source: josm/trunk/src/org/openstreetmap/josm/data/coor/LatLon.java@ 8846

Last change on this file since 8846 was 8846, checked in by Don-vip, 9 years ago

sonar - fb-contrib - minor performance improvements:

  • Method passes constant String of length 1 to character overridden method
  • Method needlessly boxes a boolean constant
  • Method uses iterator().next() on a List to get the first item
  • Method converts String to boxed primitive using excessive boxing
  • Method converts String to primitive using excessive boxing
  • Method creates array using constants
  • Class defines List based fields but uses them like Sets
  • Property svn:eol-style set to native
File size: 15.0 KB
Line 
1// License: GPL. For details, see LICENSE file.
2package org.openstreetmap.josm.data.coor;
3
4import static java.lang.Math.PI;
5import static java.lang.Math.asin;
6import static java.lang.Math.atan2;
7import static java.lang.Math.cos;
8import static java.lang.Math.sin;
9import static java.lang.Math.sqrt;
10import static java.lang.Math.toRadians;
11import static org.openstreetmap.josm.tools.I18n.trc;
12
13import java.awt.geom.Area;
14import java.text.DecimalFormat;
15import java.text.NumberFormat;
16import java.util.Arrays;
17import java.util.Locale;
18
19import org.openstreetmap.gui.jmapviewer.interfaces.ICoordinate;
20import org.openstreetmap.josm.Main;
21import org.openstreetmap.josm.data.Bounds;
22import org.openstreetmap.josm.tools.Utils;
23
24/**
25 * LatLon are unprojected latitude / longitude coordinates.
26 * <br>
27 * <b>Latitude</b> specifies the north-south position in degrees
28 * where valid values are in the [-90,90] and positive values specify positions north of the equator.
29 * <br>
30 * <b>Longitude</b> specifies the east-west position in degrees
31 * where valid values are in the [-180,180] and positive values specify positions east of the prime meridian.
32 * <br>
33 * <img alt="lat/lon" src="https://upload.wikimedia.org/wikipedia/commons/6/62/Latitude_and_Longitude_of_the_Earth.svg">
34 * <br>
35 * This class is immutable.
36 *
37 * @author Imi
38 */
39public class LatLon extends Coordinate {
40
41 private static final long serialVersionUID = 1L;
42
43 /**
44 * Minimum difference in location to not be represented as the same position.
45 * The API returns 7 decimals.
46 */
47 public static final double MAX_SERVER_PRECISION = 1e-7;
48 public static final double MAX_SERVER_INV_PRECISION = 1e7;
49 public static final int MAX_SERVER_DIGITS = 7;
50
51 /**
52 * The (0,0) coordinates.
53 * @since 6178
54 */
55 public static final LatLon ZERO = new LatLon(0, 0);
56
57 private static DecimalFormat cDmsMinuteFormatter = new DecimalFormat("00");
58 private static DecimalFormat cDmsSecondFormatter = new DecimalFormat("00.0");
59 private static DecimalFormat cDmMinuteFormatter = new DecimalFormat("00.000");
60 public static final DecimalFormat cDdFormatter;
61 public static final DecimalFormat cDdHighPecisionFormatter;
62 static {
63 // Don't use the localized decimal separator. This way we can present
64 // a comma separated list of coordinates.
65 cDdFormatter = (DecimalFormat) NumberFormat.getInstance(Locale.UK);
66 cDdFormatter.applyPattern("###0.0######");
67 cDdHighPecisionFormatter = (DecimalFormat) NumberFormat.getInstance(Locale.UK);
68 cDdHighPecisionFormatter.applyPattern("###0.0##########");
69 }
70
71 private static final String cDms60 = cDmsSecondFormatter.format(60.0);
72 private static final String cDms00 = cDmsSecondFormatter.format(0.0);
73 private static final String cDm60 = cDmMinuteFormatter.format(60.0);
74 private static final String cDm00 = cDmMinuteFormatter.format(0.0);
75
76 /**
77 * Replies true if lat is in the range [-90,90]
78 *
79 * @param lat the latitude
80 * @return true if lat is in the range [-90,90]
81 */
82 public static boolean isValidLat(double lat) {
83 return lat >= -90d && lat <= 90d;
84 }
85
86 /**
87 * Replies true if lon is in the range [-180,180]
88 *
89 * @param lon the longitude
90 * @return true if lon is in the range [-180,180]
91 */
92 public static boolean isValidLon(double lon) {
93 return lon >= -180d && lon <= 180d;
94 }
95
96 /**
97 * Replies true if lat is in the range [-90,90] and lon is in the range [-180,180]
98 *
99 * @return true if lat is in the range [-90,90] and lon is in the range [-180,180]
100 */
101 public boolean isValid() {
102 return isValidLat(lat()) && isValidLon(lon());
103 }
104
105 public static double toIntervalLat(double value) {
106 if (value < -90)
107 return -90;
108 if (value > 90)
109 return 90;
110 return value;
111 }
112
113 /**
114 * Returns a valid OSM longitude [-180,+180] for the given extended longitude value.
