/** * This utility class includes : * 1. distance algorithms * 2. finding center for array of nodes * 3. tile evaluation algorithms * * */ public class MapUtils_1 { private static final String BASE_SHORT_OSM_URL = "http://osm.org/go/"; /** * This array is a lookup table that translates 6-bit positive integger * index values into their "Base64 Alphabet" equivalents as specified * in Table 1 of RFC 2045. */ private static final char intToBase64[] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '_', '@' }; /** * Gets distance in meters */ public static double getDistance(double lat1, double lon1, double lat2, double lon2){ double R = 6371; // km double dLat = Math.toRadians(lat2-lat1); double dLon = Math.toRadians(lon2-lon1); double a = Math.sin(dLat/2) * Math.sin(dLat/2) + Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2)) * Math.sin(dLon/2) * Math.sin(dLon/2); double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a)); return R * c * 1000; } public static double checkLongitude(double longitude) { while (longitude < -180 || longitude > 180) { if (longitude < 0) { longitude += 360; } else { longitude -= 360; } } return longitude; } public static double checkLatitude(double latitude) { while (latitude < -90 || latitude > 90) { if (latitude < 0) { latitude += 180; } else { latitude -= 180; } } if(latitude < -85.0511) { return -85.0511; } else if(latitude > 85.0511){ return 85.0511; } return latitude; } public static int get31TileNumberX(double longitude){ longitude = checkLongitude(longitude); long l = 1l << 31; return (int)((longitude + 180d)/360d * l); } public static int get31TileNumberY( double latitude){ latitude = checkLatitude(latitude); double eval = Math.log( Math.tan(Math.toRadians(latitude)) + 1/Math.cos(Math.toRadians(latitude)) ); long l = 1l << 31; if(eval > Math.PI){ eval = Math.PI; } return (int) ((1 - eval / Math.PI) / 2 * l); } public static double get31LongitudeX(int tileX){ return getLongitudeFromTile(21, tileX /1024f); } public static double get31LatitudeY(int tileY){ return getLatitudeFromTile(21, tileY /1024f); } /** * * Theses methods operate with degrees (evaluating tiles & vice versa) * degree longitude measurements (-180, 180) [27.56 Minsk] // degree latitude measurements (90, -90) [53.9] */ public static double getTileNumberX(float zoom, double longitude){ if(longitude == 180d) { return getPowZoom(zoom) - 1; } longitude = checkLongitude(longitude); return (longitude + 180d)/360d * getPowZoom(zoom); } public static double getTileNumberY(float zoom, double latitude){ latitude = checkLatitude(latitude); double eval = Math.log( Math.tan(Math.toRadians(latitude)) + 1/Math.cos(Math.toRadians(latitude)) ); if (Double.isInfinite(eval) || Double.isNaN(eval)) { latitude = latitude < 0 ? - 89.9 : 89.9; eval = Math.log( Math.tan(Math.toRadians(latitude)) + 1/Math.cos(Math.toRadians(latitude)) ); } double result = (1 - eval / Math.PI) / 2 * getPowZoom(zoom); return result; } public static double getTileEllipsoidNumberY(float zoom, double latitude){ final double E2 = (double) latitude * Math.PI / 180; final long sradiusa = 6378137; final long sradiusb = 6356752; final double J2 = (double) Math.sqrt(sradiusa * sradiusa - sradiusb * sradiusb) / sradiusa; final double M2 = (double) Math.log((1 + Math.sin(E2)) / (1 - Math.sin(E2)))/ 2- J2 * Math.log((1 + J2 * Math.sin(E2))/ (1 - J2 * Math.sin(E2))) / 2; final double B2 = getPowZoom(zoom); return B2 / 2 - M2 * B2 / 2 / Math.PI; } public static double getLatitudeFromEllipsoidTileY(float zoom, float tileNumberY){ final double MerkElipsK = 0.0000001; final long sradiusa = 6378137; final long sradiusb = 6356752; final double FExct = (double) Math.sqrt(sradiusa * sradiusa - sradiusb * sradiusb) / sradiusa; final double TilesAtZoom = getPowZoom(zoom); double result = (tileNumberY - TilesAtZoom / 2) / -(TilesAtZoom / (2 * Math.PI)); result = (2 * Math.atan(Math.exp(result)) - Math.PI / 2) * 180 / Math.PI; double Zu = result / (180 / Math.PI); double yy = (tileNumberY - TilesAtZoom / 2); double Zum1 = Zu; Zu = Math.asin(1 - ((1 + Math.sin(Zum1)) * Math.pow(1 - FExct * Math.sin(Zum1), FExct)) / (Math.exp((2 * yy) / -(TilesAtZoom / (2 * Math.PI))) * Math.pow(1 + FExct * Math.sin(Zum1), FExct))); while (Math.abs(Zum1 - Zu) >= MerkElipsK) { Zum1 = Zu; Zu = Math.asin(1 - ((1 + Math.sin(Zum1)) * Math.pow(1 - FExct * Math.sin(Zum1), FExct)) / (Math.exp((2 * yy) / -(TilesAtZoom / (2 * Math.PI))) * Math.pow(1 + FExct * Math.sin(Zum1), FExct))); } return Zu * 180 / Math.PI; } public static double getLongitudeFromTile(float zoom, double x) { return x / getPowZoom(zoom) * 360.0 - 180.0; } public static double getPowZoom(float zoom){ if(zoom >= 0 && zoom - Math.floor(zoom) < 0.05f){ return 1 << ((int)zoom); } else { return Math.pow(2, zoom); } } public static float calcDiffPixelX(float rotateSin, float rotateCos, float dTileX, float dTileY, float tileSize){ return (rotateCos * dTileX - rotateSin * dTileY) * tileSize ; } public static float calcDiffPixelY(float rotateSin, float rotateCos, float dTileX, float dTileY, float tileSize){ return (rotateSin * dTileX + rotateCos * dTileY) * tileSize ; } public static double getLatitudeFromTile(float zoom, double y){ int sign = y < 0 ? -1 : 1; double result = Math.atan(sign*Math.sinh(Math.PI * (1 - 2 * y / getPowZoom(zoom)))) * 180d / Math.PI; return result; } public static int getPixelShiftX(int zoom, double long1, double long2, int tileSize){ return (int) ((getTileNumberX(zoom, long1) - getTileNumberX(zoom, long2)) * tileSize); } public static int getPixelShiftY(int zoom, double lat1, double lat2, int tileSize){ return (int) ((getTileNumberY(zoom, lat1) - getTileNumberY(zoom, lat2)) * tileSize); } // Examples // System.out.println(buildShortOsmUrl(51.51829d, 0.07347d, 16)); // http://osm.org/go/0EEQsyfu // System.out.println(buildShortOsmUrl(52.30103d, 4.862927d, 18)); // http://osm.org/go/0E4_JiVhs // System.out.println(buildShortOsmUrl(40.59d, -115.213d, 9)); // http://osm.org/go/TelHTB-- public static String buildShortOsmUrl(double latitude, double longitude, int zoom){ long lat = (long) (((latitude + 90d)/180d)*(1l << 32)); long lon = (long) (((longitude + 180d)/360d)*(1l << 32)); long code = interleaveBits(lon, lat); StringBuilder str = new StringBuilder(10); str.append(BASE_SHORT_OSM_URL); // add eight to the zoom level, which approximates an accuracy of one pixel in a tile. for(int i=0; i< Math.ceil((zoom+8)/3d); i++){ str.append(intToBase64[(int) ((code >> (58 - 6 * i)) & 0x3f)]); } // append characters onto the end of the string to represent // partial zoom levels (characters themselves have a granularity of 3 zoom levels). for(int j=0; j< (zoom + 8) % 3 ; j++){ str.append('-'); } str.append("?m"); return str.toString(); } /** * interleaves the bits of two 32-bit numbers. the result is known as a Morton code. */ private static long interleaveBits(long x, long y){ long c = 0; for(byte b = 31; b>=0; b--){ c = (c << 1) | ((x >> b) & 1); c = (c << 1) | ((y >> b) & 1); } return c; } /** * Calculate rotation diff D, that R (rotate) + D = T (targetRotate) * D is between -180, 180 * @param rotate * @param targetRotate * @return */ public static float unifyRotationDiff(float rotate, float targetRotate) { float d = targetRotate - rotate; while(d >= 180){ d -= 360; } while(d < -180){ d += 360; } return d; } /** * Calculate rotation diff D, that R (rotate) + D = T (targetRotate) * D is between -180, 180 * @param rotate * @param targetRotate * @return */ public static float unifyRotationTo360(float rotate) { while(rotate < 0){ rotate += 360; } while(rotate > 360){ rotate -= 360; } return rotate; } /** * @param diff align difference between 2 angles ]-PI, PI] * @return */ public static double alignAngleDifference(double diff) { while(diff > Math.PI) { diff -= 2 * Math.PI; } while(diff <=-Math.PI) { diff += 2 * Math.PI; } return diff; } /** * @param diff align difference between 2 angles ]-180, 180] * @return */ public static double degreesDiff(double a1, double a2) { double diff = a1 - a2; while(diff > 180) { diff -= 360; } while(diff <=-180) { diff += 360; } return diff; } }