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.Arrays;
011import java.util.Collection;
012import java.util.Collections;
013import java.util.HashMap;
014import java.util.HashSet;
015import java.util.Iterator;
016import java.util.LinkedList;
017import java.util.List;
018import java.util.Map;
019import java.util.Set;
020
021import javax.swing.JOptionPane;
022
023import org.openstreetmap.josm.Main;
024import org.openstreetmap.josm.command.Command;
025import org.openstreetmap.josm.command.MoveCommand;
026import org.openstreetmap.josm.command.SequenceCommand;
027import org.openstreetmap.josm.data.coor.EastNorth;
028import org.openstreetmap.josm.data.coor.PolarCoor;
029import org.openstreetmap.josm.data.osm.Node;
030import org.openstreetmap.josm.data.osm.OsmPrimitive;
031import org.openstreetmap.josm.data.osm.Way;
032import org.openstreetmap.josm.gui.ConditionalOptionPaneUtil;
033import org.openstreetmap.josm.gui.MainApplication;
034import org.openstreetmap.josm.gui.Notification;
035import org.openstreetmap.josm.tools.JosmRuntimeException;
036import org.openstreetmap.josm.tools.Logging;
037import org.openstreetmap.josm.tools.Shortcut;
038import org.openstreetmap.josm.tools.Utils;
039
040/**
041 * Tools / Orthogonalize
042 *
043 * Align edges of a way so all angles are angles of 90 or 180 degrees.
044 * See USAGE String below.
045 */
046public final class OrthogonalizeAction extends JosmAction {
047    private static final String USAGE = tr(
048            "<h3>When one or more ways are selected, the shape is adjusted such, that all angles are 90 or 180 degrees.</h3>"+
049            "You can add two nodes to the selection. Then, the direction is fixed by these two reference nodes. "+
050            "(Afterwards, you can undo the movement for certain nodes:<br>"+
051            "Select them and press the shortcut for Orthogonalize / Undo. The default is Shift-Q.)");
052
053    private static final double EPSILON = 1E-6;
054
055    /**
056     * Constructs a new {@code OrthogonalizeAction}.
057     */
058    public OrthogonalizeAction() {
059        super(tr("Orthogonalize Shape"),
060                "ortho",
061                tr("Move nodes so all angles are 90 or 180 degrees"),
062                Shortcut.registerShortcut("tools:orthogonalize", tr("Tool: {0}", tr("Orthogonalize Shape")),
063                        KeyEvent.VK_Q,
064                        Shortcut.DIRECT), true);
065        putValue("help", ht("/Action/OrthogonalizeShape"));
066    }
067
068    /**
069     * excepted deviation from an angle of 0, 90, 180, 360 degrees
070     * maximum value: 45 degrees
071     *
072     * Current policy is to except just everything, no matter how strange the result would be.
073     */
074    private static final double TOLERANCE1 = Utils.toRadians(45.);   // within a way
075    private static final double TOLERANCE2 = Utils.toRadians(45.);   // ways relative to each other
076
077    /**
078     * Remember movements, so the user can later undo it for certain nodes
079     */
080    private static final Map<Node, EastNorth> rememberMovements = new HashMap<>();
081
082    /**
083     * Undo the previous orthogonalization for certain nodes.
084     *
085     * This is useful, if the way shares nodes that you don't like to change, e.g. imports or
086     * work of another user.
087     *
088     * This action can be triggered by shortcut only.
