source: josm/trunk/src/org/openstreetmap/josm/actions/OrthogonalizeAction.java@ 10659

Last change on this file since 10659 was 10467, checked in by Don-vip, 8 years ago

fix #13037 - Small fixes for unit tests (patch by michael2402) - gsoc-core
  • Property svn:eol-style set to native
File size: 25.7 KB
Line 
1// License: GPL. For details, see LICENSE file.
2package org.openstreetmap.josm.actions;
3
4import static org.openstreetmap.josm.gui.help.HelpUtil.ht;
5import static org.openstreetmap.josm.tools.I18n.tr;
6
7import java.awt.event.ActionEvent;
8import java.awt.event.KeyEvent;
9import java.util.ArrayList;
10import java.util.Arrays;
11import java.util.Collection;
12import java.util.Collections;
13import java.util.HashMap;
14import java.util.HashSet;
15import java.util.Iterator;
16import java.util.LinkedList;
17import java.util.List;
18import java.util.Map;
19import java.util.Set;
20
21import javax.swing.JOptionPane;
22
23import org.openstreetmap.josm.Main;
24import org.openstreetmap.josm.command.Command;
25import org.openstreetmap.josm.command.MoveCommand;
26import org.openstreetmap.josm.command.SequenceCommand;
27import org.openstreetmap.josm.data.coor.EastNorth;
28import org.openstreetmap.josm.data.osm.DataSet;
29import org.openstreetmap.josm.data.osm.Node;
30import org.openstreetmap.josm.data.osm.OsmPrimitive;
31import org.openstreetmap.josm.data.osm.Way;
32import org.openstreetmap.josm.gui.ConditionalOptionPaneUtil;
33import org.openstreetmap.josm.gui.Notification;
34import org.openstreetmap.josm.tools.Shortcut;
35
36/**
37 * Tools / Orthogonalize
38 *
39 * Align edges of a way so all angles are angles of 90 or 180 degrees.
40 * See USAGE String below.
41 */
42public final class OrthogonalizeAction extends JosmAction {
43 private static final String USAGE = tr(
44 "<h3>When one or more ways are selected, the shape is adjusted such, that all angles are 90 or 180 degrees.</h3>"+
45 "You can add two nodes to the selection. Then, the direction is fixed by these two reference nodes. "+
46 "(Afterwards, you can undo the movement for certain nodes:<br>"+
47 "Select them and press the shortcut for Orthogonalize / Undo. The default is Shift-Q.)");
48
49 /**
50 * Constructs a new {@code OrthogonalizeAction}.
51 */
52 public OrthogonalizeAction() {
53 super(tr("Orthogonalize Shape"),
54 "ortho",
55 tr("Move nodes so all angles are 90 or 180 degrees"),
56 Shortcut.registerShortcut("tools:orthogonalize", tr("Tool: {0}", tr("Orthogonalize Shape")),
57 KeyEvent.VK_Q,
58 Shortcut.DIRECT), true);
59 putValue("help", ht("/Action/OrthogonalizeShape"));
60 }
61
62 /**
63 * excepted deviation from an angle of 0, 90, 180, 360 degrees
64 * maximum value: 45 degrees
65 *
66 * Current policy is to except just everything, no matter how strange the result would be.
67 */
68 private static final double TOLERANCE1 = Math.toRadians(45.); // within a way
69 private static final double TOLERANCE2 = Math.toRadians(45.); // ways relative to each other
70
71 /**
72 * Remember movements, so the user can later undo it for certain nodes
73 */
74 private static final Map<Node, EastNorth> rememberMovements = new HashMap<>();
75
76 /**
77 * Undo the previous orthogonalization for certain nodes.
78 *
79 * This is useful, if the way shares nodes that you don't like to change, e.g. imports or
80 * work of another user.
81 *
82 * This action can be triggered by shortcut only.
