source: josm/trunk/src/org/openstreetmap/josm/data/projection/Lambert.java@ 1169

Last change on this file since 1169 was 1169, checked in by stoecker, 15 years ago

removed usage of tab stops
File size: 12.0 KB
Line 
1//License: GPL. For details, see LICENSE file.
2//Thanks to Johan Montagnat and its geoconv java converter application
3//(http://www.i3s.unice.fr/~johan/gps/ , published under GPL license)
4//from which some code and constants have been reused here.
5package org.openstreetmap.josm.data.projection;
6
7import static org.openstreetmap.josm.tools.I18n.tr;
8
9import javax.swing.JOptionPane;
10
11import org.openstreetmap.josm.Main;
12import org.openstreetmap.josm.data.coor.EastNorth;
13import org.openstreetmap.josm.data.coor.LatLon;
14
15public class Lambert implements Projection {
16 /**
17 * Lambert I, II, III, and IV projection exponents
18 */
19 public static final double n[] = { 0.7604059656, 0.7289686274, 0.6959127966, 0.6712679322 };
20
21 /**
22 * Lambert I, II, III, and IV projection constants
23 */
24 public static final double c[] = { 11603796.98, 11745793.39, 11947992.52, 12136281.99 };
25
26 /**
27 * Lambert I, II, III, and IV false east
28 */
29 public static final double Xs[] = { 600000.0, 600000.0, 600000.0, 234.358 };
30
31 /**
32 * Lambert I, II, III, and IV false north
33 */
34 public static final double Ys[] = { 5657616.674, 6199695.768, 6791905.085, 7239161.542 };
35
36 /**
37 * Lambert I, II, III, and IV longitudinal offset to Greenwich meridian
38 */
39 public static final double lg0 = 0.04079234433198; // 2deg20'14.025"
40
41 /**
42 * precision in iterative schema
43 */
44
45 public static final double epsilon = 1e-11;
46
47 /**
48 * France is divided in 4 Lambert projection zones (1,2,3 + 4th for Corsica)
49 */
50 public static final double cMaxLatZone1 = Math.toRadians(57 * 0.9);
51
52 public static final double zoneLimits[] = { Math.toRadians(53.5 * 0.9), // between Zone 1 and Zone 2 (in grad *0.9)
53 Math.toRadians(50.5 * 0.9), // between Zone 2 and Zone 3
54 Math.toRadians(47.51963 * 0.9), // between Zone 3 and Zone 4
55 Math.toRadians(46.17821 * 0.9) };// lowest latitude of Zone 4
56
57 public static final double cMinLonZones = Math.toRadians(-4.9074074074074059 * 0.9);
58
59 public static final double cMaxLonZones = Math.toRadians(10.2 * 0.9);
60
61 /**
62 * Because josm cannot work correctly if two zones are displayed, we allow some overlapping
63 */
64 public static final double cMaxOverlappingZones = Math.toRadians(1.5 * 0.9);
65
66 public static int layoutZone = -1;
67
68 private static int currentZone = 0;
69
70 private static boolean dontDisplayErrors = false;
71
72 /**
73 * @param p WGS84 lat/lon (ellipsoid GRS80) (in degree)
74 * @return eastnorth projection in Lambert Zone (ellipsoid Clark)
75 */
76 public EastNorth latlon2eastNorth(LatLon p) {
77 // translate ellipsoid GRS80 (WGS83) => Clark
78 LatLon geo = GRS802Clark(p);
79 double lt = geo.lat(); // in radian
80 double lg = geo.lon();
81
82 // check if longitude and latitude are inside the french Lambert zones
83 currentZone = 0;
84 boolean outOfLambertZones = false;
85 if (lt >= zoneLimits[3] && lt <= cMaxLatZone1 && lg >= cMinLonZones && lg <= cMaxLonZones) {
86 // zone I
87 if (lt > zoneLimits[0])
88 currentZone = 0;
89 // zone II
90 else if (lt > zoneLimits[1])
91 currentZone = 1;
92 // zone III
93 else if (lt > zoneLimits[2])
94 currentZone = 2;
95 // zone III or IV
96 else if (lt > zoneLimits[3])
97 // Note: zone IV is dedicated to Corsica island and extends from 47.8 to
98 // 45.9 degrees of latitude. There is an overlap with zone III that can be
99 // solved only with longitude (covers Corsica if lon > 7.2 degree)
100 if (lg < Math.toRadians(8 * 0.9))
101 currentZone = 2;
102 else
103 currentZone = 3;
104 } else {
105 outOfLambertZones = true; // possible when MAX_LAT is used
106 if (p.lat() != 0 && Math.abs(p.lat()) != Projection.MAX_LAT
107 && p.lon() != 0 && Math.abs(p.lon()) != Projection.MAX_LON
108 && dontDisplayErrors == false) {
109 JOptionPane.showMessageDialog(Main.parent,
110 tr("The projection \"{0}\" is designed for\n"
111 + "latitudes between 46.1° and 57° only.\n"
112 + "Use another projection system if you are not using\n"
113 + "a french WMS server.\n"
114 + "Do not upload any data after this message.", this.toString()));
115 dontDisplayErrors = true;
116 }
117 }
118 if (!outOfLambertZones) {
119 if (layoutZone == -1) {
120 layoutZone = currentZone;
121 dontDisplayErrors = false;
122 } else if (layoutZone != currentZone) {
123 if ((currentZone < layoutZone && Math.abs(zoneLimits[currentZone] - lt) > cMaxOverlappingZones)
124 || (currentZone > layoutZone && Math.abs(zoneLimits[layoutZone] - lt) > cMaxOverlappingZones)) {
125 JOptionPane.showMessageDialog(Main.parent,
126 tr("IMPORTANT : data positionned far away from\n"
127 + "the current Lambert zone limits.\n"
128 + "Do not upload any data after this message.\n"
129 + "Undo your last action, Save your work \n"
130 + "and Start a new layer on the new zone."));
131 layoutZone = -1;
132 dontDisplayErrors = true;
133 } else {
134 System.out.println("temporarily extend Lambert zone " + layoutZone + " projection at lat,lon:"
135 + lt + "," + lg);
136 }
137 }
138 }
139 if (layoutZone == -1) {
140 return ConicProjection(lt, lg, Xs[currentZone], Ys[currentZone], c[currentZone], n[currentZone]);
141 } // else
142 return ConicProjection(lt, lg, Xs[layoutZone], Ys[layoutZone], c[layoutZone], n[layoutZone]);
143 }
144
145 public LatLon eastNorth2latlon(EastNorth p) {
146 LatLon geo;
147 if (layoutZone == -1)
148 // possible until the Lambert zone is determined by latlon2eastNorth() with a valid LatLon
149 geo = Geographic(p, Xs[currentZone], Ys[currentZone], c[currentZone], n[currentZone]);
150 else
151 geo = Geographic(p, Xs[layoutZone], Ys[layoutZone], c[layoutZone], n[layoutZone]);
152 // translate ellipsoid Clark => GRS80 (WGS83)
153 LatLon wgs = Clark2GRS80(geo);
154 return new LatLon(Math.toDegrees(wgs.lat()), Math.toDegrees(wgs.lon()));
155 }
156
157 @Override public String toString() {
158 return tr("Lambert Zone (France)");
159 }
160
161 public String getCacheDirectoryName() {
162 return "lambert";
163 }
164
165 public double scaleFactor() {
166 return 1.0 / 360;
167 }
168
169 @Override
170 public boolean equals(Object o) {
171 return o instanceof Lambert;
172 }
173
174 @Override
175 public int hashCode() {
176 return Lambert.class.hashCode();
177 }
178
179 /**
180 * Initializes from geographic coordinates. Note that reference ellipsoid
181 * used by Lambert is the Clark ellipsoid.
