-1 3 setxrange
-1 4 setyrange
14 setfontsize 
/l 2 def
/L 3 def
/x 4 3 div def

/A {0 0} def
/B {A l 0 addv} def
/C {B 0 L addv} def
/D {A 0 L addv} def

/P {A 0 x addv} def
/M {A x 0 addv} def
/N {P x 0 addv} def
/Q {B  0 x addv} def
/R {D x 0 addv} def

/fillstyle {noir hachure} def
gsave
   blanc
   N C frame*
   A N frame*
grestore

medium setlinewidth
gsave
   pointilles
   [R M] ligne
   [P Q] ligne
grestore
[A B C D] polygone

setTimesItalic
   (A) A dltext
   (B) B drtext
   (C) C urtext
   (D) D ultext
   (P) P dltext
   (Q) Q drtext
   (R) R ultext
   (M) M dltext
   (N) N dltext