private void checkTriangle(Triangle triangle) {
        Vector3f center = triangle.getCenter();
        Vector3f normal = triangle.getNormal();
        assert center.equals(new Vector3f(1f, 0f, 1f));
        assert normal.equals(new Vector3f(0f, -1f, 0f));
    }
Check center and normal after modification.
jme3-core/src/test/java/com/jme3/math/TestIssue957.java