@Test public void testCenter() { final Triangle tri1 = new Triangle(Vector3.ZERO, Vector3.UNIT_Y, Vector3.UNIT_X, 0); assertEquals(new Vector3(1 / 3., 1 / 3., 0), tri1.getCenter()); // dirty assertEquals(new Vector3(1 / 3., 1 / 3., 0), tri1.getCenter()); // clean tri1.setA(Vector3.ONE); assertEquals(new Vector3(2 / 3., 2 / 3., 1 / 3.), tri1.getCenter()); // dirty, but with existing center }