Procedural Generation

Procedural generation is a form of creating media automatically. Rather than hand-crafting every coastline, mountain, tree, person and their identity, a designer makes a system where they need to enter a few variables and the program works up the details. It's a bit of a double-edged sword: when it's done well, it works really well, but when it's done poorly, it can just look like a mess.

Procedural generation has a kind of sinusoidal history: it was pretty much required in the days of 8-bit gaming, as cartridges and computers literally did not have enough memory to generate all the levels. This brought in the concept of using "seeds" to grow a randomly generated world which looked realistic and challenging. Then, as games got more detailed and had more capacity, level generation was done manually, as by this time, random generation, particularly in games with save features, took up more space than static levels (take Dwarf Fortress for example: each world can hit 100MB... in .txt form) As of late, procedural generation in video games tends to be behind the scenes: in AI, for example, or for audio or visual effects.

Even if static maps exist in a game, it's possible procedural generation was used in development to save map developers some time... and is probably most likely if it involves random tree or rock placement, or anything to do with cliffs or coastlines.

The Demoscene has historically made more use of these techniques than anybody, in order to eke out spectacular graphical effects from tiny, tiny packages.

Randomly Generated Levels, Randomly Generated Loot and Dynamic Difficulty (and, by extension, Rubber Band AI) are subtropes; put pure examples of either there.


