mirror of
https://github.com/meshtastic/firmware.git
synced 2025-02-10 06:31:25 +00:00
486 lines
18 KiB
C++
486 lines
18 KiB
C++
#include "GeoCoord.h"
|
|
|
|
GeoCoord::GeoCoord()
|
|
{
|
|
_dirty = true;
|
|
}
|
|
|
|
GeoCoord::GeoCoord(int32_t lat, int32_t lon, int32_t alt) : _latitude(lat), _longitude(lon), _altitude(alt)
|
|
{
|
|
GeoCoord::setCoords();
|
|
}
|
|
|
|
GeoCoord::GeoCoord(float lat, float lon, int32_t alt) : _altitude(alt)
|
|
{
|
|
// Change decimial reprsentation to int32_t. I.e., 12.345 becomes 123450000
|
|
_latitude = int32_t(lat * 1e+7);
|
|
_longitude = int32_t(lon * 1e+7);
|
|
GeoCoord::setCoords();
|
|
}
|
|
|
|
GeoCoord::GeoCoord(double lat, double lon, int32_t alt) : _altitude(alt)
|
|
{
|
|
// Change decimial reprsentation to int32_t. I.e., 12.345 becomes 123450000
|
|
_latitude = int32_t(lat * 1e+7);
|
|
_longitude = int32_t(lon * 1e+7);
|
|
GeoCoord::setCoords();
|
|
}
|
|
|
|
// Initialize all the coordinate systems
|
|
void GeoCoord::setCoords()
|
|
{
|
|
double lat = _latitude * 1e-7;
|
|
double lon = _longitude * 1e-7;
|
|
GeoCoord::latLongToDMS(lat, lon, _dms);
|
|
GeoCoord::latLongToUTM(lat, lon, _utm);
|
|
GeoCoord::latLongToMGRS(lat, lon, _mgrs);
|
|
GeoCoord::latLongToOSGR(lat, lon, _osgr);
|
|
GeoCoord::latLongToOLC(lat, lon, _olc);
|
|
_dirty = false;
|
|
}
|
|
|
|
void GeoCoord::updateCoords(int32_t lat, int32_t lon, int32_t alt)
|
|
{
|
|
// If marked dirty or new coordiantes
|
|
if (_dirty || _latitude != lat || _longitude != lon || _altitude != alt) {
|
|
_dirty = true;
|
|
_latitude = lat;
|
|
_longitude = lon;
|
|
_altitude = alt;
|
|
setCoords();
|
|
}
|
|
}
|
|
|
|
void GeoCoord::updateCoords(const double lat, const double lon, const int32_t alt)
|
|
{
|
|
int32_t iLat = lat * 1e+7;
|
|
int32_t iLon = lon * 1e+7;
|
|
// If marked dirty or new coordiantes
|
|
if (_dirty || _latitude != iLat || _longitude != iLon || _altitude != alt) {
|
|
_dirty = true;
|
|
_latitude = iLat;
|
|
_longitude = iLon;
|
|
_altitude = alt;
|
|
setCoords();
|
|
}
|
|
}
|
|
|
|
void GeoCoord::updateCoords(const float lat, const float lon, const int32_t alt)
|
|
{
|
|
int32_t iLat = lat * 1e+7;
|
|
int32_t iLon = lon * 1e+7;
|
|
// If marked dirty or new coordiantes
|
|
if (_dirty || _latitude != iLat || _longitude != iLon || _altitude != alt) {
|
|
_dirty = true;
|
|
_latitude = iLat;
|
|
_longitude = iLon;
|
|
_altitude = alt;
|
|
setCoords();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Converts lat long coordinates from decimal degrees to degrees minutes seconds format.
|
|
* DD°MM'SS"C DDD°MM'SS"C
|
|
*/
|
|
void GeoCoord::latLongToDMS(const double lat, const double lon, DMS &dms)
|
|
{
|
|
if (lat < 0)
|
|
dms.latCP = 'S';
|
|
else
|
|
dms.latCP = 'N';
|
|
|
|
double latDeg = lat;
|
|
|
|
if (lat < 0)
|
|
latDeg = latDeg * -1;
|
|
|
|
dms.latDeg = floor(latDeg);
|
|
double latMin = (latDeg - dms.latDeg) * 60;
|
|
dms.latMin = floor(latMin);
|
|
dms.latSec = (latMin - dms.latMin) * 60;
|
|
|
|
if (lon < 0)
|
|
dms.lonCP = 'W';
|
|
else
|
|
dms.lonCP = 'E';
|
|
|
|
double lonDeg = lon;
|
|
|
|
if (lon < 0)
|
|
lonDeg = lonDeg * -1;
|
|
|
|
dms.lonDeg = floor(lonDeg);
|
|
double lonMin = (lonDeg - dms.lonDeg) * 60;
|
|
dms.lonMin = floor(lonMin);
|
|
dms.lonSec = (lonMin - dms.lonMin) * 60;
|
|
}
|
|
|
|
/**
|
|
* Converts lat long coordinates to UTM.
