// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.tools;
import java.awt.geom.Area;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Collection;
import org.openstreetmap.josm.data.coor.LatLon;
import org.openstreetmap.josm.data.osm.BBox;
import org.openstreetmap.josm.data.osm.DataSet;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.io.CachedFile;
import org.openstreetmap.josm.io.IllegalDataException;
import org.openstreetmap.josm.io.OsmReader;
import org.openstreetmap.josm.tools.GeoPropertyIndex.GeoProperty;
import org.openstreetmap.josm.tools.Geometry.PolygonIntersection;
/**
* Look up, if there is right- or left-hand traffic at a certain place.
*/
public class RightAndLefthandTraffic {
private static class RLTrafficGeoProperty implements GeoProperty<Boolean> {
@Override
public Boolean get(LatLon ll) {
for (Area a : leftHandTrafficPolygons) {
if (a.contains(ll.lon(), ll.lat()))
return true;
}
return false;
}
@Override
public Boolean get(BBox box) {
Area abox = new Area(box.toRectangle());
for (Area a : leftHandTrafficPolygons) {
PolygonIntersection is = Geometry.polygonIntersection(abox, a, 1e-10 /* using deg and not meters */);
if (is == PolygonIntersection.FIRST_INSIDE_SECOND)
return true;
if (is != PolygonIntersection.OUTSIDE)
return null;
}
return false;
}
}
private static Collection<Area> leftHandTrafficPolygons;
private static GeoPropertyIndex<Boolean> rlCache;
/**
* Check if there is right-hand traffic at a certain location.
*
* TODO: Synchronization can be refined inside the {@link GeoPropertyIndex}
* as most look-ups are read-only.
* @param ll the coordinates of the point
* @return true if there is right-hand traffic, false if there is left-hand traffic
*/
public static synchronized boolean isRightHandTraffic(LatLon ll) {
if (leftHandTrafficPolygons == null) {
initialize();
}
return !rlCache.get(ll);
}
private static void initialize() {
leftHandTrafficPolygons = new ArrayList<>();
try (InputStream is = new CachedFile("resource://data/left-right-hand-traffic.osm").getInputStream()) {
DataSet data = OsmReader.parseDataSet(is, null);
for (Way w : data.getWays()) {
leftHandTrafficPolygons.add(Geometry.getAreaLatLon(w.getNodes()));
}
} catch (IOException | IllegalDataException ex) {
throw new RuntimeException(ex);
}
rlCache = new GeoPropertyIndex<Boolean>(new RLTrafficGeoProperty(), 24);
}
}