How can i load a fbx file with attribute 'index'?

Questions
1

I’m trying to load the model and do cloth simulation on it. But I find that the loaded model(fbx file) has no attribute index(using FBXLoader). And I need the ‘index’ to do cloth simulation.

Moreover I find that all the loaders integrate the ‘position’ and the ‘index’ attributes in original file into one called ‘position’ when loading and just use ‘position’ to render the model.
So i wonder if there is any way to load model and reserve the attribute ‘index’ or there is any way to compute the ‘index’ on the loaded model. Thanks.

2

Index should be an attribute of the geometry, any chance you can share the model or a live example with the loaded model here? Using BufferGeometryUtils.mergeVertices should generate an index for the geometry in question but this may be unnecessary on inspection of the model / code you’re using…