|
|
* based on this: https://github.com/walvok/LatLonToUTM/blob/master/latlon_utm.ino
|
|
*/
|
|
void GeoCoord::latLongToUTM(const double lat, const double lon, UTM &utm)
|
|
{
|
|
|
|
const std::string latBands = "CDEFGHJKLMNPQRSTUVWXX";
|
|
utm.zone = int((lon + 180) / 6 + 1);
|
|
utm.band = latBands[int(lat / 8 + 10)];
|
|
double a = 6378137; // WGS84 - equatorial radius
|
|
double k0 = 0.9996; // UTM point scale on the central meridian
|
|
double eccSquared = 0.00669438; // eccentricity squared
|
|
double lonTemp = (lon + 180) - int((lon + 180) / 360) * 360 - 180; // Make sure the longitude is between -180.00 .. 179.9
|
|
double latRad = toRadians(lat);
|
|
double lonRad = toRadians(lonTemp);
|
|
|
|
// Special Zones for Norway and Svalbard
|
|
if (lat >= 56.0 && lat < 64.0 && lonTemp >= 3.0 && lonTemp < 12.0) // Norway
|
|
utm.zone = 32;
|
|
if (lat >= 72.0 && lat < 84.0) { // Svalbard
|
|
if (lonTemp >= 0.0 && lonTemp < 9.0)
|
|
utm.zone = 31;
|
|
else if (lonTemp >= 9.0 && lonTemp < 21.0)
|
|
utm.zone = 33;
|
|
else if (lonTemp >= 21.0 && lonTemp < 33.0)
|
|
utm.zone = 35;
|
|
else if (lonTemp >= 33.0 && lonTemp < 42.0)
|
|
utm.zone = 37;
|
|
}
|
|
|
|
double lonOrigin = (utm.zone - 1) * 6 - 180 + 3; // puts origin in middle of zone
|
|
double lonOriginRad = toRadians(lonOrigin);
|
|
double eccPrimeSquared = (eccSquared) / (1 - eccSquared);
|
|
double N = a / sqrt(1 - eccSquared * sin(latRad) * sin(latRad));
|
|
double T = tan(latRad) * tan(latRad);
|
|
double C = eccPrimeSquared * cos(latRad) * cos(latRad);
|
|
double A = cos(latRad) * (lonRad - lonOriginRad);
|
|
double M =
|
|
a * ((1 - eccSquared / 4 - 3 * eccSquared * eccSquared / 64 - 5 * eccSquared * eccSquared * eccSquared / 256) * latRad -
|
|
(3 * eccSquared / 8 + 3 * eccSquared * eccSquared / 32 + 45 * eccSquared * eccSquared * eccSquared / 1024) *
|
|
sin(2 * latRad) +
|
|
(15 * eccSquared * eccSquared / 256 + 45 * eccSquared * eccSquared * eccSquared / 1024) * sin(4 * latRad) -
|
|
(35 * eccSquared * eccSquared * eccSquared / 3072) * sin(6 * latRad));
|
|
utm.easting = (double)(k0 * N *
|
|
(A + (1 - T + C) * pow(A, 3) / 6 +
|
|
(5 - 18 * T + T * T + 72 * C - 58 * eccPrimeSquared) * A * A * A * A * A / 120) +
|
|
500000.0);
|
|
utm.northing =
|
|
(double)(k0 * (M + N * tan(latRad) *
|
|
(A * A / 2 + (5 - T + 9 * C + 4 * C * C) * A * A * A * A / 24 +
|
|
(61 - 58 * T + T * T + 600 * C - 330 * eccPrimeSquared) * A * A * A * A * A * A / 720)));
|
|
|
|
if (lat < 0)
|
|
utm.northing += 10000000.0; // 10000000 meter offset for southern hemisphere
|
|
}
|
|
|
|
// Converts lat long coordinates to an MGRS.
