Source
%% PhS
%%

40 setxunit
-3 7  setxrange
-2.5 5.5 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 des points
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/p {1.5} def
/e {1} def
/F {0 0} def
/Kx {p e div neg} def
/K {Kx 0} def
/D {Kx -2.2} def
/S {p -2 div 0} def
/H1 {-8 0} def
/H2 {8 0} def
/V1 {Kx -3.5} def
/V2 {Kx 6} def

/rhox {settvar t cos e mul neg 1 add 1 exch div p mul t cos mul} def
/rhoy {settvar t cos e mul neg 1 add 1 exch div p mul t sin mul} def

/ThM {60} def
/My {ThM rhoy} def
/M {ThM rhox My} def
/H {Kx My} def

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

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

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% tracés
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1.3 setlinewidth
continu
[K F] points
[H1 H2] ligne
[V1 V2] ligne

coul1
20 340 settrange
{rhox} {rhoy} courbeparam

/arrowscale {1.3 dup} def
rouge
[F F 1 0 addv] ( ->) ligne
[F F 0 1 addv] ( ->) ligne

vert
F M 0 2 bddroite
noir
H M -0.2 2.5 bddroite

orange
mixte
0.6 setlinewidth
M M ThM 2 div cos ThM 2 div sin addv -5 5 bddroite

noir
[M H S] points

vert
continu
/arrowscale {2 dup} def
/arrowangle -8 def
F 1 0 addv F M 1.3 (->) tripointarc
M 1 0 addv M M F M vecteur addv 1.3 (->) tripointarc

orange
/arrowangle 4 def
M ThM 2 div cos ThM 2 div sin addv M M F M vecteur addv 2 (<-) tripointarc

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

setTimesItalic
noir
(K) K [1.5 dup] dltext
(S) S [1.5 dup] dltext
(H) H [1.5 dup] ultext
rouge
(F) F [1.5 dup] dtext

noir
<latex>
$\mathcal{D}$
</latex>
D [1.5 dup] ultexlabel

rouge
<latex>
$\vec{\imath}$
</latex>
F 0.8 -0.2 addv [1.5 dup] cctexlabel

<latex>
$\vec{\jmath}$
</latex>
F -0.2 0.7 addv [1.5 dup] cctexlabel

vert
<latex>
$\theta$
</latex>
F 1.5 0.8 addv [1.5 dup] cctexlabel

orange
<latex>
$V$
</latex>
M 1.5 1.7 addv [1.5 dup] cctexlabel