prologues := 3;
outputtemplate := "%j/%j-%c.svg";
outputformat := "svg";
verbatimtex
%&latex
\documentclass{article}
\usepackage[charter]{mathdesign}
\usepackage{amsmath}
\usepackage[utf8]{inputenc}
\usepackage[frenchb]{babel}
\begin{document}
etex
u:=0.7cm;
a:=3u;
path cercle, droite, cissoide;
pair M,O;
M:=(-a,0);
O:=(0,0);
droite:=(2a,-8u)--(2a,8u);
cercle:= fullcircle scaled 2a shifted M;
for i:=0 upto 400:
beginfig(i);
path drtour,demid;
pair M,P,Hb,H;
drawarrow (-8u,0)--(8u,0);
drawarrow (0,-8u)--(0,8u);
H:=(2a,i/10*u-20u);
Hb:=(-xpart H, -ypart H);
demid:= 0.01[O,Hb]--2[O,Hb];
P:=demid intersectionpoint cercle;
M:=.5[H,P];
if i=0:
cissoide:=M;
else:
cissoide:=cissoide--M;
fi;
draw cercle withpen pencircle scaled 0.8pt withcolor blue;
draw droite withpen pencircle scaled 0.8pt withcolor blue;
draw H--P dashed evenly withpen pencircle scaled 0.8pt withcolor green;
draw cissoide withpen pencircle scaled 1pt withcolor red;
dotlabel.urt(btex $M$ etex,M);
dotlabel.rt(btex $H$ etex,H);
dotlabel.llft(btex $P$ etex,P);
dotlabel.lrt(btex $O$ etex, O);
label.bot(btex $x$ etex, (7.6u,0));
label.rt(btex $y$ etex, (0,7.6u));
label.bot(btex $2a$ etex, (-a,0));
label.bot(btex $2a$ etex, (a,0));
label.urt(btex $\mathcal{C}$ etex, (-0.5a,a));
label.rt(btex $\Delta$ etex, (2a,-7.5u));
label.bot(btex \textit{Cissoïde droite} : \(\left\{\begin{array}{l} x=\dfrac{2at^2}{1+t^2}\\y=\dfrac{2at^3}{1+t^2} \end{array}\right.\) etex,(-4u,7u));
clip currentpicture to (-8u,-8u)--(-8u,8u)--(8u,8u)--(8u,-8u)--cycle;
endfig;
endfor;
end.