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Hi there, you city builder aficionados! Once again it is the time for another exciting story from the pages of developer diaries. I am your humble host, Henkka, and I am here to talk about zoning. So, gather around by the fire and let your imagination fly...

Oh, and in case you missed the previous entry to the dev diaries, here it is: Dev Diary 1: Roads.

Basics of zoning (or "Why zoning instead of manually placing all buildings?")
If the roads are the bones of the city, then the zones are the meat around the bones. Very early on in the development process it was clear that we wanted the game to feature a zoning tool instead of placing the myriad of the regular buildings manually. With zoning the player's job is to rule where the different types of buildings appear but it is the citizens' (that is the game's) job to actually move in and build the new houses, shops and factories, all according to the different needs of the city. The player can determine what the city requires and when by using the RCI indicator in the GUI.

While discussing the possible ways to build a city a few ways emerged: placing buildings individually and zoning. While individual placing of buildings seemed interesting and in theory allowed the player to create the exact city they wanted it became clear that creating large cities would be difficult and cumbersome. The sheer amount of buildings needed to place would turn the game into an editor rather than a city builder. Also problems would arise with the needs of the city conflicting with the artistic visions of the player: the player would want to build 10 tenements in an area while the game calculated the city required only 3. Communicating this kind of information that is always changing as the game progresses would be impractical. And as the city grows and new technological levels are reached, the player would need to manually upgrade all the buildings in the city which in the end would mean going through thousands upon thousands of buildings.

Zoning on the other hand simulates more closely city planning on the higher level where the city planners lay down guidelines and rules for citizens and companies to work in. We decided that zoning is the way to go in a game of this scale. And clever city planners can take advantage of the various zoning tools and have more control over the zoneable buildings than just painting large areas if they so choose. For example, instead of zoning the full depth of the zone grid (4 cells) the player can zone thinner slices, like 2 cell deep areas, that spawn smaller building fitting the 2 cell deep restriction.

Zone types
Cities: Skylines features three main categories for zoning: residential, commercial and workplaces. All three are divided into two types, low and high density for residential and commercial, and industry and offices for workplaces.

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Residential areas are the backbone of your city. Detached houses such as the ones on low density residential zones are inviting to older people and families with kids. High density residential apartment buildings on the other hand serve the needs of younger adults who value cheaper living costs among other things.

Each zone type serves different groups of citizens even though some overlapping occurs. For example, low density residential building are favored by families with young children and seniors while high density buildings are favored by young adults and families with no children. Low and high density commercial building work in a similar way: different citizen groups choose one zone type over the other if both are available in the city and can be accessed by good road connections.

While most of the workplaces are in the industrial and office zones commercial zones create workplaces as well even though their main function is to sell goods to citizens and accept goods deliveries from local industry. The first to unlock in the workplaces is the industrial zone which creates factories of all sizes according to workplace demand. Industrial efficiency is connected to the quality of workforce (workers' education) as well as their ability to ship goods they produce and if all the stores and shops in the city have full storages industry can stagnate until the issue is solved by providing new businesses or outside connections to ship their goods to. Offices, just like the high density residential and commercial zones, unlocks later in the game when the city is able to provide workers who are adequetly educated to perform in those jobs.

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Zoning some high density commercial areas.

Zoning tools
In Cities: Skylines there are various tools for zoning, each having its uses.

Fill tool lets the player zone large areas on one click. This tool is especially useful with city blocks of small and medium sizes since it can fill them on one go.

Marquee tool allows the player to click and drag an area of their choosing and zone huge areas at once. The margquee tool aligns itself with the grid if the drawing of the area starts next to a zone grid.

The game also features two zoning brushes, a small and a large brush. With these brushes the player can paint zoned areas. The only thing that needs to keep in mind is that the zones have to reach the road or otherwise the buildings won't spawn.

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Large zoning brush in action.

Building leveling – Residential
Each zoned building has a level. This refers to the education level of the inhabitants, the land value in the neighborhood and the services available close by. As the citizens are educated and the overall quality of life increases with new city service offerings, the buildings gain levels. Lower levels have fewer requirements, for example they require only some of the city services. Lower levels on the other hand have bigger negative impact on the surroundings from polluting factories to residential buildings generating more garbage. The highest levels require full city service coverage as well as great commercial and workplace connections to keep up their standard of living.

