geosolutions-it#10758: Support for Cesium Ion Terrain Provider

docs/developer-guide/maps-configuration.md

@@ -1232,6 +1232,24 @@ The `terrain` layer of `cesium` type allows using Cesium terrain format complian
 }
 ```
 
+##### Cesium Ion terrain provider
+
+The `terrain` layer of the `cesium-ion` type enables the use of Cesium Ion terrain format-compliant services (i.e., Cesium Ion resources). The options attribute allows for the configuration and access of Ion resources and their associated assets.
+
+```json
+{
+  "type": "terrain",
+  "provider": "cesium-ion",
+  "visibility": true,
+  "options": {
+    "assetId": "", // cesium ion asset id to be requested
+    "accessToken": "", // cesium access token to be used
+    "server": undefined, // resource from the Cesium ion API server. Defaults to https://api.cesium.com when unspecified
+    "credit": "" // optional, additional credit to be displayed along side credit and attribution from ion resource
+  }
+}
+```
+
 #### Elevation
 
 This layer provides information related to elevation based on a provided DTM layer. **It does not provide the terrain profile for 3D visualization**, see [terrain](#terrain) layer type for this feature.

web/client/components/map/cesium/plugins/TerrainLayer.js

@@ -26,6 +26,20 @@ function cesiumOptionsMapping(config) {
     };
 }
 
+function cesiumIonOptionsMapping(config) {
+    const options = config.options ?? {};
+    return {
+        ...(options.assetId && {
+            url: Cesium.IonResource.fromAssetId(options.assetId, {
+                accessToken: options.accessToken,
+                server: options.server
+            })
+        }),
+        credit: options.credit,
+        requestMetadata: options.requestMetadata
+    };
+}
+
 const createLayer = (config, map) => {
     map.terrainProvider = undefined;
     let terrainProvider;
@@ -42,6 +56,10 @@ const createLayer = (config, map) => {
         terrainProvider = new Cesium.EllipsoidTerrainProvider();
         break;
     }
+    case 'cesium-ion': {
+        terrainProvider = new Cesium.CesiumTerrainProvider(cesiumIonOptionsMapping(config));
+        break;
+    }
     default:
         terrainProvider = new Cesium.EllipsoidTerrainProvider();
         break;
@@ -61,7 +79,8 @@ const createLayer = (config, map) => {
 const updateLayer = (layer, newOptions, oldOptions, map) => {
     if (newOptions.securityToken !== oldOptions.securityToken
     || oldOptions.credits !== newOptions.credits
-    || oldOptions.provider !== newOptions.provider || oldOptions.forceProxy !== newOptions.forceProxy) {
+    || oldOptions.provider !== newOptions.provider
+    || oldOptions.forceProxy !== newOptions.forceProxy) {
         return createLayer(newOptions, map);
     }
     return null;