Error: All attribute lists must have the same number of attributes

I’m trying to show an ellipsoid for some sattelite communications to a base station and I’m getting the above error. It appears that there is a limit of about 38,000km for the radii of an Ellipsoid. Is this a bug or a deliberate limit?

Here’s a simple repro in sandcastle:

const viewer = new Cesium.Viewer(“cesiumContainer”);

viewer.entities.add({
name: “Top and bottom cut out”,
position: Cesium.Cartesian3.fromDegrees(-102.0, 40.0, 140000.0),
ellipsoid: {
radii: new Cesium.Cartesian3(39000000.0, 39000000.0, 39000000.0),
innerRadii: new Cesium.Cartesian3(3.0, 3.0, 3.0),
minimumCone: Cesium.Math.toRadians(60.0),
maximumCone: Cesium.Math.toRadians(140.0),
material: Cesium.Color.DARKCYAN.withAlpha(0.3),
outline: true,
},
});

viewer.zoomTo(viewer.entities);

Since I could find no obvious limits, I was able to make the example work by increasing the number of slicePartitions to 141. Could be something going on with Earth intersection calculations.

Increasing the slicePartitions to 146 brings the problem back, some kind of edge condition

I have reported this as a bug on the cesium repo here Large ellipsoid causes DeveloperError: All attribute lists must have the same number of attributes. · Issue #10903 · CesiumGS/cesium (github.com)