source: josm/trunk/src/org/openstreetmap/josm/data/coor/LatLon.java@ 8126

Last change on this file since 8126 was 7236, checked in by bastiK, 10 years ago

fixed #10115 - increase number of digits saved to file
  • Property svn:eol-style set to native
File size: 14.7 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.josm.Main;
20import org.openstreetmap.josm.data.Bounds;
21import org.openstreetmap.josm.tools.Utils;
22
23/**
24 * LatLon are unprojected latitude / longitude coordinates.
25 * <br>
26 * <b>Latitude</b> specifies the north-south position in degrees
27 * where valid values are in the [-90,90] and positive values specify positions north of the equator.
28 * <br>
29 * <b>Longitude</b> specifies the east-west position in degrees
30 * where valid values are in the [-180,180] and positive values specify positions east of the prime meridian.
31 * <br>
32 * <img alt="lat/lon" src="https://upload.wikimedia.org/wikipedia/commons/thumb/6/62/Latitude_and_Longitude_of_the_Earth.svg/500px-Latitude_and_Longitude_of_the_Earth.svg.png">
33 * <br>
34 * This class is immutable.
35 *
36 * @author Imi
37 */
38public class LatLon extends Coordinate {
39
40 /**
41 * Minimum difference in location to not be represented as the same position.
42 * The API returns 7 decimals.
43 */
44 public static final double MAX_SERVER_PRECISION = 1e-7;
45 public static final double MAX_SERVER_INV_PRECISION = 1e7;
46 public static final int MAX_SERVER_DIGITS = 7;
47
48 /**
49 * The (0,0) coordinates.
50 * @since 6178
51 */
52 public static final LatLon ZERO = new LatLon(0, 0);
53
54 private static DecimalFormat cDmsMinuteFormatter = new DecimalFormat("00");
55 private static DecimalFormat cDmsSecondFormatter = new DecimalFormat("00.0");
56 private static DecimalFormat cDmMinuteFormatter = new DecimalFormat("00.000");
57 public static final DecimalFormat cDdFormatter;
58 public static final DecimalFormat cDdHighPecisionFormatter;
59 static {
60 // Don't use the localized decimal separator. This way we can present
61 // a comma separated list of coordinates.
62 cDdFormatter = (DecimalFormat) NumberFormat.getInstance(Locale.UK);
63 cDdFormatter.applyPattern("###0.0######");
64 cDdHighPecisionFormatter = (DecimalFormat) NumberFormat.getInstance(Locale.UK);
65 cDdHighPecisionFormatter.applyPattern("###0.0##########");
66 }
67
68 private static final String cDms60 = cDmsSecondFormatter.format(60.0);
69 private static final String cDms00 = cDmsSecondFormatter.format( 0.0);
70 private static final String cDm60 = cDmMinuteFormatter.format(60.0);
71 private static final String cDm00 = cDmMinuteFormatter.format( 0.0);
72
73 /**
74 * Replies true if lat is in the range [-90,90]
75 *
76 * @param lat the latitude
77 * @return true if lat is in the range [-90,90]
78 */
79 public static boolean isValidLat(double lat) {
80 return lat >= -90d && lat <= 90d;
81 }
82
83 /**
84 * Replies true if lon is in the range [-180,180]
85 *
86 * @param lon the longitude
87 * @return true if lon is in the range [-180,180]
88 */
89 public static boolean isValidLon(double lon) {
90 return lon >= -180d && lon <= 180d;
91 }
92
93 /**
94 * Replies true if lat is in the range [-90,90] and lon is in the range [-180,180]
95 *
96 * @return true if lat is in the range [-90,90] and lon is in the range [-180,180]
97 */
98 public boolean isValid() {
99 return isValidLat(lat()) && isValidLon(lon());
100 }
101
102 public static double toIntervalLat(double value) {
103 if (value < -90)
104 return -90;
105 if (value > 90)
106 return 90;
107 return value;
108 }
109
110 /**
111 * Returns a valid OSM longitude [-180,+180] for the given extended longitude value.
