4] user_ymin+&3*dy 
else if (&1.eq.3) then 
  let user[1] user_xmax-eps*dx 
  let user[2] user_ymin+eps*dy 
  let user[3] user_xmax-&2*dx 
  let user[4] user_ymin+&3*dy 
else if (&1.eq.4) then 
  let user[1] user_xmin+eps*dx 
  let user[2] (user_ymin+user_ymax-&3*dy)|2 
  let user[3] user_xmin+&2*dx 
  let user[4] (user_ymin+user_ymax+&3*dy)|2 
else if (&1.eq.6) then 
  let user[1] user_xmax-eps*dx 
  let user[2] (user_ymin+user_ymax-&3*dy)|2 
  let user[3] user_xmax-&2*dx 
  let user[4] (user_ymin+user_ymax+&3*dy)|2 
                                ! 
else if (&1.eq.7) then 
  let user[1] user_xmin+eps*dx 
  let user[2] user_ymax-eps*dy 
  let user[3] user_xmin+&2*dx 
  let user[4] user_ymax-&3*dy 
else if (&1.eq.8) then 
  let user[1] (user_xmax+user_xmin-&2*dx)|2 
  let user[2] user_ymax-eps*dy 
  let user[3] (user_xmax+user_xmin+&2*dx)|2 
  let user[4] user_ymax-&3*dy 
else if (&1.eq.9) then 
  let user[1] user_xmax-eps*dx 
  let user[2] user_ymax-eps*dy 
  let user[3] user_xmax-&2*dx 
  let user[4] user_ymax-&3*dy 
endif 
let poly user[1] user[3] user[3] user[1] user[2] user[2] user[4] user[4] 
greg1\set coordin user 
polygon poly /variable 
polygon /fill 7