@Test
  public void testGetTileFromCoordinateUSA() {

    NASAZoomLevel zoomLevel = sourceUSA.getZoomLevel(3);
    WMTTileFactory tileFactory = sourceUSA.getTileFactory();

    NASATile tile = (NASATile) tileFactory.getTileFromCoordinate(50, -125, zoomLevel, sourceUSA);
    assertEquals("Continental US Elevation_3_0_0", tile.getId());

    NASATile tile2 = (NASATile) tileFactory.getTileFromCoordinate(39, -125, zoomLevel, sourceUSA);
    assertEquals("Continental US Elevation_3_0_1", tile2.getId());

    NASATile tile3 = (NASATile) tileFactory.getTileFromCoordinate(39, -114, zoomLevel, sourceUSA);
    assertEquals("Continental US Elevation_3_1_1", tile3.getId());
  }
  @Test
  public void testGetTileFromCoordinate() {

    NASAZoomLevel zoomLevel = source.getZoomLevel(0);
    WMTTileFactory tileFactory = source.getTileFactory();

    NASATile tile = (NASATile) tileFactory.getTileFromCoordinate(90, -180, zoomLevel, source);
    assertEquals("Global Mosaic, pan sharpened visual_0_0_0", tile.getId());

    NASATile tile2 = (NASATile) tileFactory.getTileFromCoordinate(-90, -180, zoomLevel, source);
    assertEquals("Global Mosaic, pan sharpened visual_0_0_2", tile2.getId());

    NASATile tile3 = (NASATile) tileFactory.getTileFromCoordinate(-90, -115, zoomLevel, source);
    assertEquals("Global Mosaic, pan sharpened visual_0_1_2", tile3.getId());
  }