We built the city of Colombo in Cities:Skylines | Hacker News Reader

We built the city of Colombo in Cities:Skylines

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511 pointsicaruswept183 comments

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Modified traffic behavior using TM:PE mod to reflect Sri Lankan driving habits:

- Buses may ignore lane arrows

- Vehicles may enter blocked junctions

- Vehicles may do U-turns at junctions

- 10% of drivers are reckless

- Vehicles may park on the sides of streets

- Three wheelers and scooters

Brilliant!

Haha, thanks!

Do you happen to observe same traffic jams in same area and time windows as in the real world?

Also, do City Skyline drivers behaving like drivers who would use Waze (or could be configured so that a certain amount do) ?

We see broadly the same chokepoints (Galle Road, Baseline Road, the arteries feeding into Colombo). Modify these and the chokepoints distribute themselves. Small chokepoints don't always appear.

Broadly, if you can do it by fiddling with this: https://doc.tmpe.me/vehicles.html, you can pull it off.

my god. this makes cities skylines way more accurate with regard to south asian cities. still needs random elephants loaded up on trucks.

And cows that have the right-of-way.

https://docs.legis.wisconsin.gov/statutes/statutes/346/iii/2...

I am sure you can find similar laws in other states.

Yeah but cows rarely roam free there :)

Cows don't roam free in Sri Lankan cities, either. You are aware that South Asia is a subcontinent and a whole set of islands, and not one singular city,right?

I have heard many Hindus consider the cow a holy animal and let them roam where they please. And there are many Hindus in Sri Lanka (though there are more buddhists who don't consider cows holy but are vegetarians).

And yes I know the region pretty well. I've lived more than half my life outside my home country (in 3 different ones). Though never been to Sri Lanka no.

Never seen a single cow on the road in Sri Lanka. Though I only visited the western half of the country from about the Colombo to Kandy line down to the very southernmost tip.

However, the other settings seem about right to conservative vs. reality. I literally just got out of the airport in a taxi and thought I was gonna die, so fast and close to an oncoming car was the taxi going. Probably about two atoms worth of "air" between their side mirror and the taxi's.

Traffic lights might as well not exist. Everyone was just going through the intersection at the same time. No elephants on the raods either but an army of Tuk Tuks. Actually preferable to car taxis. Never took one again. Bus travel was interesting as well.

Most Buddhists are not vegetarians. There's a huge gap between Wikipedia stats and real life, as it is the case everywhere.

Using "Knowing the region pretty well" to be confident about a country you've never set foot in is like me assuming alligators are roaming free in corn fields in Iowa because I've been to a few states in US and have seen Florida through youtube.

I am a Buddhist from Sri Lanka. Where on earth are you getting this stuff about us being vegetarians?

You clearly don't know the region half as well as you think you do.

All the Buddhists I've met told me that they're vegetarians because they believe animals also have souls and they could be reincarnated as one.

But they were mostly Tibetan or Thai Buddhists. Most of my experience is indeed from Thailand and India.

Ah yes, so all Sri Lankan buddhists must be vegetarian.

Mate, <50% of India is vegetarian.

Digging through my photos... it was the '08 Great Road Trip... and I even took it on my iPhone then which means that I've got all the other metadata info.

October 3rd, 2008 at 1:42 pm. The geocoding location on it puts it at https://www.google.com/maps/@48.3855579,-114.0865119,3a,75y,... though I'm not 100% sure that is the exact location. The photo is https://imgur.com/a/rzwSjak

I’ve always found amusing that it is illegal to race or furiously ride a horse or other animal on a highway in Ontario.

I’m angry, can’t ride my emu down the 401.

https://canlii.ca/t/2fq#sec173

Alot of laws in the Anglosphere use really ancient wording for things.

I think if you throw something at people in certain states (Florida comes to mind) it's considered "launching a missile" at them

I've attempted something similar for a city of 20,000 before using an overlay mod but map projection issues between the DEM and images along with city simulation scaling just yielded a stretched blob with 95% industrial traffic and a queue entering the city that never ended. I will check their tuning parameters and see how they handled it. It was fun to build regardless.

I've been waiting to try with CS:2 using aerial photo and lidar data of Vancouver that I've collected myself. Mod support is still weak compared to CS:1 but I'm hopeful that it's possible. I'd like to release a DEM, DEM+roads, and then the fully built version as three separate maps.

Can you explain the projection issues you faced with the DEM? I thought something like gdal can reproject any data into a standard projection like web Mercator.

If I recall correctly Cities Skylines needs a UTM-like projection but I think I made an error with the input data and got the X/Y scaling wrong. It was a fairly amateurish attempt and my knowledge of coordinate reference systems has improved quite a bit since then so I hope to fix that for the next attempt.

