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| 1 | +package com.javabaas.javasdk; |
| 2 | + |
| 3 | +/** |
| 4 | + * Created by zangyilin on 2018/12/5. |
| 5 | + */ |
| 6 | +public class JBGeoPoint { |
| 7 | + static double EARTH_MEAN_RADIUS_KM = 6378.14D; |
| 8 | + static double ONE_KM_TO_MILES = 1.609344D; |
| 9 | + private double latitude; |
| 10 | + private double longitude; |
| 11 | + /** |
| 12 | + * 维度 |
| 13 | + */ |
| 14 | + static final String LATITUDE_KEY = "latitude"; |
| 15 | + /** |
| 16 | + * 经度 |
| 17 | + */ |
| 18 | + static final String LONGTITUDE_KEY = "longitude"; |
| 19 | + |
| 20 | + public JBGeoPoint() { |
| 21 | + this.latitude = 0.0D; |
| 22 | + this.longitude = 0.0D; |
| 23 | + } |
| 24 | + |
| 25 | + /** |
| 26 | + * 计算本位置到另一位置距离(公里) |
| 27 | + * @param point 位置 |
| 28 | + * @return 距离 |
| 29 | + */ |
| 30 | + public double distanceInKilometersTo(JBGeoPoint point) { |
| 31 | + float[] mResults = new float[2]; |
| 32 | + computeDistanceAndBearing(this.latitude, this.longitude, point.latitude, point.longitude, mResults); |
| 33 | + |
| 34 | + return mResults[0] / 1000.0F; |
| 35 | + } |
| 36 | + |
| 37 | + /** |
| 38 | + * 计算本位置到另一位置距离(英里) |
| 39 | + * @param point 位置 |
| 40 | + * @return 距离 |
| 41 | + */ |
| 42 | + public double distanceInMilesTo(JBGeoPoint point) { |
| 43 | + return distanceInKilometersTo(point) / ONE_KM_TO_MILES; |
| 44 | + } |
| 45 | + |
| 46 | + /** |
| 47 | + * 计算本位置到另一位置弧度 |
| 48 | + * |
| 49 | + * @param point 位置 |
| 50 | + * @return 弧度 |
| 51 | + */ |
| 52 | + public double distanceInRadiansTo(JBGeoPoint point) { |
| 53 | + return distanceInKilometersTo(point) / EARTH_MEAN_RADIUS_KM; |
| 54 | + } |
| 55 | + |
| 56 | + public JBGeoPoint(double latitude, double longitude) { |
| 57 | + this.latitude = latitude; |
| 58 | + this.longitude = longitude; |
| 59 | + } |
| 60 | + |
| 61 | + public double getLatitude() { |
| 62 | + return this.latitude; |
| 63 | + } |
| 64 | + |
| 65 | + public void setLatitude(double l) { |
| 66 | + this.latitude = l; |
| 67 | + } |
| 68 | + |
| 69 | + public double getLongitude() { |
| 70 | + return this.longitude; |
| 71 | + } |
| 72 | + |
| 73 | + public void setLongitude(double l) { |
| 74 | + this.longitude = l; |
| 75 | + } |
| 76 | + |
| 77 | + private static void computeDistanceAndBearing(double lat1, double lon1, double lat2, double lon2, float[] results) { |
| 78 | + int MAXITERS = 20; |
| 79 | + |
| 80 | + lat1 *= 0.017453292519943295D; |
| 81 | + lat2 *= 0.017453292519943295D; |
| 82 | + lon1 *= 0.017453292519943295D; |
| 83 | + lon2 *= 0.017453292519943295D; |
| 84 | + |
| 85 | + double a = 6378137.0D; |
| 86 | + double b = 6356752.3142D; |
| 87 | + double f = (a - b) / a; |
| 88 | + double aSqMinusBSqOverBSq = (a * a - b * b) / (b * b); |
| 89 | + |
| 90 | + double L = lon2 - lon1; |
| 91 | + double A = 0.0D; |
| 92 | + double U1 = Math.atan((1.0D - f) * Math.tan(lat1)); |
| 93 | + double U2 = Math.atan((1.0D - f) * Math.tan(lat2)); |
| 94 | + |
| 95 | + double cosU1 = Math.cos(U1); |
