22 |
|
|
23 |
return 62.8 * Math.sqrt( 3.1 * (pwrLat + pwrLng) ); |
return 62.8 * Math.sqrt( 3.1 * (pwrLat + pwrLng) ); |
24 |
} |
} |
25 |
|
|
26 |
|
public static float beregnAfstand2(GeoPoint p1, GeoPoint p2) { |
27 |
|
float[] result = new float[1]; |
28 |
|
|
29 |
|
|
30 |
|
computeDistanceAndBearing(p1.latitude, p1.longitude, p2.latitude, p2.longitude, result); |
31 |
|
|
32 |
|
return result[0]; |
33 |
|
} |
34 |
|
|
35 |
|
|
36 |
//Latitude (horizonal), longitude(vertical) so |
//Latitude (horizonal), longitude(vertical) so |
46 |
public static double kmToLongitude( double km) {//denne er kun ca |
public static double kmToLongitude( double km) {//denne er kun ca |
47 |
return km / 62.0; |
return km / 62.0; |
48 |
} |
} |
49 |
|
|
50 |
|
|
51 |
|
|
52 |
|
//Kopieret fra android.location.Location |
53 |
|
private static void computeDistanceAndBearing(double lat1, double lon1, |
54 |
|
double lat2, double lon2, float[] results) { |
55 |
|
// Based on http://www.ngs.noaa.gov/PUBS_LIB/inverse.pdf |
56 |
|
// using the "Inverse Formula" (section 4) |
57 |
|
|
58 |
|
int MAXITERS = 20; |
59 |
|
// Convert lat/long to radians |
60 |
|
lat1 *= Math.PI / 180.0; |
61 |
|
lat2 *= Math.PI / 180.0; |
62 |
|
lon1 *= Math.PI / 180.0; |
63 |
|
lon2 *= Math.PI / 180.0; |
64 |
|
|
65 |
|
double a = 6378137.0; // WGS84 major axis |
66 |
|
double b = 6356752.3142; // WGS84 semi-major axis |
67 |
|
double f = (a - b) / a; |
68 |
|
double aSqMinusBSqOverBSq = (a * a - b * b) / (b * b); |
69 |
|
|
70 |
|
double L = lon2 - lon1; |
71 |
|
double A = 0.0; |
72 |
|
double U1 = Math.atan((1.0 - f) * Math.tan(lat1)); |
73 |
|
double U2 = Math.atan((1.0 - f) * Math.tan(lat2)); |
74 |
|
|
75 |
|
double cosU1 = Math.cos(U1); |
76 |
|
double cosU2 = Math.cos(U2); |
77 |
|
double sinU1 = Math.sin(U1); |
78 |
|
double sinU2 = Math.sin(U2); |
79 |
|
double cosU1cosU2 = cosU1 * cosU2; |
80 |
|
double sinU1sinU2 = sinU1 * sinU2; |
81 |
|
|
82 |
|
double sigma = 0.0; |
83 |
|
double deltaSigma = 0.0; |
84 |
|
double cosSqAlpha = 0.0; |
85 |
|
double cos2SM = 0.0; |
86 |
|
double cosSigma = 0.0; |
87 |
|
double sinSigma = 0.0; |
88 |
|
double cosLambda = 0.0; |
89 |
|
double sinLambda = 0.0; |
90 |
|
|
91 |
|
double lambda = L; // initial guess |
92 |
|
for (int iter = 0; iter < MAXITERS; iter++) { |
93 |
|
double lambdaOrig = lambda; |
94 |
|
cosLambda = Math.cos(lambda); |
95 |
|
sinLambda = Math.sin(lambda); |
96 |
|
double t1 = cosU2 * sinLambda; |
97 |
|
double t2 = cosU1 * sinU2 - sinU1 * cosU2 * cosLambda; |
98 |
|
double sinSqSigma = t1 * t1 + t2 * t2; // (14) |
99 |
|
sinSigma = Math.sqrt(sinSqSigma); |
100 |
|
cosSigma = sinU1sinU2 + cosU1cosU2 * cosLambda; // (15) |
101 |
|
sigma = Math.atan2(sinSigma, cosSigma); // (16) |
102 |
|
double sinAlpha = (sinSigma == 0) ? 0.0 : |
103 |
|
cosU1cosU2 * sinLambda / sinSigma; // (17) |
104 |
|
cosSqAlpha = 1.0 - sinAlpha * sinAlpha; |
105 |
|
cos2SM = (cosSqAlpha == 0) ? 0.0 : |
106 |
|
cosSigma - 2.0 * sinU1sinU2 / cosSqAlpha; // (18) |
107 |
|
|
108 |
|
double uSquared = cosSqAlpha * aSqMinusBSqOverBSq; // defn |
