Strategia
Chieftain
- Joined
- Jul 12, 2010
- Messages
- 71
All right, first off, I would like to extend my apologies if something very similar to this idea has been posted before. I tried using the search function, but it just threw up a whole bunch of threads for Civ IV from 2006, so I'm not 100% sure this idea is unique. Anyway.
One thing that's always kind of irked me in Civ is that population growth is tied strictly to
food production, although this was at least mitigated by 
Happiness (and 
Health in IV). However, now that Happiness has been changed to a flat empire-wide tally, that limiter is gone entirely, and with good resources nearby and diligent tile improvements city population can explode beyond belief.
However, any new city you found still starts at 1
, and its growth is based entirely on 
Food production and modifiers thereof. This can lead to situations where you have two cities, spaced far enough apart, with a highly-developed countryside and population in excess of 20 ..... and then the new city, settled in between the two, has to slowly crawl its way up from 1 while the two megalopoli are bursting at the seams just a handful of hexes away.
That got me thinking about population migration. I don't know if it's even possible to add this to Civ V, at least in the way I'll describe below, but maybe it could be slated for Civ VI, whenever that comes around. One can hope. Or maybe this thread will inspire an enterprising modder, or maybe it'll sink into deep obscurity, I don't know.
The idea I've developed so far is a fairly complex one, basically an entire new game mechanic almost on the order of things like Happiness and Faith, in that it can greatly affect the empire and has several fairly complicated interlocking mechanisms that determine what, if anything, happens. To put it in very broad strokes: The idea is that Population can migrate along 
Trade Routes in addition to growing/shrinking based on Food.
Like I just said, this mechanic would be governed by several interlocking aspects. The first one is Overpopulation; this is a city stat, probably invisible to the player (or it only appears as a number, without breaking down how it's calculated). One of the main factors for Overpopulation would of course be population itself; the larger a city, the greater the Overpopulation. Other factors would include the surrounding terrain, terrain improvements, and buildings in the city. A 20 City surrounded by hills and mountains will have higher Overpopulation than a 20 City in flat, open plains. Rivers also help mitigate Overpopulation; rivers adjacent to cities help more, the longer the better. Border size and tile improvements also reduce it; having a larger countryside and developed land to work draws people out of the city. Walls and other defensive buildings could increase Overpopulation, or more likely just escalate the pressure from population and terrain by a certain percentage; being cooped up behind defensive fortifications limits how much the city can grow and leads to slum development. This means that Cities on the border will suffer from more Overpopulation than Cities in the centre of the empire. Finally, sanitation buildings help alleviate Overpopulation: buildings like Granaries, Aqueducts, Baths and Hospitals can drive down Overpopulation, allowing you to fight it more directly.
Another factor would be, let's call it Proximity. This is an invisible stat, and is based on how difficult it is to move from one city to the next. This is where Trade Routes come in, although they're by no means the only factor. AFAIK, Civ V only considers to go from other Cities to the Capital, but for the purposes of this suggestion they also connect other Cities to each other, even if there's no connection to the Capital. Cities that only lie a few hexes from each other will obviously have a fairly high Proximity right off the bat; River connections also help, as does a shared Coast (after Sailing, obviously), and especially in the form of Roads, Railroads and Harbour connections. Two distant Cities connected via a Road will have higher Proximity than two Cities that lie fairly close together, but are separated by hills and forests, with no other connection. A coastal City with a Harbour may have more Proximity to a Harbour City on another continent than to a nearby City on the same continent with no connection. Proximity can go through other Cities too; an inland City connected to the Harbour City via will also have greater Proximity to Cities on the other continent connected to their Harbour City via than to the aforementioned close-by city with no connection. It's easier to drive a car (or ox-drawn wagon) to a port, sail to another continent, then take another car (or ox-drawn wagon) to an inland city than it is to navigate backwater country roads to some hick town in the middle of hillbilly country. Of course, Airports are the ultimate Proximity factor; a City with an Airport will always have great Proximity to a City on the other side of the world with which it is only connected via Airport, even more so than to a moderately distant City with a Road connection (or to a distant city with a Railroad connection), and two moderately distant Cities with Airports will have Proximity through the roof. There are some more detailed qualifiers; for instance, Roads through Forests and Hills will provide somewhat less Proximity than Roads over flat terrain, so that a City connected to two other Cities equally far away will have more Proximity to the one which lies across flat plains than the one on the other side of a deep, dark forest, until Bridges are developed Roads across Rivers will take a massive hit in Proximity, techs like Engineering which increase Road movement will increase Road Proximity, techs like Steam Power which increase embarked/transport movement will increase Harbour Proximity, and so on and so forth.
