o=Point(0,0);SetHide(o,true);
N=20;
for (i=0; i<N; i++){
	t=2*Math.PI*i/N;
	a=Point(Math.cos(t),Math.sin(t));SetHide(a,true);
	b=Point(Math.SQRT2*Math.cos(t+Math.PI/4),Math.SQRT2*Math.sin(t+Math.PI/4));SetHide(b,true);
	c=Point(-Math.sin(t),Math.cos(t));SetHide(c,true);
	t=Polygon("",o+","+a+","+b+","+c);
}