83 */
84 public static class Undo extends JosmAction {
85 /**
86 * Constructor
87 */
88 public Undo() {
89 super(tr("Orthogonalize Shape / Undo"), "ortho",
90 tr("Undo orthogonalization for certain nodes"),
91 Shortcut.registerShortcut("tools:orthogonalizeUndo", tr("Tool: {0}", tr("Orthogonalize Shape / Undo")),
92 KeyEvent.VK_Q,
93 Shortcut.SHIFT),
94 true, "action/orthogonalize/undo", true);
95 }
96
97 @Override
98 public void actionPerformed(ActionEvent e) {
99 if (!isEnabled())
100 return;
101 final Collection<Command> commands = new LinkedList<>();
102 final Collection<OsmPrimitive> sel = getLayerManager().getEditDataSet().getSelected();
103 try {
104 for (OsmPrimitive p : sel) {
105 if (!(p instanceof Node)) throw new InvalidUserInputException("selected object is not a node");
106 Node n = (Node) p;
107 if (rememberMovements.containsKey(n)) {
108 EastNorth tmp = rememberMovements.get(n);
109 commands.add(new MoveCommand(n, -tmp.east(), -tmp.north()));
110 rememberMovements.remove(n);
111 }
112 }
113 if (!commands.isEmpty()) {
114 Main.main.undoRedo.add(new SequenceCommand(tr("Orthogonalize / Undo"), commands));
115 } else {
116 throw new InvalidUserInputException("Commands are empty");
117 }
118 } catch (InvalidUserInputException ex) {
119 Main.debug(ex);
120 new Notification(
121 tr("Orthogonalize Shape / Undo<br>"+
122 "Please select nodes that were moved by the previous Orthogonalize Shape action!"))
123 .setIcon(JOptionPane.INFORMATION_MESSAGE)
124 .show();
125 }
126 }
127 }
128
129 @Override
130 public void actionPerformed(ActionEvent e) {
131 if (!isEnabled())
132 return;
133 if ("EPSG:4326".equals(Main.getProjection().toString())) {
134 String msg = tr("<html>You are using the EPSG:4326 projection which might lead<br>" +
135 "to undesirable results when doing rectangular alignments.<br>" +
136 "Change your projection to get rid of this warning.<br>" +
137 "Do you want to continue?</html>");
138 if (!ConditionalOptionPaneUtil.showConfirmationDialog(
139 "align_rectangular_4326",
140 Main.parent,
141 msg,
142 tr("Warning"),
143 JOptionPane.YES_NO_OPTION,
144 JOptionPane.QUESTION_MESSAGE,
145 JOptionPane.YES_OPTION))
146 return;
147 }
148
149 final Collection<OsmPrimitive> sel = getLayerManager().getEditDataSet().getSelected();
150
151 try {
152 final SequenceCommand command = orthogonalize(sel);
153 Main.main.undoRedo.add(new SequenceCommand(tr("Orthogonalize"), command));
154 } catch (InvalidUserInputException ex) {
155 Main.debug(ex);
156 String msg;
157 if ("usage".equals(ex.getMessage())) {
158 msg = "<h2>" + tr("Usage") + "</h2>" + USAGE;
159 } else {
160 msg = ex.getMessage() + "<br><hr><h2>" + tr("Usage") + "</h2>" + USAGE;
161 }
162 new Notification(msg)
163 .setIcon(JOptionPane.INFORMATION_MESSAGE)
164 .setDuration(Notification.TIME_DEFAULT)
165 .show();
166 }
167 }
168
169 /**
170 * Rectifies the selection
171 * @param selection the selection which should be rectified
172 * @return a rectifying command
173 * @throws InvalidUserInputException if the selection is invalid
174 */
175 static SequenceCommand orthogonalize(Iterable<OsmPrimitive> selection) throws InvalidUserInputException {
176 final List<Node> nodeList = new ArrayList<>();
177 final List<WayData> wayDataList = new ArrayList<>();
178 // collect nodes and ways from the selection
179 for (OsmPrimitive p : selection) {
180 if (p instanceof Node) {
181 nodeList.add((Node) p);
182 } else if (p instanceof Way) {
183 wayDataList.add(new WayData(((Way) p).getNodes()));
184 } else {
185 throw new InvalidUserInputException(tr("Selection must consist only of ways and nodes."));
186 }
187 }
188 if (wayDataList.isEmpty() && nodeList.size() > 2) {
189 final WayData data = new WayData(nodeList);
190 final Collection<Command> commands = orthogonalize(Collections.singletonList(data), Collections.<Node>emptyList());
191 return new SequenceCommand(tr("Orthogonalize"), commands);
192 } else if (wayDataList.isEmpty()) {
193 throw new InvalidUserInputException("usage");
194 } else {
195 if (nodeList.size() == 2 || nodeList.isEmpty()) {
196 OrthogonalizeAction.rememberMovements.clear();
197 final Collection<Command> commands = new LinkedList<>();
198
199 if (nodeList.size() == 2) { // fixed direction
200 commands.addAll(orthogonalize(wayDataList, nodeList));
201 } else if (nodeList.isEmpty()) {
202 List<List<WayData>> groups = buildGroups(wayDataList);
203 for (List<WayData> g: groups) {
204 commands.addAll(orthogonalize(g, nodeList));
205 }
206 } else {
207 throw new IllegalStateException();
208 }
209
210 return new SequenceCommand(tr("Orthogonalize"), commands);
211
212 } else {
213 throw new InvalidUserInputException("usage");
214 }
215 }
216 }
217
218 /**
219 * Collect groups of ways with common nodes in order to orthogonalize each group separately.
