Error in UE 5.1

Cesium for Unreal
1

After aligning, modeling, and texturing drone-captured images in Reality Capture, I exported it in Cesium 3D Tiles(*.json) format and tried to load the resulting file as a URL in Unreal Engine 5.
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However, I received an error message and need help resolving the issue.

The error message:
LogCesium: Loading tileset from URL file:///C:/Users/undtw01_user/Documents/Tileset/L0/tileset_test.json
LogCesium: Loading tileset from URL file:///C:/Users/undtw01_user/Documents/Tileset/L0/tileset_test.json done
LogCesium: Error: [2023-04-12 18:51:54.959] [error] [ErrorList.h:72] Failed to load file:///C:/Users/undtw01_user/Documents/Tileset/L0/tileset_test/Geometry/lod13_0.b3dm:

  • Error when parsing tileset JSON, error code 3 at byte offset 0

What should I do to troubleshoot this problem?

2

That’s a strange error. Maybe the .b3dm file is malformed, because that error code corresponds to an invalid character in the JSON file.

If you have CesiumJS cloned on your machine, you can use the local version of Sandcastle to test if the tileset loads successfully. Otherwise, we would have to look at the tileset ourselves to try and figure out the issue.

3

Some tools - and Reality Capture may be one - like to export all the files pre-compressed with GZIP. When accessing them locally, there are no HTTP response headers to indicate that this is the case, and so Cesium for Unreal is unable to correctly interpret them. There may be an option in Reality Capture to not GZIP. Or, you can manually ungzip all the files after they’re exported.