How to calculate using geodesic distance when working with GeometryEngine.CreatePointAlong() ?

KevinCheriyan — Sun, 03 Sep 2023 22:32:43 GMT

I'm using the .NET Maps SDK and GeometryEngine to calculate x distance (in miles) traversed along a polyline and drop a point there. I'm using the CreatePointAlong() method to achieve this. However, when I run this, I get a resulting point that is measured using planar miles. I want this distance to be measured using geodetic miles. How can I achieve this?

My polyline that's being used for the calculation is in Web Mercator (WKID:3857) which is a projected coordinate system with units in meters. Could this be the reason for why the distance measurement is planar?

Here's the WkText for my polyline's SpatialReference:

"PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Mercator_Auxiliary_Sphere"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",0.0],PARAMETER["Standard_Parallel_1",0.0],PARAMETER["Auxiliary_Sphere_Type",0.0],UNIT["Meter",1.0]]"

What else have I tried?

I tried reprojecting the polyline to NAD83 using SpatialReference.Create(4269), but this changed the unit of the polyline to degrees. I need to use miles in my distance measurement, so I believe this is useless.

And finally, I know the resulting point is calculated using planar and not geodetic distance because I compared with ArcGIS Pro's Measure tool which lets me measure using planar and geodetic methods.

Any help would be appreciated! Thanks!

topic How to calculate using geodesic distance when working with GeometryEngine.CreatePointAlong() ? in .NET Maps SDK Questions

How to calculate using geodesic distance when working with GeometryEngine.CreatePointAlong() ?