Blog: Procedural map generation in The Riftbreaker

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The Riftbreaker is a sport this is closely influenced by means of quite a lot of genres. The bottom-building and base protection facets of the sport carry again recollections of each vintage and fashionable real-time technique video games. Looting and crafting techniques resemble the ones recognized from action-RPG titles. Dynamic climate, time of day, and exotic biomes are all precious portions of video games fascinated by exploration and survival. What connects all the ones genres is the truth that their gameplay advantages strongly from map selection. 

Our newest base-building trailer presentations off various biomes and places inside them.

The Riftbreaker’s major merit is that no two play classes are ever the similar. Although what to anticipate, the precise main points of every challenge must be found out by means of the participant each and every time they begin a brand new sport. The one means to reach that kind of selection is thru procedural map technology. This selection has all the time been some of the design pillars of The Riftbreaker and one of the crucial important duties for all of the challenge. The sport makes use of our personal engine, The Schmetterling, which additionally powered our earlier tasks, Zombie Motive force and X-Morph: Protection. Then again, the ones video games used pre-designed, fastened ranges. On this article, we will be able to inform you concerning the global technology machine that we got here up with for The Riftbreaker.

The map technology procedure is performed sooner than every new Survival Mode playthrough. The basis of this mode is for each and every consultation to be a standalone revel in, and a procedurally generated global is helping an excellent handle that. The method is divided into a few levels – let’s check out every of them.

Biome randomization

The method starts with the number of biome by means of the consumer. For the participant, the number of biome will impact the varieties of creatures they will stumble upon, the pool of to be had dynamic climate occasions, in addition to the supply of sources and the total appear and feel of the play house. For the sport itself, alternatively, the biome defines a collection of overarching parameters that can impact the sector technology procedure. Each and every biome preset in The Riftbreaker incorporates data at the lighting fixtures parameters, the skybox, and its homes, in addition to a collection of fabrics for use as the bottom textures for the terrain. Biomes additionally outline what tiles are to be had for the sport to make use of when producing the map.

Pattern number of textures for the jungle biome.

Snippets from the quite a lot of biomes avid gamers will talk over with all over the marketing campaign: jungle, wasteland, acid and magma.

Biomes do not need a ‘fastened’ configuration, which means that two ‘jungle biome’ maps can glance very other from one any other. We succeed in that due to biome randomization. As a substitute of giving the sport a collection of homes it has to make use of, we give it a pre-configured set of choices to randomize from. In consequence, it’s extremely not going that the sport will make a choice a collection of an identical fabrics, skyboxes, and lighting fixtures for any given two playthroughs. Whilst nonetheless pre-defined by means of our designers, mix and matching the biome homes introduces slightly little bit of selection into the sector technology proper from the beginning.

Tile advent

Finally the biome parameters were decided on, the set of rules starts to accomplish the primary operations at the tiles. Tiles are our fundamental constructing blocks for map technology in The Riftbreaker. They’re the smallest editable chunks that our degree designers get ready manually. Their minimal measurement is 128×128 meters (or 64×64 in-game grids. Each and every grid in our sport is a 2x2m sq.). Tiles want to meet some fundamental standards sooner than they’re in a position to be put into the sport. Then again, those necessities are simple to satisfy and they are able to be fulfilled in some inventive tactics in order that they don’t restrict the designers’ freedom. 









The dressmaker of the tile simplest has to hide the terrain with a few varieties of mask. The textures might be randomly selected from the to be had set.

One such requirement is overlaying the skin with terrain blends. The outside house can also be coated by means of one among 3 world fabrics – for simplicity’s sake let’s title them A, B, and C – those that had been decided on within the biome randomization procedure. Designers don’t make a choice the fabrics, they just designate zones that the sport will quilt the usage of subject matter set A (e.g. sandy textures), subject matter set B (e.g. grassy terrain), and subject matter set C (e.g. rocky bedding). It’s also imaginable to color a space with an actual texture as an alternative. If so, the randomization procedure won’t impact it. 

If the dressmaker chooses to make use of a typical texture as an alternative of a masks, that house might not be suffering from the randomization procedure. It is helpful for including main points underneath props.

After that, the author of the map can get started hanging spawn issues for the sport good judgment components. They come to a decision the place the participant can perhaps get started their adventure, the useful resource placement (and their selection), in addition to all of the NPCs that can fill the sport global.

Prefab randomization

Right here you’ll see precisely what house has been marked to get replaced by means of prefabs, in addition to which props were positioned robotically.

An extra component of randomness that we determined to include into the sector technology algorithms for The Riftbreaker are so-called prefabs. In our case, a prefab is a different hand made scene, that is full of quite a lot of props by means of a dressmaker. Their objective is to fill the clean areas of the map tiles left by means of designers and marked to be masked by means of prefabs. In different phrases – prefabs lie beneath the common tiles and pa up anywhere there’s a window left for them to take action, filling the world with props in a randomized means with out the desire for any further human enter.

Portray with prefab masks permits you to get a unique-looking tile very quickly.

