When you plan on additively loading scenes, then you need to line of the terrain blocks, right? I use L3DT to generate my terrains, and that can break large areas into tiles. Is that how people create multiple scenes that link seamlessly?
I know about SetNeighbors() to link terrains, but don’t the terrain edges already have to match each other?
Bump. I would also like to hear the answer to this.
Cutting a large terrain image into tiles is probably the only way to handle additively-loaded terrains, unless the terrain is being generated procedurally. For example, if you were using Perlin noise (not necessarily a good way to do it) you could arrange it so an edge of the new terrain was copied from the opposite edge of the old terrain.
You could perhaps discuss this on Wish List or file a feature request if you would like to see enhanced terrain modelling features in Unity.