By Daniel Du
Q:
I'd like to know how to compute the distance of two points using map 3D .net API
A:
Here is the sample code to do the same:
[CommandMethod("ComputeDistance")]
public void ComputeDistance()
{
//I am using LL84 coordinate system for this sample
//As an example, this is longtitue/Latitue of two points
double x1 = -87.7104750022991;
double y1 = 43.7017449116101;
double x2 = -87.703061972587;
double y2 = 43.7016702994388;
Editor ed = Application.DocumentManager.MdiActiveDocument.Editor;
//Get coordinate system of current map
AcMapMap currentMap = AcMapMap.GetCurrentMap();
string srsWkt = currentMap.GetMapSRS();
//ed.WriteMessage("srs = " + srsWkt + "\n");
MgCoordinateSystemFactory coordSysFactory = new MgCoordinateSystemFactory();
MgCoordinateSystem coordSys = coordSysFactory.Create(srsWkt);
//compute gread circle distance
double distance = coordSys.MeasureGreatCircleDistance(x1, y1, x2, y2);
distance = coordSys.ConvertCoordinateSystemUnitsToMeters(distance);
ed.WriteMessage("gread circle dist = " + distance.ToString() + "\n");
//compute Euclidean distance
distance = coordSys.MeasureEuclideanDistance(x1, y1, x2, y2);
distance = coordSys.ConvertCoordinateSystemUnitsToMeters(distance);
ed.WriteMessage("Euclidean distance = " + distance.ToString() + "\n");
//Another method, compute the distance from Newyork to Boston
MgCoordinateSystemMeasure coordSysMeasure = coordSys.GetMeasure();
double dist = coordSysMeasure.GetDistance(-74.806394, 40.714169, -71.061342, 42.355892);
dist = coordSys.ConvertCoordinateSystemUnitsToMeters(dist);
ed.WriteMessage("distance from Newyork to Boston is " + dist.ToString() + " meters\n");
}
Hope this helps.