The dressmaker chooses which of the pre-made prefab scenes they want to be used on their new tile. Each and every prefab has its personal masks, and the dressmaker comes to a decision the place they want to use it. Props from the predefined scene will then fill the masked house. When the map is being generated the positioning and orientation of the prefabs are selected at random. Then, a number of copies of the prefab scenes are stitched in combination to lie beneath all of the house of the sport global. This fashion, we will ensure that without reference to the world designated by means of the author the prefab masks will be capable of fill the world marked by means of the dressmaker with props. Slight variations in positioning, orientation, and prefab selection can vastly trade the sensation of the tile.

A number of variants of prefab scenes. They’re jam-packed with props in order that they are able to do their task without reference to the place they get situated.

This is identical map. The one factor that adjustments is the generator seed for the prefab randomization. The results of that vary from very delicate to totally unrecognizable. 

Tiled map technology

Now that the tiles were randomized it’s time to generate the map. The sport tests how large the map will have to be – we give a boost to quite a lot of map sizes, from single-tile ones to behemoths of 12×12 tiles. The present, builds of The Riftbreaker generate 5×5 maps for Survival Mode and sundry sizes for Marketing campaign mode. The dimensions of the map impacts each gameplay alternatives and engine efficiency. Exploration missions within the marketing campaign require higher playable spaces whilst base protection targets can are compatible into smaller worlds for extra streamlined gameplay.

The dressmaker will have to additionally assign data to every fringe of the a for matching functions. Tiles will simplest be hooked up to one another if their facets fit, fighting connection mistakes. The tile randomization procedure chooses which tiles are going for use for map technology, which of the spawn issues are going for use, and the way tiles are going to be turned around (we give a boost to rotations of zero, 90, 180, and 270 levels). Tiles would possibly repeat all over the map technology procedure and so they would possibly range in homes between cases. 

The sport global is generated by means of fixing a model of the ‘Wang tile downside’. You’ll be able to examine this idea right here. Within the authentic downside, the coloured facets of the tiles have to check every different with out acting any rotations. Our case is simplified slightly since we permit for rotations, alternatively, neighboring tiles nonetheless have to check every different relating to facets. It takes moderately slightly of gymnastics to make all of it paintings, however the ensuing choice of mixtures may be very prime. 

It’s imaginable so as to add extra floor house on your paintings. The sport will nonetheless deal with is as one tile, stay all of the advent in a single piece and are compatible it with different tiles all over map technology. It permits the designers to create multi-tile buildings, like mountain levels or canyons.

It’s value bringing up that no longer all tiles want to be 128×128 meter squares. We give a boost to mixtures of a number of ‘base’ tiles as smartly to give a boost to exotic buildings spanning over a number of tiles, comparable to large rock formations, huge lakes, or rivers. If a different tile construction like that is selected to be a part of the generated global it’s put at the map in its entirety to keep the continuity of the props ready by means of the designers. The encircling house is then stuffed with randomized tiles as same old.

Useful resource and Participant Spawn Level Randomization

After all, after the set of rules has generated the map thru all of the steps described above, we will transfer directly to the distribution of sources. Each and every challenge in The Riftbreaker defines what sort of sources will have to be made to be had to the participant. Then again, it simplest specifies the quantities of sources to be to be had all over the challenge, no longer their localization. This is randomized once more. The sport chooses imaginable spawn issues for useful resource deposits and distributes them in keeping with a related ruleset. 

An instance of the ruleset for useful resource distribution. All sport modes and maps require their very own rulesets to change and stability the gameplay revel in.

As soon as a useful resource spawn level is selected by means of the set of rules, the method is moderately easy. The useful resource kind is selected, adopted by means of the ‘density’ of the deposit – the quantity of sources that might be to be had for the participant to make use of. That price is a straightforward roll between the minimal and most values explained within the challenge good judgment report. Then, the sport tries to decide the middle of the useful resource deposit. The sector would be the richest in opposition to the middle, which might be represented by means of a special bodily fashion for simple visible id.

Assets can spawn within the house marked with crimson. The sport will decide the middle of the useful resource deposit, its yield, after which alter the mesh accordingly.

As soon as all of the sources were disbursed, the sport tests all of the participant spawn issues and chooses the only which is the nearest to the minimal fundamental sources essential for the participant. As soon as this kind of position is decided, the participant can in any case get started the sport. 

We’re proud of the map technology machine that we advanced for The Riftbreaker. It permits us to introduce a large number of selection to the sport global in slightly short while. Including even a few new tiles to the biome pool makes for a fascinating revel in for each new and returning avid gamers. Upload randomized prefabs giving the map tiles a quite other appear and feel each and every time, and you have got a cast basis to construct the sport on. 

The present state of the machine may be very purposeful, however it may nonetheless be progressed with quite a few helpful options to make the sport global extra life like. We’re operating on dynamic NPC placement that can adapt in keeping with the biome, the selected issue degree, time of day, in addition to the participant’s growth within the sport. With this kind of machine in position The Riftbreaker will grow to be a sport that encourages dynamic determination making and adjusting to the stipulations, moderately than finding out the precise process had to entire every challenge. 

This is all we have now for you these days. When you’ve got any questions, be happy to publish them within the remark segment or catch us at once on our Discord server: 

See you subsequent time!

EXOR Studios

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