001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.actions;
003
004import static org.openstreetmap.josm.gui.help.HelpUtil.ht;
005import static org.openstreetmap.josm.tools.I18n.tr;
006
007import java.awt.event.ActionEvent;
008import java.awt.event.KeyEvent;
009import java.util.ArrayList;
010import java.util.Collection;
011import java.util.LinkedList;
012import java.util.List;
013
014import javax.swing.JOptionPane;
015
016import org.openstreetmap.josm.Main;
017import org.openstreetmap.josm.command.AddCommand;
018import org.openstreetmap.josm.command.ChangeCommand;
019import org.openstreetmap.josm.command.Command;
020import org.openstreetmap.josm.command.DeleteCommand;
021import org.openstreetmap.josm.command.SequenceCommand;
022import org.openstreetmap.josm.data.coor.EastNorth;
023import org.openstreetmap.josm.data.osm.Node;
024import org.openstreetmap.josm.data.osm.OsmPrimitive;
025import org.openstreetmap.josm.data.osm.Way;
026import org.openstreetmap.josm.gui.Notification;
027import org.openstreetmap.josm.tools.Shortcut;
028
029/**
030 * - Create a new circle from two selected nodes or a way with 2 nodes which represent the diameter of the circle.
031 * - Create a new circle from three selected nodes--or a way with 3 nodes.
032 * - Useful for roundabouts
033 *
034 * Note: If a way is selected, it is changed. If nodes are selected a new way is created.
035 *       So if you've got a way with nodes it makes a difference between running this on the way or the nodes!
036 *
037 * BTW: Someone might want to implement projection corrections for this...
038 *
039 * @author Henry Loenwind, based on much copy&Paste from other Actions.
040 * @author Sebastian Masch
041 */
042public final class CreateCircleAction extends JosmAction {
043
044    /**
045     * Constructs a new {@code CreateCircleAction}.
046     */
047    public CreateCircleAction() {
048        super(tr("Create Circle"), "createcircle", tr("Create a circle from three selected nodes."),
049            Shortcut.registerShortcut("tools:createcircle", tr("Tool: {0}", tr("Create Circle")),
050            KeyEvent.VK_O, Shortcut.SHIFT), true);
051        putValue("help", ht("/Action/CreateCircle"));
052    }
053
054    private double calcang(double xc, double yc, double x, double y) {
055        // calculate the angle from xc|yc to x|y
056        if (xc == x && yc == y)
057            return 0; // actually invalid, but we won't have this case in this context
058        double yd = Math.abs(y - yc);
059        if (yd == 0 && xc < x)
060            return 0;
061        if (yd == 0 && xc > x)
062            return Math.PI;
063        double xd = Math.abs(x - xc);
064        double a = Math.atan2(xd, yd);
065        if (y > yc) {
066            a = Math.PI - a;
067        }
068        if (x < xc) {
069            a = -a;
070        }
071        a = 1.5*Math.PI + a;
072        if (a < 0) {
073            a += 2*Math.PI;
074        }
075        if (a >= 2*Math.PI) {
076            a -= 2*Math.PI;
077        }
078        return a;
079    }
080
081    @Override
082    public void actionPerformed(ActionEvent e) {
083        if (!isEnabled())
084            return;
085
086        int numberOfNodesInCircle = Main.pref.getInteger("createcircle.nodecount", 8);
087        if (numberOfNodesInCircle < 1) {
088            numberOfNodesInCircle = 1;
089        } else if (numberOfNodesInCircle > 100) {
090            numberOfNodesInCircle = 100;
091        }
092
093        Collection<OsmPrimitive> sel = getCurrentDataSet().getSelected();
094        List<Node> nodes = new LinkedList<Node>();
095        Way existingWay = null;
096
097        for (OsmPrimitive osm : sel)
098            if (osm instanceof Node) {
099                nodes.add((Node)osm);
100            }
101
102        // special case if no single nodes are selected and exactly one way is:
103        // then use the way's nodes
104        if (nodes.isEmpty() && (sel.size() == 1)) {
105            for (OsmPrimitive osm : sel)
106                if (osm instanceof Way) {
107                    existingWay = ((Way)osm);
108                    for (Node n : ((Way)osm).getNodes())
109                    {
110                        if(!nodes.contains(n)) {
111                            nodes.add(n);
