} // End Function SpatialDistanceBetweenPlaces
// TestTransform.LOLdistance.Test();
public static void Test()
{
var fab = new Wgs84Coordinates(47.552063m, 9.226081m);
var sg = new Wgs84Coordinates(47.374487m, 9.556946m);
double lat1 = (double)fab.Latitude;
double lon1 = (double)fab.Longitude;
double lat2 = (double)sg.Latitude;
double lon2 = (double)sg.Longitude;
double d = LOLdistance.DistanceBetweenPlaces(lat1, lon1, lat2, lon2);
double d3d = LOLdistance.Distance3dBetweenPlaces(lat1, lon1, lat2, lon2);
double fastd = FastDistance.DistanceBetweenPlaces(lat1, lon1, lat2, lon2);
double dp = DistanceAlgorithm.DistanceBetweenPlaces(lat1, lon1, lat2, lon2);
decimal decDistance = DecimalDistanceAlgorithm.DistanceBetweenPlaces(fab.Latitude, fab.Longitude, sg.Latitude, sg.Longitude);
double pd = LOLdistance.ProjectedDistanceBetweenPlaces(fab, sg);
double sd = SpatialDistanceBetweenPlaces(fab, sg);
// DECLARE @fab geography;
// SET @fab = geography::Point(47.552063, 9.226081, 4326)
// DECLARE @sg geography;
// SET @sg = geography::Point(47.374487, 9.556946, 4326)
// SELECT @fab.STDistance(@sg), @sg.STDistance(@fab)-- 31813.1626618977
System.Console.WriteLine("", d, d3d, fastd, dp, decDistance, pd, sd);
}
public static double SpatialDistanceBetweenPlaces(Wgs84Coordinates a, Wgs84Coordinates b)
{
var fablat = new DotSpatial.Positioning.Latitude((double)a.Latitude);
var fablng = new DotSpatial.Positioning.Longitude((double)a.Longitude);
var sglat = new DotSpatial.Positioning.Latitude((double)b.Latitude);
var sglng = new DotSpatial.Positioning.Longitude((double)b.Longitude);
var fab = new DotSpatial.Positioning.Position(fablat, fablng);
var sg = new DotSpatial.Positioning.Position(sglat, sglng);
DotSpatial.Positioning.Distance dist = fab.DistanceTo(sg);
return(dist.ToMeters().Value);
} // End Function SpatialDistanceBetweenPlaces
// https://stackoverflow.com/questions/46159499/calculate-area-of-polygon-having-wgs-coordinates-using-dotspatial
// pfff wrong...
public static void TestComputeArea()
{
// this feature can be see visually here http://www.allhx.ca/on/toronto/westmount-park-road/25/
string feature = "-79.525542519049552,43.691278124243432 -79.525382520578987,43.691281097414787 -79.525228855617627,43.69124858593392 -79.525096151437353,43.691183664769774 -79.52472799258571,43.690927163079735 -79.525379447437814,43.690771996666641 -79.525602330675355,43.691267524226838 -79.525542519049552,43.691278124243432";
feature = "47.3612503,8.5351944 47.3612252,8.5342631 47.3610145,8.5342755 47.3610212,8.5345227 47.3606405,8.5345451 47.3606350,8.5343411 47.3604067,8.5343545 47.3604120,8.5345623 47.3604308,8.5352457 47.3606508,8.5352328 47.3606413,8.5348784 47.3610383,8.5348551 47.3610477,8.5352063 47.3612503,8.5351944";
string[] coordinates = feature.Split(' ');
// System.Array.Reverse(coordinates);
Wgs84Coordinates[] points = new Wgs84Coordinates[coordinates.Length];
for (int i = 0; i < coordinates.Length; i++)
{
double lon = double.Parse(coordinates[i].Split(',')[0]);
double lat = double.Parse(coordinates[i].Split(',')[1]);
points[i] = new Wgs84Coordinates((decimal)lat, (decimal)lon);
} // Next i
double area = CalculateArea(points);
System.Console.WriteLine(area);
} // End Sub TestComputeArea
public static double ProjectedDistanceBetweenPlaces(Wgs84Coordinates a, Wgs84Coordinates b)
{
Wgs84Coordinates[] mycoordinates = new Wgs84Coordinates[] { a, b };
DotSpatial.Projections.ProjectionInfo projFrom = DotSpatial.Projections.KnownCoordinateSystems.Geographic.World.WGS1984;
DotSpatial.Projections.ProjectionInfo projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.World.CylindricalEqualAreaworld;
projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.World.EquidistantConicworld;
// projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.World.EquidistantCylindricalworld;
// projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.World.WebMercator;
projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.WorldSpheroid.Mercatorsphere;
projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.WorldSpheroid.EckertVsphere; // Exception
projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.WorldSpheroid.MillerCylindricalsphere;
projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.WorldSpheroid.EquidistantCylindricalsphere;
// projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.WorldSpheroid.EquidistantConicsphere;
projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.SpheroidBased.Lambert2;
// projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.SpheroidBased.Lambert2Wide;
// projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.WorldSpheroid.EckertIVsphere;
// projTo = DotSpatial.Projections.KnownCoordinateSystems.Projected.Europe.EuropeEquidistantConic;
double[] latLonPoints = new double[mycoordinates.Length * 2];
double[] z = new double[mycoordinates.Length];
// dotspatial takes the x,y in a single array, and z in a separate array. I'm sure there's a
// reason for this, but I don't know what it is.
for (int i = 0; i < mycoordinates.Length; i++)
{
latLonPoints[i * 2] = (double)mycoordinates[i].Longitude;
latLonPoints[i * 2 + 1] = (double)mycoordinates[i].Latitude;
z[i] = 0;
} // Next i
// prepare for ReprojectPoints (it's mutate array)
DotSpatial.Projections.Reproject.ReprojectPoints(
latLonPoints, z, projFrom, projTo
, 0, latLonPoints.Length / 2
);
// assemblying new points array to create polygon
GeoAPI.Geometries.Coordinate[] polyPoints = new GeoAPI.Geometries.Coordinate[latLonPoints.Length / 2];
for (int i = 0; i < latLonPoints.Length / 2; ++i)
{
polyPoints[i] = new GeoAPI.Geometries.Coordinate(latLonPoints[i * 2], latLonPoints[i * 2 + 1]);
} // Next i
// Assembling linear ring to create polygon
// NetTopologySuite.Geometries.LinearRing lr = new NetTopologySuite.Geometries.LinearRing(polyPoints);
var line = new NetTopologySuite.Geometries.LineString(polyPoints);
// var line = new NetTopologySuite.Geometries.LineSegment(polyPoints[0], polyPoints[1]);
line.SRID = 4326;
GeoAPI.Geometries.Coordinate[] unprojPoints = new GeoAPI.Geometries.Coordinate[]
{
new GeoAPI.Geometries.Coordinate((double)a.Latitude, (double)a.Longitude, 0),
new GeoAPI.Geometries.Coordinate((double)b.Latitude, (double)b.Longitude, 0)
};
var unprojline = new NetTopologySuite.Geometries.LineString(unprojPoints);
unprojline.SRID = 4326;
System.Console.WriteLine(unprojline.Length);
double dist = polyPoints[0].Distance(polyPoints[1]);
System.Console.WriteLine(dist);
// SELECT geography::Point(47.552063, 9.226081, 4326).STDistance(geography::Point(47.374487, 9.556946, 4326))
// 31813.1626618977
return(line.Length);
}