112 * For example, a value of -181 will return +179, a value of +181 will return -179.
113 * @param value A longitude value not restricted to the [-180,+180] range.
114 */
115 public static double toIntervalLon(double value) {
116 if (isValidLon(value))
117 return value;
118 else {
119 int n = (int) (value + Math.signum(value)*180.0) / 360;
120 return value - n*360.0;
121 }
122 }
123
124 /**
125 * Replies the coordinate in degrees/minutes/seconds format
126 * @param pCoordinate The coordinate to convert
127 * @return The coordinate in degrees/minutes/seconds format
128 */
129 public static String dms(double pCoordinate) {
130
131 double tAbsCoord = Math.abs(pCoordinate);
132 int tDegree = (int) tAbsCoord;
133 double tTmpMinutes = (tAbsCoord - tDegree) * 60;
134 int tMinutes = (int) tTmpMinutes;
135 double tSeconds = (tTmpMinutes - tMinutes) * 60;
136
137 String sDegrees = Integer.toString(tDegree);
138 String sMinutes = cDmsMinuteFormatter.format(tMinutes);
139 String sSeconds = cDmsSecondFormatter.format(tSeconds);
140
141 if (cDms60.equals(sSeconds)) {
142 sSeconds = cDms00;
143 sMinutes = cDmsMinuteFormatter.format(tMinutes+1);
144 }
145 if ("60".equals(sMinutes)) {
146 sMinutes = "00";
147 sDegrees = Integer.toString(tDegree+1);
148 }
149
150 return sDegrees + "\u00B0" + sMinutes + "\'" + sSeconds + "\"";
151 }
152
153 /**
154 * Replies the coordinate in degrees/minutes format
155 * @param pCoordinate The coordinate to convert
156 * @return The coordinate in degrees/minutes format
157 */
158 public static String dm(double pCoordinate) {
159
160 double tAbsCoord = Math.abs(pCoordinate);
161 int tDegree = (int) tAbsCoord;
162 double tMinutes = (tAbsCoord - tDegree) * 60;
163
164 String sDegrees = Integer.toString(tDegree);
165 String sMinutes = cDmMinuteFormatter.format(tMinutes);
166
167 if (sMinutes.equals(cDm60)) {
168 sMinutes = cDm00;
169 sDegrees = Integer.toString(tDegree+1);
170 }
171
172 return sDegrees + "\u00B0" + sMinutes + "\'";
173 }
174
175 /**
176 * Constructs a new {@link LatLon}
177 * @param lat the latitude, i.e., the north-south position in degrees
178 * @param lon the longitude, i.e., the east-west position in degrees
179 */
180 public LatLon(double lat, double lon) {
181 super(lon, lat);
182 }
183
184 protected LatLon(LatLon coor) {
185 super(coor.lon(), coor.lat());
186 }
187
188 /**
189 * Returns the latitude, i.e., the north-south position in degrees.
190 * @return the latitude
191 */
192 public double lat() {
193 return y;
194 }
195
196 public static final String SOUTH = trc("compass", "S");
197 public static final String NORTH = trc("compass", "N");
198 public String latToString(CoordinateFormat d) {
199 switch(d) {
200 case DECIMAL_DEGREES: return cDdFormatter.format(y);
201 case DEGREES_MINUTES_SECONDS: return dms(y) + ((y < 0) ? SOUTH : NORTH);
202 case NAUTICAL: return dm(y) + ((y < 0) ? SOUTH : NORTH);
203 case EAST_NORTH: return cDdFormatter.format(Main.getProjection().latlon2eastNorth(this).north());
204 default: return "ERR";
205 }
206 }
207
208 /**
209 * Returns the longitude, i.e., the east-west position in degrees.