089     */
090    public static class Undo extends JosmAction {
091        /**
092         * Constructor
093         */
094        public Undo() {
095            super(tr("Orthogonalize Shape / Undo"), "ortho",
096                    tr("Undo orthogonalization for certain nodes"),
097                    Shortcut.registerShortcut("tools:orthogonalizeUndo", tr("Tool: {0}", tr("Orthogonalize Shape / Undo")),
098                            KeyEvent.VK_Q,
099                            Shortcut.SHIFT),
100                    true, "action/orthogonalize/undo", true);
101        }
102
103        @Override
104        public void actionPerformed(ActionEvent e) {
105            if (!isEnabled())
106                return;
107            final Collection<Command> commands = new LinkedList<>();
108            final Collection<OsmPrimitive> sel = getLayerManager().getEditDataSet().getSelected();
109            try {
110                for (OsmPrimitive p : sel) {
111                    if (!(p instanceof Node)) throw new InvalidUserInputException("selected object is not a node");
112                    Node n = (Node) p;
113                    if (rememberMovements.containsKey(n)) {
114                        EastNorth tmp = rememberMovements.get(n);
115                        commands.add(new MoveCommand(n, -tmp.east(), -tmp.north()));
116                        rememberMovements.remove(n);
117                    }
118                }
119                if (!commands.isEmpty()) {
120                    MainApplication.undoRedo.add(new SequenceCommand(tr("Orthogonalize / Undo"), commands));
121                } else {
122                    throw new InvalidUserInputException("Commands are empty");
123                }
124            } catch (InvalidUserInputException ex) {
125                Logging.debug(ex);
126                new Notification(
127                        tr("Orthogonalize Shape / Undo<br>"+
128                        "Please select nodes that were moved by the previous Orthogonalize Shape action!"))
129                        .setIcon(JOptionPane.INFORMATION_MESSAGE)
130                        .show();
131            }
132        }
133
134        @Override
135        protected void updateEnabledState() {
136            updateEnabledStateOnCurrentSelection();
137        }
138
139        @Override
140        protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
141            updateEnabledStateOnModifiableSelection(selection);
142        }
143    }
144
145    @Override
146    public void actionPerformed(ActionEvent e) {
147        if (!isEnabled())
148            return;
149        if ("EPSG:4326".equals(Main.getProjection().toString())) {
150            String msg = tr("<html>You are using the EPSG:4326 projection which might lead<br>" +
151                    "to undesirable results when doing rectangular alignments.<br>" +
152                    "Change your projection to get rid of this warning.<br>" +
153            "Do you want to continue?</html>");
154            if (!ConditionalOptionPaneUtil.showConfirmationDialog(
155                    "align_rectangular_4326",
156                    Main.parent,
157                    msg,
158                    tr("Warning"),
159                    JOptionPane.YES_NO_OPTION,
160                    JOptionPane.QUESTION_MESSAGE,
161                    JOptionPane.YES_OPTION))
162                return;
163        }
164
165        final Collection<OsmPrimitive> sel = getLayerManager().getEditDataSet().getSelected();
166
167        try {
168            final SequenceCommand command = orthogonalize(sel);
169            MainApplication.undoRedo.add(new SequenceCommand(tr("Orthogonalize"), command));
170        } catch (InvalidUserInputException ex) {
171            Logging.debug(ex);
172            String msg;
173            if ("usage".equals(ex.getMessage())) {
174                msg = "<h2>" + tr("Usage") + "</h2>" + USAGE;
175            } else {
176                msg = ex.getMessage() + "<br><hr><h2>" + tr("Usage") + "</h2>" + USAGE;
177            }
178            new Notification(msg)
179                    .setIcon(JOptionPane.INFORMATION_MESSAGE)
180                    .setDuration(Notification.TIME_DEFAULT)
181                    .show();
182        }
183    }
184
185    /**
186     * Rectifies the selection
187     * @param selection the selection which should be rectified
188     * @return a rectifying command
189     * @throws InvalidUserInputException if the selection is invalid
190     */
191    static SequenceCommand orthogonalize(Iterable<OsmPrimitive> selection) throws InvalidUserInputException {
192        final List<Node> nodeList = new ArrayList<>();
193        final List<WayData> wayDataList = new ArrayList<>();
194        // collect nodes and ways from the selection
195        for (OsmPrimitive p : selection) {
196            if (p instanceof Node) {
197                nodeList.add((Node) p);
198            } else if (p instanceof Way) {
199                if (!p.isIncomplete()) {
200                    wayDataList.add(new WayData(((Way) p).getNodes()));
201                }
202            } else {
203                throw new InvalidUserInputException(tr("Selection must consist only of ways and nodes."));
204            }
205        }
206        if (wayDataList.isEmpty() && nodeList.size() > 2) {
207            final WayData data = new WayData(nodeList);
208            final Collection<Command> commands = orthogonalize(Collections.singletonList(data), Collections.<Node>emptyList());
209            return new SequenceCommand(tr("Orthogonalize"), commands);
210        } else if (wayDataList.isEmpty()) {
211            throw new InvalidUserInputException("usage");
212        } else {
213            if (nodeList.size() == 2 || nodeList.isEmpty()) {
214                OrthogonalizeAction.rememberMovements.clear();
215                final Collection<Command> commands = new LinkedList<>();
216
217                if (nodeList.size() == 2) {  // fixed direction
218                    commands.addAll(orthogonalize(wayDataList, nodeList));
219                } else if (nodeList.isEmpty()) {
220                    List<List<WayData>> groups = buildGroups(wayDataList);
221                    for (List<WayData> g: groups) {
222                        commands.addAll(orthogonalize(g, nodeList));
223                    }
224                } else {
225                    throw new IllegalStateException();
226                }
227
228                return new SequenceCommand(tr("Orthogonalize"), commands);
229
230            } else {
231                throw new InvalidUserInputException("usage");
232            }
233        }
234    }
235
236    /**
237     * Collect groups of ways with common nodes in order to orthogonalize each group separately.
