Show geodesic sector and ellipse

Create and display geodesic sectors and ellipses.

Use case

Geodesic sectors and ellipses can be used in a wide range of analyses ranging from projectile landing zones to antenna coverage. For example, given the strength and direction of a cellular tower’s signal, you could generate cell coverage geometries to identify areas without sufficient connectivity.

How to use the sample

The geodesic sector and ellipse will display with default parameters at the start. Click anywhere on the map to change the center of the geometries. Adjust any of the controls to see how they affect the sector and ellipse on the fly.

How it works

To create a geodesic sector and ellipse:

1. CreateGeodesicSectorParameters and GeodesicEllipseParameters values.
2. Use center, axisDirection, semiAxis1Length, and semiAxis2Length to set the general ellipse position, shape, and orientation.
3. Use sectorAngle and startDirection to set the sector’s shape and orientation.
4. Use maxPointCount and maxSegmentLength to control the complexity of the geometries and the approximation of the ellipse curve.
5. Use geometryType to change the result geometry type.
6. Pass the parameters to the related static methods: GeometryEngine.geodesicEllipse(parameters:) and GeometryEngine.geodesicSector(parameters:). The returned geometry type is that of the parameters.

Relevant API

GeodesicEllipseParameters GeodesicSectorParameters GeometryEngine

Additional information

To create a circle instead of an ellipse, simply set semiAxis2Length to 0 and semiAxis1Length to the desired radius of the circle. This eliminates the need to update both parameters to the same value.

Tags

ellipse, geodesic, geometry, sector