@Test
public void testTileCodeComparatorSymmetry() {

	List<TileCode> list = createTileCodes(0, 0, 3, 3); 
	TileCodeComparator comp = new TileCodeComparator(1, 1);
	for (TileCode code1 : list) {
		for (TileCode code2 : list) {
			int left = comp.compare(code1, code2);
			int right = - comp.compare(code2, code1);
			if (left != right) {
				System.out.println(code1 + " " + code2);
			}
			Assert.assertEquals(left, right);
		}
	}
}