112                        }
113                    }
114                }
115        }
116
117        // now we can start doing things to OSM data
118        Collection<Command> cmds = new LinkedList<Command>();
119
120        if (nodes.size() == 2) {
121            // diameter: two single nodes needed or a way with two nodes
122
123            Node   n1 = nodes.get(0);
124            double x1 = n1.getEastNorth().east();
125            double y1 = n1.getEastNorth().north();
126            Node   n2 = nodes.get(1);
127            double x2 = n2.getEastNorth().east();
128            double y2 = n2.getEastNorth().north();
129
130            // calculate the center (xc/yc)
131            double xc = 0.5 * (x1 + x2);
132            double yc = 0.5 * (y1 + y2);
133
134            // calculate the radius (r)
135            double r = Math.sqrt(Math.pow(xc-x1,2) + Math.pow(yc-y1,2));
136
137            // find where to put the existing nodes
138            double a1 = calcang(xc, yc, x1, y1);
139            double a2 = calcang(xc, yc, x2, y2);
140            if (a1 < a2) { double at = a1; Node nt = n1; a1 = a2; n1 = n2; a2 = at; n2 = nt; }
141
142            // build a way for the circle
143            List<Node> wayToAdd = new ArrayList<Node>(numberOfNodesInCircle + 1);
144
145            for (int i = 1; i <= numberOfNodesInCircle; i++) {
146                double a = a2 + 2*Math.PI*(1.0 - i/(double)numberOfNodesInCircle); // "1-" to get it clock-wise
147
148                // insert existing nodes if they fit before this new node (999 means "already added this node")
149                if ((a1 < 999) && (a1 > a - 1E-9) && (a1 < a + 1E-9)) {
150                    wayToAdd.add(n1);
151                    a1 = 999;
152                }
153                else if ((a2 < 999) && (a2 > a - 1E-9) && (a2 < a + 1E-9)) {
154                    wayToAdd.add(n2);
155                    a2 = 999;
156                }
157                else {
158                    // get the position of the new node and insert it
159                    double x = xc + r*Math.cos(a);
160                    double y = yc + r*Math.sin(a);
161                    Node n = new Node(Main.getProjection().eastNorth2latlon(new EastNorth(x,y)));
162                    wayToAdd.add(n);
163                    cmds.add(new AddCommand(n));
164                }
165            }
166            wayToAdd.add(wayToAdd.get(0)); // close the circle
167            if (existingWay == null) {
168                Way newWay = new Way();
169                newWay.setNodes(wayToAdd);
170                cmds.add(new AddCommand(newWay));
171            } else {
172                Way newWay = new Way(existingWay);
173                newWay.setNodes(wayToAdd);
174                cmds.add(new ChangeCommand(existingWay, newWay));
175            }
176
177            // the first node may be unused/abandoned if createcircle.nodecount is odd
178            if (a1 < 999) {
179                // if it is, delete it
180                List<OsmPrimitive> parents = n1.getReferrers();
181                if (parents.isEmpty() || ((parents.size() == 1) && (parents.contains(existingWay)))) {
182                    cmds.add(new DeleteCommand(n1));
183                }
184            }
185
186        } else if (nodes.size() == 3) {
187            // triangle: three single nodes needed or a way with three nodes
188
189            // let's get some shorter names
190            Node   n1 = nodes.get(0);
191            double x1 = n1.getEastNorth().east();
192            double y1 = n1.getEastNorth().north();
193            Node   n2 = nodes.get(1);
194            double x2 = n2.getEastNorth().east();
195            double y2 = n2.getEastNorth().north();
196            Node   n3 = nodes.get(2);
197            double x3 = n3.getEastNorth().east();
198            double y3 = n3.getEastNorth().north();
199
200            // calculate the center (xc/yc)
201            double s = 0.5*((x2 - x3)*(x1 - x3) - (y2 - y3)*(y3 - y1));
202            double sUnder = (x1 - x2)*(y3 - y1) - (y2 - y1)*(x1 - x3);
203
204            if (sUnder == 0) {
205                new Notification(
206                        tr("Those nodes are not in a circle. Aborting."))
