In remembering that cities are not roads alone, but also streets, paths and tracks, there is a lot of potential for this approach to building all of them

> The word street is still sometimes used informally as a synonym for road, but city residents and urban planners draw a significant modern distinction: a road's main function is transportation, while streets facilitate public interaction.

Even with this clarification, though, I think you unfairly characterise the quote from the article. Modern society has an insane demand for transportation. Roads – the medium on which we transport things – are the fabric on which cities are built. Not just inside the cities, but the vast network of roads outside the city, that feed it.

Before the 1900s, we weren't able to build cities far from water because of their demand for transportation. We can today, and it is only because of roads we are able to do that.

I am a fun of Junxions my self which follow closely. But the approach in my system if very different. Junxions creator uses the same kind of node base/bezier shapes paradigm where intersections happen as node graphs and not automatically as collisions between road segments. It's hard to explain but I am planning to dive into more details on why those two approaches are different in my next blog deep dive.

https://www.reddit.com/r/Skookum/comments/47sbri/richard_fey...

I have a small list of these things in game dev. Over the years, I found some games that were more playable (in my opinion) than I thought they deserved to be. Kind of like a well written book with a bad story.

For me at least, the number one most important thing is how well the character -- person, car, spaceship, whatever -- moves. Does it handle well, as expected. I'm at the point where I think this may be the single most important aspect of a game that finds itself in a competitive space.

I think blizzard stands out for this with Overwatch and World of Warcraft. They avoid the jerky start and stops with their characters. Their characters feel both performant and natural at the same time, adhering to reality but breaking physics as necessary (air strafing for example).

Building out roads correctly feels like an offshoot of this for games which include cars. A car should be able to navigate a turn without going through weird contortions as it hits pinch points, or unnatural wiggles when roads join.

https://lizengland.com/blog/the-door-problem/

https://www.ign.com/articles/putting-doors-in-video-games-is...

But, to continue with the pedantry: the Romans already built cities far from (navigable) water. There have been roads since antiquity, then since the mid 19th century it was first the railways that made it easy to transport passengers and goods over large distances. The current version of roads being the main/only form of transportation only came about in the 1950s.

Incorrect.

In the 1800s the train took off as a primary form of transportation. By 1869, we'd completed the first intercontinental railway in the US which ultimately opened up the economy between the east and west.

Sears flourished as a company because of the train.

It wasn't roads which ultimately opened up mass transport, it was rail. It wasn't until the 1950s that rail was ultimately de-prioritized and roads were prioritized.

This is a very American point of view IMO.

Cities are built on streets first and foremost. Otherwise you end up with strip malls separated by endless swaths of car parks.

As for transportation, we have to separate cargo from people, and inner city from inter-city.

For people inside the city you have multi-modal transport options. Walking, biking, busses, trams, subways, commuter trains, taxis, individual cars, ferries.

For intercity people you have trains, planes, boats, busses, individual cars.

Most inner city cargo can be handled by smaller trucks going from warehouses to specific places in the city. And for smaller cargo like mail I've even seen small scooters and cargo bikes.

For inter-city you once again have multi-modal transport (depending on the city). Trucks, rail, cargo planes, boats.

Even the US was built on railways, not on roads. Roads are the "backbone of cities" only if you make them one, as the US has done

Bad/quick visual: https://pasteboard.co/5QgDdTVVSm1I.png

I live near the border with Germany, and these guys are used to short ramps and so just merge well below the speed other traffic are going, expecting others to yield. (And many locals also drive like that unfortunately.) So uncivilized.

These things are absolutely huge pieces of infrastructure that can take the space of dozens to hundreds of buildings.

A lot of that comes down to geography - the UK is a high-density population compared to the USA but the impact on our lives is significant. In the US, I would drive everywhere. Literally everywhere - to the shops, to the library, to the beach, everywhere. Yesterday I took my son to his archery practice, we walked along the coast road for about 20 minutes, and picked up a "Mr Whippy" 99er ice-cream (yes, even in the cold weather) along the walk back. It was pleasant, and healthier.

Why do you say it like roads are the only option? Its even far from the most effective option. You mean rails?

