topic Re: Using GeometryEngine. Intersection computes cannot get the Intersection of two lines in .NET Maps SDK Questions

Using GeometryEngine. Intersection computes cannot get the Intersection of two lines

xipeng — Tue, 14 Mar 2017 01:21:54 GMT

Using two lines intersect in the MapView, get the line, is not the point, why? And this line is not shown on the map

My code is as follows：

Esri.ArcGISRuntime.Geometry.Geometry interGeometry = GeometryEngine.Intersection(roadPolyline1, roadPolyline2);

Re: Using GeometryEngine. Intersection computes cannot get the Intersection of two lines

GregDeStigter — Tue, 14 Mar 2017 15:46:05 GMT

The `GeometryEngine.Intersection` method only returns geometries of the same dimension as the input geometries. So for two polylines it will only return a polyline not a point. In the case here where the lines intersect at a single point it will return an empty polyline.

This isn't helpful for finding the intersection point of two crossing lines. The next update of the Runtime API will have another `GeometryEngine` method that returns multiple geometries including geometries of lesser dimensions. You'll be able to use this to get the intersection point of two polylines.

In the meantime, you may be able to use another `GeometryEngine` method to help find the intersection points. For instance, `GeometryEngine.Cut` with the same input polylines will return separate lines and you can match up the start and end points to infer the intersection point. Not ideal, but would work for the simple case.

Re: Using GeometryEngine. Intersection computes cannot get the Intersection of two lines

xipeng — Wed, 15 Mar 2017 01:07:54 GMT

Thank you for your answer