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     * @since 13670
191     */
192    public static SequenceCommand orthogonalize(Iterable<OsmPrimitive> selection) throws InvalidUserInputException {
193        final List<Node> nodeList = new ArrayList<>();
194        final List<WayData> wayDataList = new ArrayList<>();
195        // collect nodes and ways from the selection
196        for (OsmPrimitive p : selection) {
197            if (p instanceof Node) {
198                nodeList.add((Node) p);
199            } else if (p instanceof Way) {
200                if (!p.isIncomplete()) {
201                    wayDataList.add(new WayData(((Way) p).getNodes()));
202                }
203            } else {
204                throw new InvalidUserInputException(tr("Selection must consist only of ways and nodes."));
205            }
206        }
207        if (wayDataList.isEmpty() && nodeList.size() > 2) {
208            final WayData data = new WayData(nodeList);
209            final Collection<Command> commands = orthogonalize(Collections.singletonList(data), Collections.<Node>emptyList());
210            return new SequenceCommand(tr("Orthogonalize"), commands);
211        } else if (wayDataList.isEmpty()) {
212            throw new InvalidUserInputException("usage");
213        } else {
214            if (nodeList.size() == 2 || nodeList.isEmpty()) {
215                OrthogonalizeAction.rememberMovements.clear();
216                final Collection<Command> commands = new LinkedList<>();
217
218                if (nodeList.size() == 2) {  // fixed direction
219                    commands.addAll(orthogonalize(wayDataList, nodeList));
220                } else if (nodeList.isEmpty()) {
221                    List<List<WayData>> groups = buildGroups(wayDataList);
222                    for (List<WayData> g: groups) {
223                        commands.addAll(orthogonalize(g, nodeList));
224                    }
225                } else {
226                    throw new IllegalStateException();
227                }
228
229                return new SequenceCommand(tr("Orthogonalize"), commands);
230
231            } else {
232                throw new InvalidUserInputException("usage");
233            }
234        }
235    }
236
237    /**
238     * Collect groups of ways with common nodes in order to orthogonalize each group separately.
239     * @param wayDataList list of ways
240     * @return groups of ways with common nodes
241     */
242    private static List<List<WayData>> buildGroups(List<WayData> wayDataList) {
243        List<List<WayData>> groups = new ArrayList<>();
244        Set<WayData> remaining = new HashSet<>(wayDataList);
245        while (!remaining.isEmpty()) {
246            List<WayData> group = new ArrayList<>();
247            groups.add(group);
248            Iterator<WayData> it = remaining.iterator();
249            WayData next = it.next();
250            it.remove();
251            extendGroupRec(group, next, new ArrayList<>(remaining));
252            remaining.removeAll(group);
253        }
254        return groups;
255    }
256
257    private static void extendGroupRec(List<WayData> group, WayData newGroupMember, List<WayData> remaining) {
258        group.add(newGroupMember);
259        for (int i = 0; i < remaining.size(); ++i) {
260            WayData candidate = remaining.get(i);
261            if (candidate == null) continue;
262            if (!Collections.disjoint(candidate.wayNodes, newGroupMember.wayNodes)) {
263                remaining.set(i, null);
264                extendGroupRec(group, candidate, remaining);
265            }
266        }
267    }
268
269    /**
270     *
271     *  Outline:
272     *  1. Find direction of all segments
273     *      - direction = 0..3 (right,up,left,down)
274     *      - right is not really right, you may have to turn your screen
275     *  2. Find average heading of all segments
276     *      - heading = angle of a vector in polar coordinates
277     *      - sum up horizontal segments (those with direction 0 or 2)
278     *      - sum up vertical segments
279     *      - turn the vertical sum by 90 degrees and add it to the horizontal sum
280     *      - get the average heading from this total sum
281     *  3. Rotate all nodes by the average heading so that right is really right
282     *      and all segments are approximately NS or EW.
283     *  4. If nodes are connected by a horizontal segment: Replace their y-Coordinate by
284     *      the mean value of their y-Coordinates.
285     *      - The same for vertical segments.
286     *  5. Rotate back.