220 * @param wayDataList list of ways
221 * @return groups of ways with common nodes
222 */
223 private static List<List<WayData>> buildGroups(List<WayData> wayDataList) {
224 List<List<WayData>> groups = new ArrayList<>();
225 Set<WayData> remaining = new HashSet<>(wayDataList);
226 while (!remaining.isEmpty()) {
227 List<WayData> group = new ArrayList<>();
228 groups.add(group);
229 Iterator<WayData> it = remaining.iterator();
230 WayData next = it.next();
231 it.remove();
232 extendGroupRec(group, next, new ArrayList<>(remaining));
233 remaining.removeAll(group);
234 }
235 return groups;
236 }
237
238 private static void extendGroupRec(List<WayData> group, WayData newGroupMember, List<WayData> remaining) {
239 group.add(newGroupMember);
240 for (int i = 0; i < remaining.size(); ++i) {
241 WayData candidate = remaining.get(i);
242 if (candidate == null) continue;
243 if (!Collections.disjoint(candidate.wayNodes, newGroupMember.wayNodes)) {
244 remaining.set(i, null);
245 extendGroupRec(group, candidate, remaining);
246 }
247 }
248 }
249
250 /**
251 *
252 * Outline:
253 * 1. Find direction of all segments
254 * - direction = 0..3 (right,up,left,down)
255 * - right is not really right, you may have to turn your screen
256 * 2. Find average heading of all segments
257 * - heading = angle of a vector in polar coordinates
258 * - sum up horizontal segments (those with direction 0 or 2)
259 * - sum up vertical segments
260 * - turn the vertical sum by 90 degrees and add it to the horizontal sum
261 * - get the average heading from this total sum
262 * 3. Rotate all nodes by the average heading so that right is really right
263 * and all segments are approximately NS or EW.
264 * 4. If nodes are connected by a horizontal segment: Replace their y-Coordinate by
265 * the mean value of their y-Coordinates.
266 * - The same for vertical segments.
267 * 5. Rotate back.
268 * @param wayDataList list of ways
269 * @param headingNodes list of heading nodes
270 * @return list of commands to perform
271 * @throws InvalidUserInputException if selected ways have an angle different from 90 or 180 degrees
272 **/
273 private static Collection<Command> orthogonalize(List<WayData> wayDataList, List<Node> headingNodes) throws InvalidUserInputException {
274 // find average heading
275 double headingAll;
276 try {
277 if (headingNodes.isEmpty()) {
278 // find directions of the segments and make them consistent between different ways
279 wayDataList.get(0).calcDirections(Direction.RIGHT);
280 double refHeading = wayDataList.get(0).heading;
281 EastNorth totSum = new EastNorth(0., 0.);
282 for (WayData w : wayDataList) {
283 w.calcDirections(Direction.RIGHT);
284 int directionOffset = angleToDirectionChange(w.heading - refHeading, TOLERANCE2);
285 w.calcDirections(Direction.RIGHT.changeBy(directionOffset));
286 if (angleToDirectionChange(refHeading - w.heading, TOLERANCE2) != 0)
287 throw new RuntimeException();
288 totSum = EN.sum(totSum, w.segSum);
289 }
290 headingAll = EN.polar(new EastNorth(0., 0.), totSum);
291 } else {
292 headingAll = EN.polar(headingNodes.get(0).getEastNorth(), headingNodes.get(1).getEastNorth());
293 for (WayData w : wayDataList) {
294 w.calcDirections(Direction.RIGHT);