115 * For example, a value of -181 will return +179, a value of +181 will return -179.
116 * @param value A longitude value not restricted to the [-180,+180] range.
117 */
118 public static double toIntervalLon(double value) {
119 if (isValidLon(value))
120 return value;
121 else {
122 int n = (int) (value + Math.signum(value)*180.0) / 360;
123 return value - n*360.0;
124 }
125 }
126
127 /**
128 * Replies the coordinate in degrees/minutes/seconds format
129 * @param pCoordinate The coordinate to convert
130 * @return The coordinate in degrees/minutes/seconds format
131 */
132 public static String dms(double pCoordinate) {
133
134 double tAbsCoord = Math.abs(pCoordinate);
135 int tDegree = (int) tAbsCoord;
136 double tTmpMinutes = (tAbsCoord - tDegree) * 60;
137 int tMinutes = (int) tTmpMinutes;
138 double tSeconds = (tTmpMinutes - tMinutes) * 60;
139
140 String sDegrees = Integer.toString(tDegree);
141 String sMinutes = cDmsMinuteFormatter.format(tMinutes);
142 String sSeconds = cDmsSecondFormatter.format(tSeconds);
143
144 if (cDms60.equals(sSeconds)) {
145 sSeconds = cDms00;
146 sMinutes = cDmsMinuteFormatter.format(tMinutes+1);
147 }
148 if ("60".equals(sMinutes)) {
149 sMinutes = "00";
150 sDegrees = Integer.toString(tDegree+1);
151 }
152
153 return sDegrees + '\u00B0' + sMinutes + '\'' + sSeconds + '\"';
154 }
155
156 /**
157 * Replies the coordinate in degrees/minutes format
158 * @param pCoordinate The coordinate to convert
159 * @return The coordinate in degrees/minutes format
160 */
161 public static String dm(double pCoordinate) {
162
163 double tAbsCoord = Math.abs(pCoordinate);
164 int tDegree = (int) tAbsCoord;
165 double tMinutes = (tAbsCoord - tDegree) * 60;
166
167 String sDegrees = Integer.toString(tDegree);
168 String sMinutes = cDmMinuteFormatter.format(tMinutes);
169
170 if (sMinutes.equals(cDm60)) {
171 sMinutes = cDm00;
172 sDegrees = Integer.toString(tDegree+1);
173 }
174
175 return sDegrees + '\u00B0' + sMinutes + '\'';
176 }
177
178 /**
179 * Constructs a new {@link LatLon}
180 * @param lat the latitude, i.e., the north-south position in degrees
181 * @param lon the longitude, i.e., the east-west position in degrees
182 */
183 public LatLon(double lat, double lon) {
184 super(lon, lat);
185 }
186
187 protected LatLon(LatLon coor) {
188 super(coor.lon(), coor.lat());
189 }
190
191 public LatLon(ICoordinate coor) {
192 this(coor.getLat(), coor.getLon());
193 }
194
195
196 /**
197 * Returns the latitude, i.e., the north-south position in degrees.
198 * @return the latitude
199 */
200 public double lat() {
201 return y;
202 }
203
204 public static final String SOUTH = trc("compass", "S");
205 public static final String NORTH = trc("compass", "N");
206
207 public String latToString(CoordinateFormat d) {
208 switch(d) {
209 case DECIMAL_DEGREES: return cDdFormatter.format(y);
210 case DEGREES_MINUTES_SECONDS: return dms(y) + ((y < 0) ? SOUTH : NORTH);
211 case NAUTICAL: return dm(y) + ((y < 0) ? SOUTH : NORTH);
212 case EAST_NORTH: return cDdFormatter.format(Main.getProjection().latlon2eastNorth(this).north());
213 default: return "ERR";
214 }
215 }
216
217 /**
218 * Returns the longitude, i.e., the east-west position in degrees.
