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I spent a lot of time investigating SC2K. I came to the conclusion the game was fundamentally flawed, due to limitations in the transport simulation. The game

I spent a lot of time investigating SC2K. I came to the conclusion the game was fundamentally flawed, due to limitations in the transport simulation. The game simulates "trips" emerging from each zone type, and a sufficient number of those trips need to reach particular other types of zone, for the origination zone to be successful. However, at each junction, the trip randomly selection one of the routes. So if you build, say, a round-about, or a subway system which is a loop with branches, it's death and ruin; trips have no idea where they should get off (this branch leads to industry, for example), and some trips just keep going round and round until they reach their max travel distance and fail. You could show this issue clearly by building a square block of road tiles - each tile then having four junctions. Traffic would go into this, and never emerge. In other words, the transport simulation is too different to real life to be playable. You had to build your transport system to fit the simulation method, if you wanted a viable city.

lopis 4y ago
[flagged]
- smcl 4y ago
  This doesn't seem related to the flaw that was described at all - it seems like it applies equally to both road and rail. So while Sim City is very US-centric ("zoning" felt like just a gaming construct to me and I was very surprised it existed in real life) it sounds like they just flubbed the pathfinding a bit.
  - nivenkos 4y ago
    Zoning exists outside the USA, sometimes implicit in planning permission.
    - smcl 4y ago
      That's probably right but, at least where I grew up, it's not something you'd know about unless you are building your own house. And it's a bit more flexible than "this bit here is residential, and this separate bit here is commercial" - these things can be mixed.
      - nivenkos 4y ago
        Yeah, mixed is really common for commercial in Europe for example. But heavy industry is still zoned for sure.
      - Sharlin 4y ago
        But in the game you’re playing a city planner (well, a very idealized, pluripotent, undemocratic version of one), so surely it should feature concepts fundamentally relevant to a city planner’s job, even if those concepts are not necessarily familiar to a layperson! Games are typically meant to educate too, after all. That said, yes, the lack of mixed zoning is one of the more unrealistic parts of city builder games, and one of the most often requested features in the Cities: Skylines community. However, it should be noted that separation of functions is a notion very fundamental to the modernist (1930s–) school of urban planning, and this originated from the entirely reasonable desire to genuinely improve the human condition in cities by separating residential areas from a polluting industry. Because single-use zoning, together with the ideal of a single-family house for everyone and the use of personal automobiles for transport, turned out to be unsustainable in more ways than one, and because polluting industry is now relegated to a Someone Else’s Problem, mixed use has become (or is becoming) fashionable again, with current ideals and best practices in planning clearly diverging from those of the modernist era. Another unrealistic idea is, of course, that of a city designed from the ground up, which, although there are indeed real-world examples of fully planned cities, they are very rare. Many players do prefer to start with a tabula rasa in these types of games, and it’s of course much less work for the developers to create maps devoid of existing human population. I, for one, would love to see more maps where the starting point is an existing town, or a group of disjoint villages scattered on the map! Nb. the notion of planning as a profession emerged in the West mostly during the 19th century, before which cities had, for the most part, grown more or less organically. The need for central planning was in many cases precipitated by fires which could easily destroy neighborhoods or entire towns. Building fire-resistant cities in the era of predominantly wooden buildings necessitated measures such as firewalls between adjacent buildings, streets wider than the alleys of old, and separating neighborhoods with wide, tree-lined esplanades or boulevards. Conveniently, the destruction left by fires also provided the opportunity to realize these measures when rebuilding.
wartron 4y ago
Sounds like art imitating life.
CalRobert 4y ago
Ultimately it was a game more than sim. Note the lack of parking lots.
BinaryRage 4y ago
Same for SimCity 2013, except the flaws extended to every agent. I've always thought that's why they limited the city size so heavily. Such a shame, because there was so much promise there. Power, water, etc. randomly chose a direction at a junction, so even basic grid would make it impossible to power a building on the other side of the city, even if the power demand was there https://www.youtube.com/watch?v=tvq6zAMJfOU https://www.youtube.com/watch?v=tvq6zAMJfOU. Traffic and pedestrians were attracted to available houses/work, but randomly every day, rather than having a defined home/work location. I built a pedestrian heavy city and would watch crowds of pedestrians head for the nearest available house on a street, before the whole street filled, and they turned around for the next nearest. Same for work, shopping, despite there being plenty available.