Good news is you can even overlay screenshots of Google Earth (which uses high-res data, some of it at 30 cm2 per pixel). Will take some fiddling with the coords, but it works!

Sadly, that happens. We use image overlay and exports off ESPG 4326 and tweaked the hell out of the coords until it worked. Even then there are still issues - which is why we're about 100m shorter than the real city. The overlays match perfectly, but in reality distances are always a few meters off across a large stretch. OSM imports broke completely, so I just ended up doing all the roads by hand with the maps on a second monitor.

There's always a point where you look at the automated solution and think "Okay but... how long would it take to just to do manually?"

I enjoyed your comprehensive write-up. I really like how you didn't get too lost in the details when the technical limitations cropped up and kept the focus on the interactivity and public awareness. Very fun project :)

Thanks!

C:S 1 has quite a few "thundering herd" issues, like perfectly cyclic deathwaves. This includes extreme industrial traffic if you zone it all in at once. The capacity of (all) buildings is also pretty extreme. Adding Realistic Population 2 and Lifecycle Rebalance Revisited brings it down to less gamey and more towards realistic, and you can tweak from there.

I should look into these mods, the death waves were annoying. I mean I get it, you build a big new residential area, people move in quickly and are all roughly the same age when they do, but they could've done something to fix it like randomize ages or have people move out of the city and replaced by a differently aged person.

Maybe this might help: the list of mods and what they do. You can pick what seems most useful for your game.

https://github.com/team-watchdog/colombo-skylines/wiki/mod-c...

Yup, we’ve got a big list of mods to help alleviate some of these issues. Due to the way we’ve modeled the corridors and daily population flow in and out of the city, we still get roving herds of ambulances…

I recently started a company called Good Places, actually Gode Steder in Norwegian, where we simply design good places. Our goal is to design city districts with better quality of live and status than urban sprawl. You can't force people to live in cities, but you can make urban districts that are for better suited for families than urban sprawl with single family homes. The aesthetic qualities is just as important as the quality of the rest of the city planning. If that means making buildings inspired by 150 years old buildings, then so be it.

That sounds great. How would one go about this with a city like Mumbai?

Have you heard of eMOTIONAL Cities by any chance? https://emotionalcities-h2020.eu/

It's basically an ongoing large-scale research project working to quantify the way people experience city spaces from a neuroscience perspective (or at least that's my understanding -- I work with some of the people who are working on it.) Maybe the work they're doing could be relevant to what you all are doing?

This is what peak Good Place with best quality of living looks like: https://www.shutterstock.com/shutterstock/photos/136787633/d...

It also isn't part of urban sprawl.

Do you have a link?

Wow this must have taken quite awhile. I've always wanted to do something similar with my hometown (for the giggles) and now I have a guide on how to start.

Have urban planners been receptive to using this model for how they work on issues that affect the city?

is there any work done to show that Cities Skyline can approximate real problems and is not just a fancy game?

I'm asking based off of what they wrote in the readme

"While not a completely accurate simulation, this "toy universe model" provides a useful tool for visualizing and communicating urban development concepts. We present this tool in the hope that it will facilitate better communication and understanding of urban planning issues in Colombo."

Not completely accurate sounds like a bold claim of accuracy imo

Does the following description of it as a "toy universe model" affect how you judge the claims of accuracy?

That is a separate claim

Only if you're absurdly literalist. In British English that would be immediately understood as "not very accurate at all".

… really? I’m not sure I believe that.

“Not completely” seems to clearly indicate that it is not 100% accurate which seems worth clarifying only if the base assumption is that it’s very good.

Really. Especially taken with the "toy" statement that follows, this reads to me like "this isn't perfect but we had a good crack at it and are happy with how good it came out for our purposes".

I’m sorry but I fail to see how this quote you’ve provided isn’t suggesting that the model is good. Your message is clearly positive.

What I’m saying is that this is almost certainly completely untested and entirely reliant on the fun game mechanics used to simplify the experience of playing Cities: Skylines. Like, iirc, the game does not implement any sort of rush hour logic.

Even if it is "just a fancy game", things like this can be very educational for upcoming generations of real city planner types. Get kids interested in those "real problems" in healthy ways early in life, and give them tools / toys to explore their ideas with. :)

the question is, are the precepts baked into the equations around traffic flow, urban design, etc, truly a reflection of reality. In SC3K, my low density residential housing was never as happy as high density, is that based on reality? My enactment of endless (in sc3k, check all boxes) series of ordinances produced the best result. Was the neighborhood around the casino really crime ridden or was that a trope?

Are the models based on real life or are we using a game to pretend real life - like making a game about the wonders of say, collectivization, rather than maybe creating a simulator for how market trade reaallly works.

Methodology here: https://github.com/team-watchdog/colombo-skylines/wiki/Intro...

