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.DataSet;
025import org.openstreetmap.josm.data.osm.Node;
026import org.openstreetmap.josm.data.osm.OsmPrimitive;
027import org.openstreetmap.josm.data.osm.Way;
028import org.openstreetmap.josm.gui.Notification;
029import org.openstreetmap.josm.tools.Geometry;
030import org.openstreetmap.josm.tools.Shortcut;
031
032/**
033 * Aligns all selected nodes within a circle. (Useful for roundabouts)
034 *
035 * @author Matthew Newton
036 * @author Petr DlouhĂ˝
037 * @author Teemu Koskinen
038 * @author Alain Delplanque
039 *
040 * @since 146
041 */
042public final class AlignInCircleAction extends JosmAction {
043
044    /**
045     * Constructs a new {@code AlignInCircleAction}.
046     */
047    public AlignInCircleAction() {
048        super(tr("Align Nodes in Circle"), "aligncircle", tr("Move the selected nodes into a circle."),
049                Shortcut.registerShortcut("tools:aligncircle", tr("Tool: {0}", tr("Align Nodes in Circle")),
050                        KeyEvent.VK_O, Shortcut.DIRECT), true);
051        putValue("help", ht("/Action/AlignInCircle"));
052    }
053
054    private static double distance(EastNorth n, EastNorth m) {
055        double easd, nord;
056        easd = n.east() - m.east();
057        nord = n.north() - m.north();
058        return Math.sqrt(easd * easd + nord * nord);
059    }
060
061    public static class PolarCoor {
062        private double radius;
063        private double angle;
064        private EastNorth origin = new EastNorth(0, 0);
065        private double azimuth;
066
067        PolarCoor(double radius, double angle) {
068            this(radius, angle, new EastNorth(0, 0), 0);
069        }
070
071        PolarCoor(double radius, double angle, EastNorth origin, double azimuth) {
072            this.radius = radius;
073            this.angle = angle;
074            this.origin = origin;
075            this.azimuth = azimuth;
076        }
077
078        PolarCoor(EastNorth en) {
079            this(en, new EastNorth(0, 0), 0);
080        }
081
082        PolarCoor(EastNorth en, EastNorth origin, double azimuth) {
083            radius = distance(en, origin);
084            angle = Math.atan2(en.north() - origin.north(), en.east() - origin.east());
085            this.origin = origin;
086            this.azimuth = azimuth;
087        }
088
089        public EastNorth toEastNorth() {
090            return new EastNorth(radius * Math.cos(angle - azimuth) + origin.east(), radius * Math.sin(angle - azimuth)
091                    + origin.north());
092        }
093
094        /**
095         * Create a MoveCommand to move a node to this PolarCoor.
096         * @param n Node to move
097         * @return new MoveCommand
098         */
099        public MoveCommand createMoveCommand(Node n) {
100            EastNorth en = toEastNorth();
101            return new MoveCommand(n, en.east() - n.getEastNorth().east(), en.north() - n.getEastNorth().north());
102        }
103    }
104
105
106    /**
107     * Perform AlignInCircle action.
108     *
109     * A fixed node is a node for which it is forbidden to change the angle relative to center of the circle.
110     * All other nodes are uniformly distributed.
111     *
112     * Case 1: One unclosed way.
113     * --> allow action, and align selected way nodes
114     * If nodes contained by this way are selected, there are fix.
115     * If nodes outside from the way are selected there are ignored.