219 * @return the longitude
220 */
221 public double lon() {
222 return x;
223 }
224
225 public static final String WEST = trc("compass", "W");
226 public static final String EAST = trc("compass", "E");
227
228 public String lonToString(CoordinateFormat d) {
229 switch(d) {
230 case DECIMAL_DEGREES: return cDdFormatter.format(x);
231 case DEGREES_MINUTES_SECONDS: return dms(x) + ((x < 0) ? WEST : EAST);
232 case NAUTICAL: return dm(x) + ((x < 0) ? WEST : EAST);
233 case EAST_NORTH: return cDdFormatter.format(Main.getProjection().latlon2eastNorth(this).east());
234 default: return "ERR";
235 }
236 }
237
238 /**
239 * @return <code>true</code> if the other point has almost the same lat/lon
240 * values, only differing by no more than
241 * 1 / {@link #MAX_SERVER_PRECISION MAX_SERVER_PRECISION}.
242 */
243 public boolean equalsEpsilon(LatLon other) {
244 double p = MAX_SERVER_PRECISION / 2;
245 return Math.abs(lat()-other.lat()) <= p && Math.abs(lon()-other.lon()) <= p;
246 }
247
248 /**
249 * @return <code>true</code>, if the coordinate is outside the world, compared
250 * by using lat/lon.
251 */
252 public boolean isOutSideWorld() {
253 Bounds b = Main.getProjection().getWorldBoundsLatLon();
254 return lat() < b.getMinLat() || lat() > b.getMaxLat() ||
255 lon() < b.getMinLon() || lon() > b.getMaxLon();
256 }
257
258 /**
259 * @return <code>true</code> if this is within the given bounding box.
260 */
261 public boolean isWithin(Bounds b) {
262 return b.contains(this);
263 }
264
265 /**
266 * Check if this is contained in given area or area is null.
267 *
268 * @param a Area
269 * @return <code>true</code> if this is contained in given area or area is null.
270 */
271 public boolean isIn(Area a) {
272 return a == null || a.contains(x, y);
273 }
274
275 /**
276 * Computes the distance between this lat/lon and another point on the earth.
277 * Uses Haversine formular.
278 * @param other the other point.
279 * @return distance in metres.
280 */
281 public double greatCircleDistance(LatLon other) {
282 double R = 6378135;
283 double sinHalfLat = sin(toRadians(other.lat() - this.lat()) / 2);
284 double sinHalfLon = sin(toRadians(other.lon() - this.lon()) / 2);
285 double d = 2 * R * asin(
286 sqrt(sinHalfLat*sinHalfLat +
287 cos(toRadians(this.lat()))*cos(toRadians(other.lat()))*sinHalfLon*sinHalfLon));
288 // For points opposite to each other on the sphere,
289 // rounding errors could make the argument of asin greater than 1
290 // (This should almost never happen.)
291 if (java.lang.Double.isNaN(d)) {
292 Main.error("NaN in greatCircleDistance");
293 d = PI * R;
294 }
295 return d;
296 }
297
298 /**
299 * Returns the heading, in radians, that you have to use to get from this lat/lon to another.
300 *
301 * (I don't know the original source of this formula, but see
302 * <a href="https://math.stackexchange.com/questions/720/how-to-calculate-a-heading-on-the-earths-surface">this question</a>
303 * for some hints how it is derived.)
304 *
305 * @param other the "destination" position
306 * @return heading in the range 0 &lt;= hd &lt; 2*PI
307 */
308 public double heading(LatLon other) {
309 double hd = atan2(sin(toRadians(this.lon() - other.lon())) * cos(toRadians(other.lat())),
310 cos(toRadians(this.lat())) * sin(toRadians(other.lat())) -
311 sin(toRadians(this.lat())) * cos(toRadians(other.lat())) * cos(toRadians(this.lon() - other.lon())));
312 hd %= 2 * PI;
313 if (hd < 0) {
314 hd += 2 * PI;
315 }
316 return hd;
317 }
318
319 /**
320 * Returns this lat/lon pair in human-readable format.
