unit:=0.8;
xm:=6;
+%1
figureespace(-10u,-10u,10u,10u);
Initialisation(1000,20,45,37.5);
for k=-xm upto xm:
draw Projette((k,-xm,0))--Projette((k,xm,0));
draw Projette((-xm,k,0))--Projette((xm,k,0));
endfor;
+TraceAxes;
+Lumiere:=(0,0,0);
r:=1; q:=4;
+eclairage:=true;
arcenciel:=true;
draw Tuben("(r*((q+1)*cos(t)-cos((q+1)*t)),r*((q+1)*sin(t)-sin((q+1)*t)),0.5)","(r*(-(q+1)*sin(t)+(q+1)*sin((q+1)*t)),r*((q+1)*cos(t)-(q+1)*cos((q+1)*t)),0)",0.5,0,102,0.06283);
finespace;
+%2
figureespace(-10u,-10u,10u,10u);
Initialisation(1000,20,45,37.5);
for k=-xm upto xm:
draw Tuben("(r*((q+1)*cos(t)-cos((q+1)*t)),r*((q+1)*sin(t)-sin((q+1)*t)),0.5)","(r*(-(q+1)*sin(t)+(q+1)*sin((q+1)*t)),r*((q+1)*cos(t)-(q+1)*cos((q+1)*t)),0)",0.5,0,102,0.06283);
finespace;
+%3
figureespace(-10u,-10u,10u,10u);
Initialisation(1000,20,45,37.5);
for k=-xm upto xm: