--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+/**
+ * Represents a coordinate system.
+ */
+public interface CoordinateSystem {
+
+ /**
+ * Conversion to a reference coordinate system.
+ * @param aCoordinates Coordinates.
+ * @return Coordinates in the reference system.
+ */
+ Coordinates toReferenceSystem(Coordinates aCoordinates);
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+/**
+ * Coordinates in some 3-dimensional coordinate system.
+ */
+public class Coordinates {
+
+ private double _x1;
+ private double _x2;
+ private double _x3;
+
+ /**
+ * Constructs the coordinates.
+ * @param aX1 First coordinate.
+ * @param aX2 Second coordinate.
+ * @param aX3 Third coordinate.
+ */
+ public Coordinates(double aX1, double aX2, double aX3) {
+ _x1 = aX1;
+ _x2 = aX2;
+ _x3 = aX3;
+ }
+
+ public double getX1() {
+ return _x1;
+ }
+
+ public double getX2() {
+ return _x2;
+ }
+
+ public double getX3() {
+ return _x3;
+ }
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+import javax.xml.parsers.ParserConfigurationException;
+
+import org.dom4j.Document;
+import org.dom4j.Element;
+import org.jfree.chart.ChartFactory;
+import org.jfree.chart.ChartFrame;
+import org.jfree.chart.ChartUtilities;
+import org.jfree.chart.JFreeChart;
+import org.jfree.chart.plot.PlotOrientation;
+import org.jfree.data.xy.XYSeries;
+import org.jfree.data.xy.XYSeriesCollection;
+import org.wamblee.general.Pair;
+import org.wamblee.xml.DomUtils;
+import org.xml.sax.SAXException;
+
+/**
+ * Parses a GPX file and prints out a data file with each trackpoints distance from the start of the
+ * track and its elevation, separated by a space.
+ */
+public class GpxPlotter {
+
+ public static void main(String[] aArgs) throws ParserConfigurationException, FileNotFoundException, SAXException, IOException {
+ File file = new File(aArgs[0]);
+ Document doc = DomUtils.convert(DomUtils.read(new FileInputStream(file)));
+
+ Track track = parseTrack(doc);
+
+ List<Pair<Double,Double>> elevationProfile = computeElevationProfile(track);
+ printTrack(elevationProfile);
+ computeTotalClimb(elevationProfile);
+ plotElevationProfile(elevationProfile);
+ }
+
+ /**
+ * @param doc
+ */
+ private static Track parseTrack(Document doc) {
+ Track track = new Track();
+ Element root = doc.getRootElement().element("trk").element("trkseg");
+ for ( Iterator i =root.elementIterator("trkpt"); i.hasNext(); ) {
+ Element trkpt = (Element)i.next();
+ track.addPoint(parseTrackPoint(trkpt));
+ }
+ return track;
+ }
+
+ /**
+ * @param trkpt
+ */
+ private static TrackPoint parseTrackPoint(Element trkpt) {
+ //System.out.println(trkpt.asXML() + "|\n");
+ double latitude = new Double(trkpt.attributeValue("lat"));
+ double longitude = new Double(trkpt.attributeValue("lon"));
+ double elevation = new Double(trkpt.elementText("ele"));
+ //System.out.println(" lat = " + lat + " lon = " + lon + " ele = " + ele);
+ return new TrackPoint(latitude, longitude, elevation);
+ }
+
+ private static List<Pair<Double, Double>> computeElevationProfile(Track aTrack) {
+ List<Pair<Double,Double>> results = new ArrayList<Pair<Double,Double>>();
+ double distance = 0.0;
+ for (int i = 0; i < aTrack.size(); i++) {
+ Point point = aTrack.getPoint(i);
+ results.add(new Pair<Double,Double>(distance, point.getCoordinates().getX3()));
+ if ( i+1 < aTrack.size()) {
+ Point nextPoint = aTrack.getPoint(i+1);
+ distance += ReferenceCoordinateSystem.distance(point, nextPoint);
+ }
+ }
+ return results;
+ }
+
+ private static void printTrack(List<Pair<Double,Double>> aHeightProfile) {
+ for (Pair<Double,Double> point: aHeightProfile) {
+ System.out.println(point.getFirst() + " " + point.getSecond());
+ }
+ }
+
+ private static void computeTotalClimb(List<Pair<Double,Double>> aHeightProfile) {
+ double result = 0.0;
+
+ double lastHeight = aHeightProfile.get(0).getSecond();
+ for ( int i = 1; i < aHeightProfile.size(); i++) {
+ double height = aHeightProfile.get(i).getSecond();
+ if ( height > lastHeight) {
+ result += (height-lastHeight);
+ }
+ lastHeight = height;
+ }
+ System.out.println("Total climb: " + result);
+ }
+
+ private static void plotElevationProfile(List<Pair<Double,Double>> aHeightProfile) throws IOException {
+ XYSeries series = new XYSeries("height");
+ for (Pair<Double,Double> point: aHeightProfile) {
+ series.add(point.getFirst(), point.getSecond());
+ }
+ XYSeriesCollection dataset = new XYSeriesCollection(series);
+ JFreeChart chart = ChartFactory.createXYLineChart(
+ "Height Profile",
+ "Distance(m)",
+ "Height(m)",
+ dataset,
+ PlotOrientation.VERTICAL,
+ true,
+ true,
+ false);
+ ChartUtilities.writeChartAsPNG(new FileOutputStream("test.png"), chart, 600, 300);
+ ChartFrame frame = new ChartFrame("test", chart);
+ frame.pack();
+ frame.setVisible(true);
+ }
+
+}
+
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+/**
+ * Represents a point in some coordinate system.
+ */
+public class Point {
+
+ private Coordinates _coordinates;
+ private CoordinateSystem _system;
+
+ /**
+ * Constructs the point.
+ * @param aCoordinates Coordinates of the point in its coordinate system.
+ * @param aSystem Coordinate system.
+ */
+ public Point(Coordinates aCoordinates, CoordinateSystem aSystem) {
+ _coordinates = aCoordinates;
+ _system = aSystem;
+ }
+
+ /**
+ * Gets the coordinates in the point's coordinate system.
+ * @return Coordinates.
+ */
+ public Coordinates getCoordinates() {
+ return _coordinates;
+ }
+
+ /**
+ * Gets the coordinate system.
+ * @return Coordinate system.
+ */
+ public CoordinateSystem getCoordinateSystem() {
+ return _system;
+ }
+
+
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+/**
+ * Reference coordinate system which is the basis for defining metrics.
+ * This is a Cartesian coordinate system.
+ */
+public class ReferenceCoordinateSystem implements CoordinateSystem {
+
+ /**
+ * Constructs the coordinate system.
+ *
+ */
+ public ReferenceCoordinateSystem() {
+ // Empty
+ }
+
+ /*
+ * (non-Javadoc)
+ *
+ * @see org.wamblee.gpx.CoordinateSystem#toReferenceSystem(org.wamblee.gpx.Coordinates)
+ */
+ public Coordinates toReferenceSystem(Coordinates aCoordinates) {
+ return aCoordinates;
+ }
+
+ /*
+ * (non-Javadoc)
+ *
+ * @see org.wamblee.gpx.CoordinateSystem#distance(org.wamblee.gpx.Coordinates,
+ * org.wamblee.gpx.Coordinates)
+ */
+ private static double distance(Coordinates aC1, Coordinates aC2) {
+ return Math.sqrt(square(aC1.getX1() - aC2.getX1())
+ + square(aC1.getX2() - aC2.getX2())
+ + square(aC1.getX3() - aC2.getX3()));
+ }
+
+ private static double square(double x) {
+ return x * x;
+ }
+
+ /**
+ * Computes the distance between two points in arbitrary coordinate systems.
+ * @param aP1 First point.
+ * @param aP2 Second point.
+ * @return Distance.
+ */
+ public static double distance(Point aP1, Point aP2) {
+ return distance( aP1.getCoordinateSystem().toReferenceSystem(aP1.getCoordinates()),
+ aP2.getCoordinateSystem().toReferenceSystem(aP2.getCoordinates()));
+ }
+
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+import static java.lang.Math.PI;
+import static java.lang.Math.cos;
+import static java.lang.Math.sin;
+
+/**
+ * Represents the coordinate system for a GPS measurement identified by
+ * <ul>
+ * <li> x1: latitude in degrees </li>
+ * <li> x2: longitude in degrees </li>
+ * <li> x3: elevation in meters </li>
+ * </ul>
+ * This coordinate system models the earth as a sphere of a specific radius.
