source: josm/trunk/src/org/openstreetmap/josm/data/coor/LatLon.java@ 5474

Last change on this file since 5474 was 5474, checked in by Don-vip, 12 years ago

fix #7994 - WGS84-DMS-ordinates are shown as 01'60,0" instead of 02'00,0"
  • Property svn:eol-style set to native
File size: 11.9 KB
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1// License: GPL. Copyright 2007 by Immanuel Scholz and others
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.text.DecimalFormat;
14import java.text.NumberFormat;
15import java.util.Locale;
16
17import org.openstreetmap.josm.Main;
18import org.openstreetmap.josm.data.Bounds;
19
20/**
21 * LatLon are unprojected latitude / longitude coordinates.
22 *
23 * This class is immutable.
24 *
25 * @author Imi
26 */
27public class LatLon extends Coordinate {
28
29
30 /**
31 * Minimum difference in location to not be represented as the same position.
32 * The API returns 7 decimals.
33 */
34 public static final double MAX_SERVER_PRECISION = 1e-7;
35 public static final double MAX_SERVER_INV_PRECISION = 1e7;
36 public static final int MAX_SERVER_DIGITS = 7;
37
38 private static DecimalFormat cDmsMinuteFormatter = new DecimalFormat("00");
39 private static DecimalFormat cDmsSecondFormatter = new DecimalFormat("00.0");
40 private static DecimalFormat cDmMinuteFormatter = new DecimalFormat("00.000");
41 public static final DecimalFormat cDdFormatter;
42 static {
43 // Don't use the localized decimal separator. This way we can present
44 // a comma separated list of coordinates.
45 cDdFormatter = (DecimalFormat) NumberFormat.getInstance(Locale.UK);
46 cDdFormatter.applyPattern("###0.0######");
47 }
48
49 /**
50 * Replies true if lat is in the range [-90,90]
51 *
52 * @param lat the latitude
53 * @return true if lat is in the range [-90,90]
54 */
55 public static boolean isValidLat(double lat) {
56 return lat >= -90d && lat <= 90d;
57 }
58
59 /**
60 * Replies true if lon is in the range [-180,180]
61 *
62 * @param lon the longitude
63 * @return true if lon is in the range [-180,180]
64 */
65 public static boolean isValidLon(double lon) {
66 return lon >= -180d && lon <= 180d;
67 }
68
69 /**
70 * Replies true if lat is in the range [-90,90] and lon is in the range [-180,180]
71 *
72 * @return true if lat is in the range [-90,90] and lon is in the range [-180,180]
73 */
74 public boolean isValid() {
75 return isValidLat(lat()) && isValidLon(lon());
76 }
77
78 public static double toIntervalLat(double value) {
79 if (value < -90)
80 return -90;
81 if (value > 90)
82 return 90;
83 return value;
84 }
85
86 /**
87 * Returns a valid OSM longitude [-180,+180] for the given extended longitude value.
88 * For example, a value of -181 will return +179, a value of +181 will return -179.
89 * @param lon A longitude value not restricted to the [-180,+180] range.
90 */
91 public static double toIntervalLon(double value) {
92 if (isValidLon(value))
93 return value;
94 else {
95 int n = (int) (value + Math.signum(value)*180.0) / 360;
96 return value - n*360.0;
97 }
98 }
99
100 /**
101 * Replies the coordinate in degrees/minutes/seconds format
102 * @param pCoordinate The coordinate to convert
103 * @return The coordinate in degrees/minutes/seconds format
104 */
105 public static String dms(double pCoordinate) {
106
107 double tAbsCoord = Math.abs(pCoordinate);
108 int tDegree = (int) tAbsCoord;
109 double tTmpMinutes = (tAbsCoord - tDegree) * 60;
110 int tMinutes = (int) tTmpMinutes;
111 double tSeconds = (tTmpMinutes - tMinutes) * 60;
112
113 String sDegrees = Integer.toString(tDegree);
114 String sMinutes = cDmsMinuteFormatter.format(tMinutes);
115 String sSeconds = cDmsSecondFormatter.format(tSeconds);
116
117 if (sSeconds.equals("60.0")) {
118 sSeconds = "00.0";
119 sMinutes = cDmsMinuteFormatter.format(tMinutes+1);
120 }
121 if (sMinutes.equals("60")) {
122 sMinutes = "00";
123 sDegrees = Integer.toString(tDegree+1);
124 }
125