We've also tweaked many of the assumptions (traffic flow, citizen lifecycles etc) https://github.com/team-watchdog/colombo-skylines/wiki/mod-c... to get "somewhere in the vicinity" of how people actually behave - nursery school at 6 years old, high school after, then a job, maybe college, then employment and retirement at 65.

In some of the work that I was involved in years back we were using CDR (call detail records) to estimate human mobility. See: https://medium.com/@yudhanjaya/how-people-come-to-nallur-7d3...

We're certainly not that accurate, as the broader you go with simulation, the less deep you can get to. But as a teaching tool to help people think about the instersection of complex systems, it's decent.

If I had more time I'd spent it making a new asset pack so those houses look more Sri Lankan.

I wouldn't make any serious policy decisions based on City Skylines, it's a resource management game not a serious simulation if that's what you're asking.

In the case of Australia (my home), the casino itself is crime ridden (mainly the corporation behind the casino, and its behind-closed-doors relationships with organised crime and with government - but money laundering and other crimes also occur on the casino floor), while the neighbourhood around the casino is quite safe, peaceful, and upmarket.

What's the standard of proof for a commercially available package other than "these are the municipalities/planning authorities that have used this before?"

Typically you look for its use in both academia and in the field (hence CUBE, for instance; widely used by the academics at Moratuwa who then go on to work on actual projects)

Cities Skylines in the vanilla mode (and most, if not all, city builder games before it) famously ignores problems of car storage. It may actually seem like cars are somewhat sustainable.

Is there a mod out there that adds car storage? I can imagine the cities look less idealised when half the space is taken up by car parking lots lol.

TM:PE (Traffic Manager: President Edition) has a setting for more realistic parking: https://doc.tmpe.me/gameplay.html#parking-ai

I don't know if it strictly mandates having physical space persistently for every car that exists in the city, or whether cars still somehow spawn and despawn dynamically under some circumstances.

Edit: Looks like the car despawns if an attempt to find a parking space close enough to destination fails ten times.

They've been surprisingly receptive. We've taken care to point out that the map is not the territory, but we've had conversations with urban planners and professors (especially the Town and Country planning department at the University of Moratuwa): they're very interested in using this as a teaching tool for students. I recently did a presentation to 150 students + urban designers and transport specialists, and they were super interested in a) trying this on smaller pieces at greater fidelity b) simulating other cities as well (like Kandy) and smaller towns where there is more planning leeway c) using this to illustrate effects of plans like COMTRANS (https://www.transport.gov.lk/web/images/downloads/F-CoMTrans...) which is why we built the thing in the first place.

I love to hear the reception went so well. Awesome to see this game used as a tool.

> So we have a few notable issues: 3.Perfect adherence to schedules in public transport, unlike real-world variation

I love this quote from readme.md

Same, although I am surprised because busses in cities skylines are usually still affected by car traffic issues. Trains would run perfectly though.

So because the number of active vehicles is much lower than reality, the road network is actually a lot more efficient: it’s a nearly 1:1 scale city with less than a fifth of the real vehicles that would take up the streets. Mostly because of this, public transport in game is a lot better than our particular reality. In fact, the trains are completely underutilized - we can tweak transport modal share (and should) to get the numbers to balance better.

I suspect it's missing the traffic coming into the city from outside

No, that’s modeled in. Those lanes are always active.

I remember doing this in SimCity 4 a few years ago for a real small town of ~7000 and it actually worked remarkably well out of the box. Residential/Commercial/Industrial came out fairly balanced. The only thing I had to mod to make it really work were the catchment areas for schools etc, which are very small by default. I found a mod that made them 2-3 times bigger radius (but actual capacity stayed the same, and worked well enough).

There's something especially fun and interesting about replicating real places you know in games. That's something I don't think the people who freaked out about kids making their house or school in Doom or Quake ever really understood.

For sure. I used to try making the layouts of our old cities (Anuradhapura etc) in games like Pharaoh and Ceasar 3.

If you’re into doom modding - have you seen myhouse.wad? Worth looking up on YouTube. Phenomenal achievement imo

> That's something I don't think the people who freaked out about kids making their house or school in Doom or Quake ever really understood.

We made maps of our school(s) to play in Counter Strike, I understand people freak out if they don't really understand what video games are. Especially when it was around the time when people were starting to freak out about if video games make people violent or not, because some school shooters in the US had some violent games they presumable played before their attack.

I always found the argument that shooters played violent video games extremely weak. Of course they play video games, like most people their age.

Same - I wanted to recreate my school for Counterstrike because I knew the building so well and if I played it with schoolmates we'd all know it like the back of our hands and associate different areas with different memories etc. leading to a more unique (and probably funny) experience. It had nothing to do with violence in reality.

