This interview has been edited for readability. All imagery featured on this article is from an early construct seize and is not consultant of the ultimate sport.

“The highway is the place it began,” explains Colossal Order co-founder and CEO, Mariina Hallikainen, discussing how the interconnecting tracks of concrete and tarmac in Cities: Skylines II turned the “spine” of the city simulation the Finnish studio got down to construct.

After finding out how individuals interacted with the unique Cities: Skylines—which concerned poring over the mods that have been being created by the neighborhood—the Colossal Order group seen gamers usually used roads to basically sketch out their cities and create one thing akin to a central nervous system. It was a realization that satisfied the group roads must be much more accessible within the sequel.

“We had a transparent idea in thoughts when creating the highway instruments for the sequel,” says Hallikainen. “It needed to be simpler to make use of, and so we took numerous learnings from the unique sport and the wonderful mods that have been out there.” With that purpose in thoughts, Hallikainen mentioned the group began with a core pitch and branched out organically—excited about the forms of roads that have been included within the first title and their distinctive ache factors. “With the roads that we had within the first sport—there have been differing kinds like ‘bus lanes’—however now you possibly can improve roads and modify them [after they’ve been laid] so you do not have to have such an enormous variation of highway sorts which might be static as a result of you have got the instruments to switch them” she says.

Hallikainen notes that by drawing a transparent distinction between ‘roads’ and ‘highway instruments,’ Colossal Order was in a position to devise a system (by making a “tremendous ugly” placeholder) that may supply gamers the flexibility to maintain customizing and tweaking their cities without having to destroy and rebuild. That made devising the instrument itself extra (if not solely) easy, with the group specializing in permitting gamers to attract straight roads, curved roads, or complete symmetrical metropolis blocks onto terrain utilizing an intuitive drag-and-drop instrument without having to fret about what tweaks may want making as their metropolis evolves.

“Basically, we needed to have ‘roads’ and the ‘highway instrument,’ so you do not have to begin by considering what number of several types of highway you are going to want. That permits gamers to begin with a easy imaginative and prescient whereas we information them with helper traces that account for issues like steepness, angles, and crossings,” she continues. “We had an enormous quantity of assist from the neighborhood if you concentrate on how a lot suggestions we have obtained over the previous decade.”

In Cities: Skylines II, roads (however not highways) have additionally been given the flexibility to hold and disperse varied utilities like energy and water to buildings linked to them. Hallikainen says that change was a quality-of-life tweak designed to make the whole expertise extra accessible, eradicating the wants for “tedious chores” which may have beforehand required gamers to maintain constructing the identical factor again and again.

Complexity derived from simplicity 

Hallikainen says the prototype highway instrument that knowledgeable the system gamers will use in-game was one of many earliest issues Colossal Order created for the sequel, and describes seeing it in motion for the primary time—watching as roads snapped into place whereas robotically accounting for elevations within the terrain and different variables—as a “transformative expertise.” As impactful as that prototype was, it nonetheless required iteration.

“I believe the largest problem with the roads is that there are simply so many alternative methods to put them, so there have been an enormous quantity of visible glitches,” she continues. Hallikainen says that now and again, inserting a highway may end in “textures utterly exploding” or the creation of a void on the earth that result in “nothingness.” These are the sort of unnatural disasters which may go away each gamers and their digital residents barely mortified, and Hallikainen concedes the instrument was nonetheless a little bit “wonky” till lately.

“To have the ability to repair all of the circumstances the place issues can go improper was an enormous endeavor. I am fairly positive we’ve not solved all of these issues and we’ll in all probability proceed engaged on it for a really very long time,” she explains, noting that Colossal Order absolutely intends to maintain fixing points as they’re raised by gamers after Cities: Skylines II has launched. To this point, quashing these bugs has been the results of intensive QA testing.

“There are two forms of QA testing [we’ve used]. We’ve got individuals devoted to only making an attempt to interrupt the instrument, in order that they’re simply constructing roads in all types of the way. Then we’ve got playtesting, when some points might naturally happen after which we repair it,” she provides. Hallikainen believes that testing is maybe the “greatest” problem for a title like Cities: Skylines II, which offers gamers with an abundance of choices and freedoms. “It is virtually unimaginable to have [the game] 100% polished in a manner that eliminates all bugs,” continues Hallikainen. “What I’m anticipating is that we’ll get studies from gamers after they’ve gone hands-on with the sport after which we’ll proceed fixing these glitches as they seem—however I hope we have caught the entire most blatant ones.”

To offer you some context as to how a lot variation is afforded by roads alone, Cities: Skylines II gamers are in a position to create small roads, medium roads, giant roads, and highways. Every of these classes is available in a number of kinds akin to two-way roads, one-way roads, and different asymmetrical variations. There are additionally elevated variations of every roads, whereas connecting completely different sized roads can create distinctive intersecting choices—akin to the flexibility to create entry and exit ramps for highways.