126 return sDegrees + "\u00B0" + sMinutes + "\'" + sSeconds + "\"";
127 }
128
129 /**
130 * Replies the coordinate in degrees/minutes format
131 * @param pCoordinate The coordinate to convert
132 * @return The coordinate in degrees/minutes format
133 */
134 public static String dm(double pCoordinate) {
135
136 double tAbsCoord = Math.abs(pCoordinate);
137 int tDegree = (int) tAbsCoord;
138 double tMinutes = (tAbsCoord - tDegree) * 60;
139
140 String sDegrees = Integer.toString(tDegree);
141 String sMinutes = cDmMinuteFormatter.format(tMinutes);
142
143 if (sMinutes.equals("60.000")) {
144 sMinutes = "00.000";
145 sDegrees = Integer.toString(tDegree+1);
146 }
147
148 return sDegrees + "\u00B0" + sMinutes + "\'";
149 }
150
151 public LatLon(double lat, double lon) {
152 super(lon, lat);
153 }
154
155 public LatLon(LatLon coor) {
156 super(coor.lon(), coor.lat());
157 }
158
159 public double lat() {
160 return y;
161 }
162
163 public final static String SOUTH = trc("compass", "S");
164 public final static String NORTH = trc("compass", "N");
165 public String latToString(CoordinateFormat d) {
166 switch(d) {
167 case DECIMAL_DEGREES: return cDdFormatter.format(y);
168 case DEGREES_MINUTES_SECONDS: return dms(y) + ((y < 0) ? SOUTH : NORTH);
169 case NAUTICAL: return dm(y) + ((y < 0) ? SOUTH : NORTH);
170 case EAST_NORTH: return cDdFormatter.format(Main.getProjection().latlon2eastNorth(this).north());
171 default: return "ERR";
172 }
173 }
174
175 public double lon() {
176 return x;
177 }
178
179 public final static String WEST = trc("compass", "W");
180 public final static String EAST = trc("compass", "E");
181 public String lonToString(CoordinateFormat d) {
182 switch(d) {
183 case DECIMAL_DEGREES: return cDdFormatter.format(x);
184 case DEGREES_MINUTES_SECONDS: return dms(x) + ((x < 0) ? WEST : EAST);
185 case NAUTICAL: return dm(x) + ((x < 0) ? WEST : EAST);
186 case EAST_NORTH: return cDdFormatter.format(Main.getProjection().latlon2eastNorth(this).east());
187 default: return "ERR";
188 }
189 }
190
191 /**
192 * @return <code>true</code> if the other point has almost the same lat/lon
193 * values, only differing by no more than
194 * 1 / {@link #MAX_SERVER_PRECISION MAX_SERVER_PRECISION}.
195 */
196 public boolean equalsEpsilon(LatLon other) {
197 double p = MAX_SERVER_PRECISION / 2;
198 return Math.abs(lat()-other.lat()) <= p && Math.abs(lon()-other.lon()) <= p;
199 }
200
201 /**
202 * @return <code>true</code>, if the coordinate is outside the world, compared
203 * by using lat/lon.
204 */
205 public boolean isOutSideWorld() {
206 Bounds b = Main.getProjection().getWorldBoundsLatLon();
207 return lat() < b.getMin().lat() || lat() > b.getMax().lat() ||
208 lon() < b.getMin().lon() || lon() > b.getMax().lon();
209 }
210
211 /**
212 * @return <code>true</code> if this is within the given bounding box.
213 */
214 public boolean isWithin(Bounds b) {
215 return b.contains(this);
216 }
217
218 /**
219 * Computes the distance between this lat/lon and another point on the earth.
220 * Uses Haversine formular.
221 * @param other the other point.
222 * @return distance in metres.
223 */
224 public double greatCircleDistance(LatLon other) {
225 double R = 6378135;
226 double sinHalfLat = sin(toRadians(other.lat() - this.lat()) / 2);
227 double sinHalfLon = sin(toRadians(other.lon() - this.lon()) / 2);
228 double d = 2 * R * asin(
229 sqrt(sinHalfLat*sinHalfLat +
230 cos(toRadians(this.lat()))*cos(toRadians(other.lat()))*sinHalfLon*sinHalfLon));
231 // For points opposite to each other on the sphere,
232 // rounding errors could make the argument of asin greater than 1
233 // (This should almost never happen.)
234 if (java.lang.Double.isNaN(d)) {
235 System.err.println("Error: NaN in greatCircleDistance");
236 d = PI * R;
237 }
238 return d;
239 }
240
241 /**
242 * Returns the heading, in radians, that you have to use to get from
243 * this lat/lon to another.