Building leveling – Commercial
Similarly to residential buildings commercial buildings require that their neighborhood is at a suitable standard to level up and be able to offer services to higher level citizens (level 1 has general stores while level 3 has designer shops and so on). In most cases the bonuses granted by the presence of city services and the high enough land value will eventually lead commercial buildings to achieve conditions to level up. Unlike residential levels, commercial and industrial buildings with higher levels require workers with higher education. Almost every workplace has some level 0 jobs but in order to get the most out of a 3rd level workplace it requires staff with proper levels of education.

Building leveling – Industrial / Office
Workplaces like industrial buildings and offices level up when the surrounding conditions are met. Land value plays an important role for achieving higher levels and worker education levels are equally important to be able to run the businesses after said leveling has happened. Industry in particular experiences drastic changes when reaching highest level: goods produced are of the highest quality and pollution which is a trademark of lower level factories and such is a thing of the past.

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Offices don't create pollution which is why they can be safely zoned next to a residential area.

Offices unlock at a later stage since they require even more educated personnel to be functional. Once the player reaches this level and is able to really start educating their citizens with the higher level of schools they can choose to switch to office workplaces instead of industry on the expense that it might not create as much tax income as the more polluting yet profitable regular industry.

- Henkka also known as an artist, designer and level designer at Colossal Order
 
I feel like the solar power plant is way too small. In reality they're this huge:

solar_power_tower.jpg


This is something that concerns me, as well as the airports you showed off some weeks ago, they both look "toyish" and that's not good for this game. Remember, you're making a great game, don't miss out on these scale things!

Yeah i agree, a common drawback of having a large international airport outside a city is the sheer size of the thing.

Same for powerplants and wind turbines to power a whole city, you need gigantic amounts of energy which you simply can't get in a powerplant that is not much bigger than a house.

German coal powerplant :

1280px-Scholven_Powerplant.jpg

(okay that's the largest coal plant in europe/world)

Or alternatively a coal powerplant lost in the middle of oklahoma :
GRDA-CFC-Aerial.jpg


Having large power plants in your city should be a big deal.


Also you have to bring the actual coal from somewhere, it doesn't appear out of thin air.
 
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In CIM2 they had buildings that offered both residences and jobs; I don't think that's the problem. If I understood the devs correctly the problem is having mixed use buildings satisfy both commercial and residential demand. I think they can do only one or the other.
 
I remember hearing somewhere that skyscrapers will be placed manually. What Skylines is calling high density may in fact be more in line with medium density, with then high density skyscrapers placed by the player as reward-type buildings. Could someone from Colossal clarify?

This can be true. On the screenshots you can not see any skyscrapers, so maybe high density it's not so high buildings, maybe look like medium density, or skyscrapers can be only when building has level 5 and not every building can has so high level - only some. If is true, then I'm happy
Colossal please explain !:)
 
Having giant power plants might be realistic but at the same time, the amount of room we have on the map is finite. A lot of people wouldn't be pleased to lose a huge chunk of the map to build their power plant. Something like you guys are suggesting should be left to the modders imo.

Well I sure hope we can purchase power from outside sources.
 
Having giant power plants might be realistic but at the same time, the amount of room we have on the map is finite. A lot of people wouldn't be pleased to lose a huge chunk of the map to build their power plant. Something like you guys are suggesting should be left to the modders imo.

First, the devs have already said that Skylines will have fairly large maps. The buildings do not have to be as big as their real-life counterparts, but they should be big enough to feel big. A dinky little coal furnace doesn't feel like a soot-belching monster; it feels like a dinky little furnace.

Second, good city-building games are about tradeoffs. There should be a viable tradeoff between importing electricity (or sewage services or what have you) and building your own infrastructure to handle the city's needs. There's no good reason land use should not be part of that tradeoff.
 
Just like with Sim-city, I really wish there were hybrid buildings allowing a more diversified urban planning, such as residential buildings with a few commercial ventures on the ground floor, or large skyscrapers with a mix of office and condo levels, and a shopping mall in the basement. I think it would give a much more natural feel to the game.
 
