Chrae Games

City

Build a city in 3D in your browser: zone residential, commercial and industrial land, lay roads, run power, water and garbage, fund fire, police, schools and hospitals, climb nine population milestones that unlock new buildings, and watch demand, land value, traffic, pollution, crime and your budget respond every month. Everything is generated and simulated on your device.

This tool needs JavaScript to run. Nothing is sent to a server — it works entirely in your browser. The code is open source: view it on GitHub.

About City

A city builder in the SimCity tradition, rendered in 3D from nothing but code. The map, every building and every vehicle are generated on the fly, and underneath runs a detailed statistical simulation: residential, commercial and industrial demand by wealth tier, desirability per tile, land value, air and water pollution, crime, fire risk, traffic assignment over your road network, power, water and rubbish collection, service coverage, city ordinances and a monthly budget. Nine population milestones unlock buildings and pay a grant, every troubled building shows what it is missing, and the city lives in this browser tab only.

  • Zoning with three densities and three wealth tiers per zone type. Buildings grow, upgrade, change wealth and get abandoned based on demand and how desirable the tile is, and the inspector lists exactly what a lot needs for its next level.
  • A milestone ladder from Outpost to Megalopolis: each population tier unlocks buildings, denser zoning, avenues, loans or policies and pays a cash grant, so a first city teaches itself.
  • Thirty-one facilities: wind, coal, gas, solar, hydro and nuclear power, pumps, towers and a treatment plant, landfill, incinerator and recycling centre, fire and police stations and headquarters, clinics and a hospital, schools, a library and a university, parks, a plaza, a bus depot, city hall, a stadium and a landmark tower.
  • Power, water and garbage as real networks: plants, pumps and collection facilities feed connected tiles, a shortfall causes brownouts, dry lots or rubbish piling up, and floating icons over buildings say which of eight problems each lot has.
  • Traffic assigned every month over the road graph with congestion feedback; buses take cars off the streets, avenues carry more, and eight ordinances trade a monthly cost for less crime, cleaner air, fewer fires or more shoppers.
  • A monthly ledger with tax rates per zone, service funding, loans and policies, an advisor that points at the problem holding the city back, fourteen data views with legends, city statistics with 30-year graphs, and a day/night cycle with lit windows.

Frequently asked questions

How does the simulation work?

The city is a 128 × 128 grid of tiles. Every tick the simulation updates a set of per-tile layers: desirability, land value, pollution, crime, fire risk, utility and service coverage, traffic and commute time. Buildings grow or decay from those layers and from city-wide demand for each zone type and wealth tier, and once a month taxes are collected, services are paid for, demand is recomputed and milestones are checked. It is a statistical model in the style of the classic SimCity games, not one that tracks individual citizens.

Why does nothing grow?

Zones need a road within three tiles, power, and (for medium and high density) water. Industry also needs a road that reaches the edge of the map so goods can leave. Turn on the problem icons or click a building with the inspect tool: it lists what is missing and how to fix it, and the advisor names the most likely city-wide cause.

How do I unlock more buildings?

Grow the population. Each milestone (400 residents for a hamlet, 1,200 for a village, 3,000 for a town and so on up to 100,000) unlocks a bundle of buildings and features and pays a grant. Locked tools show the tier they need, and the milestones panel lists the whole ladder. Nothing is ever locked again if the population later drops.

Is the 3D scene downloaded from somewhere?

No. There are no models or textures; the terrain, buildings, roads, trees and vehicles are built from code in your browser. The only download is the three.js rendering library, which loads once when you open the page.

Where is my city saved?

In this browser only, automatically at the end of every month and when you leave the page. Only the layers you changed are stored; the terrain is rebuilt from the seed. Clearing site data deletes the city.

Does it run on a phone?

Yes, on any device with WebGL. On a touch screen one finger pans and two fingers zoom and rotate; turn on the paint toggle to apply the selected tool with a single finger drag.