Unreal Tournament level editor was the easiest for a noob like me. We created our dorm rooms, campuses, our houses back home. That being said, this was 25 years ago (in the US), not before school shootings but certainly not like they are today.

Video games and guns themselves being the cause of shootings are just typical unhealthy excuse making in order to avoid having to actually address the real issues that would require consequences or accountability for and by people who very much do not want any consequences or accountability to affect them in any way, whether that is individuals or groups.

I recall making a map of my high school in Duke Nukem 3D well before Columbine. I think the only reason was it was the closest floorplan I had readily available at the time and I had no Internet access. I was more interested in playing with the Build engine/map editor than actually shooting things.

A crude 'digital twin` with detailed land use and zoning based on official city development plans and data centered around 2020; over a million virtual citizens, simulating population dynamics that reflect large-scale, real-world demographics and human movement; public transport based on actual route data.

I visited Sri Lanka a few years ago, and mostly loved it (there were some annoying bits, of course, but definitely one of the best trips I've had).

Since then, Colombo is one of my favourite cities as a reference. It has such weird urban planning (or lack thereof), I often find myself comparing other cities to it. It would be awesome to be able to revisit it, and recheck my reference points, virtually in a game.

Glad you enjoyed it. "Lack of planning" is indeed the best way to describe Colombo.

I don’t think we should be encouraging tourism to an apartheid state like SL

Every country is an apartheid country if you try hard enough

[flagged]

Consistency is key

This actually sounds like a great idea, I've often wondered with some of the advanced city simulators like this if this might be possible. Seems like a good use of AI if it had access to all those data sets local government GIS folks use (hopefully) to align this sort of data to make these virtual representations.

Problem I think would be most folks that might even do this as a hobby probably don't have that access to GIS and other data (cheaply) like they did here, and government workers are government workers, so nothing interesting will usually ever happen there. Certainly not in the US with any government entity I've worked with here at least

Oddly enough, this is how our own universe simulation got started

Realistically I don't think the UDA (Urban Development Authority) will use this, BUT we have had calls with them where they asked to see a demo and seemed massively excited at the prospect of being able to visualize changes in the character of the city (in fact they wanted to know if we could build municipal buildings if they gave us the maps). University students who eventually become GIS folks seem more like the audience that will actually end up running and tweaking this.

I had a similar notion, as I prior worked with a large southern California municipality that was into "smart city" things as a solutions architect, and they would have loved for something like this for the same reasons you stated, particularly visual changes or features, adjusting pedestrian/bike/car traffic flows, points of interest, etc.

I would love to know how large of a city would be possible to "import" and run with enough of a like data set. I would imagine it would give any GIS nerd a boner if they could do so themselves.

Even remotely close I would consider a feat, so bravo to the team that did this!

Thanks! You may want to read the methodology - most of the imports broke and it ended up being a lot of manual work: https://github.com/team-watchdog/colombo-skylines/wiki/Intro...

As for limits, when modded to the hilt, Skylines will give you:

298.6 sq km maximum area

1,048,576 maximum citizens

49,152 maximum individual buildings

65,636 maximum vehicles in motion

65,636 maximum parked vehicles

256 maximum transport lines (bus routes, train routes)

That will no doubt change the nature of the city you can set up - you could do a large city very sparsely, or a smaller area in greater detail.

Is the limit for vehicles really 65636, or is this just a typo for 65536?

That's what immediately caught my eye, too.

It's a typo. Also, you need a mod to even reach that figure, by default the limits are substantially lower (16384 for moving vehicles, 2x that for parked vehicles).

Thanks for the spot, will double check. Yeah, we’re modded to the hilt here. This is taking the game as far as the engine can handle.

> The project is conducted in partnership with the Strengthening Social Cohesion and Peace in Sri Lanka (SCOPE) programme, co-funded by the European Union and German Federal Foreign Office. SCOPE is implemented by GIZ in partnership with the Ministry of Justice, Prisons Affairs and Constitutional Reforms.

Is this specific project really funded by tax-payers money?

> Curated thousands of 3D assets to replace default buildings

How does this help to achieve any of these below ?

> Potential applications include:

> Simulating changes in roads, transport routes

> Exploring effects of changes in private transport policies

> Visualizing impact of new infrastructure like monorails or wider pavements

> Assessing effects of introducing more green spaces or parking areas

I thought it was a pretty cool project, thought it was self-funded. But I agree I have no idea why I should finance this with my European taxpayer money.

I'd rather they spend it on projects like these, where at least some people get joy playing videogames for work. Alternative is they get together and cook up some of the worst bureaucratic dogshit wrapped in catshit they call quality legislation.

wait until you see the Horizon Europe project

> Horizon Europe

For people who are unaware, Horizon Europe is a research initiative that spans a wide range of interests, from nuclear energy to basically anything else, with the fine restriction that all research has to be open and public.

https://research-and-innovation.ec.europa.eu/funding/funding...

