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An Interview With Oskar Stalberg — Weblog

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Townscaper is a small recreation, with massive ambitions. A metropolis builder wherein gamers can merely add or take away a block from the sport world. With this restricted toolset, you may craft all the pieces from idyllic seaside cities to a horizon spanning metropolis. A procedural technology engine working beneath the hood caters to the distinctive topographies gamers set up and refines the world with every new motion taken. However how is it able to increasing, and rebuilding the world with such consistency? Whereas additionally introducing enjoyable and novel concepts for gamers to find on their very own.


For this case research we’re going to elucidate the completely different degree technology methods that energy Townscaper and the AI ideas they derive from. Plus I sat down with the sport’s creator Oskar Stalberg to achieve a stronger understanding of the way it all works and his aspirations in designing the sport. So as to actually perceive Townscaper, we’ll be taking a journey via Stalberg’s profession and his earlier work. As a result of the secrets and techniques to the sport’s success are hiding in plain sight, in all the pieces else that he has constructed thus far.

Townscaper Defined

First launched on PC and Mac in June of 2020, Townscaper is, by Stalberg’s personal admission, extra of a toy than a recreation. It doesn’t have any explicitly outlined aims and as an alternative, you’re left to craft cities based mostly by yourself design ideas. Gamers have a really restricted variety of interactions: you may determine the place a block is added or eliminated, and you may customise the color of the blocks you place. That’s it. Every part else that you just see, is achieved courtesy of the sport’s procedural technology system. This creates what we’d usually contemplate to be a mixed-initiative AI system: which means that the participant offers enter to the place the sport must broaden the construction, and the system assesses the present form, identifies what prebuilt chunks of structure are legitimate for that area after which injects them into the sport world. Regardless of this lack of direct management, the system is very versatile and may deal with a myriad of various situations that gamers can provide you with, leading to a wide range of enjoyable, fascinating and aesthetically diverse settlements.

And it’s this simplicity in gameplay mixed with the sport’s brilliant, summary but detailed aesthetic, that has led to Townscaper transcending boundaries: creating an enormous following throughout social media that has captured the imaginations of many who don’t usually play videogames. Plus when you’re a recreation developer on Twitter, you’re sure to have seen considered one of Stalberg’s growth tweets in your timeline. Both for Townscaper, his earlier recreation Dangerous North or his newer tasks.

The key to Townscaper’s success is one which many aspiring (and present) recreation builders ought to replicate upon. The sport is successfully the fourth entry in a sequence of works that capitalises on Stalberg’s curiosity and rising experience in procedural technology and technical artwork, with every challenge constructing upon the earlier one. And to efficiently clarify the tips employed in Townscaper, we have to return and go to every of them in flip.

“I really feel like I’ve form of been engaged on the identical factor for the previous ten years or so. However it’s additionally form of enjoyable as a result of as an alternative of turning it into one large epic factor, I’m making a small factor at a time. Launch that after which make a barely greater factor with some new expansions, launch that. So it’s a fairly great way of working: form of releasing the intermediate steps of your challenge since you study lots from entering into the transport mindset and wrapping issues up.”

Oskar Stalberg

So with this in thoughts, we begin our journey in what’s arguably an surprising and unlikely place. The sport that impressed Townscaper and all the pieces that preceded it: Tom Clancy’s The Division.

Brick Block

“After I made BrickBlock and a few different, like, procedural toys. These weren’t industrial tasks, however simply ending them and placing them on-line for different individuals to make use of was a very great way of entering into the transport mindset, ensuring, , I do some UI and possibly some sounds and stuff like that.

Whenever you get into the transport mindset, you begin to form of see your issues from form of one other individual’s eyes. You begin excited about your factor as when you got here to it the primary time. It’s very exhausting to try this while you while you’re not in that mindset, while you’re simply increasing and increasing. However then while you begin to consider, “Oh, I even have to indicate this to different individuals”, after which I want to repair these couple of issues, and I can really reduce out these couple of issues that I used to be planning on doing as a result of one other individual gained’t know that these issues are lacking.”