210 * @return the longitude
211 */
212 public double lon() {
213 return x;
214 }
215
216 public static final String WEST = trc("compass", "W");
217 public static final String EAST = trc("compass", "E");
218 public String lonToString(CoordinateFormat d) {
219 switch(d) {
220 case DECIMAL_DEGREES: return cDdFormatter.format(x);
221 case DEGREES_MINUTES_SECONDS: return dms(x) + ((x < 0) ? WEST : EAST);
222 case NAUTICAL: return dm(x) + ((x < 0) ? WEST : EAST);
223 case EAST_NORTH: return cDdFormatter.format(Main.getProjection().latlon2eastNorth(this).east());
224 default: return "ERR";
225 }
226 }
227
228 /**
229 * @return <code>true</code> if the other point has almost the same lat/lon
230 * values, only differing by no more than
231 * 1 / {@link #MAX_SERVER_PRECISION MAX_SERVER_PRECISION}.
232 */
233 public boolean equalsEpsilon(LatLon other) {
234 double p = MAX_SERVER_PRECISION / 2;
235 return Math.abs(lat()-other.lat()) <= p && Math.abs(lon()-other.lon()) <= p;
236 }
237
238 /**
239 * @return <code>true</code>, if the coordinate is outside the world, compared
240 * by using lat/lon.
241 */
242 public boolean isOutSideWorld() {
243 Bounds b = Main.getProjection().getWorldBoundsLatLon();
244 return lat() < b.getMinLat() || lat() > b.getMaxLat() ||
245 lon() < b.getMinLon() || lon() > b.getMaxLon();
246 }
247
248 /**
249 * @return <code>true</code> if this is within the given bounding box.
250 */
251 public boolean isWithin(Bounds b) {
252 return b.contains(this);
253 }
254
255 /**
256 * Check if this is contained in given area or area is null.
257 *
258 * @param a Area
259 * @return <code>true</code> if this is contained in given area or area is null.
260 */
261 public boolean isIn(Area a) {
262 return a == null || a.contains(x, y);
263 }
264
265 /**
266 * Computes the distance between this lat/lon and another point on the earth.
267 * Uses Haversine formular.
268 * @param other the other point.
269 * @return distance in metres.
270 */
271 public double greatCircleDistance(LatLon other) {
272 double R = 6378135;
273 double sinHalfLat = sin(toRadians(other.lat() - this.lat()) / 2);
274 double sinHalfLon = sin(toRadians(other.lon() - this.lon()) / 2);
275 double d = 2 * R * asin(
276 sqrt(sinHalfLat*sinHalfLat +
277 cos(toRadians(this.lat()))*cos(toRadians(other.lat()))*sinHalfLon*sinHalfLon));
278 // For points opposite to each other on the sphere,
279 // rounding errors could make the argument of asin greater than 1
280 // (This should almost never happen.)
281 if (java.lang.Double.isNaN(d)) {
282 Main.error("NaN in greatCircleDistance");
283 d = PI * R;
284 }
285 return d;
286 }
287
288 /**
289 * Returns the heading, in radians, that you have to use to get from this lat/lon to another.
290 *
291 * (I don't know the original source of this formula, but see
292 * <a href="https://math.stackexchange.com/questions/720/how-to-calculate-a-heading-on-the-earths-surface">this question</a>
293 * for some hints how it is derived.)
294 *
295 * @param other the "destination" position
296 * @return heading in the range 0 &lt;= hd &lt; 2*PI
297 */
298 public double heading(LatLon other) {
299 double hd = atan2(sin(toRadians(this.lon() - other.lon())) * cos(toRadians(other.lat())),
300 cos(toRadians(this.lat())) * sin(toRadians(other.lat())) -
301 sin(toRadians(this.lat())) * cos(toRadians(other.lat())) * cos(toRadians(this.lon() - other.lon())));
302 hd %= 2 * PI;
303 if (hd < 0) {
304 hd += 2 * PI;
305 }
306 return hd;
307 }
308
309 /**
310 * Returns this lat/lon pair in human-readable format.
311 *
312 * @return String in the format "lat=1.23456 deg, lon=2.34567 deg"
313 */
314 public String toDisplayString() {
315 NumberFormat nf = NumberFormat.getInstance();
316 nf.setMaximumFractionDigits(5);
317 return "lat=" + nf.format(lat()) + "\u00B0, lon=" + nf.format(lon()) + "\u00B0";
318 }
319
320 /**
321 * Returns this lat/lon pair in human-readable format separated by {@code separator}.