A third factor is Attraction. In some ways, this is the inverse of Overpopulation, but it has some mechanics of its own. Attraction determines, obviously, how much people want to live in that City. This is a fairly complex stat. The previous explanation of Proximity may have been a huge wall of text, but the underlying concept is fairly simple; the closer Cities are to each other, and the better the connection, the more people will move between them. Attraction can't be boiled down to something that simple, apart from the extremely broad "this is how attractive a city is". Attraction is governed by a wide variety of factors; high production always creates a lot of Attraction, but so does a high 
value, which could make a City with lots of buildings and Wonders, in the middle of mining country with low production, more attractive than a City surrounded by Farms with production through the roof. (The lack of food and unappealing surrounding terrain could even lead to an Overpopulation problem, if enough people move to that City because of its culture.) Space also attracts people; a City surrounded by Hills and Mountains is automatically less attractive than a City in flat, open grassland, although if the hilly City has huge borders while the grassland City is tiny, the hilly City has the advantage. Coastal Cities always attract people, and even a City with a tiny sliver of Hills backed by Mountains inland can be very attractive if it has a wide open expanse of Ocean in front of it. Terrain development draws people; farmland and lumber mills and mines are more appealing than empty, wild terrain. If is brought back, Cities with a large surplus are very attractive. Natural Wonders always draw people. Security and "exoticness" also influence Attraction; if you were at war with another Civ, Cities near that border will be less attractive, but Cities located along peaceful Borders will be more attractive. The Capital will always be a little extra Attractive than other, similar cities. And finally, jobs. If there is a lot of unworked, developed land around a City, people are drawn there to work (provided the same isn't true in all other Cities as well), and even empty Specialist slots make a City more attractive. Of course, it also matters exactly how much can be produced by the empty land/specialist slots; a small City with huge borders and lots of unworked land on a Tundra is far less attractive than a small City surrounded by unworked Mines on Hills. Raw 
output also helps attract people, even if there aren't that many job openings left; people move there hoping more jobs will appear in the future, and they could very well be right if that City is churning out buildings much faster than other Cities. This means that Cities near resources such as Iron and Stone, or surrounded by Hills, could start growing like crazy when they're connected to the Road network, as people start migrating there from all over the empire. Attraction is obviously more prone to sudden, seemingly random shifts than the other two; Overpopulation is based on count, based on production and mitigated by border growth, terrain development and building construction; Proximity is entirely based on terrain and in the form of Roads, Railroads, Harbours and Airports. Attraction, on the other hand, is influenced by many factors, some of which are entirely beyond player control. To avoid Attraction rapidly shifting up and down without player input, there is a certain inertia in this stat; Attraction changes somewhat slowly, and major factors - such as migration leading to Overpopulation, buying tiles or culture-bombing to rapidly grow borders, developing the terrain rapidly with several Workers - can take some time to fully affect Attraction, although some factors, such as a declaration of war by a neighbouring Civ or a new connection, take effect almost immediately.
I have now apparently hit my icon limit. Dammit. I just like using those, and they help break up the huge walls of text. Oh well.