I'm not sure what the "dunk" is supposed to mean here, are you saying funding research like this is a waste of taxpayers money?

Agreed!

I really enjoy seeing stuff like Horizon. There are so many bad examples for taxpayers money (e.g. Gaia-X), but Horizon ain't that.

People who dunk on public projects usually are unaware of all the research their own government finances

Or, it's possible, they are aware and don't support it. I don't think "My government is better then yours" was the goal here...

The same people might also dunk on public projects funded by their own governments.

But I think they may not be quite aware of:

1. How many present-day things we take for granted have been enabled by basic research, sometimes on weird or unimportant-sounding topics.

2. How basic research can't necessarily quite go only for "important" and big results and skip the "unimportant" results and topics, or know in advance which ones are going to be useful and which ones aren't.

3. How investments in fundamental research are, proportionally speaking, actually quite small. The 100 billion euros for Horizon Europe sounds like a lot, but that spans over seven years (2021 to 2027), and if it's funding a crapton of all kinds of research, there are also almost certainly going to be lots of results that are going to be useful. And, granted, also lots of ones that won't be, at least not directly. But even the vast majority of the useful ones are going to fly under the radar for just about everyone outside of the particular field so it's easy to not be aware of them (see also points 1 and 2).

The EU has a population of ~450 million. The 100B euros over 7 years means the costs are ~225 euros per EU resident in total, or ~32 euros per year. I'm almost certainly paying more than the average EU resident, so let's say I'm paying 70 euros per year for the whole deal.

I don't really have a huge problem with that. If it were for some kind of a small or narrow range of projects, I might. But it's not.

There is, of course, the possibility that he was being sarcastic.

Yeah, I suppose, but "EU throws tax payer money in the sea" and "EU stifles innovation with regulation" are so common sentiments around these parts that I'm unsure if it's sarcasm or not, 50/50 at this point.

I wasn't.

With the prevalence of uniformed opinions about the EU and how it works on HN, that is a long shot (or big reach as the kids say).

I think projects this magnitude are not good, with a 100B euro pricetag that will be diluted into paying for bureaucracy and conferences. It's good that it's keeping people busy though, can't criticise that.

Just so others get a sense of the scale involved here:

Currently the portal (CORDIS) has 13674 projects listed as part of Horizon Europe[0]. 100B eur would on average be ~73K EUR per project.

While Horizon Europe itself is a huge project, the projects funded from it isn't always huge projects but sometimes small, incremental steps towards something, and sometimes larger projects.

But with a perspective on how many projects are within the framework, 100B doesn't sound so much anymore.

- [0] https://cordis.europa.eu/search?q=contenttype%3D%27project%2...

You think 100B doesn't sound much? Do you want to up the numbers to 200B instead? I mean after all it's Cancer research

> You think 100B doesn't sound much?

I think "~73K EUR per project" doesn't sound much, and I'd happily pay more taxes if I could be sure research would receive more of my taxes.

I mean look at this project, https://cordis.europa.eu/project/id/101183057 "A digital twin of human milk". Sounds like a homerun right? I'd say 80% of the projects are just filled with buzzwords to get funding, and they rarely produce any good outcomes

> rarely produce any good outcomes

That's the nature of research.

> The research and innovation program, named GALATEA, stands as a pioneering venture targeting infant nutrition through the development of a digital twin of human milk.

> The overarching objective is to create a sophisticated simulation platform that mirrors the intricate composition of human milk, allowing for the formulation of personalized nutrition plans for infants, particularly those born prematurely.

> Anticipated outcomes include enhanced health outcomes for newborns, a deeper understanding of human milk for the advancement of artificial milk formulations, and the establishment of a robust research community dedicated to neonatal nutrition.

I mean, the ideal outcomes sound pretty good. And the non-ideal outcome is we learnt about a bunch of stuff that doesn't work, that's how research works after all.

What, exactly, is your critique about that particular research? That they call it a "digital twin", or what?

I don't see any buzzwords there; simulation is an indispensable tool modern for biochemistry.

If you stopped reading at the (admittedly daft) acronym, it's worth keeping in mind that, outside computer circles, 'digital twin' now refers to any kind of simulation or tracking of a physical resource. This is not some nebulous proposal for a blockchain NFT of human milk, it's genuine scientific research.

It's not a monolithic project, it's a funding pool where an organisation can apply for access. It's not even limited to EU member states, the UK has returned as a partner after the Conservative party got their panties in a twist about it during Brexit.

And latest news is that Canada also joined up :)

> Canada is joining the growing group of non-EU countries who have associated to the EU's research and innovation programme, Horizon Europe, and will work jointly on large-scale projects tackling our biggest challenges.

https://ec.europa.eu/commission/presscorner/detail/en/IP_24_...

