Heatmaps are a core mechanic in New Cities, and actively drive the development of a city. While real life heatmaps simply visualize data, New Cities heatmaps affect which buildings can develop and the cost of Amenities. This means that heatmaps like Density and Value will increase before high density or high value buildings are built. That is to say New Cities heatmaps drive development, rather than reacting to it.
Many Amenities directly affect the heatmaps, such as the Small Park increasing local Value. Heatmaps may also be affected by traffic and Zoned buildings. In addition, all heatmaps have an affect on at least one other heatmap, as explained by Lone Pine;
|“||The game is based around six “heatmaps”. The heatmaps are Pollution, Crime, Education, Prosperity, Value, and Density. Essentially, Education (plus a good road system) creates Prosperity, Prosperity (among other things) creates Value, and Value (plus Prosperity) creates Density. However, Density creates Crime and Pollution, which have a negative impact on Prosperity and Value, creating a negative feedback loop.||”|
Pollution represents reduced air quality in an area, from Industrial smoke and automobile exhaust, but also exhaust from homes and retail establishments. Pollution is a direct result of Density and Traffic, meaning downtown areas will develop lots of pollution if nothing is done to mitigate. Certain buildings, such as those in the Industrial Zone, produce pollution independent of their Density or any traffic in the area. Some Amenities directly increase Pollution.
Pollution in an area can be reduced by any Amenities with the Nature effect; primarily Parks. Amenities with the Environmentalism effect will also ease Pollution for the entire city.
Crime represents illegal activities in an area which reduce safety and property values. Crime is caused by Density, but even low-density residential areas will have some degree of crime if no Law or Community amenities are placed nearby. Crime is increased by some Amenities, such as the Dorm Tower or Stadium, but can be mitigated by Amenities with the Law, Community, Order, or Health effects, including Police Stations, Clinics, Social Services, the Hospital, the Courthouse, the Jail, and the University Safety Center.
The Law and Community Amenity effects reduce Crime in an area, while the Order and Health effects reduce Crime for the entire city. Order does this by increasing the effectiveness of Law, rather than reducing Crime directly, so Order is only effective where you have Law-providing Amenities.
Education represents what level of education citizens in an area hold, but also the reach and effectiveness of your educational Amenities like Schools, Libraries, and the Technical College or University. Education also seems to be provided in small amounts around Retail, though it's unclear whether this is an effect of businesses in Retail zones, or a feature of increasing Prosperity and Density.
Prosperity represents a healthy economy, in which citizens are employed and trade money for goods and services. Prosperity is increased by Education, or by building road systems that connect citizens to Retail and jobs, and connect Retail to supply and customers.
Value reflects the wealth of citizens or businesses in an area, and is associated with desirability. Along with Density, it is one of only two Heatmaps to affect which building designs are chosen. Value is increased by Prosperity, as well as land value (Coasts and Hills contribute positively to Value).
Value can be indirectly increased by increasing Prosperity, meaning it is indirectly increased by Education as well. Value is directly reduced by Pollution and Crime, so reducing these with Nature and Law will preserve or increase value in an area. Amenities with the Community effect, in addition to reducing crime, directly improve Value. Many Amenities directly increase Value as an effect, including most Parks, Fancy Dorms, and the Mayoral Mansion. However, Amentities which could be considered undesirable may have a direct negative effect on Value as well.
Density affects the density of buildings that spawn in an area, as well as creating visual effects like pavement and sidewalks. Along with Value, it is one of only two Heatmaps to affect which building designs are chosen. Density is the most important Heatmap in the game, as it is directly associated with the game's victory condition, the Skyscraper (a Density 9 Office Zone building).
Density is increased by Value and Prosperity, but increases Crime and Pollution in the area. A number of Amenities, including the Pavilion, Dorm Tower, City Hall, and Convention Center directly increase the Density in an area. However, consider that Amenities which contribute Value, Education, Law, and Propsperity will also indirectly increase Density.
Density is also increased by good traffic flow through an area. Your arterials connecting to major employment centers will develop Density as a result. The Retail zone also reliably increases Density in an area, and can be used to jumpstart denser development.
Certain Amenities and Zones require a minimum Density. For zones requiring minimum Density, roads can be zones even if the threshold isn't met, meaning players may be confused when no buildings develop, despite the presence of demand. The two zones that will not develop below a threshold density are Mixed Use and Industrial (Factory).
The Traffic infoview is found in the Query menu along with the other Heatmaps, and displays data in a manner similar to conventional Heatmaps; however, unlike every other New Cities Heatmap, the Traffic map simply reports data, rather than having a direct affect on the game.
The Traffic infoview shows car positions by their headlights, and highlights roads based on traffic, which brighter (yellower) colors indicating more traffic. According to Lone Pine, the formula for traffic is the average time of recent traversals (ie, how long each car took to cross the road) divided by the estimated time it would take if there were no traffic and the cars were driving the speed limit. So a road with lots of through traffic but no slowdown should not be highlighted.