Interiors are DTS Shapes.
Interiors and DTS shapes are about as different as you can get in the world of 3D modeling. Converting between the two is definitely possible, but with the exception of very simple models, it's going to require quite a bit of editing by hand.
Going from an interior to a dts shape is pretty easy but will produce stuffty models unless you edit them, because there's a bunch of extra bits on interiors that something like a dts shape doesn't need. In fact, interiors are just compiled versions of map files, which are literally text files containing the coordinates of the vertexes of 3D shapes, and you could even make one using notepad.
Going from a dts to an interior is pretty difficult and I don't think there will ever be an automated way of doing it since you have to slice up a bunch of concave meshes into convex, closed solids. A computer would have to guess how you meant to close up the meshes if they're not closed (like a sail, piece of fabric, etc), which side is supposed to be the inside and which is supposed to be the outside, then run through an iterative process trying to find the most efficient way to divide up the meshes without producing broken, concave, of mircrobrushes. Any model produced using this method would probably have tons of stuff at weird angles that would be extremely unfriendly to manual editing or texturing.
DTS shapes will make absolutely stuffty interior maps. I know people will try anyway, but I've seen maps based on DTS shapes before and they were stuffty. I'm not talking about any of the unreleased proofs of concepts people have been working on. Back in the days of blockland v0002, there were dts based maps, and they sucked. People didn't divide up the map into chunks correctly so the collision mesh was broken and you could shoot through any part of the map. Vehicles were extremely unstable on them and would fall through them far more frequently than they would on interiors or even bricks. They didn't interact with fog or view distance very well and on large ones you would generally just see the whole thing regardless of the fog or view distance. They also don't light like interiors, so the lighting on them looked like ass. Finally, they don't have all the optimization that interiors do, so you can't put as much detail into them and they'll put a lot more stress on a computer than an interior.
DTS shapes are absolutely, without a doubt, the
wrong way to go for map making in Blockland's future. It's like deciding to hold hot coffee in your cupped hands because you're all out of clean mugs. It is physically possible to do so but you're going to get burned because you're not using the right tool for the right job. Anybody who tells you otherwise is absolutely wrong and you should link them to this post so they can discover why for themselves.
