    @Test
    public void circularAddTest2() {


        vd.clear();

        List<Point2d> polygon = new ArrayList<Point2d>();

        polygon.add(new Point2d(50, 50));
        polygon.add(new Point2d(150, 50));
        polygon.add(new Point2d(150, 100));
        polygon.add(new Point2d(50, 100));

        List<Point2d> expected = new ArrayList<Point2d>();
        expected.add(p(75.000000, 75.000000));
        expected.add(p(125.000000, 75.000000));
        expected.addAll(polygon);

        SkeletonOutput sk = Skeleton.skeleton(polygon);

        visualizeResults(polygon, sk);

        validate(polygon, sk);

        assertExpectedPoints(expected, getFacePoints(sk));
    }