Anyway, these are the three factors which govern Migration: Overpopulation, Proximity and Attraction. Now I suck at mathematics, so I can't present any example statistics or interaction formulae, but I can at least try to describe how this should work. Migration doesn't mean that entire Population units suddenly disappear from one city and reappear in another. It's more like a factor that affects city growth. If you have an Overpopulated city that's still producing enough Food to grow, and another city with a high enough Attraction, Migration means that the Overpopulated city will grow more slowly than raw Food production would indicate, while the Attractive city grows faster than it should. If the discrepancy is too great, this can mean that people are Migrating enough for the Overpopulated city to actually start shrinking, but that would require careful planning and setting up on the part of the player. In normal play, it should work as I described above; large, Overpopulated cities growing more slowly than Food production would seem to indicate, and smaller, Attractive cities growing faster than they should.
This does not mean that large cities become impossible to maintain, and that newly founded cities explode while the older cities shrink down to half size. Cities that grow to be that large will by definition be very Attractive; their surrounding landscape is well-developed, there is a Food surplus, there are plenty of buildings which draw people, there are most likely plenty of jobs, so these cities should still continue to grow. Newly founded Cities, unless they're located in already-developed land, will generally have fairly low Attraction, this being solely based on the surrounding terrain and lack of Overpopulation. Spending buckets of Gold buying buildings can help increase Attractiveness fairly quickly, obviously at the expense of aforementioned buckets of Gold. This would mean that in the scenario mentioned at the beginning of this post, the newly founded City would essentially be drawing growth from the two megalopoli; they're not shrinking, but part of their population is moving to the new city, which jump-starts that city's growth and development.
The effects of this are varied. In pure Tall empires, the handful of cities should be Attractive enough for a sort of balance to appear, with no significant long-term migration occurring, while new Cities get a huge kick-start by siphoning off growth from the sprawling, developed, Overpopulated megalopoli. If the player drops enough Gold into the new City, the older ones can experience a period of shrinkage, until a new balance is found. In pure Wide empires, it's more likely that migration will have a fairly significant effect. New Cities can potentially receive a huge bonus to growth, as each of the many existing cities contributes a small amount of migration, which can lead to a backlash as the new City becomes more Overpopulated, stops growing and starts trickling growth to the rest of the empire. A Civ just entering the Industrial Age, and building a Factory in a mining city, could see that mining city explode as migrants from all over the empire are drawn to the new jobs and high Production output, escalating the City's Production but potentially causing Overpopulation and starvation. A Civ with a well-developed homeland that's just beginning to found overseas colonies could see the homeland's growth stagnating as colonists move overseas en masse, greatly accelerating colonial development. It would also be possible, under this system, to found Cities purely dedicated to migration; large Food producers, with few amenities, could be used to force migration to well-developed cities in rough, hilly country with hardly any sources of food; the hilly city will be permanently starving, but if enough jobs are available in the mines, and enough attractive buildings are built, the population could be stabilised around a much higher level than it could otherwise attain, by attracting people from the farming cities. Shrewd players could lay out their empires so that older cities in the centre could draw people from the fringes, creating a Tall-ish empire with a wide buffer; or they could lay it out so that new border cities get tremendous growth bonuses from deliberately Overpopulated cities in the centre, slowly pushing outwards with well-developed, defensible Cities. Or it could lead to surprises, pleasant and unpleasant; a strategically located city growing very slowly because it's located in undeveloped hills and the rushbuilt defences making the city feel more Overpopulated, or old, stagnated core cities suddenly starting to grow again because a new island city has a massive Food surplus from Fish. Industrial cities with Factories will draw in large amounts of people from boring rural farming towns, but as Overpopulation (and maybe pollution) starts to press down on the workers, they could start moving away in large numbers, leaving an industrial ghost town.