- ptmcc 4y ago
  SC 2013 was such a let down after so much hype, for so many reasons. As a lifelong Sim-anything fan it was crushing. Cities Skylines seems like the successor to SimCity, but even that has some deep-rooted flaws in traffic management and agent flow. Some mods exist to help coax it a bit, but it's still just a broken approach at scale. Traffic and routing is hard, I get that, but there has to be a better way. Building a city around the routing flaws is not that much fun.
  - standardUser 4y ago
    Cities Skylines can provide among the best city sim experiences to be had if you're willing to invest a day (or two) modding it to within inches of its life. That and 32gb of RAM
    - mrguyorama 4y ago
      Is there a list somewhere of "Essential" mods?
      - lp0_on_fire 4y ago
        The CitiesSkylines subreddit has a list that contains (IMO) a good number of useful and essential mods. Word of warning: if you're one of those people that likes to install a lot of mods keeping everything up to date and non-conflicting can be an pain the rear. There is, of course, a mod to keep track of which mods are out of date or could cause issues, but that's really a band-aid on top of a larger problem. The game is old enough now that many popular mod authors have long been abandoned their projects or otherwise moved on so you end up with things like "MyPopular Mod" and "MyPopular Mod UPTODATE" or "MyPopular Mod FORKED" or "Use this instead of MyPopular Mod". If I take a few weeks / months between plays this usually ends up with me having to take 30 minutes to an hour to get the mods up to date and tested. Not a huge amount of time, but when your gaming time is limited it's something to take into account.
matzf 4y ago
So these ant-like cars were supposed to be more than just decoration?
b0afc375b5 4y ago
Are there any SimCity-like games you would recommend? Or any comments on Cities: Skylines perhaps?
- albertzeyer 4y ago
  In Cities Skylines, each agent, each car actually does perform path planning. You can inspect the planned path of each car, and also follow it.
  - onli 4y ago
    Skylines (which I liked) still has weird simulation errors. Like how many ships arrive at ports, which is an ever-changing amount and has no or little relation to the real transport demand. And the amount of trains using a train line depends on the number of stations, meaning outgoing train lines always need to be connected to a single one to not overflow. How single agents path is also weird, like how much they walk. I think I remember that homes were also not persistent? When separating city blocks completely fires would not get extinguished. Either the fire station assigned is random, or only a few actually can send cars out. Which breaks down in a city not fully connected by streets. Haven't played for a few years now (last run was with the industries dlc), but also haven't read about patches adressing such issues.
    - brailsafe 4y ago
      I ultimately gave up on skylines because I kind of broke my city and it got really tiresome to try and repair or start over. Tried a few mods to greater or lesser success but they just revealed other flaws. For example, whichever mod allowed for more realistic population densities; you'd have 700 families in a residential building or w/e, but no clue where they work, and likewise in the reverse. I somehow can't click on an office tower and see what the geographic distribution of occupants is, only those that are currently commuting. I'd also get strange issues like some of my subway lines inexplicably being totally vacant no matter what I did. It's also an incredibly inefficient game to run.
epups 4y ago
Can you explain this a little bit more? Are you saying that the game actually simulates each vehicle trip individually, and then decides on a random path at every intersection?
- hypertele-Xii 4y ago
  RollerCoaster Tycoon does the same, guests wander aimlessly around park and interact with whatever they come across while considering their needs. The Sims displays the other end of this spectrum, where agents path deliberately (while still considering their needs), and the difference in simulation scale is immense. Simple fact is, pathfinding is a performance bottleneck that hasn't been solved yet. We are still using algorithms from the 1960s, and no hardware acceleration exists. SimCity has always been more of a spreadsheet with houses on top.
  - eru 4y ago
    You can do a lot of shortcuts with the pathing, because you are doing a lot of pathing on a graph that doesn't change much from frame-to-frame.
    - chongli 4y ago
      Exactly. The only time you should be calculating paths is after the player places new roads. Repeatedly calculating paths on a fixed graph is a huge waste of time!
      - db48x 4y ago