295 int directionOffset = angleToDirectionChange(w.heading - headingAll, TOLERANCE2);
296 w.calcDirections(Direction.RIGHT.changeBy(directionOffset));
297 }
298 }
299 } catch (RejectedAngleException ex) {
300 throw new InvalidUserInputException(
301 tr("<html>Please make sure all selected ways head in a similar direction<br>"+
302 "or orthogonalize them one by one.</html>"), ex);
303 }
304
305 // put the nodes of all ways in a set
306 final Set<Node> allNodes = new HashSet<>();
307 for (WayData w : wayDataList) {
308 allNodes.addAll(w.wayNodes);
309 }
310
311 // the new x and y value for each node
312 final Map<Node, Double> nX = new HashMap<>();
313 final Map<Node, Double> nY = new HashMap<>();
314
315 // calculate the centroid of all nodes
316 // it is used as rotation center
317 EastNorth pivot = new EastNorth(0., 0.);
318 for (Node n : allNodes) {
319 pivot = EN.sum(pivot, n.getEastNorth());
320 }
321 pivot = new EastNorth(pivot.east() / allNodes.size(), pivot.north() / allNodes.size());
322
323 // rotate
324 for (Node n: allNodes) {
325 EastNorth tmp = EN.rotateCC(pivot, n.getEastNorth(), -headingAll);
326 nX.put(n, tmp.east());
327 nY.put(n, tmp.north());
328 }
329
330 // orthogonalize
331 final Direction[] horizontal = {Direction.RIGHT, Direction.LEFT};
332 final Direction[] vertical = {Direction.UP, Direction.DOWN};
333 final Direction[][] orientations = {horizontal, vertical};
334 for (Direction[] orientation : orientations) {
335 final Set<Node> s = new HashSet<>(allNodes);
336 int size = s.size();
337 for (int dummy = 0; dummy < size; ++dummy) {
338 if (s.isEmpty()) {
339 break;
340 }
341 final Node dummyN = s.iterator().next(); // pick arbitrary element of s
342
343 final Set<Node> cs = new HashSet<>(); // will contain each node that can be reached from dummyN
344 cs.add(dummyN); // walking only on horizontal / vertical segments
345
346 boolean somethingHappened = true;
347 while (somethingHappened) {
348 somethingHappened = false;
349 for (WayData w : wayDataList) {
350 for (int i = 0; i < w.nSeg; ++i) {
351 Node n1 = w.wayNodes.get(i);
352 Node n2 = w.wayNodes.get(i+1);
353 if (Arrays.asList(orientation).contains(w.segDirections[i])) {
354 if (cs.contains(n1) && !cs.contains(n2)) {
355 cs.add(n2);
356 somethingHappened = true;
357 }
358 if (cs.contains(n2) && !cs.contains(n1)) {
359 cs.add(n1);
360 somethingHappened = true;
361 }
362 }
363 }
364 }
365 }
366
367 final Map<Node, Double> nC = (orientation == horizontal) ? nY : nX;
368
369 double average = 0;
370 for (Node n : cs) {
371 s.remove(n);
372 average += nC.get(n).doubleValue();
373 }
374 average = average / cs.size();
375
376 // if one of the nodes is a heading node, forget about the average and use its value
377 for (Node fn : headingNodes) {
378 if (cs.contains(fn)) {
379 average = nC.get(fn);
380 }
381 }
382
383 // At this point, the two heading nodes (if any) are horizontally aligned, i.e. they
384 // have the same y coordinate. So in general we shouldn't find them in a vertical string
385 // of segments. This can still happen in some pathological cases (see #7889). To avoid
386 // both heading nodes collapsing to one point, we simply skip this segment string and
387 // don't touch the node coordinates.
