// License: GPL. For details, see LICENSE file.
package cadastre_fr;
import java.util.ArrayList;
import java.util.List;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.data.projection.Ellipsoid;
/**
* Imported from plugin UtilsPlugin
* @author
*
*/
public class SimplifyWay {
public void simplifyWay(Way w/*, DataSet dataSet*/, double threshold) {
Way wnew = new Way(w);
simplifyWayRange(wnew, 0, wnew.getNodesCount() - 1, threshold);
w.setNodes(wnew.getNodes());
}
public void simplifyWayRange(Way wnew, int from, int to, double thr) {
if (to - from >= 2) {
ArrayList<Node> ns = new ArrayList<>();
simplifyWayRange(wnew, from, to, ns, thr);
List<Node> nodes = wnew.getNodes();
for (int j = to - 1; j > from; j--) {
nodes.remove(j);
}
nodes.addAll(from+1, ns);
wnew.setNodes(nodes);
}
}
/**
* Takes an interval [from,to] and adds nodes from (from,to) to ns.
* (from and to are indices of wnew.nodes.)
*/
public void simplifyWayRange(Way wnew, int from, int to, ArrayList<Node> ns, double thr) {
Node fromN = wnew.getNode(from), toN = wnew.getNode(to);
int imax = -1;
double xtemax = 0;
for (int i = from + 1; i < to; i++) {
Node n = wnew.getNode(i);
double xte = Math.abs(Ellipsoid.WGS84.a
* xtd(fromN.getCoor().lat() * Math.PI / 180, fromN.getCoor().lon() * Math.PI / 180, toN.getCoor().lat() * Math.PI
/ 180, toN.getCoor().lon() * Math.PI / 180, n.getCoor().lat() * Math.PI / 180, n.getCoor().lon() * Math.PI
/ 180));
if (xte > xtemax) {
xtemax = xte;
imax = i;
}
}
if (imax != -1 && xtemax >= thr) {
simplifyWayRange(wnew, from, imax, ns, thr);
ns.add(wnew.getNode(imax));
simplifyWayRange(wnew, imax, to, ns, thr);
}
}
/* From Aviaton Formulary v1.3
* http://williams.best.vwh.net/avform.htm
*/
public static double dist(double lat1, double lon1, double lat2, double lon2) {
return 2 * Math.asin(Math.sqrt(Math.pow(Math.sin((lat1 - lat2) / 2), 2) + Math.cos(lat1) * Math.cos(lat2)
* Math.pow(Math.sin((lon1 - lon2) / 2), 2)));
}
public static double course(double lat1, double lon1, double lat2, double lon2) {
return Math.atan2(Math.sin(lon1 - lon2) * Math.cos(lat2), Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1)
* Math.cos(lat2) * Math.cos(lon1 - lon2))
% (2 * Math.PI);
}
public static double xtd(double lat1, double lon1, double lat2, double lon2, double lat3, double lon3) {
double dist_AD = dist(lat1, lon1, lat3, lon3);
double crs_AD = course(lat1, lon1, lat3, lon3);
double crs_AB = course(lat1, lon1, lat2, lon2);
return Math.asin(Math.sin(dist_AD) * Math.sin(crs_AD - crs_AB));
}
}