The more the merrier!

In the US we spend 10x that on military expenditures that have marginal benefit to our own society.

I think the EU model is preferable.

Horizon Europe funds many of the research projects my organisation works on, such as cancer research, COVID-19 and general microbiology research...

Do you mind sharing this?

The EU is the world's main source of and main destination for foreign direct investment (FDI). Inward and outward FDI play a fundamental role for generating sustainable economic growth, business opportunities, employment, technological development and innovation.

Seems worth it as a teaching method.

Playing Devil's Advocate, making the game look more like the real world (I am assuming this is what was meant by "curating 3D assets") would help tremendously in "simulating", "exploring", "visualizing", and "assessing" the impacts and effects of changes and new additions to city policies and infrastructure to the average man.

As for whether this is a good use of taxpayer money... well, it could be worse.

Yup. The 3D assets are from Steam workshop and impact visuals and population calculations (since pop calc is based on square footage). Otherwise, with Skylines' defaults, this would all look like the Netherlands.

They're funding us to do this and a few other things:

2) Create and publish maps of Sri Lanka, especially for journalists to use for environment and land use reporting, for 2017-2024, using Sentinel-2 data

3) Build and publish our wiki of 70+ crops that can be grown in Sri Lankan backyards

4) Build and publish our open-source DIY agricultural sensor kit

5) Design and publish our journalism and media literacy course for young journalists and the general public

In general, these folks (https://www.giz.de) are one of main european branches of NGO funding in the Global South. This is a very small project in their overall scheme of things - your tax money goes to a lot of places in the world.

It only seems fair to also include the previous block:

Ultimately, what we realized was that there had to be some visual way to bridge the gap between professional expertise (often confined to academic papers and reports) and public understanding.

Our virtual city of Colombo serves as a crude "Digital Twin," offering a platform to:

1. Visualize and understand current urban design issues

2. Test and communicate potential infrastructure changes

3. Explore the impact of policy decisions on traffic and population distribution

4. Educate students and the public about urban planning concepts

Note how it specifically mentions public understanding and education twice. If you want the public to be able to relate to such a simulation, you want it to look as close as possible to the real thing. Otherwise, it will just remain an abstract simulation in which people will have trouble recognizing their own city.

> Notable issues:

> Perfect adherence to schedules in public transport, unlike real-world variation

"Cost-effectiveness: $19.99 for a perpetual license vs. $6,000-$8,600 for professional software like CUBE"

I hope their efforts have carry over to other localities wanting to do something like this. They're a good example for others.

I was hoping there'd be some report on what they'd learned about the city as a result of modeling it and, presumably, testing some changes. But don't get me wrong, this is awesome anyway.

Coming up. I'm implementing some small bits of the COMTRANs plan, as it's politically relevant to our election cycle right now (https://www.transport.gov.lk/web/images/downloads/F-CoMTrans...). It won't be a full implementation - we're a small team, and I want to encourage other people to come on board with their ideas. We do have a reasonable "how we did this" section if you're interested! https://github.com/team-watchdog/colombo-skylines/wiki/Intro...

Many, many years ago (2004?) I was on a NSF research project about participatory GIS, trying to help people (voters) make informed choices about transportation alternatives in a region—which road or rail improvements to make, and how to apportion funds between them. At the time, we dreamed about being able to let people run a simulation of the consequences of their chosen package, but that was definitely not feasible with the technology we had at the time. That's the background for why I'm so envious of what y'all pulled off!

That’s very cool! Do you have any papers I can read?

We had a similar experience with the university labs: this professor of transport telling us how he was working on letting people modify land use maps to their liking in the 90s and early 2000s, and wishing they had tools like this.

Hopefully we too will soon see stuff that makes us think “damn, I’m so envious!”

Awesome effort, always wanted to see our colombo on a game! It's really extensive and seems to be made towards public policy, Thanks Yudanjaya and Nimesha!

Cheers!

This looks super cool! Amazing project! I am really curious to try this idea at a smaller city. How much type and how many people took this endeavor?

You can download a height map file from https://terrain.party/ or https://heightmap.skydark.pl/ and start a new game with the unlimited money cheat. Then it's just a matter of placing roads, utilities, public services and zoning the rest (that's the fun part).

Sadly, the height maps and the OSM road imports were quite borked, so I just ended up doing all the roads by hand with the maps on a second monitor. Some screenshots of the process here: https://github.com/team-watchdog/colombo-skylines/wiki/Intro...

So two people (myself and Nimesha) working for about four months straight, I think. Mostly eight to ten hour days. Three academics helping us find data for when public sources ran dry (especially flow along the corridors) - see the workflow at https://github.com/team-watchdog/colombo-skylines/wiki/Intro...

