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.Collections;
012import java.util.HashSet;
013import java.util.LinkedList;
014import java.util.List;
015import java.util.Set;
016
017import javax.swing.JOptionPane;
018
019import org.openstreetmap.josm.Main;
020import org.openstreetmap.josm.command.Command;
021import org.openstreetmap.josm.command.MoveCommand;
022import org.openstreetmap.josm.command.SequenceCommand;
023import org.openstreetmap.josm.data.coor.EastNorth;
024import org.openstreetmap.josm.data.osm.Node;
025import org.openstreetmap.josm.data.osm.OsmPrimitive;
026import org.openstreetmap.josm.data.osm.Way;
027import org.openstreetmap.josm.gui.Notification;
028import org.openstreetmap.josm.tools.Geometry;
029import org.openstreetmap.josm.tools.Shortcut;
030
031/**
032 * Aligns all selected nodes within a circle. (Useful for roundabouts)
033 *
034 * @author Matthew Newton
035 * @author Petr DlouhĂ˝
036 * @author Teemu Koskinen
037 * @author Alain Delplanque
038 *
039 * @since 146
040 */
041public final class AlignInCircleAction extends JosmAction {
042
043    /**
044     * Constructs a new {@code AlignInCircleAction}.
045     */
046    public AlignInCircleAction() {
047        super(tr("Align Nodes in Circle"), "aligncircle", tr("Move the selected nodes into a circle."),
048                Shortcut.registerShortcut("tools:aligncircle", tr("Tool: {0}", tr("Align Nodes in Circle")),
049                        KeyEvent.VK_O, Shortcut.DIRECT), true);
050        putValue("help", ht("/Action/AlignInCircle"));
051    }
052
053    private static double distance(EastNorth n, EastNorth m) {
054        double easd, nord;
055        easd = n.east() - m.east();
056        nord = n.north() - m.north();
057        return Math.sqrt(easd * easd + nord * nord);
058    }
059
060    public static class PolarCoor {
061        private double radius;
062        private double angle;
063        private EastNorth origin = new EastNorth(0, 0);
064        private double azimuth;
065
066        PolarCoor(double radius, double angle) {
067            this(radius, angle, new EastNorth(0, 0), 0);
068        }
069
070        PolarCoor(double radius, double angle, EastNorth origin, double azimuth) {
071            this.radius = radius;
072            this.angle = angle;
073            this.origin = origin;
074            this.azimuth = azimuth;
075        }
076
077        PolarCoor(EastNorth en) {
078            this(en, new EastNorth(0, 0), 0);
079        }
080
081        PolarCoor(EastNorth en, EastNorth origin, double azimuth) {
082            radius = distance(en, origin);
083            angle = Math.atan2(en.north() - origin.north(), en.east() - origin.east());
084            this.origin = origin;
085            this.azimuth = azimuth;
086        }
087
088        public EastNorth toEastNorth() {
089            return new EastNorth(radius * Math.cos(angle - azimuth) + origin.east(), radius * Math.sin(angle - azimuth)
090                    + origin.north());
091        }
092
093        /**
094         * Create a MoveCommand to move a node to this PolarCoor.
095         * @param n Node to move
096         * @return new MoveCommand
097         */
098        public MoveCommand createMoveCommand(Node n) {
099            EastNorth en = toEastNorth();
100            return new MoveCommand(n, en.east() - n.getEastNorth().east(), en.north() - n.getEastNorth().north());
101        }
102    }
103
104
105    /**
106     * Perform AlignInCircle action.
107     *
108     * A fixed node is a node for which it is forbidden to change the angle relative to center of the circle.
109     * All other nodes are uniformly distributed.
110     *
111     * Case 1: One unclosed way.
112     * --> allow action, and align selected way nodes
113     * If nodes contained by this way are selected, there are fix.
114     * If nodes outside from the way are selected there are ignored.