116     *
117     * Case 2: One or more ways are selected and can be joined into a polygon
118     * --> allow action, and align selected ways nodes
119     * If 1 node outside of way is selected, it became center
120     * If 1 node outside and 1 node inside are selected there define center and radius
121     * If no outside node and 2 inside nodes are selected those 2 nodes define diameter
122     * In all other cases outside nodes are ignored
123     * In all cases, selected nodes are fix, nodes with more than one referrers are fix
124     * (first referrer is the selected way)
125     *
126     * Case 3: Only nodes are selected
127     * --> Align these nodes, all are fix
128     */
129    @Override
130    public void actionPerformed(ActionEvent e) {
131        if (!isEnabled())
132            return;
133
134        Collection<OsmPrimitive> sel = getLayerManager().getEditDataSet().getSelected();
135        List<Node> nodes = new LinkedList<>();
136        // fixNodes: All nodes for which the angle relative to center should not be modified
137        Set<Node> fixNodes = new HashSet<>();
138        List<Way> ways = new LinkedList<>();
139        EastNorth center = null;
140        double radius = 0;
141
142        for (OsmPrimitive osm : sel) {
143            if (osm instanceof Node) {
144                nodes.add((Node) osm);
145            } else if (osm instanceof Way) {
146                ways.add((Way) osm);
147            }
148        }
149
150        if (ways.size() == 1 && !ways.get(0).isClosed()) {
151            // Case 1
152            Way w = ways.get(0);
153            fixNodes.add(w.firstNode());
154            fixNodes.add(w.lastNode());
155            fixNodes.addAll(nodes);
156            fixNodes.addAll(collectNodesWithExternReferers(ways));
157            // Temporary closed way used to reorder nodes
158            Way closedWay = new Way(w);
159            closedWay.addNode(w.firstNode());
160            List<Way> usedWays = new ArrayList<>(1);
161            usedWays.add(closedWay);
162            nodes = collectNodesAnticlockwise(usedWays);
163        } else if (!ways.isEmpty() && checkWaysArePolygon(ways)) {
164            // Case 2
165            List<Node> inside = new ArrayList<>();
166            List<Node> outside = new ArrayList<>();
167
168            for (Node n: nodes) {
169                boolean isInside = false;
170                for (Way w: ways) {
171                    if (w.getNodes().contains(n)) {
172                        isInside = true;
173                        break;
174                    }
175                }
176                if (isInside)
177                    inside.add(n);
178                else
179                    outside.add(n);
180            }
181
182            if (outside.size() == 1 && inside.isEmpty()) {
183                center = outside.get(0).getEastNorth();
184            } else if (outside.size() == 1 && inside.size() == 1) {
185                center = outside.get(0).getEastNorth();
186                radius = distance(center, inside.get(0).getEastNorth());
187            } else if (inside.size() == 2 && outside.isEmpty()) {
188                // 2 nodes inside, define diameter
189                EastNorth en0 = inside.get(0).getEastNorth();
190                EastNorth en1 = inside.get(1).getEastNorth();
191                center = new EastNorth((en0.east() + en1.east()) / 2, (en0.north() + en1.north()) / 2);
192                radius = distance(en0, en1) / 2;
193            }
194
195            fixNodes.addAll(inside);
196            fixNodes.addAll(collectNodesWithExternReferers(ways));
197            nodes = collectNodesAnticlockwise(ways);
198            if (nodes.size() < 4) {
199                new Notification(
200                        tr("Not enough nodes in selected ways."))
201                .setIcon(JOptionPane.INFORMATION_MESSAGE)
202                .setDuration(Notification.TIME_SHORT)
203                .show();
204                return;
205            }
206        } else if (ways.isEmpty() && nodes.size() > 3) {
207            // Case 3
208            fixNodes.addAll(nodes);
209            // No need to reorder nodes since all are fix
210        } else {
211            // Invalid action
212            new Notification(
213                    tr("Please select at least four nodes."))
214                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
215                    .setDuration(Notification.TIME_SHORT)
216                    .show();
217            return;
218        }
219
220        if (center == null) {
221            // Compute the center of nodes
222            center = Geometry.getCenter(nodes);
223            if (center == null) {
224                new Notification(tr("Cannot determine center of selected nodes."))
225                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
226                    .setDuration(Notification.TIME_SHORT)
227                    .show();
228                return;
229            }
230        }
231
232        // Now calculate the average distance to each node from the
233        // center. This method is ok as long as distances are short
234        // relative to the distance from the N or S poles.
