We've had the cog model forever. And can interact with it, has inventory, has collision, used to even be able to pick it up. And now we have moving carts we can ride.
Why don't we have moving ships? I'm sure making it ridable is doable if we can do it with carts and horses/moose. And Custodian had a video of a moving ship years ago so it's been figured out before.
Since water is a little weird, I am guessing the tile height is not at 0.0 but at the terrain under it. Swimming checks if you are under 0.0 height, maybe that could be a way to limit where you could sail? Riding a horse does terrain checks to see if too steep to move so it shouldn't be (in theory?) too much different.
Any thoughts? Pointers? Reasons why it's just hardcoded or not doable?