182 *
183 * @param lat latitude in grad
184 * @param lon longitude in grad
185 * @param Xs false east (coordinate system origin) in meters
186 * @param Ys false north (coordinate system origin) in meters
187 * @param c projection constant
188 * @param n projection exponent
189 * @return EastNorth projected coordinates in meter
190 */
191 private EastNorth ConicProjection(double lat, double lon, double Xs, double Ys, double c, double n) {
192 double eslt = Ellipsoid.clarke.e * Math.sin(lat);
193 double l = Math.log(Math.tan(Math.PI / 4.0 + (lat / 2.0))
194 * Math.pow((1.0 - eslt) / (1.0 + eslt), Ellipsoid.clarke.e / 2.0));
195 double east = Xs + c * Math.exp(-n * l) * Math.sin(n * (lon - lg0));
196 double north = Ys - c * Math.exp(-n * l) * Math.cos(n * (lon - lg0));
197 return new EastNorth(east, north);
198 }
199
200 /**
201 * Initializes from projected coordinates (conic projection). Note that
202 * reference ellipsoid used by Lambert is Clark
203 *
204 * @param coord projected coordinates pair in meters
205 * @param Xs false east (coordinate system origin) in meters
206 * @param Ys false north (coordinate system origin) in meters
207 * @param c projection constant
208 * @param n projection exponent
209 * @return LatLon in radian
210 */
211 private LatLon Geographic(EastNorth eastNorth, double Xs, double Ys, double c, double n) {
212 double dx = eastNorth.east() - Xs;
213 double dy = Ys - eastNorth.north();
214 double R = Math.sqrt(dx * dx + dy * dy);
215 double gamma = Math.atan(dx / dy);
216 double l = -1.0 / n * Math.log(Math.abs(R / c));
217 l = Math.exp(l);
218 double lon = lg0 + gamma / n;
219 double lat = 2.0 * Math.atan(l) - Math.PI / 2.0;
220 double delta = 1.0;
221 while (delta > epsilon) {
222 double eslt = Ellipsoid.clarke.e * Math.sin(lat);
223 double nlt = 2.0 * Math.atan(Math.pow((1.0 + eslt) / (1.0 - eslt), Ellipsoid.clarke.e / 2.0) * l) - Math.PI
224 / 2.0;
225 delta = Math.abs(nlt - lat);
226 lat = nlt;
227 }
228 return new LatLon(lat, lon); // in radian
229 }
230
231 /**
232 * Translate latitude/longitude in WGS84, (ellipsoid GRS80) to Lambert
233 * geographic, (ellipsoid Clark)
234 *
235 * @param wgs
236 * @return
237 */
238 private LatLon GRS802Clark(LatLon wgs) {
239 double lat = Math.toRadians(wgs.lat()); // degree to radian
240 double lon = Math.toRadians(wgs.lon());
241 // WGS84 geographic => WGS84 cartesian
242 double N = Ellipsoid.GRS80.a / (Math.sqrt(1.0 - Ellipsoid.GRS80.e2 * Math.sin(lat) * Math.sin(lat)));
243 double X = (N/* +height */) * Math.cos(lat) * Math.cos(lon);
244 double Y = (N/* +height */) * Math.cos(lat) * Math.sin(lon);
245 double Z = (N * (1.0 - Ellipsoid.GRS80.e2)/* + height */) * Math.sin(lat);
246 // WGS84 => Lambert ellipsoide similarity
247 X += 168.0;
248 Y += 60.0;
249 Z += -320.0;
250 // Lambert cartesian => Lambert geographic
251 return Geographic(X, Y, Z, Ellipsoid.clarke);
252 }
253
254 /**
255 * @param lambert
256 * @return
257 */
258 private LatLon Clark2GRS80(LatLon lambert) {
259 double lat = lambert.lat(); // in radian
260 double lon = lambert.lon();
261 // Lambert geographic => Lambert cartesian
262 double N = Ellipsoid.clarke.a / (Math.sqrt(1.0 - Ellipsoid.clarke.e2 * Math.sin(lat) * Math.sin(lat)));
263 double X = (N/* +height */) * Math.cos(lat) * Math.cos(lon);
264 double Y = (N/* +height */) * Math.cos(lat) * Math.sin(lon);
265 double Z = (N * (1.0 - Ellipsoid.clarke.e2)/* + height */) * Math.sin(lat);
266 // Lambert => WGS84 ellipsoide similarity
267 X += -168.0;
268 Y += -60.0;
269 Z += 320.0;
270 // WGS84 cartesian => WGS84 geographic
271 return Geographic(X, Y, Z, Ellipsoid.GRS80);
272 }
273
274 /**
275 * initializes from cartesian coordinates
276 *
277 * @param X
278 * 1st coordinate in meters
279 * @param Y
280 * 2nd coordinate in meters
281 * @param Z
282 * 3rd coordinate in meters
283 * @param ell
284 * reference ellipsoid
285 */
286 private LatLon Geographic(double X, double Y, double Z, Ellipsoid ell) {
287 double norm = Math.sqrt(X * X + Y * Y);
288 double lg = 2.0 * Math.atan(Y / (X + norm));
289 double lt = Math.atan(Z / (norm * (1.0 - (ell.a * ell.e2 / Math.sqrt(X * X + Y * Y + Z * Z)))));
290 double delta = 1.0;
291 while (delta > epsilon) {
292 double s2 = Math.sin(lt);
293 s2 *= s2;
294 double l = Math.atan((Z / norm)
295 / (1.0 - (ell.a * ell.e2 * Math.cos(lt) / (norm * Math.sqrt(1.0 - ell.e2 * s2)))));
296 delta = Math.abs(l - lt);
297 lt = l;
298 }
299 double s2 = Math.sin(lt);
300 s2 *= s2;
301 // h = norm / Math.cos(lt) - ell.a / Math.sqrt(1.0 - ell.e2 * s2);
302 return new LatLon(lt, lg);
303 }
304
305}
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