        It’s even easier than that since each agent only needs to plans a path once, when they start their trip. After that they are simply following a cached path, removing road segments from it as they go. Most games will simply not recalculate those paths when you change the network, because it causes a lag spike every time the player makes a change, and because most routes wouldn’t end up changing. Better to just have cars ignore roads that didn’t exist when they departed, and have them vanish if they need to take a road that has since been deleted.
dncornholio 4y ago
Does the city really get influenced by what junction a car or person would take? Weren't these objects just for visuals?
- casenmgreen 4y ago
  In SC2K, you do not see cars or people. I do not know if in the later versions, there is a correlation between visually depicted cars/people and trips (or if trips are used at all, although from what people are writing here, it seems they are).
  - smcl 4y ago
    You do see a representation of the traffic, but yeah definitely not individual vehicles
tetha 4y ago
Interesting. This is similar to a common optimization in the genre of city builders with walkers, like Caesar or Pharaoh. In these games, buildings like a market or a temple spawn walkers, which walk on roads and distribute services and goods to tents and houses they walk past. An important optimization in these games is to avoid crossroads and junctions, because walkers tend to randomly choose a direction at junctions. This would make it a coin flip which of the two roads would get food or religious services, possibly causing all kinds of chaos. One of the best layouts as far as I recall was just a big block with a circular road going around it, because this forced the walkers to walk past all buildings in the block reliably.
- casenmgreen 4y ago
  Exactly. This is what you end up having to do in SC2K. You must direct the traffic, by not offering junctions.
- lelandfe 4y ago
  Heads up that the Pharaoh remake released today: https://store.steampowered.com/app/1351080/Pharaoh_A_New_Era/ https://store.steampowered.com/app/1351080/Pharaoh_A_New_Era...
  - neura 4y ago
    Saw this. Really looking forward to checking it out for the very topics being discussed here. I love looking at how different teams implement these details. Is it just faked enough to be visually pleasing or do they really have each visual actor in the world doing the real work. :D Used to love playing with these details in the old version of Pharoah and Caesar.
saberience 4y ago
Are you arguing that a game in 1993 is flawed because it failed to accurately simulate a city populated with 100k+ people and associated cars and infrastructure? I think if you assumed such a thing in the first place your premise and assumptions were massively flawed. You're saying the game isn't playable because it was too different to real life? Did you notice the Superhero who arrives to fight natural disasters or the giant aliens who can invade? Or the fact that you can magically position fire "trucks" where you want instantly?
- taink 4y ago
  The flaw isn't that it is not realistic enough, but that it goes too much against an average human's preconception of how a basic traffic system should work. It is absolutely not unreasonable to expect a 1993 game to not choose a random route at a junction; it should use a basic pathfinding algorithm (which were well-known, even in 1993) to choose the closest one. Of course it is limited by performance but optimization is hardly a good counter-point to intuition in this kind of game.
  - phkahler 4y ago
    What if the flawed routing simply exaggerates flaws with the way we think it should be designed? The number one bottleneck in real traffic is intersections. Some people think optimal city design should mix zoning types at a finer level. To your point though, we can't really demonstrate what's better when the agents are acting stupidly. I'd like to be able to learn what would work in the real world too.
    - BlueTemplar 4y ago
      Yeah, also it is not clear to me why is that so bad, so what that you have a circle line, wouldn't only a microscopic fraction of paths get stuck on it after a large number of crossroad steps ?
  - mrguyorama 4y ago
    This game was meant to run on a 25mhz 386 and 4mb of RAM. Complex pathfinding and over-complicated sub-simulations would have drastically limited how large of a city you could build before your system just stopped working.
treeman79 4y ago
https://youtu.be/NTJQTc-TqpU https://youtu.be/NTJQTc-TqpU Someone that spent years building an optimized city. Six million residences.
mysterydip 4y ago
At least in the original simcity, as a path was made it was pushed to a stack. If the route didn't reach a destination, the stack was popped and intersections tried again. At least that's what I get from these https://lively-web.org/users/Dan/uploads/SimCityReverseDiagrams-1.pdf https://lively-web.org/users/Dan/uploads/SimCityReverseDiagr... Was this changed in 2k?
- bombcar 4y ago
  The original SimCity has (IIRC) checks to see if services were available and ways to estimate traffic load, later ones tried to simulate actual trips. So it went from “can this house reach a job” to “simulate this house driving to work” - the difference comes from a high density doing one check to doing multiple.
deleted 4y ago
[deleted]

