What are the different Smoothing options (Normal Only, Face, Edge) of the FBX output? - Basics & Interface - Blender Artists Community

I’m practicing to export my meshes to an FBX file in Blender and import them into the game engine. Sometimes mesh smoothing turns out not as expected, so I got curious about the difference between the smoothing options. I’ve looked through the manual, but the Geometry\Smoothing option is written in TODO, so I’m at a dead end.

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