238     * @param wayDataList list of ways
239     * @return groups of ways with common nodes
240     */
241    private static List<List<WayData>> buildGroups(List<WayData> wayDataList) {
242        List<List<WayData>> groups = new ArrayList<>();
243        Set<WayData> remaining = new HashSet<>(wayDataList);
244        while (!remaining.isEmpty()) {
245            List<WayData> group = new ArrayList<>();
246            groups.add(group);
247            Iterator<WayData> it = remaining.iterator();
248            WayData next = it.next();
249            it.remove();
250            extendGroupRec(group, next, new ArrayList<>(remaining));
251            remaining.removeAll(group);
252        }
253        return groups;
254    }
255
256    private static void extendGroupRec(List<WayData> group, WayData newGroupMember, List<WayData> remaining) {
257        group.add(newGroupMember);
258        for (int i = 0; i < remaining.size(); ++i) {
259            WayData candidate = remaining.get(i);
260            if (candidate == null) continue;
261            if (!Collections.disjoint(candidate.wayNodes, newGroupMember.wayNodes)) {
262                remaining.set(i, null);
263                extendGroupRec(group, candidate, remaining);
264            }
265        }
266    }
267
268    /**
269     *
270     *  Outline:
271     *  1. Find direction of all segments
272     *      - direction = 0..3 (right,up,left,down)
273     *      - right is not really right, you may have to turn your screen
274     *  2. Find average heading of all segments
275     *      - heading = angle of a vector in polar coordinates
276     *      - sum up horizontal segments (those with direction 0 or 2)
277     *      - sum up vertical segments
278     *      - turn the vertical sum by 90 degrees and add it to the horizontal sum
279     *      - get the average heading from this total sum
280     *  3. Rotate all nodes by the average heading so that right is really right
281     *      and all segments are approximately NS or EW.
282     *  4. If nodes are connected by a horizontal segment: Replace their y-Coordinate by
283     *      the mean value of their y-Coordinates.
284     *      - The same for vertical segments.
285     *  5. Rotate back.
286     * @param wayDataList list of ways
287     * @param headingNodes list of heading nodes
288     * @return list of commands to perform
289     * @throws InvalidUserInputException if selected ways have an angle different from 90 or 180 degrees
290     **/
291    private static Collection<Command> orthogonalize(List<WayData> wayDataList, List<Node> headingNodes) throws InvalidUserInputException {
292        // find average heading
293        double headingAll;
294        try {
295            if (headingNodes.isEmpty()) {
296                // find directions of the segments and make them consistent between different ways
297                wayDataList.get(0).calcDirections(Direction.RIGHT);
298                double refHeading = wayDataList.get(0).heading;
299                EastNorth totSum = new EastNorth(0., 0.);
300                for (WayData w : wayDataList) {
301                    w.calcDirections(Direction.RIGHT);
302                    int directionOffset = angleToDirectionChange(w.heading - refHeading, TOLERANCE2);
303                    w.calcDirections(Direction.RIGHT.changeBy(directionOffset));
304                    if (angleToDirectionChange(refHeading - w.heading, TOLERANCE2) != 0)
305                        throw new JosmRuntimeException("orthogonalize error");
306                    totSum = EN.sum(totSum, w.segSum);
307                }
308                headingAll = EN.polar(new EastNorth(0., 0.), totSum);
309            } else {
310                headingAll = EN.polar(headingNodes.get(0).getEastNorth(), headingNodes.get(1).getEastNorth());
311                for (WayData w : wayDataList) {
312                    w.calcDirections(Direction.RIGHT);
313                    int directionOffset = angleToDirectionChange(w.heading - headingAll, TOLERANCE2);
314                    w.calcDirections(Direction.RIGHT.changeBy(directionOffset));
315                }
316            }
317        } catch (RejectedAngleException ex) {