115     *
116     * Case 2: One or more ways are selected and can be joined into a polygon
117     * --> allow action, and align selected ways nodes
118     * If 1 node outside of way is selected, it became center
119     * If 1 node outside and 1 node inside are selected there define center and radius
120     * If no outside node and 2 inside nodes are selected those 2 nodes define diameter
121     * In all other cases outside nodes are ignored
122     * In all cases, selected nodes are fix, nodes with more than one referrers are fix
123     * (first referrer is the selected way)
124     *
125     * Case 3: Only nodes are selected
126     * --> Align these nodes, all are fix
127     */
128    @Override
129    public void actionPerformed(ActionEvent e) {
130        if (!isEnabled())
131            return;
132
133        Collection<OsmPrimitive> sel = getCurrentDataSet().getSelected();
134        List<Node> nodes = new LinkedList<>();
135        // fixNodes: All nodes for which the angle relative to center should not be modified
136        Set<Node> fixNodes = new HashSet<>();
137        List<Way> ways = new LinkedList<>();
138        EastNorth center = null;
139        double radius = 0;
140
141        for (OsmPrimitive osm : sel) {
142            if (osm instanceof Node) {
143                nodes.add((Node) osm);
144            } else if (osm instanceof Way) {
145                ways.add((Way) osm);
146            }
147        }
148
149        if (ways.size() == 1 && !ways.get(0).isClosed()) {
150            // Case 1
151            Way w = ways.get(0);
152            fixNodes.add(w.firstNode());
153            fixNodes.add(w.lastNode());
154            fixNodes.addAll(nodes);
155            fixNodes.addAll(collectNodesWithExternReferers(ways));
156            // Temporary closed way used to reorder nodes
157            Way closedWay = new Way(w);
158            closedWay.addNode(w.firstNode());
159            List<Way> usedWays = new ArrayList<>(1);
160            usedWays.add(closedWay);
161            nodes = collectNodesAnticlockwise(usedWays);
162        } else if (!ways.isEmpty() && checkWaysArePolygon(ways)) {
163            // Case 2
164            List<Node> inside = new ArrayList<>();
165            List<Node> outside = new ArrayList<>();
166
167            for (Node n: nodes) {
168                boolean isInside = false;
169                for (Way w: ways) {
170                    if (w.getNodes().contains(n)) {
171                        isInside = true;
172                        break;
173                    }
174                }
175                if (isInside)
176                    inside.add(n);
177                else
178                    outside.add(n);
179            }
180
181            if (outside.size() == 1 && inside.isEmpty()) {
182                center = outside.get(0).getEastNorth();
183            } else if (outside.size() == 1 && inside.size() == 1) {
184                center = outside.get(0).getEastNorth();
185                radius = distance(center, inside.get(0).getEastNorth());
186            } else if (inside.size() == 2 && outside.isEmpty()) {
187                // 2 nodes inside, define diameter
188                EastNorth en0 = inside.get(0).getEastNorth();
189                EastNorth en1 = inside.get(1).getEastNorth();
190                center = new EastNorth((en0.east() + en1.east()) / 2, (en0.north() + en1.north()) / 2);
191                radius = distance(en0, en1) / 2;
192            }
193
194            fixNodes.addAll(inside);
195            fixNodes.addAll(collectNodesWithExternReferers(ways));
196            nodes = collectNodesAnticlockwise(ways);
197            if (nodes.size() < 4) {
198                new Notification(
199                        tr("Not enough nodes in selected ways."))
200                .setIcon(JOptionPane.INFORMATION_MESSAGE)
201                .setDuration(Notification.TIME_SHORT)
202                .show();
203                return;
204            }
205        } else if (ways.isEmpty() && nodes.size() > 3) {
206            // Case 3
207            fixNodes.addAll(nodes);
208            // No need to reorder nodes since all are fix
209        } else {
210            // Invalid action
211            new Notification(
212                    tr("Please select at least four nodes."))
213                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
214                    .setDuration(Notification.TIME_SHORT)
215                    .show();
216            return;
217        }
218
219        if (center == null) {
220            // Compute the center of nodes
221            center = Geometry.getCenter(nodes);
222            if (center == null) {
223                new Notification(tr("Cannot determine center of selected nodes."))
224                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
225                    .setDuration(Notification.TIME_SHORT)
226                    .show();
227                return;
228            }
229        }
230
231        // Now calculate the average distance to each node from the
232        // center. This method is ok as long as distances are short
233        // relative to the distance from the N or S poles.
234        if (radius == 0) {
235            for (Node n : nodes) {
236                radius += distance(center, n.getEastNorth());
237            }
238            radius = radius / nodes.size();
239        }
240
241        if (!actionAllowed(nodes)) return;
242
243        Collection<Command> cmds = new LinkedList<>();
244
245        // Move each node to that distance from the center.
246        // Nodes that are not "fix" will be adjust making regular arcs.
247        int nodeCount = nodes.size();
248        // Search first fixed node
249        int startPosition;
250        for (startPosition = 0; startPosition < nodeCount; startPosition++) {
251            if (fixNodes.contains(nodes.get(startPosition % nodeCount)))
252                break;
253        }
254        int i = startPosition; // Start position for current arc
255        int j; // End position for current arc
256        while (i < startPosition + nodeCount) {
257            for (j = i + 1; j < startPosition + nodeCount; j++) {
258                if (fixNodes.contains(nodes.get(j % nodeCount)))
259                    break;
260            }
261            Node first = nodes.get(i % nodeCount);
262            PolarCoor pcFirst = new PolarCoor(first.getEastNorth(), center, 0);
263            pcFirst.radius = radius;
264            cmds.add(pcFirst.createMoveCommand(first));
265            if (j > i + 1) {
266                double delta;
267                if (j == i + nodeCount) {
268                    delta = 2 * Math.PI / nodeCount;
269                } else {
270                    PolarCoor pcLast = new PolarCoor(nodes.get(j % nodeCount).getEastNorth(), center, 0);
271                    delta = pcLast.angle - pcFirst.angle;
272                    if (delta < 0) // Assume each PolarCoor.angle is in range ]-pi; pi]
273                        delta +=  2*Math.PI;
274                    delta /= j - i;
275                }
276                for (int k = i+1; k < j; k++) {
277                    PolarCoor p = new PolarCoor(radius, pcFirst.angle + (k-i)*delta, center, 0);
278                    cmds.add(p.createMoveCommand(nodes.get(k % nodeCount)));
279                }
280            }
281            i = j; // Update start point for next iteration
282        }
283
284        Main.main.undoRedo.add(new SequenceCommand(tr("Align Nodes in Circle"), cmds));
285        Main.map.repaint();
286    }
287
288    /**
289     * Collect all nodes with more than one referrer.
