How to get USDZ or DAE model units?

How do I retrieve the units (e.g., centimeters, meters) for a USDZ or DAE model file in SceneKit?

I've tried to use SCNSceneSourceAssetUnitKey as follows, but I never get any values returned.

RealityConverter seems to show the units for USDZ files before export and when I look at a DAE file XML it seems to have the correct metadata, but I've not found any way to retrieve it. Is it broken or is there another method (e.g., Model I/O)?

Code Block
if let modelSource = SCNSceneSource(url: url, options: options) {
NSLog(" units = \(String(describing: modelSource.property(forKey: SCNSceneSourceAssetUnitKey)))")


How to get USDZ or DAE model units?
 
 
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