Oskar Stalberg

Stalberg graduated in 2012 from The Sport Meeting, a faculty specialising in recreation growth based mostly in Malmo: arguably the largest hub of recreation growth studios in Sweden. Not lengthy after, he landed a job at Ubisoft’s Large Leisure, creators of Tom Clancy’s The Division, working as a Technical Artist. The Division takes place in downtown Manhattan, an space comprised largely of tall skyscrapers and ominous-looking buildings. Whereas Stalberg wasn’t concerned on this a part of the manufacturing – his work was really on the very cool trying holographic map – he watched his colleague’s work on town constructing group with nice curiosity.

“They wanted a number of buildings so that they made some instruments to assist make the [them]. After which I began excited about how I might strategy making the constructing instruments. I wished to consider it as a result of there’s the usual approach which I believe is form of how they [Massive] did that as nicely. You make a polygonal form and you then extrude outwards and you then simply duplicate modules alongside the partitions.

And that’s excellent for many issues. Most life like homes anyway. However I assumed, okay, however what if homes have barely weirder shapes? Like one of many it’s not simply form of 2.1 dimensional, however like wall goes like this after which up and like that. Like, how do you account for these form of shapes? And since a form of a key concept in most of my procedural work and form of inventive work normally, my key philosophy or strategy that I’ve is that what’s essential is what occurs when issues change. So what occurs when one materials meets one other materials? What occurs like on the nook of a home or the nook of the wall on the roof? And issues like that. As a result of like while you simply have the identical brick wall, that’s not that fascinating.

You must have a pleasant brick texture, however in all probability a refined one. However what occurs when the shapes change? And that’s like when you wished to make a home with a wall that goes like flat then up after which flat once more, like that little nook; you’d wish to artistically touch upon the factor that occurred there.”

Oskar Stalberg

This led to a small however important query that may drive the creation of Townscaper: the right way to construct city constructions that respect the native topography. The reply was a small prototype referred to as Brick Block: wherein gamers can place blocks inside a hard and fast 5x5x7 grid that permit for small, but enjoyable trying city environments to be constructed. As you may see, Brick Block glues collectively items of house buildings collectively in ways in which make sense.

To make this work, Stahlberg constructed a device that’s markedly related to what’s generally often called Marching Cubes: an algorithm constructed for the needs of producing a polygonal mesh inside a specified three-dimensional quantity. By discretising a grid area right into a sequence of factors, you may create a polygonal mesh utilizing choose factors inside that 3D area. Technical complexities apart, what this implies is that by deciding on a number of factors in area you may draw a 3D form. In Brick Block the sport solely lets you construct a brand new unit supplied the cell chosen connects to polygons already constructed in neighbouring cells. This prevents rogue blocks from floating in area, however can nonetheless permit for constructions that may make a civil engineer escape in a sweat. Nonetheless, the important thing factor, is that provides gamers a number of freedom to make fascinating and enjoyable constructions.

The origins of Townscaper are clearly evident right here, however it was shelved in the intervening time. Whereas Stalberg struggled with the right way to take this concept and switch it right into a fully-fledged recreation, the large technical subject was that Brick Block constructions shortly change into repetitive. Therefore within the demo you may play on-line, a aware resolution was made to maintain the grid very small. Therefore there was a brand new query to sort out: how might you strategy the identical concept on a bigger grid whereas enabling extra range within the generated output?

Dangerous North & Wave Perform Collapse

Stalberg left Large Leisure in 2016, not lengthy earlier than the discharge of Tom Clancy’s The Division and after a stint on the Malmo studio of Monument Valley developer UsTwo Video games, transitioned into indie growth. Working alongside colleagues Richard Meredith and Martin Kvale, this led to the creation of the micro RTS fight recreation Dangerous North, printed by Uncooked Fury and launched in 2018.

In Dangerous North gamers are offered with the problem of defending small islands with village constructions that may be attacked by Viking invaders. To allow the roguelike components of the sport, the sport procedurally generates every island previous to its showing on the sport world map. However in contrast to Brick Block, which wants solely create one thing aesthetically pleasing, Dangerous North had the added problem of satisfying a myriad of gameplay capabilities. Every island wants to offer adequate actual property for the motion of armies, massive coastlines that can allow all the invading forces in that degree to seaside efficiently. And critically, the flexibility for participant and enemy AI characters to have the ability to transfer from one space of the island to a different efficiently.

