17 lines
573 B
TypeScript
17 lines
573 B
TypeScript
|
export type LatLng = { lat: number; lng: number }
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Storsirkel-avstand mellom to koordinater, i meter. Ren klient-side
|
||
|
|
* beregning -- ingen Mapbox-kall (ADR-048 kostnadskontroll-invariant B).
|
||
|
|
*/
|
||
|
|
export function haversineMeters(a: LatLng, b: LatLng): number {
|
||
|
|
const R = 6371000
|
||
|
|
const toRad = (d: number) => (d * Math.PI) / 180
|
||
|
|
const dLat = toRad(b.lat - a.lat)
|
||
|
|
const dLng = toRad(b.lng - a.lng)
|
||
|
|
const h =
|
||
|
|
Math.sin(dLat / 2) ** 2 +
|
||
|
|
Math.cos(toRad(a.lat)) * Math.cos(toRad(b.lat)) * Math.sin(dLng / 2) ** 2
|
||
|
|
return 2 * R * Math.asin(Math.sqrt(h))
|
||
|
|
}
|