@Test
public void testGetLevel() {

    HeightFilter filter = new HeightFilter(32, 10, 20, true);
    for (int z = 0; z < 32; z++) {
        System.out.printf("Level %3d: %2d%n", z, filter.getLevel(0, 0, z, 15));
    }
    filter = new HeightFilter(32, 0, 31, false);
    for (int z = 0; z < 32; z++) {
        System.out.printf("Level %3d: %2d%n", z, filter.getLevel(0, 0, z, 15));
    }
    filter = new HeightFilter(32, 10, 20, false);
    for (int z = 0; z < 32; z++) {
        System.out.printf("Level %3d: %2d%n", z, filter.getLevel(0, 0, z, 15));
    }
}