3 figureespace(-10u,-10u,10u,10u);
4 Initialisation(5,30,20,20);
5 draw Fonction("(cos(t)*(1+abs(t)/5),1.5*sin(t),0.2*t)",-15,15,0.1);
8 figureespace(-10u,-10u,10u,10u);
9 Initialisation(5,30,20,50);
10 outcolor:=0.5[blue,white];
11 draw Tube("(cos(t)*(1+abs(t)/5),1.5*sin(t),0.2*t)","if t>=0:(-sin(t)*(1+t/5)+cos(t)/5,1.5*cos(t),0.2) else: (-sin(t)*(1-t/5)-cos(t)/5,1.5*cos(t),0.2) fi", "if t>=0:(-cos(t)*(1+t/5)-2*sin(t)/5,-1.5*sin(t),0) else: (-cos(t)*(1-t/5)+2*sin(t)/5,-1.5*sin(t),0) fi",0.075,-10,200,0.1);