Making that wealthy palette of risk accessible meant permitting gamers to basically outline their very own issue curve by making certain the only highway might go the space. “You’ll be able to select a highway sort and construct your complete metropolis with that and get town functioning,” says Hallikainen. “You will have some issues however the sport is kind of form to you at first. Then gamers may have the chance to be taught and begin to finesse.”

Hallikainen believes Cities: Skylines attracts two forms of gamers: those that really care about how their metropolis seems to be and wish to create an visible utopia, and those that focus solely on the simulation and wish to obtain city equilibrium no matter the associated fee. Guaranteeing gamers aren’t required to acquire an encyclopedic information of roads and all their kinds to create a functioning metropolis means they will indulge their very own specific whims. “For those who do not ever wish to construct an elevated highway, you do not have to. For those who do not wish to construct tunnels, you do not have to,” she says. “The thought is that you could begin with the fundamentals and start exploring no matter pursuits you—that is why roundabouts are a lifesaver for me. You’ll be able to simply drop them wherever and the site visitors [flow] turns into a lot smoother.”

The magic roundabouts

There’s it. The magic phrase. Roundabouts. Da Vinci had the Mona Lisa. Michelangelo had the Sistine Chapel. Shakespeare had Hamlet. Colossal Order has roundabouts. Unable to correctly implement them within the authentic title resulting from technical limitations associated to the highway instruments themselves and site visitors AI, the Finnish studio made mastering roundabouts within the sequel a “non-negotiable.” 

Chiming in briefly throughout a follow-up interview over e-mail, Antii Lehto, the programmer chargeable for making roundabouts tick, mentioned probably the most sophisticated facet of creating the function was producing the site visitors lanes “when roundabouts can have an arbitrary quantity and kind of highway connections.” He additionally defined that, within the authentic title, roundabouts merely would not have labored and not using a “large rewrite” as a result of together with them wasn’t even thought of a risk originally of manufacturing.

Studying from these previous errors, Hallikainen says Colossal Order virtually instantly started prototyping the instrument by how the site visitors AI and highway instruments might work collectively in a manner that was “smarter” and “extra grounded in realism.”

“We knew that for Cities: Skylines II we would have newer tech, so we might really spend a bit extra efficiency on the site visitors AI. That is one thing that positively performed a component within the constructing of the whole highway instruments,” she says, noting how when gamers construct roads they’re virtually making a “pathfinding” routine that can enable residents to maneuver round.

“Working from that, simply to have the only roundabouts required a bunch of concerns.” Hallikainen explains how changing a roundabout with a traditional intersection would necessitate modifications to the prevailing roads and the way they join. “It is extra concerning the visible illustration that required an enormous quantity of labor to make occur, as a result of the site visitors guidelines are fairly easy in actual life. The complexity comes from the visible illustration and getting the site visitors AI working in a better manner.”

On the visible entrance, Hallikainen says {that a} roundabout is kind of a singular form and dimension when contrasted towards most intersections, so making certain gamers might “plop” them in and modify belongings in a manner that also appeared pure (and did not break something) required numerous trial and error. Once more, it was about making an attempt to pre-empt a myriad of permutations. Would gamers try to put a roundabout on an incline or in the midst of a bustling enterprise district? Risk, as Hallikainen expressed earlier than, meant potential issues, however she’s assured the group was in a position to account for lots of these outcomes. “You’ll be able to place a roundabout on a slope and it should not break,” she reassures us.

As for the site visitors AI, having the ability to harness extra processing energy was an enormous win and helped deal with one of many large criticisms leveled on the authentic sport. “I keep in mind with Cities: Skylines we had a participant ask ‘why cannot the site visitors be smarter, it is only one line of code?’ And we have been like ‘sure, however, while you put that line of code within the sport will not run anymore,'” she says. Outlining what makes the site visitors AI smarter this time round—and due to this fact able to understanding what proper of manner means when confronted with a roundabout—Hallikainen explains that vehicles can now change lanes or reroute themselves in transit.

“Now there are site visitors accidents that may block a whole roads, and the vehicles will not merely disappear like they might within the first sport—the place in the event that they noticed there was no manner out they might simply vanish and find yourself at their vacation spot, which was basically our failsafe,” she continues. “Within the sequel the AI is smarter in such a manner that they will alter their route, so when there’s an accident or site visitors jam they will change lane and even do a u-turn and discover one other manner. 

The truth that innovating on advanced instruments and programs like these current in Cities: Skylines II may additionally imply delivery a venture might be perceived as considerably janky was tough for Colossal Order to simply accept. Hallikainen says the ambition is at all times to have as a lot polish as attainable, however admits that with the “variations” current within the highway system particularly, “there are numerous issues that may go improper.”

“You need to settle for that,” says Hallikainen. “That is why we’ve got producers who aren’t artistic. I believe it is necessary to have that assist within the studio. To have individuals who say ‘it is okay to cease sprucing sooner or later’ and you need to simply let it go. You need to get the product on the market, and with us having the mentality that we will work on this sport for the lengthy haul. We’re extraordinarily keen to begin listening to the suggestions from gamers so we are able to hold iterating.”