如何使用NetTopologySuite获取两点几何的距离，单位为米？

Question

如何使用NetTopologySuite获取以米为单位的两点几何图形的距离。

我使用了Distance()函数，但是我得到了一些值，并且我不能识别这些值的单位。c#应用程序忽略要忽略的20米的公差值。

using NetTopologySuite.Geometries;
using GeoAPI.Geometries;

private static double findistance()
{
   var geomFactory = new GeometryFactory(new PrecisionModel(), 4326);
   IGeometry geometry1 = geomFactory.CreatePoint(new Coordinate(12.977299, 77.571075));
   IGeometry geometry2 = geomFactory.CreatePoint(new Coordinate(12.977277, 77.571258));
   var distance = geometry1.Distance(geometry2);
   return distance;
}

我需要以米为单位计算距离。

Answer 1

你可以使用毕达哥拉斯定理来计算距离。

以下是步骤：

1. Get Deltas
   • double int deltaX = Math.Abs(point1.X -point1.Y= Math.Abs(point1.Y -point1.y

1. 毕达哥拉斯公式
   • 双倍距离= Math.Sqrt((deltaX * deltaX) + (deltaY *

如果要计算3D点，除了计算DeltaZ和公式= X^2 + Y^2 + Z^2之外，步骤相同

Answer 2

根据docs，SRID4326代表下面的定义

GEOGCS["WGS 84",
  DATUM["WGS_1984",
    SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],
    AUTHORITY["EPSG","6326"]],
  PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],
  UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],
  AUTHORITY["EPSG","4326"]]

UNIT["degree"...告诉我们，您得到的结果具有度量值。如果我们将这些点转换成投影坐标系，我们就可以计算出以米为单位的距离。ProjNET4GeoAPI包可以为我们做到这一点。

private static double findDistance()
{
    CoordinateTransformationFactory ctfac = new CoordinateTransformationFactory();

    var from = GeographicCoordinateSystem.WGS84;
    var to = ProjectedCoordinateSystem.WebMercator;

    var trans = ctfac.CreateFromCoordinateSystems(from, to);
    var mathTransform = trans.MathTransform;

    var p1Coordinate = new GeoAPI.Geometries.Coordinate(12.977299, 77.571075);
    var p2Coordinate = new GeoAPI.Geometries.Coordinate(12.977277, 77.571258);

    p1Coordinate = mathTransform.Transform(p1Coordinate);
    p2Coordinate = mathTransform.Transform(p2Coordinate);

    return p1Coordinate.Distance(p2Coordinate);
}