This time round, the ensuing resolution wanted to offer a number of selection, whereas making certain logical consistency. And it’s with this in thoughts, Stalberg drew inspiration from Wave Perform Collapse – an algorithm that can be utilized to determine what objects will be positioned subsequent to one another based mostly on the foundations supplied to it. Wave Perform Collapse is what in AI phrases we name a constraint solver. Constraints Solvers are a category of AI algorithms designed to unravel issues wherein variables will be assigned a myriad of potential values, however there are guidelines on what values will be assigned, and people guidelines can have an enormous chain response on the ultimate resolution. A easy, but very efficient instance of those constraint satisfaction issues, is a recreation of Sudoku. In Sudoku, every cell can solely have one worth between 1 and 9, and the foundations of the sport add constraints that inform us that no quantity can seem twice in the identical row, the identical column and within the outlined 9×9 subsquares. The aim of an AI Sudoku participant is then to make sure that each new digit added to the grid satisfies these constraints, but in addition doesn’t stop different cells from having any legitimate numbers left to assign themselves.

So what’s this received to do with Dangerous North? The algorithm Wave Perform Collapse, developed by Maxim Gumin in 2016, is designed to create massive 2D graphics utilizing the identical precept. The concept is that upon studying a smaller picture, it learns what are the legitimate guidelines for producing new photos of its personal, of any measurement. The unique picture highlights adjacency constraints, which means that for any pixel within the graphic, we are able to shortly decide what legitimate pixels will be positioned subsequent to it. Stalberg was impressed by this concept and sought to construct a 3D model of this. It’s price noting that the implementation in Dangerous North is bespoke, and it isn’t the primary time Wave Perform Collapse has been tailored for 3D. Actually, Wave Perform Collapse is markedly much like an present algorithm referred to as Mannequin Synthesis, developed by Paul Merrell in 2007, which might obtain the identical factor for each 2D and 3D shapes.

To ensure that this to work in Dangerous North, adjacency guidelines have to be established by assessing every of the person chunks of 3D terrain often called tiles. There are over 300 tiles in Dangerous North – be it rock faces, stairwells, seashores, cliff edges and extra – that are first constructed within the 3D modelling device Maya. When imported into the Unity recreation engine, the perimeters are scanned to ascertain the place different tiles might conceivably connect with them. So for instance, a nook tile for the shoreline might be related to increase the shoreline, again away from the coast into the island itself, or the coast doesn’t lengthen in any respect and easily turns into water. By finishing this course of, it allows for the Wave Perform Collapse to know what tiles can be found in any explicit cell of the sport world grid, based mostly on whether or not adjoining cells had been additionally populated on the X, Y and Z-axis. However in fact, to ensure that it to work, there are some further guidelines such that the maps make sense and so they assist fulfill the gameplay.

Upon producing, the sport at all times assumes water on the backside and sky on the high, after which, it fills out the grid by seeding all of the potential tiles that might slot in every cell. Consider this because the risk area: all potential islands that the system might generate. This already imposes some constraints given the pre-determined measurement of the island, given seashores, cliff edges or different terminal edges imposing on the boundaries of the terrain. Some hardcoded constraints are additionally added to ensure the islands look extra life like, slightly than one thing that’s clearly procedural. This typically means two tiles which are the identical, or some tiles that replicate or mirror each other can’t be positioned subsequent to one another. Plus there could also be level-specific constraints based mostly on particular tilesets which might additionally affect the likelihood area. What can velocity this up is there are some tiles which are designed to cowl two cells within the grid, which may help scale back the grid-like outputs given they’re manually crafted and assist reinforce a key aesthetic. However in the end, the bigger the map, the longer this all takes to execute.

As soon as the primary tile is positioned in a cell, the likelihood area begins to alter. Usually the technology begins with homes, given all ranges want homes for gamers to defend. As soon as a single home is added, the likelihood area will start to shrink. It’s because the constraints of the wave operate collapse algorithm are rolling out from these positioned tiles. If a constructing has been positioned excessive on the island, then that imposes a necessity for land to encompass it, which in flip will impose additional constraints on the necessity for connecting terrain that can finally hyperlink right down to the seaside.

