%% PhS
%% 

50 setxunit
-5 5  setxrange
-2.5 2.5 setyrange



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% procédures
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


/bddroite {
8 dict begin
	/kd exch def
	/kg exch def
	/By exch def
	/Bx exch def
	/B {Bx By} def
	/Ay exch def
	/Ax exch def
	/A {Ax Ay} def
	gsave
	[A A B vecteur kg mulv addv A A B vecteur kd mulv addv] ligne
	grestore
end
	} def




%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% definition d'une couleur
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/coul1 {120 255 div 70 255 div 9 255 div setrgbcolor} def



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% definition des points
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/a {3} def
/c {2.5} def
/b {a a mul c c mul sub sqrt} def
/e {c a div} def
/Kx {a e div} def
/K {Kx neg 0} def
/K+ {K 0 6 addv} def
/K- {K 0 -6 addv} def
/Kp {Kx 0} def
/Kp+ {Kp 0 6 addv} def
/Kp- {Kp 0 -6 addv} def
/O {0 0} def
/F {c neg 0} def
/Fp {c 0} def
/S1 {a neg 0} def
/S2 {a 0} def
/B {0 b} def

/xdet {settvar t cos a mul} def
/ydet {settvar t sin b mul} def


/Mx {120 xdet} def
/My {120 ydet} def
/M {Mx My} def
/H {M K K+ orthoproj} def
/Hp {M Kp Kp+ orthoproj} def


/bissec {F M Fp bissectrice} def
/bixx {bissec O S2 interdroite}def
/Mbixx {M bixx vecteur} def
/T {bissec M perp  Kp Kp+ interdroite} def
/MT {M T vecteur} def


/theta1 {c neg a div arccos} def
/Fcons1 {theta1 xdet theta1 ydet} def
/Fcons2 {theta1 neg xdet theta1 neg ydet} def




%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% traces
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
/coul1 {188 255 div 128 255 div 9 255 div setrgbcolor} def

1.2 setlinewidth
[O F Fp S1 S2 K Kp M] points
[K -0.5 0 addv Kp 0.5 0 addv] ligne
[O 0 -6.5 addv O 0 6.5 addv] ligne

noir
0 360 settrange
{xdet} {ydet} courbeparam

vert
[K+ K-] ligne
[Kp+ Kp-] ligne


orange
[F M Fp] ligne



F M bixx 0.5 (=) tripointarc
bixx M Fp 0.7 (=) tripointarc


coul1
continu
M bixx -0.5 1.5 bddroite
M T -1.3 1.8 bddroite
T M bixx M vecteur M addv angledroit


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% texte
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

setTimesItalic
noir
  (O) O [1.5 dup] dltext
  (F) F [1.5 dup] drtext
  (F') Fp [1.5 dup] dltext
  (M) M -0.3 0.15 addv [1.5 dup] cctext


noir
<latex>
$ S_1 $
</latex>
S1 [1.5 dup] dltexlabel


<latex>
$ S_2 $
</latex>
S2 [1.5 dup] drtexlabel




vert
  (K) K [1.5 dup] dltext
  (K') Kp [1.5 dup] drtext


<latex>
$ \mathcal{D} $
</latex>
(D) K 0 -2 addv [1.5 dup] cltexlabel


<latex>
$ \mathcal{D'} $
</latex>
(D) Kp 0 -2 addv [1.5 dup] crtexlabel