235        if (radius == 0) {
236            for (Node n : nodes) {
237                radius += distance(center, n.getEastNorth());
238            }
239            radius = radius / nodes.size();
240        }
241
242        if (!actionAllowed(nodes)) return;
243
244        Collection<Command> cmds = new LinkedList<>();
245
246        // Move each node to that distance from the center.
247        // Nodes that are not "fix" will be adjust making regular arcs.
248        int nodeCount = nodes.size();
249        // Search first fixed node
250        int startPosition;
251        for (startPosition = 0; startPosition < nodeCount; startPosition++) {
252            if (fixNodes.contains(nodes.get(startPosition % nodeCount)))
253                break;
254        }
255        int i = startPosition; // Start position for current arc
256        int j; // End position for current arc
257        while (i < startPosition + nodeCount) {
258            for (j = i + 1; j < startPosition + nodeCount; j++) {
259                if (fixNodes.contains(nodes.get(j % nodeCount)))
260                    break;
261            }
262            Node first = nodes.get(i % nodeCount);
263            PolarCoor pcFirst = new PolarCoor(first.getEastNorth(), center, 0);
264            pcFirst.radius = radius;
265            cmds.add(pcFirst.createMoveCommand(first));
266            if (j > i + 1) {
267                double delta;
268                if (j == i + nodeCount) {
269                    delta = 2 * Math.PI / nodeCount;
270                } else {
271                    PolarCoor pcLast = new PolarCoor(nodes.get(j % nodeCount).getEastNorth(), center, 0);
272                    delta = pcLast.angle - pcFirst.angle;
273                    if (delta < 0) // Assume each PolarCoor.angle is in range ]-pi; pi]
274                        delta += 2*Math.PI;
275                    delta /= j - i;
276                }
277                for (int k = i+1; k < j; k++) {
278                    PolarCoor p = new PolarCoor(radius, pcFirst.angle + (k-i)*delta, center, 0);
279                    cmds.add(p.createMoveCommand(nodes.get(k % nodeCount)));
280                }
281            }
282            i = j; // Update start point for next iteration
283        }
284
285        Main.main.undoRedo.add(new SequenceCommand(tr("Align Nodes in Circle"), cmds));
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        DataSet ds = getLayerManager().getEditDataSet();
377        setEnabled(ds != null && !ds.selectionEmpty());
378    }
379
380    @Override
381    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
382        setEnabled(selection != null && !selection.isEmpty());
383    }
384
385    /**
386     * Determines if ways can be joined into a polygon.
387     * @param ways The ways collection to check
388     * @return true if all ways can be joined into a polygon
389     */
390    private static boolean checkWaysArePolygon(Collection<Way> ways) {
391        // For each way, nodes strictly between first and last should't be reference by an other way
392        for (Way way: ways) {
393            for (Node node: way.getNodes()) {
394                if (way.isFirstLastNode(node)) continue;
395                for (Way wayOther: ways) {
396                    if (way == wayOther) continue;
397                    if (node.getReferrers().contains(wayOther)) return false;
398                }
399            }
400        }
401        // Test if ways can be joined
402        Way currentWay = null;
403        Node startNode = null, endNode = null;
404        int used = 0;
405        while (true) {
406            Way nextWay = null;
407            for (Way w: ways) {
408                if (w.isClosed()) return ways.size() == 1;
409                if (w == currentWay) continue;
410                if (currentWay == null) {
411                    nextWay = w;
412                    startNode = w.firstNode();
413                    endNode = w.lastNode();
414                    break;
415                }
416                if (w.firstNode() == endNode) {
417                    nextWay = w;
418                    endNode = w.lastNode();
419                    break;
420                }
421                if (w.lastNode() == endNode) {
422                    nextWay = w;
423                    endNode = w.firstNode();
424                    break;
425                }
426            }
427            if (nextWay == null) return false;
428            used += 1;
429            currentWay = nextWay;
430            if (endNode == startNode) return used == ways.size();
431        }
432    }
433}