simcity-1989 game sourced
SimCity
The city builder in which a mayor zones residential, commercial, and industrial land, lays power and roads, and sets taxes while grid maps of land value, crime, pollution, and traffic drive where the city grows.
core loop
zone residential, commercial, and industrial land -> connect roads and power -> RCI demand and land value grow zones -> collect taxes each year -> fund police, fire, and roads -> respond to crime, pollution, traffic, and disasters
design notes
Will Wright grew the game out of the map editor he built for Raid on Bungeling Bay and drew its model from Jay Forrester's Urban Dynamics. The simulation is a set of coarse grid maps (land value, crime, pollution, traffic density, police and fire effect) recomputed in passes, plus three RCI demand valves that integrate city-wide balance; a zone grows when its local score plus the valve passes a random test. The 2008 GPL release as Micropolis made these update rules, including crime = 128 - land value + density - police effect, inspectable.
relations
17 stored edgesTreasury and budget
Tax revenue is collected periodically from population, land value, and tax rate; police, fire, and road funding fractions scale their effects, and underfunded roads decay.
Land value
Each 2x2 block's value falls with distance from the population-weighted center, rises near trees and water, and drops with pollution and high crime, clamped to 1-250.
Power grid
Zones must connect to coal or nuclear plants through power lines or adjacent zones; unpowered zones do not grow and lower the city score.
RCI demand
Three valves move by the ratio of projected to actual residents, commerce, and industry plus a tax offset, clamped to +/-2000 or +/-1500 (Micropolis source).
Zoning
The player paints 3x3 residential, commercial, and industrial zones; simulated developers build, densify, or abandon them.
Citizen satisfaction
A yearly evaluation turns problem scores into a 0-1000 rating and an approval poll.
Crime and policing
Crime per cell is 128 - land value + density minus smoothed police effect, clamped 0-250.
Data overlays
Map windows show land value, crime, pollution, traffic density, police and fire coverage, and population density.
Pollution spread
Industry and traffic write a pollution map that depresses land value and can summon the monster.
Random disasters
Fire, flood, tornado, earthquake, and a pollution-gated monster fire at 1/481, 1/241, or 1/61 per cycle by difficulty.
Scenario objectives
Time-limited scenarios such as Detroit 1972 set a goal to reach before the clock ends, added at Broderbund's suggestion.
Service coverage
Police and fire stations write funding-scaled effect values to a block map that is smoothed outward.
Taxation
One city-wide tax rate adds a positive offset to demand at low rates and a negative offset at high rates.
Traffic congestion
Zones generate trips along roads; the resulting traffic density map adds to pollution and complaints.