地理坐标操作

Question

正如Esteban A. Maringolo所问：

有没有人实现了基本的方法/类来计算两点之间的距离(lat，long)和类似的操作？

Answer 1

Esteban A. Maringolo找到的解决方案：

distanceFromLat: lat1 long: long1 toLat: lat2 long: long2
"Answer the distance in meters between two coordinates in float number representation."

  | lat1Rad  lon1Rad lat2Rad lon2Rad earthRadius dLat dLon dLatSinSqrd dLonSinSqrd cosLatLat a c distance |
  lat1Rad := lat1 degreesToRadians.
  lon1Rad := long1  degreesToRadians.
  lat2Rad := lat2 degreesToRadians.
  lon2Rad := long2 degreesToRadians.
  earthRadius := 6371.00.
  dLat := lat2Rad - lat1Rad.
  dLon := lon2Rad - lon1Rad.
  dLatSinSqrd := (dLat / 2) sin squared.
  dLonSinSqrd := (dLon / 2) sin squared.
  cosLatLat := lat2Rad cos * lat1Rad cos.
  a := dLatSinSqrd + (cosLatLat * dLonSinSqrd).
  c := 2 * a sqrt arcSin.
  distance := earthRadius * c.
  ^ distance

Answer 2

Sven Van Caekenberghe提出的更简单的解决方案：

这是在Pharo，JavaScript，Common Lisp中使用多年的公式：

distanceBetween: firstPosition and: secondPosition
 "T3GeoTools distanceBetween: 5.33732@50.926 and: 5.49705@50.82733"

 | c |
 c := (firstPosition y degreeSin * secondPosition y degreeSin)
      + (firstPosition y degreeCos * secondPosition y degreeCos
         * (secondPosition x degreesToRadians - firstPosition x degreesToRadians) cos).
 c := c >= 0 ifTrue: [ 1 min: c ] ifFalse: [ -1 max: c ].
 ^ c arcCos * 6371000

这是在WGS84坐标之间。使用此页面作为参考：http://www.movable-type.co.uk/scripts/latlong.html