287     * @param wayDataList list of ways
288     * @param headingNodes list of heading nodes
289     * @return list of commands to perform
290     * @throws InvalidUserInputException if selected ways have an angle different from 90 or 180 degrees
291     **/
292    private static Collection<Command> orthogonalize(List<WayData> wayDataList, List<Node> headingNodes) throws InvalidUserInputException {
293        // find average heading
294        double headingAll;
295        try {
296            if (headingNodes.isEmpty()) {
297                // find directions of the segments and make them consistent between different ways
298                wayDataList.get(0).calcDirections(Direction.RIGHT);
299                double refHeading = wayDataList.get(0).heading;
300                EastNorth totSum = new EastNorth(0., 0.);
301                for (WayData w : wayDataList) {
302                    w.calcDirections(Direction.RIGHT);
303                    int directionOffset = angleToDirectionChange(w.heading - refHeading, TOLERANCE2);
304                    w.calcDirections(Direction.RIGHT.changeBy(directionOffset));
305                    if (angleToDirectionChange(refHeading - w.heading, TOLERANCE2) != 0)
306                        throw new JosmRuntimeException("orthogonalize error");
307                    totSum = EN.sum(totSum, w.segSum);
308                }
309                headingAll = EN.polar(new EastNorth(0., 0.), totSum);
310            } else {
311                headingAll = EN.polar(headingNodes.get(0).getEastNorth(), headingNodes.get(1).getEastNorth());
312                for (WayData w : wayDataList) {
313                    w.calcDirections(Direction.RIGHT);
314                    int directionOffset = angleToDirectionChange(w.heading - headingAll, TOLERANCE2);
315                    w.calcDirections(Direction.RIGHT.changeBy(directionOffset));
316                }
317            }
318        } catch (RejectedAngleException ex) {
319            throw new InvalidUserInputException(
320                    tr("<html>Please make sure all selected ways head in a similar direction<br>"+
321                    "or orthogonalize them one by one.</html>"), ex);
322        }
323
324        // put the nodes of all ways in a set
325        final Set<Node> allNodes = new HashSet<>();
326        for (WayData w : wayDataList) {
327            allNodes.addAll(w.wayNodes);
328        }
329
330        // the new x and y value for each node
331        final Map<Node, Double> nX = new HashMap<>();
332        final Map<Node, Double> nY = new HashMap<>();
333
334        // calculate the centroid of all nodes
335        // it is used as rotation center
336        EastNorth pivot = new EastNorth(0., 0.);
337        for (Node n : allNodes) {
338            pivot = EN.sum(pivot, n.getEastNorth());
339        }
340        pivot = new EastNorth(pivot.east() / allNodes.size(), pivot.north() / allNodes.size());
341
342        // rotate
343        for (Node n: allNodes) {
344            EastNorth tmp = EN.rotateCC(pivot, n.getEastNorth(), -headingAll);
345            nX.put(n, tmp.east());
346            nY.put(n, tmp.north());
347        }
348
349        // orthogonalize
350        final Direction[] horizontal = {Direction.RIGHT, Direction.LEFT};
351        final Direction[] vertical = {Direction.UP, Direction.DOWN};
352        final Direction[][] orientations = {horizontal, vertical};
353        for (Direction[] orientation : orientations) {
354            final Set<Node> s = new HashSet<>(allNodes);
355            int size = s.size();
356            for (int dummy = 0; dummy < size; ++dummy) {
357                if (s.isEmpty()) {
358                    break;
359                }
360                final Node dummyN = s.iterator().next();     // pick arbitrary element of s
361
362                final Set<Node> cs = new HashSet<>(); // will contain each node that can be reached from dummyN
363                cs.add(dummyN);                      // walking only on horizontal / vertical segments
364
365                boolean somethingHappened = true;
366                while (somethingHappened) {
367                    somethingHappened = false;
368                    for (WayData w : wayDataList) {
369                        for (int i = 0; i < w.nSeg; ++i) {
370                            Node n1 = w.wayNodes.get(i);
371                            Node n2 = w.wayNodes.get(i+1);
372                            if (Arrays.asList(orientation).contains(w.segDirections[i])) {
373                                if (cs.contains(n1) && !cs.contains(n2)) {
374                                    cs.add(n2);
375                                    somethingHappened = true;
376                                }
377                                if (cs.contains(n2) && !cs.contains(n1)) {
378                                    cs.add(n1);
379                                    somethingHappened = true;
380                                }
381                            }
382                        }
383                    }
384                }
385
386                final Map<Node, Double> nC = (orientation == horizontal) ? nY : nX;
387
388                double average = 0;
389                for (Node n : cs) {
390                    s.remove(n);
391                    average += nC.get(n).doubleValue();
392                }
393                average = average / cs.size();
394
395                // if one of the nodes is a heading node, forget about the average and use its value
396                for (Node fn : headingNodes) {
397                    if (cs.contains(fn)) {
398                        average = nC.get(fn);
399                    }
400                }
401
402                // At this point, the two heading nodes (if any) are horizontally aligned, i.e. they
403                // have the same y coordinate. So in general we shouldn't find them in a vertical string
404                // of segments. This can still happen in some pathological cases (see #7889). To avoid
405                // both heading nodes collapsing to one point, we simply skip this segment string and
406                // don't touch the node coordinates.