lopis 4y ago

[flagged]

smcl 4y ago
This doesn't seem related to the flaw that was described at all - it seems like it applies equally to both road and rail. So while Sim City is very US-centric ("zoning" felt like just a gaming construct to me and I was very surprised it existed in real life) it sounds like they just flubbed the pathfinding a bit.
- nivenkos 4y ago
  Zoning exists outside the USA, sometimes implicit in planning permission.
  - smcl 4y ago
    That's probably right but, at least where I grew up, it's not something you'd know about unless you are building your own house. And it's a bit more flexible than "this bit here is residential, and this separate bit here is commercial" - these things can be mixed.
    - nivenkos 4y ago
      Yeah, mixed is really common for commercial in Europe for example. But heavy industry is still zoned for sure.
    - Sharlin 4y ago
      But in the game you’re playing a city planner (well, a very idealized, pluripotent, undemocratic version of one), so surely it should feature concepts fundamentally relevant to a city planner’s job, even if those concepts are not necessarily familiar to a layperson! Games are typically meant to educate too, after all. That said, yes, the lack of mixed zoning is one of the more unrealistic parts of city builder games, and one of the most often requested features in the Cities: Skylines community. However, it should be noted that separation of functions is a notion very fundamental to the modernist (1930s–) school of urban planning, and this originated from the entirely reasonable desire to genuinely improve the human condition in cities by separating residential areas from a polluting industry. Because single-use zoning, together with the ideal of a single-family house for everyone and the use of personal automobiles for transport, turned out to be unsustainable in more ways than one, and because polluting industry is now relegated to a Someone Else’s Problem, mixed use has become (or is becoming) fashionable again, with current ideals and best practices in planning clearly diverging from those of the modernist era. Another unrealistic idea is, of course, that of a city designed from the ground up, which, although there are indeed real-world examples of fully planned cities, they are very rare. Many players do prefer to start with a tabula rasa in these types of games, and it’s of course much less work for the developers to create maps devoid of existing human population. I, for one, would love to see more maps where the starting point is an existing town, or a group of disjoint villages scattered on the map! Nb. the notion of planning as a profession emerged in the West mostly during the 19th century, before which cities had, for the most part, grown more or less organically. The need for central planning was in many cases precipitated by fires which could easily destroy neighborhoods or entire towns. Building fire-resistant cities in the era of predominantly wooden buildings necessitated measures such as firewalls between adjacent buildings, streets wider than the alleys of old, and separating neighborhoods with wide, tree-lined esplanades or boulevards. Conveniently, the destruction left by fires also provided the opportunity to realize these measures when rebuilding.

wartron 4y ago

Sounds like art imitating life.

CalRobert 4y ago

Ultimately it was a game more than sim. Note the lack of parking lots.

BinaryRage 4y ago

Same for SimCity 2013, except the flaws extended to every agent. I've always thought that's why they limited the city size so heavily. Such a shame, because there was so much promise there. Power, water, etc. randomly chose a direction at a junction, so even basic grid would make it impossible to power a building on the other side of the city, even if the power demand was there https://www.youtube.com/watch?v=tvq6zAMJfOU https://www.youtube.com/watch?v=tvq6zAMJfOU. Traffic and pedestrians were attracted to available houses/work, but randomly every day, rather than having a defined home/work location. I built a pedestrian heavy city and would watch crowds of pedestrians head for the nearest available house on a street, before the whole street filled, and they turned around for the next nearest. Same for work, shopping, despite there being plenty available.