|
|
void GeoCoord::latLongToMGRS(const double lat, const double lon, MGRS &mgrs)
|
|
{
|
|
const std::string e100kLetters[3] = {"ABCDEFGH", "JKLMNPQR", "STUVWXYZ"};
|
|
const std::string n100kLetters[2] = {"ABCDEFGHJKLMNPQRSTUV", "FGHJKLMNPQRSTUVABCDE"};
|
|
UTM utm;
|
|
latLongToUTM(lat, lon, utm);
|
|
mgrs.zone = utm.zone;
|
|
mgrs.band = utm.band;
|
|
double col = floor(utm.easting / 100000);
|
|
mgrs.east100k = e100kLetters[(mgrs.zone - 1) % 3][col - 1];
|
|
double row = (int32_t)floor(utm.northing / 100000.0) % 20;
|
|
mgrs.north100k = n100kLetters[(mgrs.zone - 1) % 2][row];
|
|
mgrs.easting = (int32_t)utm.easting % 100000;
|
|
mgrs.northing = (int32_t)utm.northing % 100000;
|
|
}
|
|
|
|
/**
|
|
* Converts lat long coordinates to Ordnance Survey Grid Reference (UK National Grid Ref).
|
|
* Based on: https://www.movable-type.co.uk/scripts/latlong-os-gridref.html
|
|
*/
|
|
void GeoCoord::latLongToOSGR(const double lat, const double lon, OSGR &osgr)
|
|
{
|
|
const char letter[] = "ABCDEFGHJKLMNOPQRSTUVWXYZ"; // No 'I' in OSGR
|
|
double a = 6377563.396; // Airy 1830 semi-major axis
|
|
double b = 6356256.909; // Airy 1830 semi-minor axis
|
|
double f0 = 0.9996012717; // National Grid point scale factor on the central meridian
|
|
double phi0 = toRadians(49);
|
|
double lambda0 = toRadians(-2);
|
|
double n0 = -100000;
|
|
double e0 = 400000;
|
|
double e2 = 1 - (b * b) / (a * a); // eccentricity squared
|
|
double n = (a - b) / (a + b);
|
|
|
|
double osgb_Latitude;
|
|
double osgb_Longitude;
|
|
convertWGS84ToOSGB36(lat, lon, osgb_Latitude, osgb_Longitude);
|
|
double phi = osgb_Latitude; // already in radians
|
|
double lambda = osgb_Longitude; // already in radians
|
|
double v = a * f0 / sqrt(1 - e2 * sin(phi) * sin(phi));
|
|
double rho = a * f0 * (1 - e2) / pow(1 - e2 * sin(phi) * sin(phi), 1.5);
|
|
double eta2 = v / rho - 1;
|
|
double mA = (1 + n + (5 / 4) * n * n + (5 / 4) * n * n * n) * (phi - phi0);
|
|
double mB = (3 * n + 3 * n * n + (21 / 8) * n * n * n) * sin(phi - phi0) * cos(phi + phi0);
|
|
// loss of precision in mC & mD due to floating point rounding can cause innaccuracy of northing by a few meters
|
|
double mC = (15 / 8 * n * n + 15 / 8 * n * n * n) * sin(2 * (phi - phi0)) * cos(2 * (phi + phi0));
|
|
double mD = (35 / 24) * n * n * n * sin(3 * (phi - phi0)) * cos(3 * (phi + phi0));
|
|
double m = b * f0 * (mA - mB + mC - mD);
|
|
|
|
double cos3Phi = cos(phi) * cos(phi) * cos(phi);
|
|
double cos5Phi = cos3Phi * cos(phi) * cos(phi);
|
|
double tan2Phi = tan(phi) * tan(phi);
|
|
double tan4Phi = tan2Phi * tan2Phi;
|
|
double I = m + n0;
|
|
double II = (v / 2) * sin(phi) * cos(phi);
|
|
double III = (v / 24) * sin(phi) * cos3Phi * (5 - tan2Phi + 9 * eta2);
|
|
double IIIA = (v / 720) * sin(phi) * cos5Phi * (61 - 58 * tan2Phi + tan4Phi);
|
|
double IV = v * cos(phi);
|
|
double V = (v / 6) * cos3Phi * (v / rho - tan2Phi);
|
|
double VI = (v / 120) * cos5Phi * (5 - 18 * tan2Phi + tan4Phi + 14 * eta2 - 58 * tan2Phi * eta2);
|
|
|
|
double deltaLambda = lambda - lambda0;
|
|
double deltaLambda2 = deltaLambda * deltaLambda;
