distanceBetween function
return result in meter
Implementation
double distanceBetween(
double startLatitude,
double startLongitude,
double endLatitude,
double endLongitude,
) {
const earthRadius = 6378137.0;
final dLat = _toRadians(endLatitude - startLatitude);
final dLon = _toRadians(endLongitude - startLongitude);
final a = pow(sin(dLat / 2), 2) +
pow(sin(dLon / 2), 2) *
cos(_toRadians(startLatitude)) *
cos(_toRadians(endLatitude));
final c = 2 * asin(sqrt(a));
return earthRadius * c;
}