I know this is a humongous wall of text, but I'm not going to give a tl;dr summary because of how complicated this idea is and how many interlocking factors it has. I'm sorry if I bored you, but please don't use that as a justification for saying "it's ****", go do something else. If you're reading this because you went through the whole text, then I thank you for your attention and ask you to please leave any comments and/or suggestions below.
One thing that's always kind of irked me in Civ is that population growth is tied strictly to
food production, although this was at least mitigated by Happiness (and Health in IV). However, now that Happiness has been changed to a flat empire-wide tally, that limiter is gone entirely, and with good resources nearby and diligent tile improvements city population can explode beyond belief.However, any new city you found still starts at 1
, and its growth is based entirely on Food production and modifiers thereof. This can lead to situations where you have two cities, spaced far enough apart, with a highly-developed countryside and population in excess of 20 ..... and then the new city, settled in between the two, has to slowly crawl its way up from 1 while the two megalopoli are bursting at the seams just a handful of hexes away.That got me thinking about population migration. I don't know if it's even possible to add this to Civ V, at least in the way I'll describe below, but maybe it could be slated for Civ VI, whenever that comes around. One can hope. Or maybe this thread will inspire an enterprising modder, or maybe it'll sink into deep obscurity, I don't know.
The idea I've developed so far is a fairly complex one, basically an entire new game mechanic almost on the order of things like Happiness and Faith, in that it can greatly affect the empire and has several fairly complicated interlocking mechanisms that determine what, if anything, happens. To put it in very broad strokes: The idea is that
Population can migrate along Trade Routes in addition to growing/shrinking based on Food.Like I just said, this mechanic would be governed by several interlocking aspects. The first one is Overpopulation; this is a city stat, probably invisible to the player (or it only appears as a number, without breaking down how it's calculated). One of the main factors for Overpopulation would of course be population itself; the larger a city, the greater the Overpopulation. Other factors would include the surrounding terrain, terrain improvements, and buildings in the city. A 20
City surrounded by hills and mountains will have higher Overpopulation than a 20 City in flat, open plains. Rivers also help mitigate Overpopulation; rivers adjacent to cities help more, the longer the better. Border size and tile improvements also reduce it; having a larger countryside and developed land to work draws people out of the city. Walls and other defensive buildings could increase Overpopulation, or more likely just escalate the pressure from population and terrain by a certain percentage; being cooped up behind defensive fortifications limits how much the city can grow and leads to slum development. This means that Cities on the border will suffer from more Overpopulation than Cities in the centre of the empire. Finally, sanitation buildings help alleviate Overpopulation: buildings like Granaries, Aqueducts, Baths and Hospitals can drive down Overpopulation, allowing you to fight it more directly.Another factor would be, let's call it Proximity. This is an invisible stat, and is based on how difficult it is to move from one city to the next. This is where
Trade Routes come in, although they're by no means the only factor. AFAIK, Civ V only considers to go from other Cities to the Capital, but for the purposes of this suggestion they also connect other Cities to each other, even if there's no connection to the Capital. Cities that only lie a few hexes from each other will obviously have a fairly high Proximity right off the bat; River connections also help, as does a shared Coast (after Sailing, obviously), and especially in the form of Roads, Railroads and Harbour connections. Two distant Cities connected via a Road will have higher Proximity than two Cities that lie fairly close together, but are separated by hills and forests, with no other connection. A coastal City with a Harbour may have more Proximity to a Harbour City on another continent than to a nearby City on the same continent with no connection. Proximity can go through other Cities too; an inland City connected to the Harbour City via will also have greater Proximity to Cities on the other continent connected to their Harbour City via than to the aforementioned close-by city with no connection. It's easier to drive a car (or ox-drawn wagon) to a port, sail to another continent, then take another car (or ox-drawn wagon) to an inland city than it is to navigate backwater country roads to some hick town in the middle of hillbilly country. Of course, Airports are