public static double MapScale(final double latitude, final int levelOfDetail, final int screenDpi) {
        return GroundResolution(latitude, levelOfDetail) * screenDpi / 0.0254;
    }
@Test
    public void test_groundMapScale() {
        final double delta = 1e-2;

        for (int zoomLevel = mMinZoomLevel; zoomLevel <= mMaxZoomLevel; zoomLevel++) {
            Assert.assertEquals(591658710.9 / (1 << zoomLevel), TileSystem.MapScale(0, zoomLevel, 96), delta);
        }
    }