|
|
double northing =
|
|
I + II * deltaLambda2 + III * deltaLambda2 * deltaLambda2 + IIIA * deltaLambda2 * deltaLambda2 * deltaLambda2;
|
|
double easting = e0 + IV * deltaLambda + V * deltaLambda2 * deltaLambda + VI * deltaLambda2 * deltaLambda2 * deltaLambda;
|
|
|
|
if (easting < 0 || easting > 700000 || northing < 0 || northing > 1300000) // Check if out of boundaries
|
|
osgr = {'I', 'I', 0, 0};
|
|
else {
|
|
uint32_t e100k = floor(easting / 100000);
|
|
uint32_t n100k = floor(northing / 100000);
|
|
int8_t l1 = (19 - n100k) - (19 - n100k) % 5 + floor((e100k + 10) / 5);
|
|
int8_t l2 = (19 - n100k) * 5 % 25 + e100k % 5;
|
|
osgr.e100k = letter[l1];
|
|
osgr.n100k = letter[l2];
|
|
osgr.easting = floor((int)easting % 100000);
|
|
osgr.northing = floor((int)northing % 100000);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Converts lat long coordinates to Open Location Code.
|
|
* Based on: https://github.com/google/open-location-code/blob/main/c/src/olc.c
|
|
*/
|
|
void GeoCoord::latLongToOLC(double lat, double lon, OLC &olc)
|
|
{
|
|
char tempCode[] = "1234567890abc";
|
|
const char kAlphabet[] = "23456789CFGHJMPQRVWX";
|
|
double latitude;
|
|
double longitude = lon;
|
|
double latitude_degrees = std::min(90.0, std::max(-90.0, lat));
|
|
|
|
if (latitude_degrees < 90) // Check latitude less than lat max
|
|
latitude = latitude_degrees;
|
|
else {
|
|
double precision;
|
|
if (OLC_CODE_LEN <= 10)
|
|
precision = pow_neg(20, floor((OLC_CODE_LEN / -2) + 2));
|
|
else
|
|
precision = pow_neg(20, -3) / pow(5, OLC_CODE_LEN - 10);
|
|
latitude = latitude_degrees - precision / 2;
|
|
}
|
|
while (longitude < -180) // Normalize longitude
|
|
longitude += 360;
|
|
while (longitude >= 180)
|
|
longitude -= 360;
|
|
int64_t lat_val = 90 * 2.5e7;
|
|
int64_t lng_val = 180 * 8.192e6;
|
|
lat_val += latitude * 2.5e7;
|
|
lng_val += longitude * 8.192e6;
|
|
size_t pos = OLC_CODE_LEN;
|
|
|
|
if (OLC_CODE_LEN > 10) { // Compute grid part of code if needed
|
|
for (size_t i = 0; i < 5; i++) {
|
|
int lat_digit = lat_val % 5;
|
|
int lng_digit = lng_val % 4;
|
|
int ndx = lat_digit * 4 + lng_digit;
|
|
tempCode[pos--] = kAlphabet[ndx];
|
|
lat_val /= 5;
|
|
lng_val /= 4;
|
|
}
|
|
} else {
|
|
lat_val /= pow(5, 5);
|
|
lng_val /= pow(4, 5);
|
|
}
|
|
|
|
pos = 10;
|
|
|
|
for (size_t i = 0; i < 5; i++) { // Compute pair section of code
|
|
int lat_ndx = lat_val % 20;
|
|
int lng_ndx = lng_val % 20;
|
|
tempCode[pos--] = kAlphabet[lng_ndx];
|
|
tempCode[pos--] = kAlphabet[lat_ndx];
|
|
lat_val /= 20;
|
|
lng_val /= 20;
|
|
|
|
if (i == 0)
|
|
tempCode[pos--] = '+';
|
|
}
|
|
|
|
if (OLC_CODE_LEN < 9) { // Add padding if needed
|
|
for (size_t i = OLC_CODE_LEN; i < 9; i++)
|
|
tempCode[i] = '0';
|
|
tempCode[9] = '+';
|
|
}
|
|
|
|
size_t char_count = OLC_CODE_LEN;
|
|
if (10 > char_count) {
|
|
char_count = 10;
|
|
}
|
|
for (size_t i = 0; i < char_count; i++) {
|
|
olc.code[i] = tempCode[i];
|
|
}
|
|
olc.code[char_count] = '\0';
|
|
}
|
|
|
|
// Converts the coordinate in WGS84 datum to the OSGB36 datum.
