I can see a lot of useful advantages on being able to import terrain. It would make it much easier to model roads that fit the first time, have exact flat pad spot for special buildings, and tunnels, all fitting the terrain as it was modeled in the model program.
I would like to see this ability also. But as tomjscott mentioned, it would be almost useless if npc cant walk on it. The editor would have to be able to import it just like the terrain is now, and it would need to function collision wise the same.
So yes I would like this also in time.
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