! Document name: ╡Ikkuna1

! ╡Ikkuna1
! (c) M.A.D. Severi Virolainen 910607

prism_ 10,d,
      -a/2,0,15,
      -a/2,b,15,
       a/2,b,15,
       a/2,0,15,
      -a/2,0,-1,

      -a/2+c,c,  15,
      -a/2+c,b-c,15,
       a/2-c,b-c,15,
       a/2-c,c,  15,
      -a/2+c,c,  -1
if e<=0 then 99
addz d/3
set material e
prism_ 4,d/3,
      -a/2+c,c,  15,
      -a/2+c,b-c,15,
       a/2-c,b-c,15,
       a/2-c,c,  15
99:
del top
end