109 |
|
A = 1 + (uSquared / 16384.0) * // (3) |
110 |
|
(4096.0 + uSquared * |
111 |
|
(-768 + uSquared * (320.0 - 175.0 * uSquared))); |
112 |
|
double B = (uSquared / 1024.0) * // (4) |
113 |
|
(256.0 + uSquared * |
114 |
|
(-128.0 + uSquared * (74.0 - 47.0 * uSquared))); |
115 |
|
double C = (f / 16.0) * |
116 |
|
cosSqAlpha * |
117 |
|
(4.0 + f * (4.0 - 3.0 * cosSqAlpha)); // (10) |
118 |
|
double cos2SMSq = cos2SM * cos2SM; |
119 |
|
deltaSigma = B * sinSigma * // (6) |
120 |
|
(cos2SM + (B / 4.0) * |
121 |
|
(cosSigma * (-1.0 + 2.0 * cos2SMSq) - |
122 |
|
(B / 6.0) * cos2SM * |
123 |
|
(-3.0 + 4.0 * sinSigma * sinSigma) * |
124 |
|
(-3.0 + 4.0 * cos2SMSq))); |
125 |
|
|
126 |
|
lambda = L + |
127 |
|
(1.0 - C) * f * sinAlpha * |
128 |
|
(sigma + C * sinSigma * |
129 |
|
(cos2SM + C * cosSigma * |
130 |
|
(-1.0 + 2.0 * cos2SM * cos2SM))); // (11) |
131 |
|
|
132 |
|
double delta = (lambda - lambdaOrig) / lambda; |
133 |
|
if (Math.abs(delta) < 1.0e-12) { |
134 |
|
break; |
135 |
|
} |
136 |
|
} |
137 |
|
|
138 |
|
float distance = (float) (b * A * (sigma - deltaSigma)); |
139 |
|
results[0] = distance; |
140 |
|
if (results.length > 1) { |
141 |
|
float initialBearing = (float) Math.atan2(cosU2 * sinLambda, |
142 |
|
cosU1 * sinU2 - sinU1 * cosU2 * cosLambda); |
143 |
|
initialBearing *= 180.0 / Math.PI; |
144 |
|
results[1] = initialBearing; |
145 |
|
if (results.length > 2) { |
146 |
|
float finalBearing = (float) Math.atan2(cosU1 * sinLambda, |
147 |
|
-sinU1 * cosU2 + cosU1 * sinU2 * cosLambda); |
148 |
|
finalBearing *= 180.0 / Math.PI; |
149 |
|
results[2] = finalBearing; |
150 |
|
} |
151 |
|
} |
152 |
|
} |
153 |
|
|
154 |
|
/** |
155 |
|
* Computes the approximate distance in meters between two |
156 |
|
* locations, and optionally the initial and final bearings of the |
157 |
|
* shortest path between them. Distance and bearing are defined using the |
158 |
|
* WGS84 ellipsoid. |
159 |
|
* |
160 |
|
* <p> The computed distance is stored in results[0]. If results has length |
161 |
|
* 2 or greater, the initial bearing is stored in results[1]. If results has |
162 |
|
* length 3 or greater, the final bearing is stored in results[2]. |
163 |
|
* |
164 |
|
* @param startLatitude the starting latitude |
165 |
|
* @param startLongitude the starting longitude |
166 |
|
* @param endLatitude the ending latitude |
167 |
|
* @param endLongitude the ending longitude |
168 |
|
* @param results an array of floats to hold the results |
169 |
|
* |
170 |
|
* @throws IllegalArgumentException if results is null or has length < 1 |
171 |
|
*/ |
172 |
|
public static void distanceBetween(double startLatitude, double startLongitude, |
173 |
|
double endLatitude, double endLongitude, float[] results) { |
174 |
|
if (results == null || results.length < 1) { |
175 |
|
throw new IllegalArgumentException("results is null or has length < 1"); |
176 |
|
} |
177 |
|
computeDistanceAndBearing(startLatitude, startLongitude, |
178 |
|
endLatitude, endLongitude, results); |
179 |
|
} |
180 |
|
|
181 |
} |
} |