[aksios]

Ух уж эта геометрия.

function radians(degrees) {
	return (Math.PI/180)*degrees;
}
theta = 45;
//радиус:
r=100;
d = r/Math.cos(radians(.5*theta));
this.lineStyle(1, 0x000000, 100);
this.moveTo(r, 0);
for (k=(theta/2); k<361; k=k+theta) {
	xControl = d*Math.cos(radians(k));
	yControl = d*Math.sin(radians(k));
	xAnchor = r*Math.cos(radians(k+(theta/2)));
	yAnchor = r*Math.sin(radians(k+(theta/2)));
	this.curveTo(xControl, yControl, xAnchor, yAnchor);
}
//координаты центра:
this._x = 200
this._y = 200