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     Video Games  

  • Demoscene competitions challenge developers to make the most advanced 4K, 1K, 256 byte, 64 byte or even 32 byte software.
  • Spore can take any creature design and make it workable. And that's not including the amount of stars in the galaxy and the planets surrounding those stars and the creatures on those planets, all procedurally generated.
  • Portal 2 procedurally generates music based on user actions, using a decent number of different sound effects. The game composer mentions that the frequency of hearing the same track twice is somewhere in the tens of thousands of years.
  • Left 4 Dead handles music the same way, giving each survivor their own music based on what was happening to and around them, and not necessarily to his teammates. Additionally, spectating a player will also duplicate that player's music for the spectator.
  • There's a trend in Rhythm Games to do this: creating maps from a user's music collection. Dance Factory most likely started this, making Dance Dance Revolution-style step charts, and indie games like Audiosurf and 1...2...3...Kick It! (Drop That Beat Like An Ugly Baby) offer different takes on the idea.
  • .kkrieger was very famous in its day for being an FPS built near-entirely on procedurally generated content, matching the likes of Doom 3 with a filesize of only 96 kilobytes.
  • Conway's Game Of Life is an artificial life simulation which involves drawing cells on a grid and then applying the game's rules to them. It can lead to some surprisingly life-like patterns. The Other Wiki has some particularly awesome animations.
  • Elite was one of the first games to use this technique to generate not only worlds, but names, descriptions, and even prices of commodities, among many other innovations, by using the Fibonacci sequence. All in 22 kilobytes - your phone likely uses more for menu transitions.
  • Borderlands does this for your loot. It was going to make the world this way as well.
  • cactus' several games, including Protoganda games and Burn The Trash use random seed generator to create enemies out of random parts that are always the same. These games also often included "random" option where enemies are completely random.
  • The Elder Scrolls
    • Arena and Daggerfall were almost entirely generated in this fashion, with a few plot-specific cities and dungeons as exceptions. The former being the size of Europe, the latter being only the size of Britain or so.
    • Morrowind went away from it for the first and, to date, only time in the main series. The entire world was hand-created and remains exactly the same between play throughs.
    • Almost all of Oblivion is created through simulated soil erosion, with dungeons being made of random parts of quest dungeons, making for long, repetitive crawls. Coupled with enemy and loot spawns being spread sheet generated, much of the uniqueness seen in Morrowind was lost.
    • Skyrim, while still having non-quest related areas of the landscape generated in this fashion, made a move away from this trope compared to Oblivion. Even many non-quest related areas were still hand built to inspire awe and give the game's regions a more unique feel.
  • Fuel is a Racing Game with a map of 14,000 square km of postapocalyptic wilderness, or half the size of Belgium. It uses a fixed seed generated by the developers and a few manually created landmarks.
  • Minecraft procedurally generates landscapes that are, for all practical purposes, infinite. There's an end, but it's about 30,000 kilometersnote  from your spawn point, which would take a minimum of 820 hours of gameplay to reach without cheating. The terrain randomly contains NPC villages, dungeons, strongholds, temples, and abandoned mineshafts, as well as thirty six distinct biomes, including mountains, jungles, deserts, swamps, and tundras. This combines to create an immense worldnote  that you could spend your entire life exploring, if you felt like it. Furthermore, the game uses a special code called a seed to keep generated terrain consistent, and there are roughly four billion seeds to choose from, each of which can generate a unique world. The same seed can be used to generate the same world on any computer, and there are quite a few websites dedicated to sharing interesting seeds with other players. The alternate dimensions, the Nether and the End, also generate procedurally, which results in extremely varying layouts in different seeds for both as they consist basically of massive cliffs and floating islands respectively.
    • Cube World shares a similar system where the world generates as you progress, which can contain different biomes, cities, and dungeons. The worlds use seeds as well, so players can share interesting maps with each other.
  • Dwarf Fortress takes the above example Up to Eleven; not only does it generate terrain for a region up to the approximate size of the planet Earth, it also simulates weather, erosion and other geographical features in minute detail. And then it adds up to a thousand years of procedurally generated history: Wars, battles, the rise and fall of empires and dynasties and even the creation of great works of art and literature.
    • The game even has procedurally generated "forgotten beasts" living underground, similar "titans" living above ground, various "night creatures" generated from a different format, and the procedurally generated Hidden Fun Stuff. The .40 versions also contain procedurally generated metal, weapon, armour, and entity raws for adventure mode HFS.
  • Noctis: A space flight simulator allowing you free roaming in a galaxy approximately 90 thousand light-years in radius (about double the radius of the Milky Way Galaxy) made of over 78 billion stars, many with planets and moons. If you pick any point in the starfield, you can go there, then land on any rocky planet you find and roam around, created by a program of under a megabyte.
  • Cloudberry Kingdom is a Platform Game that generates its levels based on the player's skill level and the type of power (Double Jump, Flight, Jet Pack, etc.) they are using. Even at its most sadistic, most levels are designed to be solvable.
  • Kingdom of Loathing has a number of zones based around randomly-generated content, such as the GameInformPowerDailyPro dungeon. It's even possible to use a psychoanalytic jar on game creator Jick and try and fight your way to the top of the Tower of Procedurally-Generated Skeletons.
  • No Man's Sky, a sort of Spiritual Successor to Noctis: A space flight simulator allowing you free roaming in a massive universe full of stars, all of which support at least one of the game's 18 quintillion planets, all procuedurally-generated. And the planets aren't the only things that are procedurally-generated, either: every plant, animal, asteroid field, spaceship, trading route, weapon, and space station in the game is also procedurally-generated.
  • XCOM 2 features procedurally-generated maps that used pregenerated UFO and building elements as part of the landscape.
  • Spelunky uses PRNG level 'chunks' that are then ever-so-slightly further randomized.
  • One Way Heroics uses seeded PRNG worlds. You can share these worlds by providing the seed numbers to other players.
  • The "Oblivion" music from Turok 2 is an apparently infinite non-looping sequence of pseudo-randomly arranged instrument clips.
  • In Westerado, the appearance of a person who killed your family in the opening, and who is searched by the player the entire game is randomly generated every time you play to keep the game fresh. Even their gender can change!
  • Gangland had the wife of Player Character Mario who gets killed later in the storyline procedurally generated.
  • The traitors in Lost Dimension are randomized each time through the game, with the sole exception of the first one. On a New Game+, that is also randomized.
  • Empire Earth: Random maps are generated according to some specifications (terrain type, map size...), but the editor allows their creation with just a seed number.

    Pen-and-Paper RP Gs 
  • Dungeons & Dragons 5E DMG includes tables of random dungeon rooms, monsters, and loot, allowing a DM to run a simple yet varied Dungeon Crawl with zero prep just by rolling some dice and engaging their imagination.
  • Dogs in the Vineyard contains a procedure for the Game Master to quickly generate entire towns from a single conflict idea.
  • Blades in the Dark has tables for randomly generating entire city parts, missions, NPCs, and even simple word on the street from a couple dice rolls. The official usage instruction of these tables simply says "Roll some dice and use the results and these tables however you see fit."


Alternative Title(s): Procedurally Generated Levels