321 *
322 * @return String in the format "lat=1.23456 deg, lon=2.34567 deg"
323 */
324 public String toDisplayString() {
325 NumberFormat nf = NumberFormat.getInstance();
326 nf.setMaximumFractionDigits(5);
327 return "lat=" + nf.format(lat()) + "\u00B0, lon=" + nf.format(lon()) + '\u00B0';
328 }
329
330 /**
331 * Returns this lat/lon pair in human-readable format separated by {@code separator}.
332 * @return String in the format {@code "1.23456[separator]2.34567"}
333 */
334 public String toStringCSV(String separator) {
335 return Utils.join(separator, Arrays.asList(
336 latToString(CoordinateFormat.DECIMAL_DEGREES),
337 lonToString(CoordinateFormat.DECIMAL_DEGREES)
338 ));
339 }
340
341 public LatLon interpolate(LatLon ll2, double proportion) {
342 return new LatLon(this.lat() + proportion * (ll2.lat() - this.lat()),
343 this.lon() + proportion * (ll2.lon() - this.lon()));
344 }
345
346 public LatLon getCenter(LatLon ll2) {
347 return new LatLon((this.lat() + ll2.lat())/2.0, (this.lon() + ll2.lon())/2.0);
348 }
349
350 /**
351 * Returns the euclidean distance from this {@code LatLon} to a specified {@code LatLon}.
352 *
353 * @param ll the specified coordinate to be measured against this {@code LatLon}
354 * @return the euclidean distance from this {@code LatLon} to a specified {@code LatLon}
355 * @since 6166
356 */
357 public double distance(final LatLon ll) {
358 return super.distance(ll);
359 }
360
361 /**
362 * Returns the square of the euclidean distance from this {@code LatLon} to a specified {@code LatLon}.
363 *
364 * @param ll the specified coordinate to be measured against this {@code LatLon}
365 * @return the square of the euclidean distance from this {@code LatLon} to a specified {@code LatLon}
366 * @since 6166
367 */
368 public double distanceSq(final LatLon ll) {
369 return super.distanceSq(ll);
370 }
371
372 @Override
373 public String toString() {
374 return "LatLon[lat="+lat()+",lon="+lon()+']';
375 }
376
377 /**
378 * Returns the value rounded to OSM precisions, i.e. to
379 * LatLon.MAX_SERVER_PRECISION
380 *
381 * @return rounded value
382 */
383 public static double roundToOsmPrecision(double value) {
384 return Math.round(value * MAX_SERVER_INV_PRECISION) / MAX_SERVER_INV_PRECISION;
385 }
386
387 /**
388 * Returns the value rounded to OSM precision. This function is now the same as
389 * {@link #roundToOsmPrecision(double)}, since the rounding error has been fixed.
390 *
391 * @return rounded value
392 */
393 public static double roundToOsmPrecisionStrict(double value) {
394 return roundToOsmPrecision(value);
395 }
396
397 /**
398 * Replies a clone of this lat LatLon, rounded to OSM precisions, i.e. to
399 * MAX_SERVER_PRECISION
400 *
401 * @return a clone of this lat LatLon
402 */
403 public LatLon getRoundedToOsmPrecision() {
404 return new LatLon(
405 roundToOsmPrecision(lat()),
406 roundToOsmPrecision(lon())
407 );
408 }
409
410 /**
411 * Replies a clone of this lat LatLon, rounded to OSM precisions, i.e. to
412 * MAX_SERVER_PRECISION
413 *
414 * @return a clone of this lat LatLon
415 */
416 public LatLon getRoundedToOsmPrecisionStrict() {
417 return new LatLon(
418 roundToOsmPrecisionStrict(lat()),
419 roundToOsmPrecisionStrict(lon())
420 );
421 }
422
423 @Override
424 public int hashCode() {
425 return computeHashCode(super.hashCode());
426 }
427
428 @Override
429 public boolean equals(Object obj) {
430 if (this == obj)
431 return true;
432 if (!super.equals(obj))
433 return false;
434 if (getClass() != obj.getClass())
435 return false;
436 Coordinate other = (Coordinate) obj;
437 if (java.lang.Double.doubleToLongBits(x) != java.lang.Double.doubleToLongBits(other.x))
438 return false;
439 if (java.lang.Double.doubleToLongBits(y) != java.lang.Double.doubleToLongBits(other.y))
440 return false;
441 return true;
442 }
443
444 public ICoordinate toCoordinate() {
445 return new org.openstreetmap.gui.jmapviewer.Coordinate(lat(), lon());
446 }
447}
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