407                if (orientation == vertical && headingNodes.size() == 2 && cs.containsAll(headingNodes)) {
408                    continue;
409                }
410
411                for (Node n : cs) {
412                    nC.put(n, average);
413                }
414            }
415            if (!s.isEmpty()) throw new JosmRuntimeException("orthogonalize error");
416        }
417
418        // rotate back and log the change
419        final Collection<Command> commands = new LinkedList<>();
420        for (Node n: allNodes) {
421            EastNorth tmp = new EastNorth(nX.get(n), nY.get(n));
422            tmp = EN.rotateCC(pivot, tmp, headingAll);
423            final double dx = tmp.east() - n.getEastNorth().east();
424            final double dy = tmp.north() - n.getEastNorth().north();
425            if (headingNodes.contains(n)) { // The heading nodes should not have changed
426                if (Math.abs(dx) > Math.abs(EPSILON * tmp.east()) ||
427                    Math.abs(dy) > Math.abs(EPSILON * tmp.east()))
428                    throw new AssertionError("heading node has changed");
429            } else {
430                OrthogonalizeAction.rememberMovements.put(n, new EastNorth(dx, dy));
431                commands.add(new MoveCommand(n, dx, dy));
432            }
433        }
434        return commands;
435    }
436
437    /**
438     * Class contains everything we need to know about a single way.
439     */
440    private static class WayData {
441        /** The assigned way */
442        public final List<Node> wayNodes;
443        /** Number of Segments of the Way */
444        public final int nSeg;
445        /** Number of Nodes of the Way */
446        public final int nNode;
447        /** Direction of the segments */
448        public final Direction[] segDirections;
449        // segment i goes from node i to node (i+1)
450        /** (Vector-)sum of all horizontal segments plus the sum of all vertical */
451        public EastNorth segSum;
452        // segments turned by 90 degrees
453        /** heading of segSum == approximate heading of the way */
454        public double heading;
455
456        WayData(List<Node> wayNodes) {
457            this.wayNodes = wayNodes;
458            this.nNode = wayNodes.size();
459            this.nSeg = nNode - 1;
460            this.segDirections = new Direction[nSeg];
461        }
462
463        /**
464         * Estimate the direction of the segments, given the first segment points in the
465         * direction <code>pInitialDirection</code>.
466         * Then sum up all horizontal / vertical segments to have a good guess for the
467         * heading of the entire way.
468         * @param pInitialDirection initial direction
469         * @throws InvalidUserInputException if selected ways have an angle different from 90 or 180 degrees
470         */
471        public void calcDirections(Direction pInitialDirection) throws InvalidUserInputException {
472            final EastNorth[] en = new EastNorth[nNode]; // alias: wayNodes.get(i).getEastNorth() ---> en[i]
473            for (int i = 0; i < nNode; i++) {
474                en[i] = wayNodes.get(i).getEastNorth();
475            }
476            Direction direction = pInitialDirection;
477            segDirections[0] = direction;
478            for (int i = 0; i < nSeg - 1; i++) {
479                double h1 = EN.polar(en[i], en[i+1]);
480                double h2 = EN.polar(en[i+1], en[i+2]);
481                try {
482                    direction = direction.changeBy(angleToDirectionChange(h2 - h1, TOLERANCE1));
483                } catch (RejectedAngleException ex) {
484                    throw new InvalidUserInputException(tr("Please select ways with angles of approximately 90 or 180 degrees."), ex);
485                }
486                segDirections[i+1] = direction;
487            }
488
489            // sum up segments
490            EastNorth h = new EastNorth(0., 0.);
491            EastNorth v = new EastNorth(0., 0.);
492            for (int i = 0; i < nSeg; ++i) {
493                EastNorth segment = EN.diff(en[i+1], en[i]);
494                if (segDirections[i] == Direction.RIGHT) {
495                    h = EN.sum(h, segment);
496                } else if (segDirections[i] == Direction.UP) {
497                    v = EN.sum(v, segment);
498                } else if (segDirections[i] == Direction.LEFT) {
499                    h = EN.diff(h, segment);
500                } else if (segDirections[i] == Direction.DOWN) {
501                    v = EN.diff(v, segment);
502                } else throw new IllegalStateException();
503            }
504            // rotate the vertical vector by 90 degrees (clockwise) and add it to the horizontal vector
505            segSum = EN.sum(h, new EastNorth(v.north(), -v.east()));
506            this.heading = EN.polar(new EastNorth(0., 0.), segSum);
507        }
508    }
509
510    enum Direction {
511        RIGHT, UP, LEFT, DOWN;
512        public Direction changeBy(int directionChange) {
513            int tmp = (this.ordinal() + directionChange) % 4;
514            if (tmp < 0) {
515                tmp += 4;          // the % operator can return negative value
516            }
517            return Direction.values()[tmp];
518        }
519    }
520
521    /**
522     * Make sure angle (up to 2*Pi) is in interval [ 0, 2*Pi ).
