originalNodeId

The original nodes in a Gltf get their index as originalNodeId, an optional property on the GltfNode Type.

This can be used in combination with GltfData to get all the associated info in the original gltf.

At runtime, it is only used by the skin/joint system for finding and updating the nodes that are affected by skin transforms.

For parsing, it is also used - and primitives need additional values like the originalMeshId. Since these are just simple numbers and may be useful for debugging or getting at extra stuff in the original Gltf, they are carried along through the scene even after parsing is completed.