Boats are more complicated than I expected, at least when it comes to Dwarf Fortress. But that's true of just about everything in Dwarf Fortress, the colony management game that more or less strives to simulate the depth of reality in ASCII text. I recently spoke with creator Tarn Adams about how he wants to build an incredibly complex magic system, simulating how the component parts of magic would work rather than generic spells. In that interview, Adams mentioned how, by aiming to teach the game's dwarves what real scholars would know by the year 1400, they ended up knowing how to measure the height of the atmosphere.

In this final part of our interview, Adams talks about why he's excited about the idea of adding boats to Dwarf Fortress, and all the complexities that would go along with them. Somehow, boats explain how he learned about the economy of medieval Europe and why dwarven personalities are broken into 50 separate traits.

Wes Fenlon, PC Gamer: Let's talk about boats a little, because your eyes lit up a little when you mentioned boats. You said boats are super cool.

Tarn Adams: Everyone loves boats. Everyone loves Pirates! with the exclamation point.

Dwarf pirates?

Yeah. We liked a lot of boat games when we were kids. There's this whole idea, maybe it's come back now, but this idea of the 'expedition' game. There are several indie ones now, but it had been dead for like 15 years, right. The games like Starflight and Seven Cities of Gold, where you prepare for your journey and you're exploring but it's not unrestricted sandbox exploring. You have to be really careful, have food, the number of crew, the supplies you decide to bring. And go out, and then return or set up somewhere else.

It's kind of fascinating what you can do when you have boats. They're a little fortress that can go on its own. I haven't even thought of what that would be like, running a fortress that's a boat on a long journey. It would be interesting to contain it.

For us, the problems are just technical at first. How do you do the directions the boats are going in ASCII? You have a few choices. I know Cataclysm: Dark Days Ahead, this zombie roguelike, they have these cars and stuff you can make and drive around, and they take the rectangle and shear it, so that it looks kind of weird, but the seats are still connected. For me, there's too many mechanics going on to kill the geometry that way. If two people were wrestling diagonally across those two car seats, when it turned they'd no longer be adjacent.

There's a million little problems like that that basically boil down to, you can point your boat in four directions. The geometry is intact. But that doesn't mean your boat needs to go four directions. You could have it going on a pretty smooth vector, up-up-over, whatever, and then the only problem becomes the pop when you get up to 45 [degrees]. Suddenly it turns. If we do pretty big boats, they might displace one tile of water. Maybe it depends on how much cargo is in there, who knows. Then when they pop, there might be fish or mer-people over here who get whacked. Do they just teleport, or get pushed? What if there's no room to push them because you're near a dock?

A 3D rendered Dwarf Fortress on water.

I feel like the problems all have solutions. There's a sliding scale of acceptability to your solution, and I think they're mostly okay. There will be some weird things where certain mer-people get scrunched. The real problem with this is if you're not controlling the boat, and you're the player, and you get scrunched. Like if a Dwarf Fortress is on the beach, you set up this whole cove where boats can come in and dock and unload stuff, all really cool stuff, right, but then you have dwarves messing around in the water and then a boat turns the wrong way and all your dwarves are catapulted out into space... There will be little problems, and we'll just roll with it.

But yeah, boats are really exciting. In terms of the adventure mode, just running some kind of Odysseus thing or Jason and the Argonauts, if we're talking about Ray Harryhausen movies, where you're just having a boat and sailing between a bunch of magically generated items and just seeing what you find out there, but having to modify your food and get supplies and take risks at each of the islands. It sounds fun.

Wes: That's a system that you clearly have in your head already, but is later on after magic, myth generation, probably a few years down the road.

Certainly. It's one of those things where, do boats come before the economy, or does the economy come before boats? Waterways change how the economy works. They're used by everyone who's got a river. They're going to use boats for economic purposes, transporting things because water transport is so cheap. So do you want to write an economy first that's all just based on land trade, or are your equations going to break down when you throw one boat into them? And the boats don't really need the economy, because you can just make a boat. Who really cares if it's used for trade at first?

We'll have property, so we'll know who owns the boat. We'll know the relationships between the crew people and so forth. Who is the captain of the boat, that sort of thing. They just won't be on a trade run that makes sense. It could make sense to them, but not to this supply/demand type thing. So probably boats before the economy, but that might just be because I like boats.

Wes: I mean, it's your game. You can make boats if you want. I'm trying to think how different that experience would be, with boats factored into the fortress, and boats in adventure mode. In adventure mode you're getting closer to that Sid Meier's Pirates! and those expedition games.

We'll have to see. It's one of those things where I'm waiting for the feel of sending your dwarf squads off the map, which is coming soon. That's kind of what it's like to send boats out. Just this feeling of having things out and about. Then maybe there'd be a possible big shipbuilding component to water-adjacent forts, even if dwarves themselves may not be big mariners or whatever.

The surface level of a fortress, via Redditor frameskip.

Certainly that cove idea sounds really fun. You get the wagons, now, but what if you got boats too? I don't know about fishing, because that's obviously something you do with a boat, too. What if half of your fortress map was just little fisherboats out there? And then they could get capsized and stove in by the great whale and that kind of thing.

Wes: You've got to code tsunamis, now. You're going to need weather systems for your boats if they're sail-powered.

Mm-hmm. And I'll have to learn a lot, too. As much as I like the games with boats, I don't know very much about them. How boats work.

Wes: When you're implementing a system like economy, for example, do you do a lot of research?

Yeah.

Wes: Are you mostly reading online, or getting textbooks?

No, I've got collected economic... I don't remember the name of the book anymore, but an economic geography of the middle ages, like three volumes. Some of it's outdated, but you can look stuff up too if you're thinking 'nah, that can't be right.' I just read the whole thing cover to cover, don't retain everything very well, but take notes, lots of notes, and come back and use some of them. Just get a better feel for things that you didn't have a really good feel for, like how important just cloth was during that period. That all of Europe was just this giant textile route involving sheep and dye and the Hanseatic league stuff .

I know more than I did before, but I'm not an economist, either.

Wes: Are there cases where your research has ended up taking your implementation of something in a totally different place than you would've initially thought it would be?

I'd say, like, every time. Pretty much. When I was doing personality research, every game developer comes across personality stuff in order, pretty much. First they see some random personality test like Myers-Briggs. Then they hit the Big Five, then if they go further and the big five aren't good enough they get the 30 facet breakdown of the big five, which is where we were.

And then you decide that's not good enough, so you start reading theology books to make your dwarves a little more traditionally evil occasionally, right, because you need to judge people, and the personality tests don't judge people. I mean for narrative purposes, I'm not saying for reality purposes. I'm saying for narrative purposes, you need to have a little more character. So we ended up with this sort of ad hoc group of 55 personality things, somewhere in that ballpark.

It's similar with everything. I didn't know any of that before I started. It's always that way.