The true problem that Dangerous North faces in comparison with Brick Block, and even Townscaper, is that the degrees must fulfill gameplay wants. The generator doesn’t comprehend it’s making a degree for a technique recreation, it’s simply attempting to make a pleasant wee island. Therefore there are two key facets to Dangerous North’s Wave Perform Collapse implementation that don’t exist within the different video games. To begin with, there’s a want for the enemy troopers to have the ability to navigate from the seaside to the homes so as to assault them. And certainly to your forces to have the ability to go mess them up. Usually, we require a navigation mesh for NPCs to know the right way to navigate from one level to a different. They’re pretty frequent in recreation engines akin to Unity and Unreal. However you may’t depend on a navigation mesh for an island that isn’t technically constructed but. So how do you guarantee there’s at all times a path from the seaside to the homes?

“So every tile that’s being positioned is aware of its navigability. So principally, like, the place can you progress out and in of the tile? It was form of this one thing I added fairly late in Dangerous North so it’s not correctly built-in. So it at all times assumes {that a} tile is solely inter-navigable. In order that like when you can are available in on one facet and the opposite facet [then] you may go between. However that’s not at all times true. Generally there’s a wall contained in the tile. Earlier than I got here up with [the navigability system] it seemed to be troublesome to do the technology stay. And we had been excited about form of giving up on doing that and doing in all probability a listing of curated seeds or one thing like that.

So we’d generate a bunch of issues after which save the seeds. I believe that concept would work however it doesn’t really feel very interesting. Like when you’re going to do technology, do correct technology. As a result of what would occur then, is it will generate ranges the place you couldn’t go from one facet to the opposite. There could be a number of homes on the extent, however you couldn’t go from one home to the opposite. After which that degree isn’t actually playable in Dangerous North.

However this navigability heuristic made it intentionally generate islands that had been, that had been correctly navigable, the place you would go between all of the completely different locations that you just wanted to go. There might nonetheless be areas that weren’t navigable, however we’d know that there wouldn’t be any homes on them, for instance, as a result of it wouldn’t place the home tiles if it wasn’t navigable. And yeah, on these unnavigable areas, we’d as an alternative place forests, which was a superb resolution as a result of it made it visually apparent which you can’t go there. And it’s at all times good to get some good forests in, simply visually.”

Oskar Stalberg

Secondly, there’s a must run a validation test when islands are generated. That is to make sure that the extent goes to fulfill all the necessities and truly be playable. Whereas there are guidelines on tile placement that should be adopted, which we’d usually name a ‘exhausting constraint’, there are additionally ‘mushy constraints’, that needs to be adopted however have some flexibility. If an island isn’t going to have the ability to fulfill constraints, then the generator will restart. To do that, the generator saves the state of the island as soon as the preliminary constraints and risk area are established and may reset again to that time when needed.

“It very a lot is determined by the dimensions of the island and the tileset getting used and the way… like taller islands are way more troublesome as a result of they don’t have any cliff faces. So that they get extra cliffs on the ocean. Small and tall islands are essentially the most troublesome, principally. And in addition in Dangerous North in fact, like in later ranges, I must land extra ships in order that I want an even bigger longer seashores.

In order that additionally. So like if it’s if it’s a skinny however tall island that wants a number of ships, that’s going to be actually troublesome as a result of there’s only some methods that may appear to be, you want all these little slopes happening all the best way right down to the ocean and you then want a number of seaside there.

So yeah, and a number of the tilesets fail greater than others. The wave operate collapse is fairly dangerous for lengthy, skinny issues. So issues like partitions, like pipes and issues like that. It’s good in the event that they’re at all times allowed to finish or have junctions, then it doesn’t actually matter. However these however then it doesn’t actually look that good since you need partitions to go from someplace to someplace, not similar to out of the blue finish or no matter, as a result of then all the pieces simply seems too random. However with these form of tilesets they’re dangerous in and of themselves and fail typically. However then additionally, since my navigability system didn’t take correct account of that, these tiles may not be fully inter-navigable or intra-navigable I suppose, then yeah these would fail very often. So yeah, it appears like even to today, in Dangerous North, occassionally you’ll get a degree that fails as a result of we attempt to generate them earlier than you get to them, however often you’ll get a degree that appears damaged, and it doesn’t actually load. When you wait for a very long time,it’s going to generate after a bit. However yeah, that’s form of a failure that’s nonetheless there. Yep.”