the ultimate Proximity factor; a City with an Airport will always have great Proximity to a City on the other side of the world with which it is only connected via Airport, even more so than to a moderately distant City with a Road connection (or to a distant city with a Railroad connection), and two moderately distant Cities with Airports will have Proximity through the roof. There are some more detailed qualifiers; for instance, Roads through Forests and Hills will provide somewhat less Proximity than Roads over flat terrain, so that a City connected to two other Cities equally far away will have more Proximity to the one which lies across flat plains than the one on the other side of a deep, dark forest, until Bridges are developed Roads across Rivers will take a massive hit in Proximity, techs like Engineering which increase Road movement will increase Road Proximity, techs like Steam Power which increase embarked/transport movement will increase Harbour Proximity, and so on and so forth.A third factor is Attraction. In some ways, this is the inverse of Overpopulation, but it has some mechanics of its own. Attraction determines, obviously, how much people want to live in that City. This is a fairly complex stat. The previous explanation of Proximity may have been a huge wall of text, but the underlying concept is fairly simple; the closer Cities are to each other, and the better the connection, the more people will move between them. Attraction can't be boiled down to something that simple, apart from the extremely broad "this is how attractive a city is". Attraction is governed by a wide variety of factors; high
production always creates a lot of Attraction, but so does a high value, which could make a City with lots of buildings and Wonders, in the middle of mining country with low production, more attractive than a City surrounded by Farms with production through the roof. (The lack of food and unappealing surrounding terrain could even lead to an Overpopulation problem, if enough people move to that City because of its culture.) Space also attracts people; a City surrounded by Hills and Mountains is automatically less attractive than a City in flat, open grassland, although if the hilly City has huge borders while the grassland City is tiny, the hilly City has the advantage. Coastal Cities always attract people, and even a City with a tiny sliver of Hills backed by Mountains inland can be very attractive if it has a wide open expanse of Ocean in front of it. Terrain development draws people; farmland and lumber mills and mines are more appealing than empty, wild terrain. If is brought back, Cities with a large surplus are very attractive. Natural Wonders always draw people. Security and "exoticness" also influence Attraction; if you were at war with another Civ, Cities near that border will be less attractive, but Cities located along peaceful Borders will be more attractive. The Capital will always be a little extra Attractive than other, similar cities. And finally, jobs. If there is a lot of unworked, developed land around a City, people are drawn there to work (provided the same isn't true in all other Cities as well), and even empty Specialist slots make a City more attractive. Of course, it also matters exactly how much can be produced by the empty land/specialist slots; a small City with huge borders and lots of unworked land on a Tundra is far less attractive than a small City surrounded by unworked Mines on Hills. Raw output also helps attract people, even if there aren't that many job openings left; people move there hoping more jobs will appear in the future, and they could very well be right if that City is churning out buildings much faster than other Cities. This means that Cities near resources such as Iron and Stone, or surrounded by Hills, could start growing like crazy when they're connected to the Road network, as people start migrating there from all over the empire. Attraction is obviously more prone to sudden, seemingly random shifts than the other two; Overpopulation is based on count, based on production and mitigated by border growth, terrain development and building construction; Proximity is entirely based on terrain and in the form of Roads, Railroads, Harbours and Airports. Attraction, on the other hand, is influenced by many factors, some of which are entirely beyond player control. To avoid Attraction rapidly shifting up and down without player input, there is a certain inertia in this stat; Attraction changes somewhat slowly, and major factors - such as migration leading to Overpopulation, buying tiles or culture-bombing to rapidly grow borders, developing the terrain rapidly with several Workers - can take some time to fully affect Attraction, although some factors, such as a declaration of war by a neighbouring Civ or a new connection, take effect almost immediately.I have now apparently hit my icon limit. Dammit. I just like using those, and they help break up the huge walls of text. Oh well.
