Insula — a design study for a modern isometric city builder
Insula
The best city builders made you responsible for a decision you could see. Then the sequels hid the working. This is an argument about what to put back, made out of cities that actually run.
Take out a road
Every house here depends on somebody walking past it
The market does not supply the houses near it. It sends a person out along the roads, and she serves whoever she walks past before her legs run out. That is the 1998 rule, unchanged. Take out one tile and watch which houses stop being on her way.
One — the walker
A ring and a fork, built from the same fourteen houses
Same market, same well, same temple, same three gardens, same fourteen houses. More road on the fork, and a city less than half the size — because eight steps of the walker’s budget are spent getting to the junction and most of the rest getting back out of the arm she chose. The ring holds 322 people; the fork holds 200. Supply-by-radius has no equivalent of this — a radius has no wrong answer.
What is new. In the original she rolled dice at that junction. That is not difficulty, it is unfairness: a city that failed on a bad roll teaches nothing. Here she prefers the road she has not walked yet — still a rule you can read off the map, still punishing the fork, but now a plan is worth making.
Two — the field
Desirability is a property of the land, so draw it on the land
One straight street, so every walker reaches every house: market, well and temple, both ends, no exceptions. The only thing that differs is the field — a foundry at one end, a row of gardens at the other. The west houses are stuck as shacks and hovels. The east houses climb to terraces and a villa. Nothing but the ground is different.
The original had this rule and buried it under an overlay you had to leave the city to open. Blue where the land is unwanted, warm where it is, underneath the buildings rather than on top of them — because you need it while you are deciding where to build, not afterwards when you are working out what went wrong.
Three — the ladder
A house should tell you the one thing it is waiting for
- Tentnothing yet4
- Shackland nobody minds living on7
- Hovela well within walking distance11
- Insulaa well and a market20
- Terracea well, a market, a temple34
- Villaall three, on land worth wanting52
Six rungs, not twenty. The original had far more and the extra ones were mostly a slower drip of the same feeling. What matters is that the ladder runs both ways: take the well away and the villa becomes a shack again, visibly, from the rooftops, with no panel open.
What is new. Every house can say, in one line, the single thing between it and its next rung — no well reaches it, or four short on desirability. One thing to go and fix, never a list of everything it lacks. That sentence is the entire difference between a simulation you learn and one you look up.
Should this exist?
Nothing is being sold and there is nothing to sign up for. The next thing to build is the sandbox — a city you actually lay out rather than three that make a point each — and it is only worth a month if enough people want it.
The numbers this page is actually running
A market walker has twenty-six steps, a temple twenty-two, a well twenty. She starts on a road touching her building, never leaves the road, and at every junction takes whichever way she has walked least. A house is served if it is next to any tile she walked.
Desirability radiates from buildings and falls off in a straight line to nothing at the edge of their reach: a garden gives eight over four tiles, a temple six over five, a foundry takes ten away over five. A house holds the highest rung whose services all reach it and whose desirability the tile sustains. Both conditions, every frame — which is why taking a road out can undo a villa.
The ring in the first city is twenty tiles, and the shortest-legged walker of the three — the well — has exactly twenty. Every walker laps the ring. None of them laps the fork, because a fork has to be walked twice. That is not a coincidence, it is the whole comparison, and the numbers were picked to make it exact rather than approximate.
Are these screenshots of a real game?
They are not screenshots at all. Every city on this page is a simulation running in your browser: the walker actually paths along the roads, the desirability field is actually computed from the buildings, and the houses are actually drawn at the level they can sustain. Nothing here is a mockup, which is why breaking a road changes the picture.
Is this an official remake, or connected to the original?
No. It is an unaffiliated design study by one small studio, built from scratch. No art, code, audio or data from any existing game is used or reproduced here — every shape on screen is drawn from its own footprint at runtime. The original games are referred to only to argue about their design, which is what design criticism is.
Why is there no city to build?
Because the question being asked is narrower than that, and a half-finished city builder would answer it worse than three cities that make one point each. If enough people say this should exist, the next thing to build is the sandbox. If they do not, a sandbox nobody wanted would have cost a month.
What is actually new here, rather than restored?
Three things. The walker prefers the road she has not walked instead of rolling dice, so a route is something you can plan against. Every overlay is on top of the city rather than a mode you leave the city to enter. And a house that cannot climb says the one thing standing in its way, in a sentence, instead of making you learn it from a wiki.
Why call it Insula?
It is the Roman word for an apartment block, and it is the rung in the middle of the housing ladder — the point where a shack becomes a city. The whole argument is about that ladder being visible, so it seemed like the right thing to name it after.