290     * @param ways Ways from witch nodes are selected
291     * @return List of nodes with more than one referrer
292     */
293    private static List<Node> collectNodesWithExternReferers(List<Way> ways) {
294        List<Node> withReferrers = new ArrayList<>();
295        for (Way w: ways) {
296            for (Node n: w.getNodes()) {
297                if (n.getReferrers().size() > 1) {
298                    withReferrers.add(n);
299                }
300            }
301        }
302        return withReferrers;
303    }
304
305    /**
306     * Assuming all ways can be joined into polygon, create an ordered list of node.
307     * @param ways List of ways to be joined
308     * @return Nodes anticlockwise ordered
309     */
310    private static List<Node> collectNodesAnticlockwise(List<Way> ways) {
311        List<Node> nodes = new ArrayList<>();
312        Node firstNode = ways.get(0).firstNode();
313        Node lastNode = null;
314        Way lastWay = null;
315        while (firstNode != lastNode) {
316            if (lastNode == null) lastNode = firstNode;
317            for (Way way: ways) {
318                if (way == lastWay) continue;
319                if (way.firstNode() == lastNode) {
320                    List<Node> wayNodes = way.getNodes();
321                    for (int i = 0; i < wayNodes.size() - 1; i++) {
322                        nodes.add(wayNodes.get(i));
323                    }
324                    lastNode = way.lastNode();
325                    lastWay = way;
326                    break;
327                }
328                if (way.lastNode() == lastNode) {
329                    List<Node> wayNodes = way.getNodes();
330                    for (int i = wayNodes.size() - 1; i > 0; i--) {
331                        nodes.add(wayNodes.get(i));
332                    }
333                    lastNode = way.firstNode();
334                    lastWay = way;
335                    break;
336                }
337            }
338        }
339        // Check if nodes are in anticlockwise order
340        int nc = nodes.size();
341        double area = 0;
342        for (int i = 0; i < nc; i++) {
343            EastNorth p1 = nodes.get(i).getEastNorth();
344            EastNorth p2 = nodes.get((i+1) % nc).getEastNorth();
345            area += p1.east()*p2.north() - p2.east()*p1.north();
346        }
347        if (area < 0)
348            Collections.reverse(nodes);
349        return nodes;
350    }
351
352    /**
353     * Check if one or more nodes are outside of download area
354     * @param nodes Nodes to check
355     * @return true if action can be done
356     */
357    private static boolean actionAllowed(Collection<Node> nodes) {
358        boolean outside = false;
359        for (Node n: nodes) {
360            if (n.isOutsideDownloadArea()) {
361                outside = true;
362                break;
363            }
364        }
365        if (outside)
366            new Notification(
367                    tr("One or more nodes involved in this action is outside of the downloaded area."))
368                    .setIcon(JOptionPane.WARNING_MESSAGE)
369                    .setDuration(Notification.TIME_SHORT)
370                    .show();
371        return true;
372    }
373
374    @Override
375    protected void updateEnabledState() {
376        setEnabled(getCurrentDataSet() != null && !getCurrentDataSet().getSelected().isEmpty());
377    }
378
379    @Override
380    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
381        setEnabled(selection != null && !selection.isEmpty());
382    }
383
384    /**
385     * Determines if ways can be joined into a polygon.
386     * @param ways The ways collection to check
387     * @return true if all ways can be joined into a polygon
388     */
389    protected static boolean checkWaysArePolygon(Collection<Way> ways) {
390        // For each way, nodes strictly between first and last should't be reference by an other way
391        for (Way way: ways) {
392            for (Node node: way.getNodes()) {
393                if (way.isFirstLastNode(node)) continue;
394                for (Way wayOther: ways) {
395                    if (way == wayOther) continue;
396                    if (node.getReferrers().contains(wayOther)) return false;
397                }
398            }
399        }
400        // Test if ways can be joined
401        Way currentWay = null;
402        Node startNode = null, endNode = null;
403        int used = 0;
404        while (true) {
405            Way nextWay = null;
406            for (Way w: ways) {
407                if (w.isClosed()) return ways.size() == 1;
408                if (w == currentWay) continue;
409                if (currentWay == null) {
410                    nextWay = w;
411                    startNode = w.firstNode();
412                    endNode = w.lastNode();
413                    break;
414                }
415                if (w.firstNode() == endNode) {
416                    nextWay = w;
417                    endNode = w.lastNode();
418                    break;
419                }
420                if (w.lastNode() == endNode) {
421                    nextWay = w;
422                    endNode = w.firstNode();
423                    break;
424                }
425            }
426            if (nextWay == null) return false;
427            used += 1;
428            currentWay = nextWay;
429            if (endNode == startNode) return used == ways.size();
430        }
431    }
432}