Anyway, these are the three factors which govern Migration: Overpopulation, Proximity and Attraction. Now I suck at mathematics, so I can't present any example statistics or interaction formulae, but I can at least try to describe how this should work. Migration doesn't mean that entire Population units suddenly disappear from one city and reappear in another. It's more like a factor that affects city growth. If you have an Overpopulated city that's still producing enough Food to grow, and another city with a high enough Attraction, Migration means that the Overpopulated city will grow more slowly than raw Food production would indicate, while the Attractive city grows faster than it should. If the discrepancy is too great, this can mean that people are Migrating enough for the Overpopulated city to actually start shrinking, but that would require careful planning and setting up on the part of the player. In normal play, it should work as I described above; large, Overpopulated cities growing more slowly than Food production would seem to indicate, and smaller, Attractive cities growing faster than they should.
This does not mean that large cities become impossible to maintain, and that newly founded cities explode while the older cities shrink down to half size. Cities that grow to be that large will by definition be very Attractive; their surrounding landscape is well-developed, there is a Food surplus, there are plenty of buildings which draw people, there are most likely plenty of jobs, so these cities should still continue to grow. Newly founded Cities, unless they're located in already-developed land, will generally have fairly low Attraction, this being solely based on the surrounding terrain and lack of Overpopulation. Spending buckets of Gold buying buildings can help increase Attractiveness fairly quickly, obviously at the expense of aforementioned buckets of Gold. This would mean that in the scenario mentioned at the beginning of this post, the newly founded City would essentially be drawing growth from the two megalopoli; they're not shrinking, but part of their population is moving to the new city, which jump-starts that city's growth and development.
The effects of this are varied. In pure Tall empires, the handful of cities should be Attractive enough for a sort of balance to appear, with no significant long-term migration occurring, while new Cities get a huge kick-start by siphoning off growth from the sprawling, developed, Overpopulated megalopoli. If the player drops enough Gold into the new City, the older ones can experience a period of shrinkage, until a new balance is found. In pure Wide empires, it's more likely that migration will have a fairly significant effect. New Cities can potentially receive a huge bonus to growth, as each of the many existing cities contributes a small amount of migration, which can lead to a backlash as the new City becomes more Overpopulated, stops growing and starts trickling growth to the rest of the empire. A Civ just entering the Industrial Age, and building a Factory in a mining city, could see that mining city explode as migrants from all over the empire are drawn to the new jobs and high Production output, escalating the City's Production but potentially causing Overpopulation and starvation. A Civ with a well-developed homeland that's just beginning to found overseas colonies could see the homeland's growth stagnating as colonists move overseas en masse, greatly accelerating colonial development. It would also be possible, under this system, to found Cities purely dedicated to migration; large Food producers, with few amenities, could be used to force migration to well-developed cities in rough, hilly country with hardly any sources of food; the hilly city will be permanently starving, but if enough jobs are available in the mines, and enough attractive buildings are built, the population could be stabilised around a much higher level than it could otherwise attain, by attracting people from the farming cities. Shrewd players could lay out their empires so that older cities in the centre could draw people from the fringes, creating a Tall-ish empire with a wide buffer; or they could lay it out so that new border cities get tremendous growth bonuses from deliberately Overpopulated cities in the centre, slowly pushing outwards with well-developed, defensible Cities. Or it could lead to surprises, pleasant and unpleasant; a strategically located city growing very slowly because it's located in undeveloped hills and the rushbuilt defences making the city feel more Overpopulated, or old, stagnated core cities suddenly starting to grow again because a new island city has a massive Food surplus from Fish. Industrial cities with Factories will draw in large amounts of people from boring rural farming towns, but as Overpopulation (and maybe pollution) starts to press down on the workers, they could start moving away in large numbers, leaving an industrial ghost town.
I know this is a humongous wall of text, but I'm not going to give a tl;dr summary because of how complicated this idea is and how many interlocking factors it has. I'm sorry if I bored you, but please don't use that as a justification for saying "it's ****", go do something else. If you're reading this because you went through the whole text, then I thank you for your attention and ask you to please leave any comments and/or suggestions below.
