3D Tiles debug tools: bounding spheres are not displayed

[jailln]

Your Environment

• Version used: 2.38.2
• Browser Name and version: Firefox and Chrome
• Operating System and version (desktop or mobile): Linux

Context

3D Tiles debug tools "bounding box" checkbox does not work for 3D Tiles tilesets with bounding spheres. There is no error in the console. It is limiting for debugging such tilesets.

Steps to Reproduce (for bugs)

1. Create an example with a 3D Tiles tileset with bounding spheres (e.g. https://storage.yandexcloud.net/gis-3d-models/data/tiles3d/Valaam_Aerial_Survey/Scene/Cesium.json from Unstable 3d tiles rendering in itowns #1859) and with a 3D Tiles debug UI (e.g. debug.create3dTilesDebugUI(menuGlobe.gui, view, tileset, d);)
2. Zoom to the tileset. Camera position for the above-mentioned tileset:

        var placement = {
            coord: new itowns.Coordinates('EPSG:4326', 30.950135, 61.395949, 0),
            range: 3000,
            tilt: 22,
        }

4. Check the "Bounding box" checkbox

Expected Behavior

Bounding spheres should be displayed (the code exists but I don't know if it ever worked ?).

Actual Behavior

Nothing is displayed.

[mgermerie]

The complete 3d-tiles support is planned in the short term road map. We are currently studying possibilities in terms of libraries to enhance support (as mentioned in #1917).