Oskar Stalberg

As soon as the technology is full, the islands are merged into one mesh to minimise draw calls and graphical overheads, and its good to go. The method of bringing this collectively, from preliminary idea via to completion, took round 2 years to finish. However the outcomes communicate for themselves, with the system able to constructing myriad difficult gameplay environments whereas fixing the issue that Brick Block confronted, in making certain higher range and selection within the generated output.

Irregular Grids

Now there’s one final piece of the puzzle to contemplate: each Brick Block and Dangerous North function on sq. grids, however Townscaper doesn’t. Actually, the grids are irregular and look lots much less inflexible than in earlier video games. This was a aware resolution on Stalberg’s half, so as to create extra pure and life like geometry that respects the bizarre and winding methods wherein actual cities are constructed.

The inspiration for this got here from Oskar briefly working as a developer on Night time Name: a noir journey recreation developed by MonkeyMoon and BlackMuffin and first launched on PC in 2019. In Night time Name gamers assume the position of Houssine, a taxi driver in Paris who solves a homicide thriller via interactions with passengers. The map of Night time Name is derived from publically out there knowledge of town, which means you drive via town in a practical style. However all the conversations within the cab, depend on a completely three-dimensional illustration of town being rendered within the recreation. To handle this, Stalberg developed a device to deform grids such that they higher match the shapes of metropolis blocks after which generate easy constructing constructions inside them. Whereas not excellent, it greater than providers the wants of the sport, however it left an open query, of the right way to take this concept and apply it to a completely procedural surroundings.

“Night time Name was my first likelihood to attempt a bizarre grid like that. I don’t bear in mind the place the concept initially got here from. I imply, I had been pondering for a very long time about like, how would you make extra natural cityscapes and the way would you mix the strengths you get from tile-based issues. However tile based mostly issues are actually good as you get to design all of the little particulars that go into them.

So to get the handcrafted look, they need to be standardized. So how do you mix that with in the event that they’re standardized, they in all probability have to be right-angled. And I used to be very fascinated by this concept as a result of, you may take any topology, any 3D mesh and switch it into quads. It’s at all times potential. So I used to be actually fascinated by this concept that any graph might be on a quadrilateral graph.

Yeah. So we’d have an concept behind my thoughts for a very long time. After which, yeah, it first got here collectively, in Night time Name, after which I already had the concept that I’d prefer to discover this mix. And in Night time Name I form of received to check it. And I noticed in Night time Name that it turned out significantly better than I anticipated, like in Night time Name, they’re way more skewed than they’re in Townscaper as a result of I’m constrained by the precise avenue networks. Like if there’s an excellent bizarre angle there. I’m constrained by that. However from the road degree, you may’t actually inform in any respect. You may skew the items like rather a lot earlier than it begins to change into an issue.”

Oskar Stalberg

So how do you go about producing aperiodic infinite deterministic irregular relaxed quadrilateral grids? I imply it was a good query and never one which many had solutions to. The course taken was impressed by Amit Patel of Pink Blob Video games and his explanations of Hexagonal Grids (that’s one other hyperlink within the description for you). Utilizing this strategy, Stalberg got here up with the concept of taking a hard and fast hexagonal grid, breaking it up into quads, then breaking it up into quads once more after which shifting a number of the factors throughout the grid. And so with this remaining piece of the puzzle, we are able to lastly handle the title of the episode.

How Townscaper Works

The key of how Townscaper works is that it’s the fruits of all the pieces that preceded it:

  • It procedurally generates the quadrilateral grids impressed by Night time Name to create a extra life like irregular placement of buildings and constructions.
  • The Wave Perform Collapse of Dangerous North is used to find out what constructing tiles can be found based mostly on the form of the surroundings the participant has created.
  • And lastly, as soon as tiles are chosen, it makes use of the marching cubes of Brick Block to position them in such a approach that they are going to match the irregular grid.