318            throw new InvalidUserInputException(
319                    tr("<html>Please make sure all selected ways head in a similar direction<br>"+
320                    "or orthogonalize them one by one.</html>"), ex);
321        }
322
323        // put the nodes of all ways in a set
324        final Set<Node> allNodes = new HashSet<>();
325        for (WayData w : wayDataList) {
326            allNodes.addAll(w.wayNodes);
327        }
328
329        // the new x and y value for each node
330        final Map<Node, Double> nX = new HashMap<>();
331        final Map<Node, Double> nY = new HashMap<>();
332
333        // calculate the centroid of all nodes
334        // it is used as rotation center
335        EastNorth pivot = new EastNorth(0., 0.);
336        for (Node n : allNodes) {
337            pivot = EN.sum(pivot, n.getEastNorth());
338        }
339        pivot = new EastNorth(pivot.east() / allNodes.size(), pivot.north() / allNodes.size());
340
341        // rotate
342        for (Node n: allNodes) {
343            EastNorth tmp = EN.rotateCC(pivot, n.getEastNorth(), -headingAll);
344            nX.put(n, tmp.east());
345            nY.put(n, tmp.north());
346        }
347
348        // orthogonalize
349        final Direction[] horizontal = {Direction.RIGHT, Direction.LEFT};
350        final Direction[] vertical = {Direction.UP, Direction.DOWN};
351        final Direction[][] orientations = {horizontal, vertical};
352        for (Direction[] orientation : orientations) {
353            final Set<Node> s = new HashSet<>(allNodes);
354            int size = s.size();
355            for (int dummy = 0; dummy < size; ++dummy) {
356                if (s.isEmpty()) {
357                    break;
358                }
359                final Node dummyN = s.iterator().next();     // pick arbitrary element of s
360
361                final Set<Node> cs = new HashSet<>(); // will contain each node that can be reached from dummyN
362                cs.add(dummyN);                      // walking only on horizontal / vertical segments
363
364                boolean somethingHappened = true;
365                while (somethingHappened) {
366                    somethingHappened = false;
367                    for (WayData w : wayDataList) {
368                        for (int i = 0; i < w.nSeg; ++i) {
369                            Node n1 = w.wayNodes.get(i);
370                            Node n2 = w.wayNodes.get(i+1);
371                            if (Arrays.asList(orientation).contains(w.segDirections[i])) {
372                                if (cs.contains(n1) && !cs.contains(n2)) {
373                                    cs.add(n2);
374                                    somethingHappened = true;
375                                }
376                                if (cs.contains(n2) && !cs.contains(n1)) {
377                                    cs.add(n1);
378                                    somethingHappened = true;
379                                }
380                            }
381                        }
382                    }
383                }
384
385                final Map<Node, Double> nC = (orientation == horizontal) ? nY : nX;
386
387                double average = 0;
388                for (Node n : cs) {
389                    s.remove(n);
390                    average += nC.get(n).doubleValue();
391                }
392                average = average / cs.size();
393
394                // if one of the nodes is a heading node, forget about the average and use its value
395                for (Node fn : headingNodes) {
396                    if (cs.contains(fn)) {
397                        average = nC.get(fn);
398                    }
399                }
400
401                // At this point, the two heading nodes (if any) are horizontally aligned, i.e. they
402                // have the same y coordinate. So in general we shouldn't find them in a vertical string
403                // of segments. This can still happen in some pathological cases (see #7889). To avoid
404                // both heading nodes collapsing to one point, we simply skip this segment string and
405                // don't touch the node coordinates.
