Invalid argument from GeometryEngine when drawing an ellipse

[Tone]

Hi,

I'm fairly new to ArcGIS, I do a bit of testing to see if we could use it for our application. I have a basic application displaying a map, and I want to draw an ellipse on it. I managed to draw circles, but for whatever reason I can't figure out, I have an arcGISRuntimeException : Invalid argument from the GeometryEngine when I run it with my ellipse.

Here is my code  (without my API key):

public class App extends Application {

    private MapView mapView;

    public static void main(String[] args) {

        Application.launch(args);
    }

    @Override
    public void start(Stage stage) {

        stage.setTitle("Carto App");
        stage.setWidth(800);
        stage.setHeight(700);
        stage.show();

        StackPane stackPane = new StackPane();
        Scene scene = new Scene(stackPane);
        stage.setScene(scene);

        String yourApiKey =
                "";
        ArcGISRuntimeEnvironment.setApiKey(yourApiKey);

        mapView = new MapView();
        stackPane.getChildren().add(mapView);

        ArcGISMap map = new ArcGISMap(BasemapStyle.ARCGIS_IMAGERY);

        mapView.setMap(map);

        GraphicsOverlay graphicsOverlay = new GraphicsOverlay();
        mapView.getGraphicsOverlays().add(graphicsOverlay);

        EllipseFigure ellipse = new EllipseFigure(new Point(0, 0), 100, 100, 0, 0xFF00FF00);
        Graphic graphic = new Graphic(ellipse.getGeometry(), ellipse.getSymbol());
        graphicsOverlay.getGraphics().add(graphic);
    }


    /**
     * Stops and releases all resources used in application.
     */
    @Override
    public void stop() {

        if (mapView != null) {
            mapView.dispose();
        }
    }
}

public class EllipseFigure {

    private final double semiMajorAxis;
    private final double semiMinorAxis;
    private Point center;
    private double rotAngle;
    private int color;

    public EllipseFigure(Point center, double semiMajorAxis, double semiMinorAxis, double rotAngle, int color) {
        this.center = center;
        this.semiMajorAxis = semiMajorAxis;
        this.rotAngle = rotAngle;
        this.semiMinorAxis = semiMinorAxis;
        this.color = color;
    }

    public Geometry getGeometry() {
        GeodesicEllipseParameters params =
                new GeodesicEllipseParameters(center, semiMajorAxis, semiMinorAxis);
        params.setAngularUnit(new AngularUnit(AngularUnitId.RADIANS));
        params.setAxisDirection(rotAngle);
        return GeometryEngine.ellipseGeodesic(params);
    }

    public Symbol getSymbol() {
        return new SimpleLineSymbol(SimpleLineSymbol.Style.SOLID, color, 3);
    }
}

I'd really appreciate if someone could help me figure out what's going on here.

[MarkBaird · Accepted solution]

Hi @Tone 

The ellipseGeodesic method is very fussy about its parameters.  You need to make sure you set them all and you also need to pass in a center point which has a known spatial reference.

I've created an example ellipse method which should help you:

  private Polygon makeEllipse() {
    // create parameters and set all the parameters
    GeodesicEllipseParameters parameters = new GeodesicEllipseParameters();

    parameters.setCenter(new Point(3,14, SpatialReferences.getWebMercator())); // Note the spatial reference
    parameters.setGeometryType(GeometryType.POLYGON);
    parameters.setSemiAxis1Length(100);
    parameters.setSemiAxis2Length(200);
    parameters.setAxisDirection(45);
    parameters.setMaxPointCount(100);
    parameters.setAngularUnit(new AngularUnit(AngularUnitId.DEGREES));
    parameters.setLinearUnit(new LinearUnit(LinearUnitId.METERS));
    parameters.setMaxSegmentLength(20);

    Polygon ellipsePoly = (Polygon) GeometryEngine.ellipseGeodesic(parameters);

    return ellipsePoly;
  }

This is how I used the resulting geometry:

      SimpleLineSymbol lineSymbol = new SimpleLineSymbol(SimpleLineSymbol.Style.SOLID, 0xFF0063FF, 1);

      SimpleFillSymbol fillSymbol = new SimpleFillSymbol(SimpleFillSymbol.Style.SOLID, 0xFF00FF00, lineSymbol);

      Graphic graphic = new Graphic(makeEllipse(), fillSymbol);

      graphicsOverlay.getGraphics().add(graphic);

Looks like this:

Let me know if this helps

Mark

[Tone]

Ah, I knew I had a problem with the parameters but couldn't figure out what it was.

Thank you @MarkBaird !