EGM2008: added undulation data and bilinear computation.

Includes data structure for caching.

Part of #224.
This commit is contained in:
Dennis Guse
2021-03-28 18:53:37 +02:00
parent b395c19832
commit fa50db08c3
3 changed files with 38419 additions and 0 deletions
@@ -0,0 +1,229 @@
package de.dennisguse.opentracks.util;
import android.content.Context;
import androidx.test.core.app.ApplicationProvider;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import java.io.DataInputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.time.Instant;
import de.dennisguse.opentracks.content.data.TrackPoint;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;
@RunWith(JUnit4.class)
public class EGM2008UtilsTest {
private static final double MAX_BILINEAR_ERROR = 0.478;
private final Context context = ApplicationProvider.getApplicationContext();
@Test
public void fileVerification() throws IOException {
// given
int expectedLength = 18671444;
int expectedHeaderLength = 404;
String expectedHeader = "P5\n" +
"# Geoid file in PGM format for the GeographicLib::Geoid class\n" +
"# Description WGS84 EGM2008, 5-minute grid\n" +
"# URL http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm2008\n" +
"# DateTime 2009-08-29 18:45:00\n" +
"# MaxBilinearError 0.478\n" +
"# RMSBilinearError 0.012\n" +
"# MaxCubicError 0.294\n" +
"# RMSCubicError 0.005\n" +
"# Offset -108\n" +
"# Scale 0.003\n" +
"# Origin 90N 0E\n" +
"# AREA_OR_POINT Point\n" +
"# Vertical_Datum WGS84\n" +
"4320 2161\n" +
"65535" +
"\n";
// when
try (InputStream inputStream = context.getResources().openRawResource(EGM2008Utils.EGM2008_5_DATA)) {
assertEquals(expectedLength, inputStream.available());
InputStreamReader reader = new InputStreamReader(inputStream, StandardCharsets.US_ASCII);
char[] data = new char[expectedHeaderLength];
int length = reader.read(data);
// then
assertEquals(expectedHeaderLength, length);
assertEquals(expectedHeader, new String(data));
}
}
@Test
public void data_Northpole() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(90);
trackPoint.setLongitude(0.1);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(-14.8980, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void data_Southpole() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(-90);
trackPoint.setLongitude(0);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(30.15, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void data_Southpole2() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(-90);
trackPoint.setLongitude(180);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(30.15, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void data_Southpole3() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(-90);
trackPoint.setLongitude(-180);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(30.15, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void data_0() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(0);
trackPoint.setLongitude(0);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(-17.2260, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void data_Berlin() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(52.530644);
trackPoint.setLongitude(13.383068);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(-39.4865, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void data_Berlin_Caching() throws IOException {
// given
TrackPoint trackPoint1 = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint1.setLatitude(52.530644);
trackPoint1.setLongitude(13.383068);
trackPoint1.setAltitude(0);
TrackPoint trackPoint2 = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint2.setLatitude(52.530000);
trackPoint2.setLongitude(13.380000);
trackPoint2.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint1.getLocation());
// then
assertNotEquals(altitude_egm2008.correctAltitude(trackPoint1.getLocation()), altitude_egm2008.correctAltitude(trackPoint2.getLocation()), 0.0001);
}
@Test
public void data_MaxUndulation() throws IOException {
// given
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(-8.417);
trackPoint.setLongitude(147.367);
trackPoint.setAltitude(0);
// when
EGM2008Utils.EGM2008Correction altitude_egm2008 = EGM2008Utils.createEGM2008Correction(context, trackPoint.getLocation());
// then
assertEquals(-85.824, altitude_egm2008.correctAltitude(trackPoint.getLocation()), MAX_BILINEAR_ERROR);
}
@Test
public void getIndices() {
TrackPoint trackPoint = new TrackPoint(TrackPoint.Type.TRACKPOINT, Instant.ofEpochMilli(0));
trackPoint.setLatitude(90);
trackPoint.setLongitude(0);
assertEquals(new EGM2008Utils.Indices(0, 0), EGM2008Utils.getIndices(trackPoint.getLocation()));
trackPoint.setLatitude(0);
trackPoint.setLongitude(0);
assertEquals(new EGM2008Utils.Indices(1080, 0), EGM2008Utils.getIndices(trackPoint.getLocation()));
trackPoint.setLatitude(-90);
trackPoint.setLongitude(180);
assertEquals(new EGM2008Utils.Indices(2160, 4320 / 2), EGM2008Utils.getIndices(trackPoint.getLocation()));
trackPoint.setLatitude(-90);
trackPoint.setLongitude(-180);
assertEquals(new EGM2008Utils.Indices(2160, 0), EGM2008Utils.getIndices(trackPoint.getLocation()));
}
@Test
public void getUndulationRaw_ok() throws IOException {
try (DataInputStream dataInputStream = new DataInputStream(context.getResources().openRawResource(EGM2008Utils.EGM2008_5_DATA))) {
assertEquals(40966, EGM2008Utils.getUndulationRaw(dataInputStream, new EGM2008Utils.Indices(0, 0)));
assertEquals(41742, EGM2008Utils.getUndulationRaw(dataInputStream, new EGM2008Utils.Indices(1081, 0)));
assertEquals(25950, EGM2008Utils.getUndulationRaw(dataInputStream, new EGM2008Utils.Indices(2160, 4319)));
}
}
@Test(expected = EOFException.class)
public void getUndulationRaw_error() throws IOException {
try (DataInputStream dataInputStream = new DataInputStream(context.getResources().openRawResource(EGM2008Utils.EGM2008_5_DATA))) {
assertEquals(0, EGM2008Utils.getUndulationRaw(dataInputStream, new EGM2008Utils.Indices(2161, 4320)), 0.01);
}
}
}