Cross-platform solution to do geography calculations

Question

I'm working on migrating a .Net framework application to .Net Core and I need to support running on Linux.

The application needs to calculate the intersection of polygons and very long lines on the Earths surface, and so it uses Geography objects as apposed to Geometry to take into account the Earth's elliptical shape.

For this we use Microsoft.SqlServer.Types, which lets us do the following:

    // Line from New York to Paris
    SqlGeography line = SqlGeography.STGeomFromText(new System.Data.SqlTypes.SqlChars("LINESTRING(40.730610 -73.935242, 48.864716 2.349014)"), 4326);
    
    // Polygon in the Atlantic
    SqlGeography polygon = SqlGeography.STGeomFromText(new System.Data.SqlTypes.SqlChars("POLYGON((60 -40, 60 -20, 30 -20, 30 -40, 60 -40))"), 4326);

    // Contains the two locations where the line intersects with the polygon
    SqlGeography intersection = line.STIntersection(polygon);

The problem is that Microsoft.SqlServer.Types only works on Windows. How can I get the same result in a way that will also compile and run on Linux?

I've looked into NetTopologySuite but it seems to only support geometry calculations

Answer 1

Not sure if you are using EFCore or the NetTopology Suite for handling geography data in your project - but all these are already supported in that package.

Microsoft

Nuget

As you are using the WellKnownText format you can use the Docs from here: Github Docs

I can't post the source code of my solution but an example of how to use it would be:

public class GeographyHelper
{
    private static GeometryFactory _geometryFactory
    {
        get
        {
            return NetTopologySuite.NtsGeometryServices.Instance.CreateGeometryFactory(4326);
        }
    }

    public bool TestIntersectsAPolygon(double latitude, double longitude)
    {
        var wellKnownText = "YOUR POLYGON WKT";

        var point = _geometryFactory.CreatePoint(new Coordinate(longitude, latitude));
        var rdr = new NetTopologySuite.IO.WKTReader();
        var geometry = rdr.Read(wellKnownText);

        var polygon =  _geometryFactory.CreatePolygon(geometry.Coordinates);

        var intersects = polygon.Intersects(point);

        return intersects ;
    }
}