Load geojson from IONASSET and create entity

General
1

Is there some example code to load a geojson multipolygon file from ion asset and put it in an entity so that colours and styles can be modified ( similar to the Texas example in Sandcastle).
The polygons form curved planes above the ground (not terrain)
I have tried it, but it just loads as the default polygons colours.
Cesium.IonResource.fromAssetId(287424)
Thanks,

2

Here is an example of loading multipolygon GeoJSON (not from Cesium ion, but you can just replace the hard coded GeoJSON data with your asset.

Example.

3

Thanks,

So is this the correct way to refer to the asset?
const geojson = Cesium.IonResource.fromAssetId(276924);
My test polygons appear in the Cesium ion, but not in the Sandcastle.

4

@QuartzReservoir that line basically loads the URL from which to load the GeoJSON. To load it from ion and add it to the viewer you need to:

// Load the GeoJSON file from Cesium ion.
  const geoJSONURL = await Cesium.IonResource.fromAssetId(your_asset_id);
  // Create the geometry from the GeoJSON, and clamp it to the ground.
  const geoJSON = await Cesium.GeoJsonDataSource.load(geoJSONURL, { clampToGround: true });
  // Add it to the scene.
  const dataSource = await viewer.dataSources.add(geoJSON);

This code snippet is from this tutorial: Visualize a Proposed Building in a 3D City | cesium.com

5

Thanks Omar,
My polygons load from ion and now appear on the terrain,
Keith

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