//License: GPL. Copyright 2007 by Immanuel Scholz and others
package org.openstreetmap.josm.actions;
import static org.openstreetmap.josm.tools.I18n.tr;
import static org.openstreetmap.josm.gui.help.HelpUtil.ht;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.math.BigDecimal;
import java.math.MathContext;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
import javax.swing.JOptionPane;
import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.command.Command;
import org.openstreetmap.josm.command.MoveCommand;
import org.openstreetmap.josm.command.SequenceCommand;
import org.openstreetmap.josm.data.coor.EastNorth;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.tools.Shortcut;
/**
* Aligns all selected nodes within a circle. (Useful for roundabouts)
*
* @author Matthew Newton
* @author Petr Dlouhý
* @author Teemu Koskinen
*/
public final class AlignInCircleAction extends JosmAction {
public AlignInCircleAction() {
super(tr("Align Nodes in Circle"), "aligncircle", tr("Move the selected nodes into a circle."),
Shortcut.registerShortcut("tools:aligncircle", tr("Tool: {0}", tr("Align Nodes in Circle")),
KeyEvent.VK_O, Shortcut.GROUP_EDIT), true);
putValue("help", ht("/Action/AlignInCircle"));
}
public double distance(EastNorth n, EastNorth m) {
double easd, nord;
easd = n.east() - m.east();
nord = n.north() - m.north();
return Math.sqrt(easd * easd + nord * nord);
}
public class PolarCoor {
double radius;
double angle;
EastNorth origin = new EastNorth(0, 0);
double azimuth = 0;
PolarCoor(double radius, double angle) {
this(radius, angle, new EastNorth(0, 0), 0);
}
PolarCoor(double radius, double angle, EastNorth origin, double azimuth) {
this.radius = radius;
this.angle = angle;
this.origin = origin;
this.azimuth = azimuth;
}
PolarCoor(EastNorth en) {
this(en, new EastNorth(0, 0), 0);
}
PolarCoor(EastNorth en, EastNorth origin, double azimuth) {
radius = distance(en, origin);
angle = Math.atan2(en.north() - origin.north(), en.east() - origin.east());
this.origin = origin;
this.azimuth = azimuth;
}
public EastNorth toEastNorth() {
return new EastNorth(radius * Math.cos(angle - azimuth) + origin.east(), radius * Math.sin(angle - azimuth)
+ origin.north());
}
}
public void actionPerformed(ActionEvent e) {
if (!isEnabled())
return;
Collection<OsmPrimitive> sel = getCurrentDataSet().getSelected();
List<Node> nodes = new LinkedList<Node>();
List<Way> ways = new LinkedList<Way>();
EastNorth center = null;
double radius = 0;
boolean regular = false;
for (OsmPrimitive osm : sel) {
if (osm instanceof Node) {
nodes.add((Node) osm);
} else if (osm instanceof Way) {
ways.add((Way) osm);
}
}
// special case if no single nodes are selected and exactly one way is:
// then use the way's nodes
if ((nodes.size() <= 2) && (ways.size() == 1)) {
Way way = ways.get(0);
// some more special combinations:
// When is selected node that is part of the way, then make a regular polygon, selected
// node doesn't move.
// I haven't got better idea, how to activate that function.
//
// When one way and one node is selected, set center to position of that node.
// When one more node, part of the way, is selected, set the radius equal to the
// distance between two nodes.
