>>299419559
There are a couple procedural generation maps out there yeah. You have full access to the unity Mesh interface, so you can generate triangles and UVs. However, you don't have access to Texture, so you'll have to do your texture generation in shaders (which is generally more efficient anyway than cpu texture gen).

You won't have access to dynamic unity terrain either, which is mainly a bummer if you want decent terrain collision (e.g. for vehicles). So you'll need to assemble the collision geometry from primitives as well.