+ */
+public class SphericalCoordinateSystem implements CoordinateSystem {
+ /**
+ * Earth radius in meters.
+ */
+ private static final double EARTH_RADIUS = 6371000;
+
+
+ /* (non-Javadoc)
+ * @see org.wamblee.gpx.CoordinateSystem#toReferenceSystem(org.wamblee.gpx.Coordinates)
+ */
+ public Coordinates toReferenceSystem(Coordinates aCoordinates) {
+ double latrad = radians(aCoordinates.getX1());
+ double lonrad = radians(aCoordinates.getX2());
+ double coslat = cos(latrad);
+ double sinlat = sin(latrad);
+ double coslon = cos(lonrad);
+ double sinlon = sin(lonrad);
+
+ double trueElevation = EARTH_RADIUS + aCoordinates.getX3();
+ return new Coordinates(trueElevation*coslat*coslon,
+ trueElevation*coslat*sinlon,
+ trueElevation*sinlat);
+
+ }
+
+ private double radians(double aDegrees) {
+ return aDegrees/180.0*PI;
+ }
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Represents a GPS track.
+ */
+public class Track {
+
+ private List<TrackPoint> _points;
+
+ /**
+ * Constructs an empty track.
+ *
+ */
+ public Track() {
+ _points = new ArrayList<TrackPoint>();
+ }
+
+ /**
+ * Adds a point to a track.
+ * @param aPoint Point.
+ */
+ public void addPoint(TrackPoint aPoint) {
+ _points.add(aPoint);
+ }
+
+ /**
+ * @return Number of points in the track.
+ */
+ public int size() {
+ return _points.size();
+ }
+
+ /**
+ * Gets the point at the given inded.
+ * @param aIndex 0 <= aIndex < size()
+ * @return Point.
+ */
+ public Point getPoint(int aIndex) {
+ return _points.get(aIndex);
+ }
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+
+/**
+ * A point from a GPS track.
+ *
+ * TODO should be extended with additional information (e.g. date/time if available).
+ */
+public class TrackPoint extends Point {
+
+ /**
+ * Constructs the point.
+ * @param aLatitude Latitude in degrees.
+ * @param aLongitude Longitude in degrees.
+ * @param aElevation Elevation in metres.
+ */
+ public TrackPoint(double aLatitude, double aLongitude, double aElevation) {
+ super(new Coordinates(aLatitude, aLongitude, aElevation), new Wgs84CoordinateSystem());
+ }
+}
--- /dev/null
+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+import static java.lang.Math.PI;
+import static java.lang.Math.cos;
+import static java.lang.Math.sin;
+
+/**
+ * Represents the WGS 84 coordinate system for a GPS measurement identified by
+ * <ul>
+ * <li> x1: latitude in degrees </li>
+ * <li> x2: longitude in degrees </li>
+ * <li> x3: elevation in meters </li>
+ * </ul>
+ * WGS84 models the earth as an ellipse.
+ */
+public class Wgs84CoordinateSystem implements CoordinateSystem {
+ /*
+ * Ellipse parameters
+ */
+
+ /**
+ * The radius of the ellipse at the equator
+ */
+ private static final double A = 6378137.000;
+
+ /**
+ * The distance of the North and South poles to the center of the ellipse.
+ */
+ private static final double B = 6356752.314;
+
+
+ /* (non-Javadoc)
+ * @see org.wamblee.gpx.CoordinateSystem#toReferenceSystem(org.wamblee.gpx.Coordinates)
+ */
+ public Coordinates toReferenceSystem(Coordinates aCoordinates) {
+ double latrad = radians(aCoordinates.getX1());
+ double lonrad = radians(aCoordinates.getX2());
+ double coslat = cos(latrad);
+ double sinlat = sin(latrad);
+ double coslon = cos(lonrad);
+ double sinlon = sin(lonrad);
+
+ double r = A*B/Math.sqrt(B*B*coslat*coslat + A*A*sinlat*sinlat) + aCoordinates.getX3();
+
+ return new Coordinates(r*coslat*coslon,
+ r*coslat*sinlon,
+ r*sinlat);
+
+ }
+
+ private double radians(double aDegrees) {
+ return aDegrees/180.0*PI;
+ }
+}
git://wamblee.org / utils / commitdiff