Embrace the next challenge: Instead of roads on parabolic (Euclidean) geometry, have roads on elliptic (non-Euclidean) geometry, like the surface of a sphere. Plus, on a sphere every line is already a circular arc anyway (no matter if straight or bent, the difference is just the center, radius and normals). Thus, this system of circular arc segments really lends itself to such a space.

Little prince style micro planets with their own miniature infrastructure will always have a special place in my heart. Half a year ago I started with laying out the basics https://github.com/Lichtso/bevy_ellipsoid_billboard https://github.com/Lichtso/bevy_geodesic_grid but got distracted by fixing some engine bugs in Bevy along the way. That reminds me I have to update to the newest engine version ...

anyway you can find some of the roads on spheres stuff here: https://github.com/Lichtso/bevy_geodesic_grid/blob/main/src/... it can not only generate the extrusion mesh but also calculate how the mesh overlaps with a geodesic grid of triangular tiles on the surface.

So the difference in scale between real life and the sims is 100% on purpose, as more realism makes the game worse. Just like they don't ask for a long permitting system for anything to get built, or demand a decade of discussion and probable lawsuits before you can move move a road, or rebuild an intersection.

They are visually very close because their curvature increseases approximately linearly along the curve but not exactly. Mathematically speaking if you wirte the cubic parabola as something like y = kx^3, the second derivative (which give the curvature) grows linearly with x which makes it behave similary in gentle transitions.

The problem is that the second derivative is not enough alone for having a true smooth curvature. The real curvature formula has in the denominator the first derivative as well (slope) making it not increase perfectly linearly along the curve. (denominator becomes larger and larger as x incrases)

But yeah, cubic parabola is basaically a good enough approximation. Might be a good solution for a system like this.

Sure, you have to have some facility with math to use clothoids, but I think the only other curve that will actually be simpler is circular arcs.

https://mastodon.gamedev.place/@TomF/115589925206309168

Beware if you post article's in there.

I also do graphic processing and now with ML, contact me if you ever want to share though, contact via my profile

Imagine an environment where ground/walls/ceilings always have gravity and one can build literal city mazes in horizontal and vertical directions. All that traffic going everywhere, oh my..

https://m.youtube.com/watch?v=PG4gr0Q4904

A "properly rounded corner" at an intersection as alluded in the article is one that's great for cars (as they don't have to slow down much or have a tight turn. However, they are awful as pedestrian crossings if you want to do a double crossing, as you have to traverse additional distance. They are also much more space-inefficient, which isn't viable in a densely built urban environment.

is in the name mon ami

Everything in the article applies equally to trains and rails.

We get enough complaining about evil car-centric city designs on the posts directly about cars thanks.

Results can be seen on f.ex https://www.openstreetmap.org/#map=16/55.88242/37.72732

In more simulation-focused games, cycling and walking paths are often available, and you can use them, but they come with many of the same constraints they face in the real world. In practice, that means they are usually not efficient as the primary way to move large numbers of people across a large city.

Reading your comment, it sounds like you want a game that is realistic in most respects, but treats transportation differently, in a way that makes your preferred options the optimal strategy. That is going to be hard to find, since transportation is a core part of city-building sims, and developers tend to pick either realism or a more utopian/fantasy model rather than mixing both in a single game.

That's because SimCity is not a tool for preaching your personal opinions of what makes "more livable cities" to people who more often than not want to design semi-realistic, typical cities in an entertaining strategy game.

If you want to make your perfect city builder, go ahead, it's easier than ever now for somebody to create a game. Just don't expect everybody else to share your view of "aspirational", more so if you actively punish traditional city structures.

Most people consider that a benefit. It's just as livable as anywhere else. Just different.

Neither US or Europe do living areas well due to their historical constraints.

https://humantransit.org/2013/05/how-sim-city-greenwashes-pa...

Using circular arcs or even simple third-degree polynomials (like cubic parabolas) reduces many of those operations to trivial O(1) function calls, which makes them much cheaper to evaluate and manipulate procedurally, especially when you're computing it 60 times per frame

The scale difference mentioned in gp isn't just doors though but any structure you can pass through. Many games houses with larger interiors than exteriors and video game ventilation ducts are comically large.

