Georeferencing a 360° sphere GLB — 3D_MODEL tiling fails at 9% when position is set

Cesium ion
1

Hi all,

I’m tiling 360° panorama spheres (GLB from Blender, panorama on the sphere’s inner surface) into 3D Tiles via the ion REST API, and I’m stuck on a tiling failure when I try to georeference them.

Asset creation request:

POST /v1/assets
{
“name”: “test-asset-10.jpg”,
“type”: “3DTILES”,
“options”: {
“sourceType”: “3D_MODEL”,
“position”: [46, 24, -80]
}
}

(position = [longitude, latitude, height].)

What happens:

Options Result
sourceType: “3D_MODEL” + position Upload OK, then tiling ERROR at 9%
sourceType: “3D_MODEL” only Tiling COMPLETE, but non-georeferenced (no root.transform)

GET /v1/assets/{id} only reports “status”: “ERROR”, “percentComplete”: 9 — no error detail.

This worked for us earlier (we got proper georeferenced tilesets with root.transform placing the model on the globe); it started failing after a pipeline update around Feb 2026, which makes me think the handling of position for 3D_MODEL changed.

Questions:

  1. Is position still valid for sourceType: “3D_MODEL”? If it changed/was deprecated, what’s the current way to place a model at a lon/lat/height during tiling?
  2. Could an inward-facing sphere (degenerate/unusual geometry for a “real-world model”) be the reason the georeferencing path fails while the plain path succeeds?
  3. Is there any way to retrieve the detailed tiling error message via the API rather than the dashboard?

Any guidance appreciated — happy to share the GLB. Thanks!