388 if (orientation == vertical && headingNodes.size() == 2 && cs.containsAll(headingNodes)) {
389 continue;
390 }
391
392 for (Node n : cs) {
393 nC.put(n, average);
394 }
395 }
396 if (!s.isEmpty()) throw new RuntimeException();
397 }
398
399 // rotate back and log the change
400 final Collection<Command> commands = new LinkedList<>();
401 for (Node n: allNodes) {
402 EastNorth tmp = new EastNorth(nX.get(n), nY.get(n));
403 tmp = EN.rotateCC(pivot, tmp, headingAll);
404 final double dx = tmp.east() - n.getEastNorth().east();
405 final double dy = tmp.north() - n.getEastNorth().north();
406 if (headingNodes.contains(n)) { // The heading nodes should not have changed
407 final double epsilon = 1E-6;
408 if (Math.abs(dx) > Math.abs(epsilon * tmp.east()) ||
409 Math.abs(dy) > Math.abs(epsilon * tmp.east()))
410 throw new AssertionError();
411 } else {
412 OrthogonalizeAction.rememberMovements.put(n, new EastNorth(dx, dy));
413 commands.add(new MoveCommand(n, dx, dy));
414 }
415 }
416 return commands;
417 }
418
419 /**
420 * Class contains everything we need to know about a single way.
421 */
422 private static class WayData {
423 public final List<Node> wayNodes; // The assigned way
424 public final int nSeg; // Number of Segments of the Way
425 public final int nNode; // Number of Nodes of the Way
426 public final Direction[] segDirections; // Direction of the segments
427 // segment i goes from node i to node (i+1)
428 public EastNorth segSum; // (Vector-)sum of all horizontal segments plus the sum of all vertical
429 // segments turned by 90 degrees
430 public double heading; // heading of segSum == approximate heading of the way
431
432 WayData(List<Node> wayNodes) {
433 this.wayNodes = wayNodes;
434 this.nNode = wayNodes.size();
435 this.nSeg = nNode - 1;
436 this.segDirections = new Direction[nSeg];
437 }
438
439 /**
440 * Estimate the direction of the segments, given the first segment points in the
441 * direction <code>pInitialDirection</code>.
442 * Then sum up all horizontal / vertical segments to have a good guess for the
443 * heading of the entire way.
444 * @param pInitialDirection initial direction
445 * @throws InvalidUserInputException if selected ways have an angle different from 90 or 180 degrees
446 */
447 public void calcDirections(Direction pInitialDirection) throws InvalidUserInputException {
448 final EastNorth[] en = new EastNorth[nNode]; // alias: wayNodes.get(i).getEastNorth() ---> en[i]
449 for (int i = 0; i < nNode; i++) {
450 en[i] = wayNodes.get(i).getEastNorth();
451 }
452 Direction direction = pInitialDirection;
453 segDirections[0] = direction;
454 for (int i = 0; i < nSeg - 1; i++) {
455 double h1 = EN.polar(en[i], en[i+1]);
456 double h2 = EN.polar(en[i+1], en[i+2]);
457 try {
458 direction = direction.changeBy(angleToDirectionChange(h2 - h1, TOLERANCE1));
459 } catch (RejectedAngleException ex) {
460 throw new InvalidUserInputException(tr("Please select ways with angles of approximately 90 or 180 degrees."), ex);
461 }
462 segDirections[i+1] = direction;
463 }
464
465 // sum up segments
466 EastNorth h = new EastNorth(0., 0.);
467 EastNorth v = new EastNorth(0., 0.);
468 for (int i = 0; i < nSeg; ++i) {
469 EastNorth segment = EN.diff(en[i+1], en[i]);
470 if (segDirections[i] == Direction.RIGHT) {
471 h = EN.sum(h, segment);
472 } else if (segDirections[i] == Direction.UP) {
473 v = EN.sum(v, segment);
474 } else if (segDirections[i] == Direction.LEFT) {
475 h = EN.diff(h, segment);
476 } else if (segDirections[i] == Direction.DOWN) {
477 v = EN.diff(v, segment);
478 } else throw new IllegalStateException();
479 }
480 // rotate the vertical vector by 90 degrees (clockwise) and add it to the horizontal vector
481 segSum = EN.sum(h, new EastNorth(v.north(), -v.east()));
482 this.heading = EN.polar(new EastNorth(0., 0.), segSum);
483 }
484 }
485
486 private enum Direction {
487 RIGHT, UP, LEFT, DOWN;
488 public Direction changeBy(int directionChange) {
489 int tmp = (this.ordinal() + directionChange) % 4;
490 if (tmp < 0) {
491 tmp += 4; // the % operator can return negative value
492 }
493 return Direction.values()[tmp];
494 }
495 }
496
497 /**
498 * Make sure angle (up to 2*Pi) is in interval [ 0, 2*Pi ).
