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Offline kierongreen

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City growth and evolution
« on: April 03, 2012, 07:10:03 AM »
I see people complaining about city growth in the 1930's to 50's, and I thought I'd make a few comments:

This was the era of mass housing estates in the UK:
Earlier in this period  people envisaged garden cities where people would be surrounded by the countryside, while railway companies (in particular the Metropolitan with Metroland) encouraged suburban growth.
In the middle of this time there was little new building due to WW2. Directly after this simple, small, pre-fabricated housing units were seen as the solution to the housing shortage.
Later on, slum clearance lead to declining population densities as tenement blocks were replaced by council housing schemes. Only the high rise tower blocks came close to matching the previous crowded inner cities - they were surrounded by open ground though. Unless you are planning on simulating a concrete dystopia.


Which leads me to a more general discussion about city evolution. I've tried playing from 1750 onwards - so far as far as 1890. Playing this I've seen that nearly all cottages and houses from the 18th century get replaced by 19th century tenement blocks. Brick terraces barely feature as their level is not as high as the stone tenements. City growth in general was far, far too rapid over this timescale so if I run the game again I might have to decrease it further...


I guess what I'm saying is that I wouldn't want 1930s flats to be the solution to city sprawl in that period - at that time, before green belt policies were introduced towns were ever expanding and taking over the countryside so I think that is actually the challenge of that time, how to economically service a lower density population. Sure there were some nice art deco blocks of flats - however at the moment if these were introduced then from experience they would be more or less the only thing to be built...


Maybe some changes are needed to the city growth code in general to better simulate evolution of towns but I'm sure this has been tried before. I'll still try having a play around with that side of things however.

Offline Milko

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Re: City growth and evolution
« Reply #1 on: April 03, 2012, 07:35:41 AM »
Hello Kierogreen

Looking at your considerations I can think of a "mediation".
If it is correct that historically the 1930-1950 era apartments are of low density, however, believe we need to insert some apartment of medium density.
The explosion of the city is remarkable. Also, if you start a game in 1930 - 1940, the program does not construct buildings of medium high density and the cities you get are huge, giving an appearance of unreality.
In my opinion, therefore, to mediate, it would be good to put some building of medium density, but without entering buildings in high density.

Giuseppe

Offline kierongreen

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Re: City growth and evolution
« Reply #2 on: April 03, 2012, 08:41:22 AM »
The problem is with the code as it is at the moment whatever the highest level building that is provided is the one that will dominate. It doesn't matter whether this is "medium" or "high" level, it will still crowd out low level buildings. Maybe changes to the code are required or maybe just tinkering with renovate percentage will fix this I don't know...

Offline The Hood

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Re: City growth and evolution
« Reply #3 on: April 03, 2012, 12:14:56 PM »
Kieron,

It's a problem I had noticed myself but not getting time to play and it's obvious relation to the exe code it isn't something I'd worried about too much to date. Given you have knowledge of the code and have played a couple of longer games yourself recently that should give you a pretty decent perspective. I'm not sure exactly how the code works but it seems to be something along the lines of:
1) decide to expand
2) use renovate percentage to determine expand out or up
3) expand central places in preference to suburbs until max level (?)

I have several ideas for changes which might improve things (no idea how easy they would be)
1) renovate percentage depends on time (to allow 1930s style suburbia and 2000s style brownfield redevelopment)
2) buildings could be flagged with an "upgrade_chance" which indicates how likely that particular building is to be redeveloped - setting this to 0
3) concentrate expansion in tiles covered by stations, and preferably link this to level of service (number of lines/frequency/capacity?) - i.e. higher levels can only be "unlocked" by having a high public transport connectivity.

From a pakset point of view, I'd be very grateful for your thoughts on how to make best use of the level= and chance= parameters at different points in the timeline as more citybuildings is moving up the priority list now.

Offline Combuijs

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Re: City growth and evolution
« Reply #4 on: April 03, 2012, 12:31:28 PM »
Quote
concentrate expansion in tiles covered by stations

This is done already. Not related to the level of service though...

Offline kierongreen

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Re: City growth and evolution
« Reply #5 on: April 03, 2012, 10:59:25 PM »
Quote
From a pakset point of view, I'd be very grateful for your thoughts on how to make best use of the level= and chance= parameters at different points in the timeline as more citybuildings is moving up the priority list now.
If there are a wider range of buildings made which fit graphically with pak128.Britain I can work out potential coding changes if required. level and chance I'm not sure can be used to simulate this entirely on their own.