This made me briefly nostalgic for the old glory days of Slashdot, which is the first place I recall that would cause the "hug of death".

you need "plop the growables" and "move it" mods at minimum to nudge all the buildings close together.

https://thisweekinbevy.com/ https://bevy.org/news/

If you think Simcity and Cities: Skylines are realistic depictions, then ask yourself why Simcity famously has no visible parking whatsoever (or don't: the devs are on record saying they excluded it because it made the cities look terrible, there's no need to speculate here), or ask yourself why Cities: Skyline added car pokeballs (where drivers get out of the car and put the car in their pocket) or straight-up delete cars when traffic gets too heavy.

What you call "typical" and "traditional" is not in any way universal.

Or you haven't travelled a lot.

It's the opposite, no? Most city builders cheat to be able to be fun. Like, with the amount of roads one build in Sim City, half the map would have had to been parking lots to account for that amount of traffic. But that's boring gameplay, so they remove that constraint to make a fun game. Aka you never have to deal with the consequences of making your city car dependent.

Edit: See another comment from CalRobert about exactly this.

Cities Skylines with all the DLC and the right transportation mods gets pretty “realistic” in that you can build a transit paradise but the car still exists.

People are totally entitled to like what they like, and that's OK. Everyone has something that works for them, and this world has a great variety of options available but the "car-centric suburban sprawl" is linked to various negative mental and physical health consequences. Negative health consequences, IMO, isn't "just as livable".

As a simple example, when people walk more during commuting instead of drive, they tend to be healthier. There are other more nuance (but studied) impacts, such as increased car accidents, mental impacts from increased isolation, etc. In America, there is even a correlation between how car-centric a community is and how often individuals are willing to seek out healthcare (even when accounting for access and affordability).

https://imgur.com/a/procedurally-generated-buildings-that-or...

I wish they'd actually shown more/talked about it though.

Does that imply that the merge of two lanes is still too costly?

Also it seems the lane from south east to south west is missing :D it's somehow routed via north first and then goes around the circle.

And, of course, the fact that the areas you say "aren't better to live in" also tend to be extremely expensive doesn't make a lot of sense.

A well-built large city isn't just going to be 100% biking and walking paths, it's going to have streetcars, light rail transit, subways, and buses as well as roads with cars. The difference is that people shouldn't be forced to commute across the entire city to get to work because you decided to cram all of the commercial zoning into one downtown core.

https://raphlinus.github.io/curves/2021/02/19/parallel-curve...

https://levien.com/phd/euler_hist.pdf

My guess is a combination of tech being better and HN having lower volume vs peak /. (before digg&reddit).

The statement reversed, you might loose your joy because working in the game is no longer fun.

I get you but just want to say: careful what you wish for :)

Source: https://www.sciencedirect.com/science/article/pii/S026483772...

Yes.

This one https://www.openstreetmap.org/#map=16/55.88495/37.47959 was built from scratch not very long ago. Notice how merges/splits are spread as far as possible.

Isn't the point that they should be, if that's how I choose to build a city, and they don't have to be, if you choose to build it otherwise? The entire point of a sandbox city-builder is, I assume, that it's a sandbox, and not a dogmatic interpretation of a childish Reddit meme.

The number of places in the north american continent that retain their street focused infrastructure is pretty much countable on one hand, and most of that is being terribly managed.

A small errand that takes me 5 to 10min in my hometown takes me 45min to 2h in suburbialand. Worse, mutualizing errands do not even reduce the overhead of a single trip because infrastructure is usually made in such a car centric way that it makes it super inconvenient if not downright dangerous to walk from one huge parking lot to another one a couple of blocks away so you are kind of pushed to move your car, sometimes navigate a stupidly long loop to simply turn around and go on the other side of a stroad.

By the end of the day you realize you have barely done anything.

Funnily it makes it worse for both drivers and non drivers.

At home I usually opt to not take the car, not because it would be slow but because in many cases it is silly. It would be too short for the engine to even warmup and I would not have the chance to enjoy some time outside and/or exercise at the same time.

I totally see the impact spending so much time in the car and traffic has on my in law family's stress level and they do complain a lot about it while being seemingly unable to envision a better way of living and push for it at political level. It is also super bad on the security side of things because they often opt to take/make calls while driving for it to not make it time totally lost and aren't just as focused as they should be on the road.