Am I the only one that can't find "Conclusion and Future Applications" section ? I'm really interested in their plans here

You’re right, we don’t have one up yet. We did a few implementations of various government plans over the years (the Japan-funded COMTRANS being the most prominent) and I’ve invited a professional urban designer who works with the government to examine applications and limitations- so a more professional eval than just us saying “here’s a thing!”

Might write it all up as a paper if we have time.

I was surprised that near Sri Lanka there is a large area of sea landfill. As I explored the Google Map I felt it has a "taste" of Chinese companies and so it is: https://en.wikipedia.org/wiki/Port_City_Colombo

Anyone have some screenshots? I'm not installing Cities Skylines just to view this. Sounds pretty awesome overall.

Did you try clicking the link?

Not sure if it’s still there but on twitter they had a system where you’d have to click through before you’re allowed to submit a comment.

HN needs this!

[Meta] so how do you report when the link is not working, or blocked for your geo?

I don’t think they check or can check if you actually loaded the page. So I think they check only that the link was clicked

> Not sure if it’s still there but on twitter they had a system where you’d have to click through before you’re allowed to submit a comment.

The system did not prevent you from replying, it just added a warning message and a little friction to doing so.

The readme files in the repo have screenshots. Tried linking them here, but the URLs are massive, so let me link the docs -

1) Methodology: https://github.com/team-watchdog/colombo-skylines/wiki/Intro...

2) Main readme: https://github.com/team-watchdog/colombo-skylines

I remember learning long time ago that the people who made cities skylines also made actual city simulation software. Or the game was a derivative of a simulation software. Something along those lines. There were screenshots of the tool. I can't find it anymore.

This is crazy! What if one day the citizens in the game can be mapped to real ones also?!

I'm reminded of Tom Stoppard's Arcadia, and the child genius Thomasina . . . "If you could stop every atom in its position and direction, and if your mind could comprehend all the actions thus suspended, then if you were really, really good at algebra . . ."

You would make Heisenberg roll in his grave!

Every tornado-generating butterfly would be out of a job, for sure

curious why colombo? cities skylines doesn't exactly have tuktuks as a transportation option (though it really should...)

Plus you don't need a city simulation to see that the city desperately needs a good metro.

> cities skylines doesn't exactly have tuktuks as a transportation option (though it really should...)

It does now; we've modded it to use tuk assets based on the RDA's modal share estimates (see screenshots)

Is using games for real-life city planning a viable option to later apply in real life? I.e. if my city wanted to try out a new metro line, is replicating the city in Cities: Skylines good enough to simulate what would happen?

Related (Kerbal Space Program): https://xkcd.com/1356/

Not really, conceptually it probably shares a lot of the same foundations that a useful simulator would have, but its important to keep in mind that they aren't actually simulators of cities in a realistic sense.

Games such as cities, inherently embed a view of how the "right" city would be organized, providing tools and incentives to nudge you in that direction. Consider how all social problems can be solved by simply plopping down the relevant class of building nearby. Or simply the absence of parking lots!

There's this old article on the subject: https://www.polygon.com/videos/2021/4/1/22352583/simcity-hid...

Depends on how much of the games underlying assumptions you can overwrite, and of course the fidelity you’re going for. In our case we’ve modified everything from citizen lifecycles to traffic behaviour to population calculations based on square footage - but this is still more in the realm of “visualization and communication” than “professional planning tool”.

For real life planning, many concept in Cities Skylines are also in professional software. e.g. in Autodesk Infraworks you can import roads, drag out a spline for a new metro line, then run a simulation to see the affect on traffic and other transport infrastructure.

Looks really interesting, but I'm not buying a license and setting it up just to have a look. Is there a video available ? Hindsights from the creator on possible real world application ?

Will make a YouTube video (and an eval from a professional urban designer is coming up).

Do city planners and leaders have comparable commercial simulations? If not, I’m always surprised why they don’t use games like City Skylines especially cities much smaller than Columbo.

They mention considering CUBE as an alternative.

Interesting! Very similar to this for Minecraft: https://geoboxers.com

This is exceptionally cool work. I’d love to see it running.

once upon a time, players would show their real-world cities in Simcity. Oh, how the mighty have fallen !

Turns out there was a lot of strategizing behind this overtake, and its an interesting read [1]

[1] https://www.polygon.com/features/2015/4/8/8340665/cities-sky...

SimCity 2013, a trainwreck of a game, switched to an agent-based simulation to compete with Cities Skylines. It ran horribly, inheriting all of CS’s performance issues and gaining none of SC4’s benefits. It also added network features (DRM) so EA can notify your Smart Fridge of your compensation copy of Need for Speed after they scammed you $60 for SC2013. Moving on.