However combining all of those concepts isn’t as simple as I make it sound, taking round 3 months to go from an early prototype to a working implementation. The true contribution that Townscaper brings is how the position of constructing components works. On condition that the sport now runs on this extra triangle-based grid – permitting for a extra European aesthetic to city development – putting cubes and cuboids into that area is now not simple. Therefore the Marching Cubes algorithm permits for tiles to be positioned in ways in which finest match the form of the grid cells given it focuses on the right way to place the corners of buildings. This in flip had an affect on how the tiles are constructed, with them now not being full chunks of constructing, however slightly nook segments that may be extra simply put collectively to create shapes that match throughout the cells.

The Wave Perform Collapses operates much like earlier than, however now it’s optimised for working in real-time. In Dangerous North, the algorithm would solely generate islands previous to the participant attending to work together with them. To drag this off, the ornament of a tile is separate from when it’s generated. What this implies is that the exhausting a part of the method is finished first: when a brand new piece is added, the Wave Perform Collapse identifies the potential modules for that cell, after which afterwards it’s going to enhance it. The location of a brand new block forces the remainder of the prevailing construction to re-evaluate, to ensure constraints are happy and likewise for brand spanking new alternatives to emerge given a block has been added the place as soon as there wasn’t one, but in addition when a block is eliminated, new constraints have been positioned on all the pieces round it and so they need to respect that change.

As soon as the likelihood area is recognized, it then works on drawing within the chosen items. That is why you may generally see a block seem, after which the element fills in a short time afterwards. Actually, as constructions change into bigger and extra advanced, you’ll discover the delay between block placement and ornament will increase. That is in the end a efficiency overhead of the algorithm: given the bigger a construction turns into, one change ripples via the complete related space because the Wave Perform Collapse has to reassert that all the constraints are being revered, and an acceptable tile has been chosen.

“In Dangerous North, if the algorithm fails, I simply restart the complete factor. However in Townscaper, it’s really allowed to fail silently. After which I simply it simply notice that there’s no approach these two items, these two cells might have modules that match collectively completely. So then let’s simply ignore it. So often you will notice. I believe the primary place the place that occurs is with the metal help constructions. And once more, it’s lengthy, skinny issues which Wave Perform Collapse isn’t that good at, you may see like unfastened hanging metal constructions that aren’t correctly related to.”

Oskar Stalberg

Talking of ornament, there are a number of further quirks in Townscaper that function on completely different ranges. You’ll discover home windows, chimneys, bushes and benches seem round a just lately positioned block. But in addition, you’ll see extra bespoke city structure seem relying on how the extent is constructed, leading to all the pieces from luscious gardens to stairwells, statues and even bizarre floating buildings.

These are all a part of Townscaper’s Wave Perform Collapse: the decorations on particular person tiles are smaller-scale patterns designed to replicate the topology: what area is out there across the positioned block after which putting props in opposition to the surfaces. That is very helpful for the likes of home windows, on condition that Stalberg makes use of a stencil buffer to chop them out of the mesh after it’s positioned, slightly than having the home windows within the tiles themselves, given there could be many edge circumstances that crop up resulting in home windows being reduce in half or caught on corners.

In the meantime, the extra fascinating and distinctive degree segments that may seem, are often called recipes. These are additionally hidden deep within the Wave Perform Collapse and are assigned a a lot greater precedence than different patterns. They’re meant to be found by curious gamers and reward them with one thing enjoyable and distinct. However, their precedence within the algorithm ensures they’re predictable sufficient in order that gamers can then reproduce them after they want.

“I assign precedence to all of the completely different modules, and the backyard modules are tremendous excessive precedence, however they solely they’ll solely exist. Like the one fringe of backyard items I’ve is the place they find yourself subsequent to a wall. So principally, until you construct a wholly enclosed space, there’s no approach to place the backyard items in any respect. In order that’s how that rule is created.

And that’s additionally why it doesn’t matter how massive it’s you’re constructing, it nonetheless works In order that’s how all of the completely different guidelines work. It’s a little bit of a bizarre approach to design the foundations, and you actually need to get into the pondering of it. And it’s fairly, it each creates some fascinating alternatives of guidelines you may have, however it’s additionally fairly restricted in what guidelines you may have.