ptmcc 4y ago
SC 2013 was such a let down after so much hype, for so many reasons. As a lifelong Sim-anything fan it was crushing. Cities Skylines seems like the successor to SimCity, but even that has some deep-rooted flaws in traffic management and agent flow. Some mods exist to help coax it a bit, but it's still just a broken approach at scale. Traffic and routing is hard, I get that, but there has to be a better way. Building a city around the routing flaws is not that much fun.
- standardUser 4y ago
  Cities Skylines can provide among the best city sim experiences to be had if you're willing to invest a day (or two) modding it to within inches of its life. That and 32gb of RAM
  - mrguyorama 4y ago
    Is there a list somewhere of "Essential" mods?
    - lp0_on_fire 4y ago
      The CitiesSkylines subreddit has a list that contains (IMO) a good number of useful and essential mods. Word of warning: if you're one of those people that likes to install a lot of mods keeping everything up to date and non-conflicting can be an pain the rear. There is, of course, a mod to keep track of which mods are out of date or could cause issues, but that's really a band-aid on top of a larger problem. The game is old enough now that many popular mod authors have long been abandoned their projects or otherwise moved on so you end up with things like "MyPopular Mod" and "MyPopular Mod UPTODATE" or "MyPopular Mod FORKED" or "Use this instead of MyPopular Mod". If I take a few weeks / months between plays this usually ends up with me having to take 30 minutes to an hour to get the mods up to date and tested. Not a huge amount of time, but when your gaming time is limited it's something to take into account.

matzf 4y ago

So these ant-like cars were supposed to be more than just decoration?

b0afc375b5 4y ago

Are there any SimCity-like games you would recommend? Or any comments on Cities: Skylines perhaps?

albertzeyer 4y ago
In Cities Skylines, each agent, each car actually does perform path planning. You can inspect the planned path of each car, and also follow it.
- onli 4y ago
  Skylines (which I liked) still has weird simulation errors. Like how many ships arrive at ports, which is an ever-changing amount and has no or little relation to the real transport demand. And the amount of trains using a train line depends on the number of stations, meaning outgoing train lines always need to be connected to a single one to not overflow. How single agents path is also weird, like how much they walk. I think I remember that homes were also not persistent? When separating city blocks completely fires would not get extinguished. Either the fire station assigned is random, or only a few actually can send cars out. Which breaks down in a city not fully connected by streets. Haven't played for a few years now (last run was with the industries dlc), but also haven't read about patches adressing such issues.
  - brailsafe 4y ago
    I ultimately gave up on skylines because I kind of broke my city and it got really tiresome to try and repair or start over. Tried a few mods to greater or lesser success but they just revealed other flaws. For example, whichever mod allowed for more realistic population densities; you'd have 700 families in a residential building or w/e, but no clue where they work, and likewise in the reverse. I somehow can't click on an office tower and see what the geographic distribution of occupants is, only those that are currently commuting. I'd also get strange issues like some of my subway lines inexplicably being totally vacant no matter what I did. It's also an incredibly inefficient game to run.

epups 4y ago

Can you explain this a little bit more? Are you saying that the game actually simulates each vehicle trip individually, and then decides on a random path at every intersection?

hypertele-Xii 4y ago
RollerCoaster Tycoon does the same, guests wander aimlessly around park and interact with whatever they come across while considering their needs. The Sims displays the other end of this spectrum, where agents path deliberately (while still considering their needs), and the difference in simulation scale is immense. Simple fact is, pathfinding is a performance bottleneck that hasn't been solved yet. We are still using algorithms from the 1960s, and no hardware acceleration exists. SimCity has always been more of a spreadsheet with houses on top.
- eru 4y ago
  You can do a lot of shortcuts with the pathing, because you are doing a lot of pathing on a graph that doesn't change much from frame-to-frame.
  - chongli 4y ago
    Exactly. The only time you should be calculating paths is after the player places new roads. Repeatedly calculating paths on a fixed graph is a huge waste of time!
    - db48x 4y ago
      It’s even easier than that since each agent only needs to plans a path once, when they start their trip. After that they are simply following a cached path, removing road segments from it as they go. Most games will simply not recalculate those paths when you change the network, because it causes a lag spike every time the player makes a change, and because most routes wouldn’t end up changing. Better to just have cars ignore roads that didn’t exist when they departed, and have them vanish if they need to take a road that has since been deleted.