406                if (orientation == vertical && headingNodes.size() == 2 && cs.containsAll(headingNodes)) {
407                    continue;
408                }
409
410                for (Node n : cs) {
411                    nC.put(n, average);
412                }
413            }
414            if (!s.isEmpty()) throw new JosmRuntimeException("orthogonalize error");
415        }
416
417        // rotate back and log the change
418        final Collection<Command> commands = new LinkedList<>();
419        for (Node n: allNodes) {
420            EastNorth tmp = new EastNorth(nX.get(n), nY.get(n));
421            tmp = EN.rotateCC(pivot, tmp, headingAll);
422            final double dx = tmp.east() - n.getEastNorth().east();
423            final double dy = tmp.north() - n.getEastNorth().north();
424            if (headingNodes.contains(n)) { // The heading nodes should not have changed
425                if (Math.abs(dx) > Math.abs(EPSILON * tmp.east()) ||
426                    Math.abs(dy) > Math.abs(EPSILON * tmp.east()))
427                    throw new AssertionError("heading node has changed");
428            } else {
429                OrthogonalizeAction.rememberMovements.put(n, new EastNorth(dx, dy));
430                commands.add(new MoveCommand(n, dx, dy));
431            }
432        }
433        return commands;
434    }
435
436    /**
437     * Class contains everything we need to know about a single way.
438     */
439    private static class WayData {
440        /** The assigned way */
441        public final List<Node> wayNodes;
442        /** Number of Segments of the Way */
443        public final int nSeg;
444        /** Number of Nodes of the Way */
445        public final int nNode;
446        /** Direction of the segments */
447        public final Direction[] segDirections;
448        // segment i goes from node i to node (i+1)
449        /** (Vector-)sum of all horizontal segments plus the sum of all vertical */
450        public EastNorth segSum;
451        // segments turned by 90 degrees
452        /** heading of segSum == approximate heading of the way */
453        public double heading;
454
455        WayData(List<Node> wayNodes) {
456            this.wayNodes = wayNodes;
457            this.nNode = wayNodes.size();
458            this.nSeg = nNode - 1;
459            this.segDirections = new Direction[nSeg];
460        }
461
462        /**
463         * Estimate the direction of the segments, given the first segment points in the
464         * direction <code>pInitialDirection</code>.
465         * Then sum up all horizontal / vertical segments to have a good guess for the
466         * heading of the entire way.
467         * @param pInitialDirection initial direction
468         * @throws InvalidUserInputException if selected ways have an angle different from 90 or 180 degrees
469         */
470        public void calcDirections(Direction pInitialDirection) throws InvalidUserInputException {
471            final EastNorth[] en = new EastNorth[nNode]; // alias: wayNodes.get(i).getEastNorth() ---> en[i]
472            for (int i = 0; i < nNode; i++) {
473                en[i] = wayNodes.get(i).getEastNorth();
474            }
475            Direction direction = pInitialDirection;
476            segDirections[0] = direction;
477            for (int i = 0; i < nSeg - 1; i++) {
478                double h1 = EN.polar(en[i], en[i+1]);
479                double h2 = EN.polar(en[i+1], en[i+2]);
480                try {
481                    direction = direction.changeBy(angleToDirectionChange(h2 - h1, TOLERANCE1));
482                } catch (RejectedAngleException ex) {
483                    throw new InvalidUserInputException(tr("Please select ways with angles of approximately 90 or 180 degrees."), ex);
484                }
485                segDirections[i+1] = direction;
486            }
487
488            // sum up segments
489            EastNorth h = new EastNorth(0., 0.);
490            EastNorth v = new EastNorth(0., 0.);
491            for (int i = 0; i < nSeg; ++i) {
492                EastNorth segment = EN.diff(en[i+1], en[i]);
493                if (segDirections[i] == Direction.RIGHT) {
494                    h = EN.sum(h, segment);
495                } else if (segDirections[i] == Direction.UP) {
496                    v = EN.sum(v, segment);
497                } else if (segDirections[i] == Direction.LEFT) {
498                    h = EN.diff(h, segment);
499                } else if (segDirections[i] == Direction.DOWN) {
500                    v = EN.diff(v, segment);
501                } else throw new IllegalStateException();
502            }
503            // rotate the vertical vector by 90 degrees (clockwise) and add it to the horizontal vector
504            segSum = EN.sum(h, new EastNorth(v.north(), -v.east()));
505            this.heading = EN.polar(new EastNorth(0., 0.), segSum);
506        }
507    }
508
509    enum Direction {
510        RIGHT, UP, LEFT, DOWN;
511        public Direction changeBy(int directionChange) {
512            int tmp = (this.ordinal() + directionChange) % 4;
513            if (tmp < 0) {
514                tmp += 4;          // the % operator can return negative value
515            }
516            return Direction.values()[tmp];
517        }
518    }
519
520    /**
521     * Make sure angle (up to 2*Pi) is in interval [ 0, 2*Pi ).
