HTTP 403 when loading textures provided by iModel Mesh Export API

[r-veenstra]

What happened?

When using the iModel Mesh Export API, loading textures result in the following errors. I'm guessing this is due to the query params containing the cloudfront signature info not making their way through to the texture request? Same tilesets are ok in CesiumJS.

Url data anonymized as this bug is from private data- reach out for a testing sample.

LogCesium: Warning: [2025-04-09 07:27:43.157] [warning] [TilesetContentManager.cpp:663] Warning when resolving external gltf buffers from https://blah.cloudfront.net/redacted/mesh.glb?sv=mysv&spr=https&se=myse&sr=c&sp=rl&sig=mysig&Policy=mypolicy&Key-Pair-Id=mykeypairid&Sig
nature=mysignature:
- Could not load the external glTF buffer: https://blah.cloudfront.net/redacted/textures/texture.png
- Errors while loading external glTF buffer: https://blah.cloudfront.net/redacted/textures/texture.png
- Request for https://blah.cloudfront.net/redacted/textures/texture.png failed with code 403

Environment

Cesium for Unreal version: 2.14.1
Unreal Engine Version: 5.4.4
Operating System: Win 11

Reproduction steps

1. Load an iModel Mesh Export API tileset that uses textures (reach out for a valid URL)
   ...

Supporting evidence

No response

[j9liu]

Thanks for the report @r-veenstra! Sorry to bother, but could you check if this works any better on v2.15.0? One of the fixes in cesium-native v0.46.0 was to properly resolve external data for glTFs, so that might be relevant here.