dncornholio 4y ago

Does the city really get influenced by what junction a car or person would take? Weren't these objects just for visuals?

casenmgreen 4y ago
In SC2K, you do not see cars or people. I do not know if in the later versions, there is a correlation between visually depicted cars/people and trips (or if trips are used at all, although from what people are writing here, it seems they are).
- smcl 4y ago
  You do see a representation of the traffic, but yeah definitely not individual vehicles

tetha 4y ago

Interesting. This is similar to a common optimization in the genre of city builders with walkers, like Caesar or Pharaoh. In these games, buildings like a market or a temple spawn walkers, which walk on roads and distribute services and goods to tents and houses they walk past. An important optimization in these games is to avoid crossroads and junctions, because walkers tend to randomly choose a direction at junctions. This would make it a coin flip which of the two roads would get food or religious services, possibly causing all kinds of chaos. One of the best layouts as far as I recall was just a big block with a circular road going around it, because this forced the walkers to walk past all buildings in the block reliably.

casenmgreen 4y ago
Exactly. This is what you end up having to do in SC2K. You must direct the traffic, by not offering junctions.
lelandfe 4y ago
Heads up that the Pharaoh remake released today: https://store.steampowered.com/app/1351080/Pharaoh_A_New_Era/ https://store.steampowered.com/app/1351080/Pharaoh_A_New_Era...
- neura 4y ago
  Saw this. Really looking forward to checking it out for the very topics being discussed here. I love looking at how different teams implement these details. Is it just faked enough to be visually pleasing or do they really have each visual actor in the world doing the real work. :D Used to love playing with these details in the old version of Pharoah and Caesar.

saberience 4y ago

Are you arguing that a game in 1993 is flawed because it failed to accurately simulate a city populated with 100k+ people and associated cars and infrastructure? I think if you assumed such a thing in the first place your premise and assumptions were massively flawed. You're saying the game isn't playable because it was too different to real life? Did you notice the Superhero who arrives to fight natural disasters or the giant aliens who can invade? Or the fact that you can magically position fire "trucks" where you want instantly?

taink 4y ago
The flaw isn't that it is not realistic enough, but that it goes too much against an average human's preconception of how a basic traffic system should work. It is absolutely not unreasonable to expect a 1993 game to not choose a random route at a junction; it should use a basic pathfinding algorithm (which were well-known, even in 1993) to choose the closest one. Of course it is limited by performance but optimization is hardly a good counter-point to intuition in this kind of game.
- phkahler 4y ago
  What if the flawed routing simply exaggerates flaws with the way we think it should be designed? The number one bottleneck in real traffic is intersections. Some people think optimal city design should mix zoning types at a finer level. To your point though, we can't really demonstrate what's better when the agents are acting stupidly. I'd like to be able to learn what would work in the real world too.
  - BlueTemplar 4y ago
    Yeah, also it is not clear to me why is that so bad, so what that you have a circle line, wouldn't only a microscopic fraction of paths get stuck on it after a large number of crossroad steps ?
- mrguyorama 4y ago
  This game was meant to run on a 25mhz 386 and 4mb of RAM. Complex pathfinding and over-complicated sub-simulations would have drastically limited how large of a city you could build before your system just stopped working.

treeman79 4y ago

https://youtu.be/NTJQTc-TqpU https://youtu.be/NTJQTc-TqpU Someone that spent years building an optimized city. Six million residences.

mysterydip 4y ago

At least in the original simcity, as a path was made it was pushed to a stack. If the route didn't reach a destination, the stack was popped and intersections tried again. At least that's what I get from these https://lively-web.org/users/Dan/uploads/SimCityReverseDiagrams-1.pdf https://lively-web.org/users/Dan/uploads/SimCityReverseDiagr... Was this changed in 2k?

bombcar 4y ago
The original SimCity has (IIRC) checks to see if services were available and ways to estimate traffic load, later ones tried to simulate actual trips. So it went from “can this house reach a job” to “simulate this house driving to work” - the difference comes from a high density doing one check to doing multiple.

deleted 4y ago

[deleted]