Offline The Hood

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Re: City growth and evolution
« Reply #6 on: April 04, 2012, 10:34:09 AM »
OK. I think it's probably time to focus on city buildings then. What sort of things/eras do you think are the priority?

Offline kierongreen

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Re: City growth and evolution
« Reply #7 on: April 04, 2012, 11:30:07 AM »
1920s - 1960s offices
1920s - 1970s industry
1930s - 1950s high density residential
1890s - 1910s low density residential

Also the following building images I find (minor) problems with and I think would benefit from a look at:
1880 small factory, 1880 small factory-b, 80-warehouse-a, 1750-warehouse - roof texture not rotating with building rotation
1750-townhouse - windows are too big and disproportionately wide, texture too bright

If I get bored on the coding side I might have a look at some of these myself!

Offline The Hood

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Re: City growth and evolution
« Reply #8 on: April 04, 2012, 11:35:03 AM »
Thanks. Of course you are most welcome to draw things for pak128.Britain whenever you want!

Offline The Hood

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Re: City growth and evolution
« Reply #9 on: April 14, 2012, 11:02:17 AM »
I've just had a thought which might be worth a try on this. As I understand the present code, first the game decides whether to upgrade a building or not to a higher level, then, having decided to upgrade, decides on which building to go for based on the chance parameter and what it is adjacent to. This means that a high level building with low chance will always be built if an upgrade is chosen just because it is the only building to chose with that level.

Instead, how about taking chance into consideration when upgrading? That way a low chance means a low chance of ever being built, not just at that level. I'd assume this would be coded by taking chance into account before level, but I don't know the code and can't code, so...

Offline Fabio

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Re: City growth and evolution
« Reply #10 on: April 14, 2012, 01:35:39 PM »
Another thought: upgrading vs new building could change with the years using a table not unlike speed bonus or city roads.

Offline The Hood

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Re: City growth and evolution
« Reply #11 on: April 14, 2012, 05:12:30 PM »
If there are a wider range of buildings made which fit graphically with pak128.Britain I can work out potential coding changes if required. level and chance I'm not sure can be used to simulate this entirely on their own.

I've now done a load of buildings for the 1930s - how many do you need for a start?

Offline kierongreen

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Re: City growth and evolution
« Reply #12 on: April 14, 2012, 05:18:13 PM »
As many as you can give! But seriously, the more variety the better :) I'm trying to think of a good way of simulating housing estates for a start, but balancing them with a central business district would be useful...

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Re: City growth and evolution
« Reply #13 on: April 18, 2012, 09:50:03 AM »
I've just had a thought which might be worth a try on this. As I understand the present code, first the game decides whether to upgrade a building or not to a higher level, then, having decided to upgrade, decides on which building to go for based on the chance parameter and what it is adjacent to. This means that a high level building with low chance will always be built if an upgrade is chosen just because it is the only building to chose with that level.

Instead, how about taking chance into consideration when upgrading? That way a low chance means a low chance of ever being built, not just at that level. I'd assume this would be coded by taking chance into account before level, but I don't know the code and can't code, so...

This seems to be a good idea in principle, although I have not delved into the city building code, so do not know how easy that this would be.

Incidentally, may I add to Kieron's list public buildings and utilities, which could be coded as attractions (hospitals, schools, libraries, universities, workhouses, lunatic asylums, courts, water pumping stations, etc.)?

Offline The Hood

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Re: City growth and evolution
« Reply #14 on: April 18, 2012, 10:15:36 AM »
I'm not sure what to do about public buildings. As they are bigger than 1x1 a lot of the time, it makes sense to have them as attractions in the current setup, but that does mean restrictions on (1) only one per city, (2) never replaced and (3) always built on the edge of the city. If citybuildings bigger than 1x1 are allowed it may make sense for some of them to become citybuildings, or it may even make sense to allow attractions to be built on top of existing citybuildings (if they are the sort to be built in town centres). In any case I'm currently focusing on genuine citybuildings rather than attractions, so there is a greater variety of building stock to help any efforts on recoding.

And while the discussion is still in a general "wishlist" phase, it would be great if industries coded as "city" e.g. the butcher, baker etc. could be integrated into citybuilding code so (a) they align with roads and (b) they are built on high streets in town centres where possible.

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Re: City growth and evolution
« Reply #15 on: April 18, 2012, 10:37:12 AM »
I think that drawing them as attractions makes sense. Very often, these older buildings will remain for some time, and be built on what is the edge of the city when they are built. Public utilities are rarely built on expensive town/city centre land. As to only having one - one doesn't want a dozen swimming baths or scores of police stations in a medium sized town, so that makes sense, too.