However with the backyard, for instance, prefer it additionally limits, because the backyard then is principally two dimensional as a result of it will possibly solely exist in an enclosed flat space. It additionally limits the quantity of items I wanted to construct to make the backyard work. As a result of it’s an fascinating each technical problem, but in addition design problem, like how do you create these guidelines in a approach, that they play properly with the Wave Perform Collapse algorithm, but in addition in a approach that in order that they really feel like a participant can learn the way the foundations work. In order that they form of ‘get’ why the backyard seems or it doesn’t seem for instance.

I need the bigger shapes to really feel very predictable, however the smaller shapes are allowed to range fairly a bit. So there’s at all times going to be a backyard when you make an enclosed space, however then the partitions, for instance, that run within the backyard, the little stone partitions, they are often fairly completely different. However there’s additionally guidelines for the right way to make them seem as a result of the one seem at like corners of homes or when you change the colors of homes. So it’s form of form of made to appear to be there are completely different properties which may have their very own lawns. So it’s like division between the plots. So yeah, I need the person to really feel like they’re in charge of the massive shapes. However then I get to mess around with a number of issues on the small shapes.”

Oskar Stalberg

And whereas that is the majority of the particular technology course of, there are many smaller concerns made to assist make every city look extra alive, but in addition guarantee it continues to be readable at a distance. There are actually easy AI birds and butterflies, which merely anchor to a recreation object in proximity, after which often fly round it, and react to native geometry. Plus optimisations to the rendering to minimise aliasing and guarantee outlines of shapes and constructions proceed to look crisp but detailed at any angle or distance.

Given the construction of the algorithm, it’s possible that Townscaper might be re-skinned, by creating completely different tiles that replicate completely different architectural moods or themes. Nonetheless, to take action wouldn’t solely imply making someplace within the area of 500 tiles, however it will detract considerably from the unique inventive imaginative and prescient.

“So initially, it matches the Scandinavian [theme] fairly nicely as a result of it’s form of like Copenhagen, Stockholm, and Aarhus as a result of it’s colourful and it’s a good vernacular. It’s a bit element, however it’s not tremendous detailed like in like northern Germany or additional south, you will get equal seems like very lovely, additionally colourful issues. However there are much more decorative and decorative is gorgeous in actual life. However within the videogame nicely, they’ll see extra polygons and stuff like that, clearly. But in addition while you zoom out extra, it begins to look a bit cluttered. Tough technical options in any other case, when you don’t need like a bunch of aliasing or no matter, when you zoom out.

So, yeah. And in addition, it permits you because the participant to challenge extra of your personal concept of what sort of element this might in all probability have as a result of it’s a little bit of an summary illustration from the start. However yeah, I imply, that’s clearly one of the crucial frequent factor that individuals request from. It’s, Oh, I need this, however in Japanese or in futuristic type or one thing like that, and that may in all probability be a good suggestion commercially, however it’s to me it’s simply not a really fascinating drawback. Like, I don’t wish to spend… constructing this complete tileset takes a number of time. And it was actually enjoyable to try this as soon as and resolve these aesthetical issues and the technical issues on the identical time and determine this complete factor out. However as soon as I’ve completed it already, I don’t wish to spend like two months doing the identical factor once more with the Japanese twist to it.”

Oskar Stalberg

Having now been launched on Steam, Swap, Xbox and cellular, Townscaper has achieved a large following and what was as soon as a facet challenge Stalberg might take pleasure in for a time because of the success of Dangerous North, has confirmed to be much more profitable. With a group of gamers who share their works on-line, and even create 3D printed variations of them because of a characteristic within the Steam model that permits you to export your cities to 3D mannequin recordsdata. And whereas Stalberg was satisfied it will develop a following because of that preliminary enthusiasm on Twitter, it has definitely caught him unexpectedly.

“It was at all times going to be one thing I used to be going to launch. The purpose of Townscaper, it actually was as a private experimental challenge, and I didn’t suppose it was going to be commercially profitable, however it was tremendous commercially profitable. And I additionally thought the… as a result of with Townscaper I even have a writer for it Uncooked Fury. It’s the identical as with Dangerous North. However once I first launched it, I wished to, , simply undergo the entire expertise of launching it myself.