if (nodes.size() > 0) {
if (nodes.size() == 1 && way.containsNode(nodes.get(0))) {
regular = true;
} else {
center = nodes.get(way.containsNode(nodes.get(0)) ? 1 : 0).getEastNorth();
if (nodes.size() == 2) {
radius = distance(nodes.get(0).getEastNorth(), nodes.get(1).getEastNorth());
}
}
nodes = new LinkedList<Node>();
}
for (Node n : way.getNodes()) {
if (!nodes.contains(n)) {
nodes.add(n);
}
}
}
if (nodes.size() < 4) {
JOptionPane.showMessageDialog(
Main.parent,
tr("Please select at least four nodes."),
tr("Information"),
JOptionPane.INFORMATION_MESSAGE
);
return;
}
// Reorder the nodes if they didn't come from a single way
if (ways.size() != 1) {
// First calculate the average point
BigDecimal east = new BigDecimal(0);
BigDecimal north = new BigDecimal(0);
for (Node n : nodes) {
BigDecimal x = new BigDecimal(n.getEastNorth().east());
BigDecimal y = new BigDecimal(n.getEastNorth().north());
east = east.add(x, MathContext.DECIMAL128);
north = north.add(y, MathContext.DECIMAL128);
}
BigDecimal nodesSize = new BigDecimal(nodes.size());
east = east.divide(nodesSize, MathContext.DECIMAL128);
north = north.divide(nodesSize, MathContext.DECIMAL128);
EastNorth average = new EastNorth(east.doubleValue(), north.doubleValue());
List<Node> newNodes = new LinkedList<Node>();
// Then reorder them based on heading from the average point
while (!nodes.isEmpty()) {
double maxHeading = -1.0;
Node maxNode = null;
for (Node n : nodes) {
double heading = average.heading(n.getEastNorth());
if (heading > maxHeading) {
maxHeading = heading;
maxNode = n;
}
}
newNodes.add(maxNode);
nodes.remove(maxNode);
}
nodes = newNodes;
}
if (center == null) {
// Compute the centroid of nodes
BigDecimal area = new BigDecimal(0);
BigDecimal north = new BigDecimal(0);
BigDecimal east = new BigDecimal(0);
// See http://en.wikipedia.org/w/index.php?title=Centroid&oldid=294224857#Centroid_of_polygon for the equation used here
for (int i = 0; i < nodes.size(); i++) {
EastNorth n0 = nodes.get(i).getEastNorth();
EastNorth n1 = nodes.get((i+1) % nodes.size()).getEastNorth();
BigDecimal x0 = new BigDecimal(n0.east());
BigDecimal y0 = new BigDecimal(n0.north());
BigDecimal x1 = new BigDecimal(n1.east());
BigDecimal y1 = new BigDecimal(n1.north());
BigDecimal k = x0.multiply(y1, MathContext.DECIMAL128).subtract(y0.multiply(x1, MathContext.DECIMAL128));
area = area.add(k, MathContext.DECIMAL128);
east = east.add(k.multiply(x0.add(x1, MathContext.DECIMAL128), MathContext.DECIMAL128));
north = north.add(k.multiply(y0.add(y1, MathContext.DECIMAL128), MathContext.DECIMAL128));
}
BigDecimal d = new BigDecimal(3, MathContext.DECIMAL128); // 1/2 * 6 = 3
area = area.multiply(d, MathContext.DECIMAL128);
north = north.divide(area, MathContext.DECIMAL128);
east = east.divide(area, MathContext.DECIMAL128);
center = new EastNorth(east.doubleValue(), north.doubleValue());
}
// Node "center" now is central to all selected nodes.
// Now calculate the average distance to each node from the
// centre. This method is ok as long as distances are short
// relative to the distance from the N or S poles.
if (radius == 0) {
for (Node n : nodes) {
radius += distance(center, n.getEastNorth());
}
radius = radius / nodes.size();
}
Collection<Command> cmds = new LinkedList<Command>();
PolarCoor pc;
if (regular) { // Make a regular polygon
double angle = Math.PI * 2 / nodes.size();
pc = new PolarCoor(nodes.get(0).getEastNorth(), center, 0);
if (pc.angle > (new PolarCoor(nodes.get(1).getEastNorth(), center, 0).angle)) {
angle *= -1;
}
pc.radius = radius;
for (Node n : nodes) {
EastNorth no = pc.toEastNorth();
cmds.add(new MoveCommand(n, no.east() - n.getEastNorth().east(), no.north() - n.getEastNorth().north()));
pc.angle += angle;
}
} else { // Move each node to that distance from the centre.
for (Node n : nodes) {
pc = new PolarCoor(n.getEastNorth(), center, 0);
pc.radius = radius;
EastNorth no = pc.toEastNorth();
cmds.add(new MoveCommand(n, no.east() - n.getEastNorth().east(), no.north() - n.getEastNorth().north()));
}
}
Main.main.undoRedo.add(new SequenceCommand(tr("Align Nodes in Circle"), cmds));
Main.map.repaint();
}
@Override
protected void updateEnabledState() {
setEnabled(getCurrentDataSet() != null && !getCurrentDataSet().getSelected().isEmpty());
}
@Override
protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
setEnabled(selection != null && !selection.isEmpty());
}
}