|
|
void GeoCoord::convertWGS84ToOSGB36(const double lat, const double lon, double &osgb_Latitude, double &osgb_Longitude)
|
|
{
|
|
// Convert lat long to cartesian
|
|
double phi = toRadians(lat);
|
|
double lambda = toRadians(lon);
|
|
double h = 0.0; // No OSTN height data used, some loss of accuracy (up to 5m)
|
|
double wgsA = 6378137; // WGS84 datum semi major axis
|
|
double wgsF = 1 / 298.257223563; // WGS84 datum flattening
|
|
double ecc = 2 * wgsF - wgsF * wgsF;
|
|
double vee = wgsA / sqrt(1 - ecc * pow(sin(phi), 2));
|
|
double wgsX = (vee + h) * cos(phi) * cos(lambda);
|
|
double wgsY = (vee + h) * cos(phi) * sin(lambda);
|
|
double wgsZ = ((1 - ecc) * vee + h) * sin(phi);
|
|
|
|
// 7-parameter Helmert transform
|
|
double tx = -446.448; // x shift in meters
|
|
double ty = 125.157; // y shift in meters
|
|
double tz = -542.060; // z shift in meters
|
|
double s = 20.4894 / 1e6 + 1; // scale normalized parts per million to (s + 1)
|
|
double rx = toRadians(-0.1502 / 3600); // x rotation normalize arcseconds to radians
|
|
double ry = toRadians(-0.2470 / 3600); // y rotation normalize arcseconds to radians
|
|
double rz = toRadians(-0.8421 / 3600); // z rotation normalize arcseconds to radians
|
|
double osgbX = tx + wgsX * s - wgsY * rz + wgsZ * ry;
|
|
double osgbY = ty + wgsX * rz + wgsY * s - wgsZ * rx;
|
|
double osgbZ = tz - wgsX * ry + wgsY * rx + wgsZ * s;
|
|
|
|
// Convert cartesian to lat long
|
|
double airyA = 6377563.396; // Airy1830 datum semi major axis
|
|
double airyB = 6356256.909; // Airy1830 datum semi minor axis
|
|
double airyF = 1 / 299.3249646; // Airy1830 datum flattening
|
|
double airyEcc = 2 * airyF - airyF * airyF;
|
|
double airyEcc2 = airyEcc / (1 - airyEcc);
|
|
double p = sqrt(osgbX * osgbX + osgbY * osgbY);
|
|
double R = sqrt(p * p + osgbZ * osgbZ);
|
|
double tanBeta = (airyB * osgbZ) / (airyA * p) * (1 + airyEcc2 * airyB / R);
|
|
double sinBeta = tanBeta / sqrt(1 + tanBeta * tanBeta);
|
|
double cosBeta = sinBeta / tanBeta;
|
|
osgb_Latitude = atan2(osgbZ + airyEcc2 * airyB * sinBeta * sinBeta * sinBeta,
|
|
p - airyEcc * airyA * cosBeta * cosBeta * cosBeta); // leave in radians
|
|
osgb_Longitude = atan2(osgbY, osgbX); // leave in radians
|
|
// osgb height = p*cos(osgb.latitude) + osgbZ*sin(osgb.latitude) -
|
|
//(airyA*airyA/(airyA / sqrt(1 - airyEcc*sin(osgb.latitude)*sin(osgb.latitude)))); // Not used, no OSTN data
|
|
}
|
|
|
|
/// Ported from my old java code, returns distance in meters along the globe
|
|
/// surface (by magic?)
|
|
float GeoCoord::latLongToMeter(double lat_a, double lng_a, double lat_b, double lng_b)
|
|
{
|
|
double pk = (180 / 3.14169);
|
|
double a1 = lat_a / pk;
|
|
double a2 = lng_a / pk;
|
|
double b1 = lat_b / pk;
|
|
double b2 = lng_b / pk;
|
|
double cos_b1 = cos(b1);
|
|
double cos_a1 = cos(a1);
|
|
double t1 = cos_a1 * cos(a2) * cos_b1 * cos(b2);
|
|
double t2 = cos_a1 * sin(a2) * cos_b1 * sin(b2);
|
|
double t3 = sin(a1) * sin(b1);
|
|
double tt = acos(t1 + t2 + t3);
|
|
if (std::isnan(tt))
|
|
tt = 0.0; // Must have been the same point?