Really the solar plant should be 200m^2 for every mW of capacity. This is assuming it is at the equator with a high conversion efficiency of 20 precent (most only get a 15% efficiency). The wind turbines should also generate more like 4mW assuming optimal placement rather than the 16mW they show in the video.
 
http://en.wikipedia.org/wiki/Gated_community
And this is only the most obvious of all measures to be taken. There are a lot of ways to regulate the composition of your citizens.
Uh, that's not the government dictating where people can live, even remotely. Gated communities are essentially just high-wealth areas. It's not dictated by the government what kind of houses you can build in them or who can live there. They have a high value because they're secure.
 
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You never heard of "social" building or whatever it is called in the relevant country? That's where western country put their poor in. Any area around it see its value decreased etc...
Right, those are government built buildings. They're not saying to private citizens "you can't build here because you're too rich now go away" they're building houses and putting people who need social housing in them. If you want to make a ploppable "social housing" building and have it lower the surrounding land value then fine, but that's not what is being proposed.
 
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New approach? As per real life (well in my city anyway) planning laws assign 'zones' but the also assign 'overlays'. Why cant we have 'overlays' as well in the game?

How would overlays work?
- Overlays would be essentially a rule covering an area which controls some universal parameter (e.g. building height, Wealth Level)
- How would you view and place them? Just like zones however there can be more then one 'overlay' on a single tile.

I would also vote to make power plants / STPs / airports bigger and less toy like
 
0Fb4tz2.png

Large zoning brush in action.
From the looks of it, it looks like you can zone residential right in front of commercial and vice versa. I know dual buildings are not in the game, so what would this lead to? Small houses in the front and small stores in the back? Also, the zones look like they don't always have to be rectangular. What would those building look like?
 
Considering the fact that we know very little about the district system and that it's already been confirmed that we have some control limiting the size of buildings in an area by only painting so many squares deep in a grid, I'd say we might have the tools necessary to create suburbs and such. I'm going to wait to hear about districts before I lose any sleep over this.
 
Do not force us to have empty tiles and space between the buildings just ebcause we dont build straight roads !
I dont want to have useless empty grass fields between my buildings :excl:. Implement something to fill them. Take a loot at Cities XL
 
Thanks for all the feedback, we are eager to hear it! The choice for only high and low density was made because we felt a realistic city can be pictured with just these two zones with the different levels they have and they offer enough variation for interesting gameplay. You could for example have the city center be high density residential of high level with high rises, then have a ring of lower level high density, and make outskirts with low level low density to have normal detached houses. Citizens can live in any level of housing and won't abandon it due to not leveling up, so you can have all levels present in a city.

We are currently looking into scaling some city service buildings up, but they won't be realistically sized, because you would then need to dedicate a whole map piece for just solar power plant.

For the spaces between the curved roads the game offers decorations that you can place in empty spaces to make the city look more finished. At this moment we are going with the separate houses, because the curved roads still look nice and with the amount of map space available work pretty well in my opinion.
 
Thanks for all the feedback, we are eager to hear it! The choice for only high and low density was made because we felt a realistic city can be pictured with just these two zones with the different levels they have and they offer enough variation for interesting gameplay. You could for example have the city center be high density residential of high level with high rises, then have a ring of lower level high density, and make outskirts with low level low density to have normal detached houses. Citizens can live in any level of housing and won't abandon it due to not leveling up, so you can have all levels present in a city.

We are currently looking into scaling some city service buildings up, but they won't be realistically sized, because you would then need to dedicate a whole map piece for just solar power plant.

For the spaces between the curved roads the game offers decorations that you can place in empty spaces to make the city look more finished. At this moment we are going with the separate houses, because the curved roads still look nice and with the amount of map space available work pretty well in my opinion.
Will you be able to fill the gaps in with paving and plazas and such?
 
Thanks for all the feedback, we are eager to hear it! The choice for only high and low density was made because we felt a realistic city can be pictured with just these two zones with the different levels they have and they offer enough variation for interesting gameplay. You could for example have the city center be high density residential of high level with high rises, then have a ring of lower level high density, and make outskirts with low level low density to have normal detached houses. Citizens can live in any level of housing and won't abandon it due to not leveling up, so you can have all levels present in a city.

How do we control it?
 
Paving is available in the game. To control leveling, you just don't provide some areas with what they need to level up. For example keep the land value low by not placing parks and have low education by not providing schools. I personally think it's a fairly realistic mechanic, if a "bad neighbourhood" would get excellent services and beautiful surroundings, it would change into a more valuable area, attracting more educated and wealthier people.