Entity on wrong position after downscaling globe

CesiumJS
1

Hi there,

I am pretty new to Cesium and I'm a bit puzzled here... for my atlas of the moon I set the globe to Cesium.Ellipsoid.MOON, but an ellipse on the globe is drawn at the wrong position. If I use the default Cesium.Ellipsoid.WGS84 everything is displayed correctly.

The Cartesian3.fromDegrees() seems to work correctly as its radius matches the radius of the ellipsoid. Any help is welcome!

  var feature = viewer.entities.add({
    position: Cesium.Cartesian3.fromDegrees(lng - 180, lat, 0.0, scene.globe.ellipsoid),
    id: id,
    name: cap,
    description: txt,
    ellipse: {
      semiMinorAxis: max,
      semiMajorAxis: min,
      fill: false,
      outline: true,
      outlineWidth: 1.0,
      outlineColor: Cesium.Color.YELLOW,
      rotation: dir
    }
  });

2

Hello,

I wasn’t able to reproduce this error. Here is the example I tested with:

var ellipsoid = Cesium.Ellipsoid.MOON;
var viewer = new Cesium.Viewer(‘cesiumContainer’, {
globe: new Cesium.Globe(ellipsoid)
});

var greenCircle = viewer.entities.add({
position: Cesium.Cartesian3.fromDegrees(-111.0, 40.0, 0.0, ellipsoid),
ellipse : {
semiMinorAxis : 300000.0,
semiMajorAxis : 300000.0,
material : Cesium.Color.GREEN
}
});

``

Let me know if you still can’t get your ellipse to draw correctly. We don’t have great support for non-earth ellipsoids, so I wouldn’t be surprised if you do find other issues.

Best,

Hannah

3

Thanks for your quick response. The ellipse is still drawn incorrectly, but a label is drawn at the correct position. However, in sandcastle your example works fine...

For now I upscaled the moon to a WGS84 ellipsoid, I will downscale it to a custom ellipsoid at some later stage and try to find the cause then.

4

So apparently there are three places you need to pass your custom ellipsoid to.
See the discussion in this issue for more information and a workaround that might help avoid other issues: https://github.com/AnalyticalGraphicsInc/cesium/issues/4245

-Hannah