Upgrade 3D Tileset with composite (cmpt) tile to 1.1 - attribute data missing

I’m trying to upgrade an existing 3D Tileset from 1.0 to 1.1.

1] 1.0 tileset

The 1.0 tileset has a composite tile (cmpt) with 2 instanced models (a tree and a box in I3dm’s), of each model there is 1 instance.

Demo see: https://bertt.github.io/cesium_issues/gpu_instances_metadata/10

Tree on island (left) has attributes: oas=PW-000168, city=PALAU

Box in the sea (right) has attributes: oas=PW-000028, city=KOROR PS

2] Upgrading from 1.0 to 1.1

Using the following command the tileset is upgraded to 1.1 :

$ 3d-tiles-tools upgrade -i ./10/tileset.json -o 11 -f --targetVersion 1.1

Latest version of 3d-tiles-tools is used here

3] 1.1 Tileset in CesiumJS

When inspecting the resulting tileset in CesiumJS (see https://bertt.github.io/cesium_issues/gpu_instances_metadata/11/) both instances have the same attributes ( oas=PW-000028, city=KOROR PS)

tree:

box:

4] Expected behaviour

Expected behaviour is the instances have different attributes (like before the upgrade).

5] Remarks

This could be an issue somewhere in the 3d-tiles-tools upgrade tool or in the client (CesiumJS). But when inspecting the resulting tileset GLB I don’t observe any wrong pointers (the attribute data of the tree is available), so I’m inclined to suspect CesiumJS more (like only the first propertyTable is used?).

I only quickly looked over this for now (and will have to allocate some time to inspect the data more thoroughly, and try out the conversion).

But the last sentence…

sounds oddly familiar: It reminded me of EXT_mesh_features extension ignoring my class/table definitions, always looking up in propertyTable at index 0 · Issue #11683 · CesiumGS/cesium · GitHub .

(Maybe you can say from the tip of your head whether that would fully explain the observed behavior. Otherwise, it may be necessary to investigate this further)

yes that looks like it!

so its a known issue… hopefully it can get more priority as it’s a showstopper when using multiple instanced models with 3D Tiles 1.1