| 96 | + double cosU2 = Math.cos(U2); |
| 97 | + double sinU1 = Math.sin(U1); |
| 98 | + double sinU2 = Math.sin(U2); |
| 99 | + double cosU1cosU2 = cosU1 * cosU2; |
| 100 | + double sinU1sinU2 = sinU1 * sinU2; |
| 101 | + |
| 102 | + double sigma = 0.0D; |
| 103 | + double deltaSigma = 0.0D; |
| 104 | + double cosSqAlpha = 0.0D; |
| 105 | + double cos2SM = 0.0D; |
| 106 | + double cosSigma = 0.0D; |
| 107 | + double sinSigma = 0.0D; |
| 108 | + double cosLambda = 0.0D; |
| 109 | + double sinLambda = 0.0D; |
| 110 | + |
| 111 | + double lambda = L; |
| 112 | + for (int iter = 0; iter < MAXITERS; iter++) { |
| 113 | + double lambdaOrig = lambda; |
| 114 | + cosLambda = Math.cos(lambda); |
| 115 | + sinLambda = Math.sin(lambda); |
| 116 | + double t1 = cosU2 * sinLambda; |
| 117 | + double t2 = cosU1 * sinU2 - sinU1 * cosU2 * cosLambda; |
| 118 | + double sinSqSigma = t1 * t1 + t2 * t2; |
| 119 | + sinSigma = Math.sqrt(sinSqSigma); |
| 120 | + cosSigma = sinU1sinU2 + cosU1cosU2 * cosLambda; |
| 121 | + sigma = Math.atan2(sinSigma, cosSigma); |
| 122 | + double sinAlpha = sinSigma == 0.0D ? 0.0D : cosU1cosU2 * sinLambda / sinSigma; |
| 123 | + cosSqAlpha = 1.0D - sinAlpha * sinAlpha; |
| 124 | + cos2SM = cosSqAlpha == 0.0D ? 0.0D : cosSigma - 2.0D * sinU1sinU2 / cosSqAlpha; |
| 125 | + |
| 126 | + double uSquared = cosSqAlpha * aSqMinusBSqOverBSq; |
| 127 | + A = 1.0D + uSquared / 16384.0D * (4096.0D + uSquared * (-768.0D + uSquared * (320.0D - 175.0D * uSquared))); |
| 128 | + |
| 129 | + double B = uSquared / 1024.0D * (256.0D + uSquared * (-128.0D + uSquared * (74.0D - 47.0D * uSquared))); |
| 130 | + |
| 131 | + double C = f / 16.0D * cosSqAlpha * (4.0D + f * (4.0D - 3.0D * cosSqAlpha)); |
| 132 | + double cos2SMSq = cos2SM * cos2SM; |
| 133 | + deltaSigma = B * sinSigma * (cos2SM + B / 4.0D * (cosSigma * (-1.0D + 2.0D * cos2SMSq) - B / 6.0D * cos2SM * (-3.0D + 4.0D * sinSigma * sinSigma) * (-3.0D + 4.0D * cos2SMSq))); |
| 134 | + |
| 135 | + lambda = L + (1.0D - C) * f * sinAlpha * (sigma + C * sinSigma * (cos2SM + C * cosSigma * (-1.0D + 2.0D * cos2SM * cos2SM))); |
| 136 | + |
| 137 | + double delta = (lambda - lambdaOrig) / lambda; |
| 138 | + if (Math.abs(delta) < 1.0E-12D) { |
| 139 | + break; |
| 140 | + } |
| 141 | + } |
| 142 | + float distance = (float)(b * A * (sigma - deltaSigma)); |
| 143 | + results[0] = distance; |
| 144 | + if (results.length > 1) { |
| 145 | + float initialBearing = (float)Math.atan2(cosU2 * sinLambda, cosU1 * sinU2 - sinU1 * cosU2 * cosLambda); |
| 146 | + initialBearing = (float)(initialBearing * 57.29577951308232D); |
| 147 | + results[1] = initialBearing; |
| 148 | + if (results.length > 2) { |
| 149 | + float finalBearing = (float)Math.atan2(cosU1 * sinLambda, -sinU1 * cosU2 + cosU1 * sinU2 * cosLambda); |
| 150 | + finalBearing = (float)(finalBearing * 57.29577951308232D); |
| 151 | + results[2] = finalBearing; |
| 152 | + } |
| 153 | + } |
| 154 | + } |
| 155 | +} |
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