So I did launch on Steam myself simply to see how that works and the way that felt and see like, , how and likewise see how far does my, simply my very own private advertising and marketing attain, for instance. However I imply, the Twitter interplay was additionally, I imply, performed a task in that. I shortly observed once I began posting Townscaper issues that, like my follower account shot up rather a lot, like on the finish of Dangerous North, I believe I used to be like one thing like 20,000 followers on Twitter.

After which on the finish Townscaper, I used to be like, it’s 90 one thing. I observed from the Twitter course, that it may additionally do pretty nicely. I used to be nonetheless tremendous shocked with how nicely it did as a result of I knew that individuals would really like it in the event that they performed it, and I knew that largely from my earlier procedural toy tasks, however I didn’t know if individuals would really be prepared to pay cash for it as a result of it’s form of my concept of willingness to pay is form of based mostly on I believe it’s a defective concept, however it was based mostly on the concept that individuals have a tough time spending cash for issues we are able to’t actually categorize as a result of they think about they’ve a finances for recreation issues and so they think about they’ve a finances for like meals or lease or no matter. After which when one thing comes up, this like, do I pay for this? I assumed this type of factor was imagined to be free or no matter. Folks don’t actually, like, really feel reluctant to pay for it. However I’m fairly shocked with how massive issues individuals would construct.

So the best way I got here up with just like the preliminary most grid measurement is I constructed the most important issues I ever wished to construct. After which I doubled that, however like instantly after I launched the sport, individuals had been like, oh, we want an even bigger grid. After which I did ship an replace which made the grids just a little bit greater.

However yeah, I’m fairly shocked how and there are some individuals who simply construct factor after factor after factor after factor, like large elaborate constructions and like multiples of them. So I imply, yeah, I’m undoubtedly shocked by that. I knew individuals would really like it. I assumed most individuals would play it for like one hour. No, not even actually an hour, like 40 minutes or one thing like that.

And that’s additionally why it’s so low cost. Like, the worth tag is actually low. And that’s partly as a result of I form of, I anticipated individuals to not play for that lengthy, and I didn’t need them to really feel cheated. I wished them to really feel like I performed this for an hour. and it was the worth of , a cup of espresso. So it’s alright. I imply it’s bit greater than a cup of espresso. No, it’s about. Yeah, yeah.”

Oskar Stalberg


On the time of writing, Oskar is engaged on one other challenge, and when you’re following him on Twitter, you’ll little doubt have seen some latest progress. As mentioned in a chat on the 2021 Sweden Sport Convention, Stalberg went again to the grid concept as soon as once more. Searching for to stability between utilizing each triangular and sq. tiles and tackling concepts that might not be achieved in Townscaper or Dangerous North, with cliffs and rivers being generated as soon as once more inside a hard and fast pre-defined area. It’s all received some time to go, however when you’re following Stalberg on Twitter – you’ll catch all of the updates as they occur.

Thanks for studying this text on Townscaper. It’s a recreation that has dominated a number of gamedev Twitter feeds for the previous couple of years, and with good motive. Whereas it’s now out there on just about any machine price having, you can too play a restricted demo in your net browser. Plus when you’re thinking about creating your personal procedural algorithms, hyperlinks to some supporting supplies on Marching Cubes and Wave Perform Collapse are included under, together with a implausible tutorial by Joseph Parker over on PROCJAM.

A particular thanks to Townscaper creator Oskar Stalberg for taking the time to take a seat down with me and answering the various questions I had. Particularly on condition that I requested some very particular questions on his profession thus far and the inside workings of the algorithms which were constructed. I hope this has completed his work justice!

Hyperlinks & References

  • Particular because of Oskar Stalberg for showing on this episode, you may observe him on Twitter at:
  • You may play the Townscaper PC demo at:
  • Along with our interview, this piece is impressed by the next shows:
  • Plus when you’re thinking about attempting your hand at Marching Cubes, Wave Perform Collapse or Quadrilateral Grids, then listed here are some additional hyperlinks to take a look at!