244 *
245 * (I don't know the original source of this formula, but see
246 * http://math.stackexchange.com/questions/720/how-to-calculate-a-heading-on-the-earths-surface
247 * for some hints how it is derived.)
248 *
249 * @param other the "destination" position
250 * @return heading in the range 0 <= hd < 2*PI
251 */
252 public double heading(LatLon other) {
253 double hd = atan2(sin(toRadians(this.lon() - other.lon())) * cos(toRadians(other.lat())),
254 cos(toRadians(this.lat())) * sin(toRadians(other.lat())) -
255 sin(toRadians(this.lat())) * cos(toRadians(other.lat())) * cos(toRadians(this.lon() - other.lon())));
256 hd %= 2 * PI;
257 if (hd < 0) {
258 hd += 2 * PI;
259 }
260 return hd;
261 }
262
263 /**
264 * Returns this lat/lon pair in human-readable format.
265 *
266 * @return String in the format "lat=1.23456 deg, lon=2.34567 deg"
267 */
268 public String toDisplayString() {
269 NumberFormat nf = NumberFormat.getInstance();
270 nf.setMaximumFractionDigits(5);
271 return "lat=" + nf.format(lat()) + "\u00B0, lon=" + nf.format(lon()) + "\u00B0";
272 }
273
274 public LatLon interpolate(LatLon ll2, double proportion) {
275 return new LatLon(this.lat() + proportion * (ll2.lat() - this.lat()),
276 this.lon() + proportion * (ll2.lon() - this.lon()));
277 }
278
279 public LatLon getCenter(LatLon ll2) {
280 return new LatLon((this.lat() + ll2.lat())/2.0, (this.lon() + ll2.lon())/2.0);
281 }
282
283 @Override public String toString() {
284 return "LatLon[lat="+lat()+",lon="+lon()+"]";
285 }
286
287 /**
288 * Returns the value rounded to OSM precisions, i.e. to
289 * LatLon.MAX_SERVER_PRECISION
290 *
291 * @return rounded value
292 */
293 public static double roundToOsmPrecision(double value) {
294 return Math.round(value * MAX_SERVER_INV_PRECISION) / MAX_SERVER_INV_PRECISION;
295 }
296
297 /**
298 * Returns the value rounded to OSM precision. This function is now the same as
299 * {@link #roundToOsmPrecision(double)}, since the rounding error has been fixed.
300 *
301 * @return rounded value
302 */
303 public static double roundToOsmPrecisionStrict(double value) {
304 return roundToOsmPrecision(value);
305 }
306
307 /**
308 * Replies a clone of this lat LatLon, rounded to OSM precisions, i.e. to
309 * MAX_SERVER_PRECISION
310 *
311 * @return a clone of this lat LatLon
312 */
313 public LatLon getRoundedToOsmPrecision() {
314 return new LatLon(
315 roundToOsmPrecision(lat()),
316 roundToOsmPrecision(lon())
317 );
318 }
319
320 /**
321 * Replies a clone of this lat LatLon, rounded to OSM precisions, i.e. to
322 * MAX_SERVER_PRECISION
323 *
324 * @return a clone of this lat LatLon
325 */
326 public LatLon getRoundedToOsmPrecisionStrict() {
327 return new LatLon(
328 roundToOsmPrecisionStrict(lat()),
329 roundToOsmPrecisionStrict(lon())
330 );
331 }
332
333 @Override
334 public int hashCode() {
335 final int prime = 31;
336 int result = super.hashCode();
337 long temp;
338 temp = java.lang.Double.doubleToLongBits(x);
339 result = prime * result + (int) (temp ^ (temp >>> 32));
340 temp = java.lang.Double.doubleToLongBits(y);
341 result = prime * result + (int) (temp ^ (temp >>> 32));
342 return result;
343 }
344
345 @Override
346 public boolean equals(Object obj) {
347 if (this == obj)
348 return true;
349 if (!super.equals(obj))
350 return false;
351 if (getClass() != obj.getClass())
352 return false;
353 Coordinate other = (Coordinate) obj;
354 if (java.lang.Double.doubleToLongBits(x) != java.lang.Double.doubleToLongBits(other.x))
355 return false;
356 if (java.lang.Double.doubleToLongBits(y) != java.lang.Double.doubleToLongBits(other.y))
357 return false;
358 return true;
359 }
360}
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