There are two competing schools of city-building mechanics. It's not like PC vs. Mac, but each city-builder falls into one of these camps, and has since time immemorial.
In one corner is SimCity and its buddies. Over here the important thing is zoning. The enterprising city planner pays money to zone plots on the map. Eventually, little people will build their houses and businesses in these plots. City services such as fire houses and police stations work by extending their influence over vaguely circular areas.
In the other corner is Caesar and its buddies. In this paradigm the important thing is walking distance. The king plops don houses and businesses, and the people who live and work in the city walk from place to place in order to get things done. City services work by dispatching officials to trouble spots.
Cities XL is definitely in the first camp. There is nothing wrong with this, it just means that one shouldn't expect any revolutions in the genre from this game.
So how does it all work out? Reasonably well, actually. The gamer starts with a patch of land, a bunch of money, some zoning laws, and a song in his heart. The first thing he must do is build a road, then zone for some industry and housing. Nothing new for the hardened SimCity mayor.
But wait! This is where things start to get different. The zoning tool allows for three different zoning shapes. Square zones allow you to specify a square area to zone. and it will lay down the required roads. The freestyle tool lets you lay out the zone as an irregular n-gon by using multiple clicks (again auto-placing roads). The single-plot placement tool allows you to lay down a single plot, but does not build the required road.
This brings up the first oddity of Cities XL – infrastructure. There are no water pipes or electric lines or the usual utilities, at least not in the usual manner. You can build them, but they serve as export commodities – your citizens don't need them. On the one hand, this spares you a lot of micromanagement, on the other hand it takes away some of the “planning” aspect of “city “planner”. This is a persistent feature of the design decisions that went into Cities XL – like SimCity, but with the complexity turned down. At least bridges are still a pain to lay out.
The developer, Monte Cristo, is headquartered in Paris (I envision guys in turtlenecks sitting in a loft smoking clove cigarettes; the secretary is a babe) so that means a European class system. There are 4 separate classes of housing you can zone – Unqualified, Qualified, Executive and Elite (and three densities – low, medium and high). Each type has different demands – basically, higher classes require more (and more expensive) city services. With all these classes, why is there never a revolution? SimFrenchRevolution would rock.
So why zone for those expensive elites? Well, different types of business require different types of citizens. Simple, low-density heavy industry can get by with just unqualified workers, but more profitable, less polluting high tech industry will need and elite workers. Since the city makes money from business taxes (which more profitable businesses pay more of) and personal taxes (which better-earning citizens pay more of) you will definitely want these high-maintenance, high-productivity, highly-paid citizens in your town.
There is one other way to make money. Trade. After some time your heavy industry (or other industry type) will make more stuff than your local economy can absorb. This can hurt profitability unless you open up the possibility of trading with the outside world. In single-player this is easy – there is only one company “outside” to trade with. It pays lousy, but it's better than nothing.
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