|
|
|
|
return (float)(6366000 * tt);
|
|
}
|
|
|
|
/**
|
|
* Computes the bearing in degrees between two points on Earth. Ported from my
|
|
* old Gaggle android app.
|
|
*
|
|
* @param lat1
|
|
* Latitude of the first point
|
|
* @param lon1
|
|
* Longitude of the first point
|
|
* @param lat2
|
|
* Latitude of the second point
|
|
* @param lon2
|
|
* Longitude of the second point
|
|
* @return Bearing from point 1 to point 2 in radians. A value of 0 means due
|
|
* north.
|
|
*/
|
|
float GeoCoord::bearing(double lat1, double lon1, double lat2, double lon2)
|
|
{
|
|
double lat1Rad = toRadians(lat1);
|
|
double lat2Rad = toRadians(lat2);
|
|
double deltaLonRad = toRadians(lon2 - lon1);
|
|
double y = sin(deltaLonRad) * cos(lat2Rad);
|
|
double x = cos(lat1Rad) * sin(lat2Rad) - (sin(lat1Rad) * cos(lat2Rad) * cos(deltaLonRad));
|
|
return atan2(y, x);
|
|
}
|
|
|
|
/**
|
|
* Ported from http://www.edwilliams.org/avform147.htm#Intro
|
|
* @brief Convert from meters to range in radians on a great circle
|
|
* @param range_meters
|
|
* The range in meters
|
|
* @return range in radians on a great circle
|
|
*/
|
|
float GeoCoord::rangeMetersToRadians(double range_meters)
|
|
{
|
|
// 1 nm is 1852 meters
|
|
double distance_nm = range_meters * 1852;
|
|
return (PI / (180 * 60)) * distance_nm;
|
|
}
|
|
|
|
/**
|
|
* Ported from http://www.edwilliams.org/avform147.htm#Intro
|
|
* @brief Convert from radians to range in meters on a great circle
|
|
* @param range_radians
|
|
* The range in radians
|
|
* @return Range in meters on a great circle
|
|
*/
|
|
float GeoCoord::rangeRadiansToMeters(double range_radians)
|
|
{
|
|
double distance_nm = ((180 * 60) / PI) * range_radians;
|
|
// 1 meter is 0.000539957 nm
|
|
return distance_nm * 0.000539957;
|
|
}
|
|
|
|
// Find distance from point to passed in point
|
|
int32_t GeoCoord::distanceTo(const GeoCoord &pointB)
|
|
{
|
|
return latLongToMeter(this->getLatitude() * 1e-7, this->getLongitude() * 1e-7, pointB.getLatitude() * 1e-7,
|
|
pointB.getLongitude() * 1e-7);
|
|
}
|
|
|
|
// Find bearing from point to passed in point
|
|
int32_t GeoCoord::bearingTo(const GeoCoord &pointB)
|
|
{
|
|
return bearing(this->getLatitude() * 1e-7, this->getLongitude() * 1e-7, pointB.getLatitude() * 1e-7,
|
|
pointB.getLongitude() * 1e-7);
|
|
}
|
|
|
|
/**
|
|
* Create a new point bassed on the passed in poin
|
|
* Ported from http://www.edwilliams.org/avform147.htm#LL
|
|
* @param bearing
|
|
* The bearing in raidans
|
|
* @param range_meters
|
|
* range in meters
|
|
* @return GeoCoord object of point at bearing and range from initial point
|
|
*/
|
|
std::shared_ptr<GeoCoord> GeoCoord::pointAtDistance(double bearing, double range_meters)
|
|
{
|
|
double range_radians = rangeMetersToRadians(range_meters);
|
|
double lat1 = this->getLatitude() * 1e-7;
|
|
double lon1 = this->getLongitude() * 1e-7;
|
|
double lat = asin(sin(lat1) * cos(range_radians) + cos(lat1) * sin(range_radians) * cos(bearing));
|
|
double dlon = atan2(sin(bearing) * sin(range_radians) * cos(lat1), cos(range_radians) - sin(lat1) * sin(lat));
|
|
double lon = fmod(lon1 - dlon + PI, 2 * PI) - PI;
|
|
|
|
return std::make_shared<GeoCoord>(double(lat), double(lon), this->getAltitude());
|
|
}
|