207                        .setIcon(JOptionPane.WARNING_MESSAGE)
208                        .show();
209                return;
210            }
211
212            s /= sUnder;
213
214            double xc = 0.5*(x1 + x2) + s*(y2 - y1);
215            double yc = 0.5*(y1 + y2) + s*(x1 - x2);
216
217            // calculate the radius (r)
218            double r = Math.sqrt(Math.pow(xc-x1,2) + Math.pow(yc-y1,2));
219
220            // find where to put the existing nodes
221            double a1 = calcang(xc, yc, x1, y1);
222            double a2 = calcang(xc, yc, x2, y2);
223            double a3 = calcang(xc, yc, x3, y3);
224            if (a1 < a2) { double at = a1; Node nt = n1; a1 = a2; n1 = n2; a2 = at; n2 = nt; }
225            if (a2 < a3) { double at = a2; Node nt = n2; a2 = a3; n2 = n3; a3 = at; n3 = nt; }
226            if (a1 < a2) { double at = a1; Node nt = n1; a1 = a2; n1 = n2; a2 = at; n2 = nt; }
227
228            // build a way for the circle
229            List<Node> wayToAdd = new ArrayList<Node>();
230            for (int i = 1; i <= numberOfNodesInCircle; i++) {
231                double a = 2*Math.PI*(1.0 - i/(double)numberOfNodesInCircle); // "1-" to get it clock-wise
232                // insert existing nodes if they fit before this new node (999 means "already added this node")
233                if (a1 < 999 && a1 > a) {
234                    wayToAdd.add(n1);
235                    a1 = 999;
236                }
237                if (a2 < 999 && a2 > a) {
238                    wayToAdd.add(n2);
239                    a2 = 999;
240                }
241                if (a3 < 999 && a3 > a) {
242                    wayToAdd.add(n3);
243                    a3 = 999;
244                }
245                // get the position of the new node and insert it
246                double x = xc + r*Math.cos(a);
247                double y = yc + r*Math.sin(a);
248                Node n = new Node(Main.getProjection().eastNorth2latlon(new EastNorth(x,y)));
249                wayToAdd.add(n);
250                cmds.add(new AddCommand(n));
251            }
252            wayToAdd.add(wayToAdd.get(0)); // close the circle
253            if (existingWay == null) {
254                Way newWay = new Way();
255                newWay.setNodes(wayToAdd);
256                cmds.add(new AddCommand(newWay));
257            } else {
258                Way newWay = new Way(existingWay);
259                newWay.setNodes(wayToAdd);
260                cmds.add(new ChangeCommand(existingWay, newWay));
261            }
262
263        } else {
264            new Notification(
265                    tr("Please select exactly two or three nodes or one way with exactly two or three nodes."))
266                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
267                    .setDuration(Notification.TIME_LONG)
268                    .show();
269            return;
270        }
271
272        Main.main.undoRedo.add(new SequenceCommand(tr("Create Circle"), cmds));
273        Main.map.repaint();
274    }
275
276    @Override
277    protected void updateEnabledState() {
278        if (getCurrentDataSet() == null) {
279            setEnabled(false);
280        } else {
281            updateEnabledState(getCurrentDataSet().getSelected());
282        }
283    }
284
285    @Override
286    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
287        setEnabled(selection != null && !selection.isEmpty());
288    }
289}