522     * @param a angle
523     * @return correct angle
524     */
525    private static double standardAngle0to2PI(double a) {
526        while (a >= 2 * Math.PI) {
527            a -= 2 * Math.PI;
528        }
529        while (a < 0) {
530            a += 2 * Math.PI;
531        }
532        return a;
533    }
534
535    /**
536     * Make sure angle (up to 2*Pi) is in interval ( -Pi, Pi ].
537     * @param a angle
538     * @return correct angle
539     */
540    private static double standardAngleMPItoPI(double a) {
541        while (a > Math.PI) {
542            a -= 2 * Math.PI;
543        }
544        while (a <= -Math.PI) {
545            a += 2 * Math.PI;
546        }
547        return a;
548    }
549
550    /**
551     * Class contains some auxiliary functions
552     */
553    static final class EN {
554        private EN() {
555            // Hide implicit public constructor for utility class
556        }
557
558        /**
559         * Rotate counter-clock-wise.
560         * @param pivot pivot
561         * @param en original east/north
562         * @param angle angle, in radians
563         * @return new east/north
564         */
565        public static EastNorth rotateCC(EastNorth pivot, EastNorth en, double angle) {
566            double cosPhi = Math.cos(angle);
567            double sinPhi = Math.sin(angle);
568            double x = en.east() - pivot.east();
569            double y = en.north() - pivot.north();
570            double nx = cosPhi * x - sinPhi * y + pivot.east();
571            double ny = sinPhi * x + cosPhi * y + pivot.north();
572            return new EastNorth(nx, ny);
573        }
574
575        public static EastNorth sum(EastNorth en1, EastNorth en2) {
576            return new EastNorth(en1.east() + en2.east(), en1.north() + en2.north());
577        }
578
579        public static EastNorth diff(EastNorth en1, EastNorth en2) {
580            return new EastNorth(en1.east() - en2.east(), en1.north() - en2.north());
581        }
582
583        public static double polar(EastNorth en1, EastNorth en2) {
584            return PolarCoor.computeAngle(en2, en1);
585        }
586    }
587
588    /**
589     * Recognize angle to be approximately 0, 90, 180 or 270 degrees.
590     * returns an integral value, corresponding to a counter clockwise turn.
591     * @param a angle, in radians
592     * @param deltaMax maximum tolerance, in radians
593     * @return an integral value, corresponding to a counter clockwise turn
594     * @throws RejectedAngleException in case of invalid angle
595     */
596    private static int angleToDirectionChange(double a, double deltaMax) throws RejectedAngleException {
597        a = standardAngleMPItoPI(a);
598        double d0 = Math.abs(a);
599        double d90 = Math.abs(a - Math.PI / 2);
600        double dm90 = Math.abs(a + Math.PI / 2);
601        int dirChange;
602        if (d0 < deltaMax) {
603            dirChange = 0;
604        } else if (d90 < deltaMax) {
605            dirChange = 1;
606        } else if (dm90 < deltaMax) {
607            dirChange = -1;
608        } else {
609            a = standardAngle0to2PI(a);
610            double d180 = Math.abs(a - Math.PI);
611            if (d180 < deltaMax) {
612                dirChange = 2;
613            } else
614                throw new RejectedAngleException();
615        }
616        return dirChange;
617    }
618
619    /**
620     * Exception: unsuited user input
621     */
622    protected static class InvalidUserInputException extends Exception {
623        InvalidUserInputException(String message) {
624            super(message);
625        }
626
627        InvalidUserInputException(String message, Throwable cause) {
628            super(message, cause);
629        }
630    }
631
632    /**
633     * Exception: angle cannot be recognized as 0, 90, 180 or 270 degrees
634     */
635    protected static class RejectedAngleException extends Exception {
636        RejectedAngleException() {
637            super();
638        }
639    }
640
641    @Override
642    protected void updateEnabledState() {
643        updateEnabledStateOnCurrentSelection();
644    }
645
646    @Override
647    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
648        updateEnabledStateOnModifiableSelection(selection);
649    }
650}