322 * @return String in the format {@code "1.23456[separator]2.34567"}
323 */
324 public String toStringCSV(String separator) {
325 return Utils.join(separator, Arrays.asList(
326 latToString(CoordinateFormat.DECIMAL_DEGREES),
327 lonToString(CoordinateFormat.DECIMAL_DEGREES)
328 ));
329 }
330
331 public LatLon interpolate(LatLon ll2, double proportion) {
332 return new LatLon(this.lat() + proportion * (ll2.lat() - this.lat()),
333 this.lon() + proportion * (ll2.lon() - this.lon()));
334 }
335
336 public LatLon getCenter(LatLon ll2) {
337 return new LatLon((this.lat() + ll2.lat())/2.0, (this.lon() + ll2.lon())/2.0);
338 }
339
340 /**
341 * Returns the euclidean distance from this {@code LatLon} to a specified {@code LatLon}.
342 *
343 * @param ll the specified coordinate to be measured against this {@code LatLon}
344 * @return the euclidean distance from this {@code LatLon} to a specified {@code LatLon}
345 * @since 6166
346 */
347 public double distance(final LatLon ll) {
348 return super.distance(ll);
349 }
350
351 /**
352 * Returns the square of the euclidean distance from this {@code LatLon} to a specified {@code LatLon}.
353 *
354 * @param ll the specified coordinate to be measured against this {@code LatLon}
355 * @return the square of the euclidean distance from this {@code LatLon} to a specified {@code LatLon}
356 * @since 6166
357 */
358 public double distanceSq(final LatLon ll) {
359 return super.distanceSq(ll);
360 }
361
362 @Override public String toString() {
363 return "LatLon[lat="+lat()+",lon="+lon()+"]";
364 }
365
366 /**
367 * Returns the value rounded to OSM precisions, i.e. to
368 * LatLon.MAX_SERVER_PRECISION
369 *
370 * @return rounded value
371 */
372 public static double roundToOsmPrecision(double value) {
373 return Math.round(value * MAX_SERVER_INV_PRECISION) / MAX_SERVER_INV_PRECISION;
374 }
375
376 /**
377 * Returns the value rounded to OSM precision. This function is now the same as
378 * {@link #roundToOsmPrecision(double)}, since the rounding error has been fixed.
379 *
380 * @return rounded value
381 */
382 public static double roundToOsmPrecisionStrict(double value) {
383 return roundToOsmPrecision(value);
384 }
385
386 /**
387 * Replies a clone of this lat LatLon, rounded to OSM precisions, i.e. to
388 * MAX_SERVER_PRECISION
389 *
390 * @return a clone of this lat LatLon
391 */
392 public LatLon getRoundedToOsmPrecision() {
393 return new LatLon(
394 roundToOsmPrecision(lat()),
395 roundToOsmPrecision(lon())
396 );
397 }
398
399 /**
400 * Replies a clone of this lat LatLon, rounded to OSM precisions, i.e. to
401 * MAX_SERVER_PRECISION
402 *
403 * @return a clone of this lat LatLon
404 */
405 public LatLon getRoundedToOsmPrecisionStrict() {
406 return new LatLon(
407 roundToOsmPrecisionStrict(lat()),
408 roundToOsmPrecisionStrict(lon())
409 );
410 }
411
412 @Override
413 public int hashCode() {
414 return computeHashCode(super.hashCode());
415 }
416
417 @Override
418 public boolean equals(Object obj) {
419 if (this == obj)
420 return true;
421 if (!super.equals(obj))
422 return false;
423 if (getClass() != obj.getClass())
424 return false;
425 Coordinate other = (Coordinate) obj;
426 if (java.lang.Double.doubleToLongBits(x) != java.lang.Double.doubleToLongBits(other.x))
427 return false;
428 if (java.lang.Double.doubleToLongBits(y) != java.lang.Double.doubleToLongBits(other.y))
429 return false;
430 return true;
431 }
432}
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