Here's the real debate: SimCity 4 vs Cities: Skylines. SC4 uses a population-based statistical simulation. Cities: Skylines, stemming from Paradox's Cities In Motion (built with Unity engine [1]) focuses on traffic modeling using an agent-based simulation. CS excels at traffic flows because it’s designed for that purpose.

It's the micro-level accuracy of Cities: Skylines "agents" and SC4’s macro-level realism of its "Sims."

Instead of creating individual agents for traffic simulation, SC4 runs a pathfinding heuristic to find the fastest route between Sims' homes and jobs. Maxis designed this simulation to run on a 2004 Pentium III 500MHz with 128 MB RAM. Surprisingly, it still holds up today.

In CS, agents return to designated homes. In SC4, Sims returns to the nearest vacant home after work. SC4's simplified simulation reveals the optimal path for Sims. This difference might seem immersion-breaking, but perfect pathfinding uncovers the most efficient urban designs that might initially be hidden. Isn't that the whole point of the simulation?

SC4 isn’t perfect. Casual players ask: Why no diagonal roads? Why are my buses unused? Why aren't Sims going to work? The Network Addon Mod (NAM) [2], around 2004, has addressed some of these issues. It’s not perfect, but it makes the simulation smarter, so Sims can make decisions closer to agent-based solutions. NAM is the band aid covering the small cut that Cities Skylines makes in its otherwise superior simulation.

SimCity 4 still holds its own as a city simulator.

[1] https://web.archive.org/web/20220716021755/https://unity.com...

[2] https://www.sc4nam.com/docs/feature-guides/the-nam-traffic-s...

Did you manage to emulate the traffic jam in Nugegoda and Rajagiriya?

Good stuff by the way. Awesome to see this kind of thing happening.

At some point I would expect you to write your own simulation engine given the serious limitations you ran into

How bad those limitations are depends on the purpose of the simulation, they satisfy a few uses cases even with those limits. Also the skill sets involved in those two tasks are quite different.

I've had some maintenance issues with my car, guess I should just design and manufacture my own.

I think at some point I will, but this is a task that takes multiple overlapping fields of expertise - from simulations to 3D rendering. I'll teach myself over time. I build little procedural generation experiments for fun that make their way into my books. But this is one of those dreams that will take me a couple of years to get to the level where I'm competent enough to go for it.

Is it necessary to work in 3D initially? You can make the problem a lot easier when working in 2D.

Goal here was to build a visualization and communication tool; 3D is an essential component of that. For 2D, land use maps already exist.

And Running on an overclocked epyc processor with dual 4090s you get a whole FPS in it too!

Until Windows starts updating in background!

I wonder how long it would take an ai program to do this based on satélite imagery

Unexpected place to find stuff about my favorite game

Now you can grow it into Magnasanti (the 6 million inhabitants SimCity 3000 city)

Oddly enough I never played SimCity. Closest from those times for me were Ceasar III and Pharaoh (which I'm playing again now: there's a very good remake).

Is this the Magnasanti you speak of? https://www.moma.org/interactives/exhibitions/2013/designand...

It looks fascinating.

Yes, that's the one

Magnasanti is like _the_ SimCity map people who played know of. This video made it pretty famous. https://www.youtube.com/watch?v=NTJQTc-TqpU

Neat, now combine this with Project Sid for a full simulation... https://altera.al/

What is the actual point of this?

Now try building Venice, Italy. Ha!

> Key Limitations [...] > Perfect adherence to schedules in public transport, unlike real-world variation

LOL

Now I want to do this for my hometown.

Same!

You should!

> Our goal was to create a more accessible and visual tool for citizens to comprehend urban problems and judge the impact of different decisions.

Building atop an old closed source video game isn't as accessible as would be ideal.

What are some open source and open standard starting points for this (other than OpenStreetMap), and how close do they get you?

(I once built something atop Google Earth, which made sense at the time, but I would've loved to be able to do it atop Web browser features we have today, and open source.)

Not even remotely close. If you have millions of dollars and lots of talented programmers, I can build an engine from scratch. We do not live in an ideal world - public policy is about the art of the possible, and $19.99 (cost of Skylines in Sri Lanka) is a massive improvement from the $8000 a year fee for CUBE or OpenPaths. I do want to build a sim someday, but I estimate the learning of it will take me a few years to complete. Right now I'm at the stage of writing basic galaxy generator toys like https://github.com/yudhanjaya/GalaxyGen

This is super impressive! I'd agree the open-source tooling isn't there yet, but it's coming in a few places. I started a 3D street visualizer but it's only at the scope of a few blocks at a time, not as large as a city area although we'd like to get there someday: https://github.com/3dstreet/3dstreet/

There's also https://github.com/a-b-street/abstreet for larger area simulation but with less visual fidelity

Very cool, great to see progress in this!

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