@Test
public void testAngleBetween4() {

    final Vector3f target = new Vector3f(0.0f, -1.0f, 0.0f);
    final Vector3f otherVector = new Vector3f(1.0f, 0.0f, 0.0f);
    assertEquals(1.57f, target.angleBetween(otherVector), 0.01f);
}