Is it possible to render a position map, similar to the one Substance Painter can generate? Or if not, would it be possible to add?
Sure that should be pretty straight forward to add. What you are asking for is per vertex positions per pixel.
Do you have any additional information on the properties of the map? Settings, format, etc.
As far as I can see, Substance just exports it as a normal (Normal as in regular) image which you can then use for other stuff (mostly, in conjuction with a worldspace normal map, to map textures using a triplanar method, to get rid of texture seams). So if you were able to save the image using the regular methods you have in the format options you have for other maps, that should be fine.
As for properties, it has some options related to normalization (Box / Sphere, so I'm guessing some kind of projection method), and limiting of axis (It defaults to baking all axes, but you can choose to only bake one, with a selector for which one you want to bake).
Hope this is helpful.
It is very helpful. Thank you very much. I’ll do some additional research now.