523     * @param a angle
524     * @return correct angle
525     */
526    private static double standardAngle0to2PI(double a) {
527        while (a >= 2 * Math.PI) {
528            a -= 2 * Math.PI;
529        }
530        while (a < 0) {
531            a += 2 * Math.PI;
532        }
533        return a;
534    }
535
536    /**
537     * Make sure angle (up to 2*Pi) is in interval ( -Pi, Pi ].
538     * @param a angle
539     * @return correct angle
540     */
541    private static double standardAngleMPItoPI(double a) {
542        while (a > Math.PI) {
543            a -= 2 * Math.PI;
544        }
545        while (a <= -Math.PI) {
546            a += 2 * Math.PI;
547        }
548        return a;
549    }
550
551    /**
552     * Class contains some auxiliary functions
553     */
554    static final class EN {
555        private EN() {
556            // Hide implicit public constructor for utility class
557        }
558
559        /**
560         * Rotate counter-clock-wise.
561         * @param pivot pivot
562         * @param en original east/north
563         * @param angle angle, in radians
564         * @return new east/north
565         */
566        public static EastNorth rotateCC(EastNorth pivot, EastNorth en, double angle) {
567            double cosPhi = Math.cos(angle);
568            double sinPhi = Math.sin(angle);
569            double x = en.east() - pivot.east();
570            double y = en.north() - pivot.north();
571            double nx = cosPhi * x - sinPhi * y + pivot.east();
572            double ny = sinPhi * x + cosPhi * y + pivot.north();
573            return new EastNorth(nx, ny);
574        }
575
576        public static EastNorth sum(EastNorth en1, EastNorth en2) {
577            return new EastNorth(en1.east() + en2.east(), en1.north() + en2.north());
578        }
579
580        public static EastNorth diff(EastNorth en1, EastNorth en2) {
581            return new EastNorth(en1.east() - en2.east(), en1.north() - en2.north());
582        }
583
584        public static double polar(EastNorth en1, EastNorth en2) {
585            return PolarCoor.computeAngle(en2, en1);
586        }
587    }
588
589    /**
590     * Recognize angle to be approximately 0, 90, 180 or 270 degrees.
591     * returns an integral value, corresponding to a counter clockwise turn.
592     * @param a angle, in radians
593     * @param deltaMax maximum tolerance, in radians
594     * @return an integral value, corresponding to a counter clockwise turn
595     * @throws RejectedAngleException in case of invalid angle
596     */
597    private static int angleToDirectionChange(double a, double deltaMax) throws RejectedAngleException {
598        a = standardAngleMPItoPI(a);
599        double d0 = Math.abs(a);
600        double d90 = Math.abs(a - Math.PI / 2);
601        double dm90 = Math.abs(a + Math.PI / 2);
602        int dirChange;
603        if (d0 < deltaMax) {
604            dirChange = 0;
605        } else if (d90 < deltaMax) {
606            dirChange = 1;
607        } else if (dm90 < deltaMax) {
608            dirChange = -1;
609        } else {
610            a = standardAngle0to2PI(a);
611            double d180 = Math.abs(a - Math.PI);
612            if (d180 < deltaMax) {
613                dirChange = 2;
614            } else
615                throw new RejectedAngleException();
616        }
617        return dirChange;
618    }
619
620    /**
621     * Exception: unsuited user input
622     * @since 13670
623     */
624    public static final class InvalidUserInputException extends Exception {
625        InvalidUserInputException(String message) {
626            super(message);
627        }
628
629        InvalidUserInputException(String message, Throwable cause) {
630            super(message, cause);
631        }
632    }
633
634    /**
635     * Exception: angle cannot be recognized as 0, 90, 180 or 270 degrees
636     */
637    protected static class RejectedAngleException extends Exception {
638        RejectedAngleException() {
639            super();
640        }
641    }
642
643    @Override
644    protected void updateEnabledState() {
645        updateEnabledStateOnCurrentSelection();
646    }
647
648    @Override
649    protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
650        updateEnabledStateOnModifiableSelection(selection);
651    }
652}