co-maps/libs/geometry/distance_on_sphere.cpp

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

39 lines
1.2 KiB
C++
Raw Permalink Normal View History

2025-11-22 13:58:55 +01:00
#include "geometry/distance_on_sphere.hpp"
#include "base/math.hpp"
#include <algorithm>
#include <cmath>
namespace ms
{
double DistanceOnSphere(double lat1Deg, double lon1Deg, double lat2Deg, double lon2Deg)
{
double const lat1 = math::DegToRad(lat1Deg);
double const lat2 = math::DegToRad(lat2Deg);
double const dlat = sin((lat2 - lat1) * 0.5);
double const dlon = sin((math::DegToRad(lon2Deg) - math::DegToRad(lon1Deg)) * 0.5);
double const y = dlat * dlat + dlon * dlon * cos(lat1) * cos(lat2);
return 2.0 * atan2(sqrt(y), sqrt(std::max(0.0, 1.0 - y)));
}
double DistanceOnEarth(double lat1Deg, double lon1Deg, double lat2Deg, double lon2Deg)
{
return kEarthRadiusMeters * DistanceOnSphere(lat1Deg, lon1Deg, lat2Deg, lon2Deg);
}
double DistanceOnEarth(LatLon const & ll1, LatLon const & ll2)
{
return DistanceOnEarth(ll1.m_lat, ll1.m_lon, ll2.m_lat, ll2.m_lon);
}
m3::Point<double> ToVector(LatLon const & ll)
{
double const lat = math::DegToRad(ll.m_lat);
double const lon = math::DegToRad(ll.m_lon);
return {kEarthRadiusMeters * cos(lat) * cos(lon), kEarthRadiusMeters * cos(lat) * sin(lon),
kEarthRadiusMeters * sin(lat)};
}
} // namespace ms