499 * @param a angle
500 * @return correct angle
501 */
502 private static double standard_angle_0_to_2PI(double a) {
503 while (a >= 2 * Math.PI) {
504 a -= 2 * Math.PI;
505 }
506 while (a < 0) {
507 a += 2 * Math.PI;
508 }
509 return a;
510 }
511
512 /**
513 * Make sure angle (up to 2*Pi) is in interval ( -Pi, Pi ].
514 * @param a angle
515 * @return correct angle
516 */
517 private static double standard_angle_mPI_to_PI(double a) {
518 while (a > Math.PI) {
519 a -= 2 * Math.PI;
520 }
521 while (a <= -Math.PI) {
522 a += 2 * Math.PI;
523 }
524 return a;
525 }
526
527 /**
528 * Class contains some auxiliary functions
529 */
530 private static final class EN {
531 private EN() {
532 // Hide implicit public constructor for utility class
533 }
534
535 /**
536 * Rotate counter-clock-wise.
537 * @param pivot pivot
538 * @param en original east/north
539 * @param angle angle, in radians
540 * @return new east/north
541 */
542 public static EastNorth rotateCC(EastNorth pivot, EastNorth en, double angle) {
543 double cosPhi = Math.cos(angle);
544 double sinPhi = Math.sin(angle);
545 double x = en.east() - pivot.east();
546 double y = en.north() - pivot.north();
547 double nx = cosPhi * x - sinPhi * y + pivot.east();
548 double ny = sinPhi * x + cosPhi * y + pivot.north();
549 return new EastNorth(nx, ny);
550 }
551
552 public static EastNorth sum(EastNorth en1, EastNorth en2) {
553 return new EastNorth(en1.east() + en2.east(), en1.north() + en2.north());
554 }
555
556 public static EastNorth diff(EastNorth en1, EastNorth en2) {
557 return new EastNorth(en1.east() - en2.east(), en1.north() - en2.north());
558 }
559
560 public static double polar(EastNorth en1, EastNorth en2) {
561 return Math.atan2(en2.north() - en1.north(), en2.east() - en1.east());
562 }
563 }
564
565 /**
566 * Recognize angle to be approximately 0, 90, 180 or 270 degrees.
567 * returns an integral value, corresponding to a counter clockwise turn.
568 * @param a angle, in radians
569 * @param deltaMax maximum tolerance, in radians
570 * @return an integral value, corresponding to a counter clockwise turn
571 * @throws RejectedAngleException in case of invalid angle
572 */
573 private static int angleToDirectionChange(double a, double deltaMax) throws RejectedAngleException {
574 a = standard_angle_mPI_to_PI(a);
575 double d0 = Math.abs(a);
576 double d90 = Math.abs(a - Math.PI / 2);
577 double dm90 = Math.abs(a + Math.PI / 2);
578 int dirChange;
579 if (d0 < deltaMax) {
580 dirChange = 0;
581 } else if (d90 < deltaMax) {
582 dirChange = 1;
583 } else if (dm90 < deltaMax) {
584 dirChange = -1;
585 } else {
586 a = standard_angle_0_to_2PI(a);
587 double d180 = Math.abs(a - Math.PI);
588 if (d180 < deltaMax) {
589 dirChange = 2;
590 } else
591 throw new RejectedAngleException();
592 }
593 return dirChange;
594 }
595
596 /**
597 * Exception: unsuited user input
598 */
599 protected static class InvalidUserInputException extends Exception {
600 InvalidUserInputException(String message) {
601 super(message);
602 }
603
604 InvalidUserInputException(String message, Throwable cause) {
605 super(message, cause);
606 }
607 }
608
609 /**
610 * Exception: angle cannot be recognized as 0, 90, 180 or 270 degrees
611 */
612 protected static class RejectedAngleException extends Exception {
613 RejectedAngleException() {
614 super();
615 }
616 }
617
618 @Override
619 protected void updateEnabledState() {
620 DataSet ds = getLayerManager().getEditDataSet();
621 setEnabled(ds != null && !ds.selectionEmpty());
622 }
623
624 @Override
625 protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) {
626 setEnabled(selection != null && !selection.isEmpty());
627 }
628}
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