To paraphrase the article, this is what urban planners have nightmares about. Roads (as in: things made for cars) aren't the fabric of a city, streets (as in: things made not only for cars, but also for pedestrians, cyclists, public transport etc.) are. See also: https://en.wikipedia.org/wiki/Stroad
> 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.
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.
You can see it in one of his examples where the bézier curve has an inflexion point which crosses over itself on a sharp bend. I ran into this while writing Azoth [1] last year, when wanting to be able to overlay paths with blending into the background at the sides, and curving around existing features on a game map. To solve the problem, I simplified it, and there's an (animated) example of how I got it working here [2]
[1] https://github.com/ThrudTheBarbarian/Azoth
[2] https://github.com/ThrudTheBarbarian/Azoth/blob/main/Documen...
The subreddit is here: https://www.reddit.com/r/Junxions/
Sure they teased that they've made their own solution, but I think Junxions should scratch the itch of most of us here interested in this kind of game.
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.
Finally, I am part of the 1%!
I've been playing Kingdom Come 2 of late, and I find it's natural to just kind of take the world they've created for granted - just like we do the real world. But when you actually stop and look you have to consider that every one of the finely crafted details was built by someone's sweat and tears, be it artists, programmers, or designers at edit time.
No wonder it's an industry of crunch, the work involved can be uniquely daunting.
https://lizengland.com/blog/the-door-problem/
https://www.ign.com/articles/putting-doors-in-video-games-is...
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.
For now all I have to share is this explainer I made some years ago: https://xixixao.github.io/euler-spiral-explanation/
Author please keep writing.
The cities I find the most interesting (for roads) are the ones which kept gridding out in new directions to follow the course of a river. Cities like Buenos Aires, New Orleans, and Saigon, where the original paths followed curves around the river bends, resulting in multiple intersecting grids.
The intersections and division boulevards between grids are, of course, the most beautiful and architecturally interesting parts of any city. They are where the blocks are strangely shaped and the buildings can't be rectangular, and usually where every inch of land is at a premium as well. It would be nice if a city-builder could simulate that aspect of urban growth: The shift from village center to grid, and old grid to new grid.
Some manager at Google should have gotten an appraisal for removing proper curves from Maps, because... who cares, they do not need them on US streets.
Of course the Romans didn't give a shit who's property rights they might be violating. I live in Lincolnshire UK, where Roman roads are still used. The last one that got changed was years ago when they had to put a kink in Ermine Street (now the A15) at RAF Scampton when they extended the runway to accommodate Vulcan bombers.
Related: https://www.pushing-pixels.org/2014/04/04/the-craft-of-scree... (The craft of screen graphics and movie user interfaces - interview with Jorge Almeida...)
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.
Very nice article - good read !
Wonder if cubic parabola (used by some railways, and visually near indistinguishable from clothoid) has easier maths.
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.
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
I've been trying to make this as easy as possible for non technical people to draw terrain in craftmygame (the game engine I'm building) here's what the terrain painting looks like in the editor so far : https://youtu.be/bFrUYM2t3ZA?si=tw1LqBWR7Uyn08lR&t=37
https://github.com/chrisdiana/TinyCity/blob/6c3a7337788655b5...
Road and rail curves are massive and it’s hard to understand just how big they are without having to actually walking them.
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.
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 :)
> Do 99% of city-builder players care what shape the corner radius of the intersection has? Most likely, no.
Maybe not... but out of all the players who care corner radius of roads in games, 99% of them probably are into city-builder!
I wish they'd actually shown more/talked about it though.
One of the biggest problems with North American cities is their endless, car-centric suburban sprawl. SimCity games may be really fun to play but they seem to reinforce this problem and anyone who grows up playing them will not learn about alternatives for more livable cities.
New Urbanism, traditional neighbourhood design, streetcar suburbs, one-way streets, bike paths, walking paths, mixed-zone walkable villages (light commercial with residential), smaller single-family houses and duplexes, triplexes, houses behind houses. Many of these are older and more traditional techniques to yield higher density neighbourhoods without building up to large apartment buildings.
It would be really cool to see a game that focused more on creating these kinds of realistic and aspirational living spaces instead of the usual cookie-cutter suburbs linked up by huge roads and a large downtown core.
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.
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.
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.
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.
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.
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.
Neither US or Europe do living areas well due to their historical constraints.
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.
https://humantransit.org/2013/05/how-sim-city-greenwashes-pa...
you need "plop the growables" and "move it" mods at minimum to nudge all the buildings close together.
Most people consider that a benefit. It's just as livable as anywhere else. Just different.
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).
Compare that with the sprawl of Vaughan also shown in the video [1].