How Minecraft Generates Worlds

It’s estimated that 2.8 trillion unique worlds are possible with Minecraft’s world generator. The worlds are essentially endless, and every game generates a completely different world map. But how does Minecraft generate these incredible worlds?

If you would like to know the answer, you’ve come to the right place. This article will explain how to generate worlds in Minecraft.

It Starts With a Seed

Minecraft world generation isn’t truly random, because every world generated starts with a seed number. When you create a world, you have the option to enter a seed or to let Minecraft choose a seed for you. These numbers are put into a “pseudorandom number generator.” This is an algorithm that generates lists of numbers that approximate random numbers.

These pseudo-random numbers are the basis of Minecraft world generation. They’re used to compute numbers for a process called “procedural generation.” This process creates data algorithmically to make textures and large-scale 3D computer graphics. This is for the case with many computer games, including Minecraft.

In summary:

• A seed number is entered.
• This seed is input into a pseudorandom number generator.
• Mathematical data is created from the seed to be used as coordinates and locations.
• Since all data comes from the seed number, an identical seed will produce an identical world.

Procedural Generation of Minecraft Worlds

As you might’ve guessed, procedural generation of the world terrain and elements follows a specific set of steps or procedures. Each step contributes to the fully developed Minecraft worlds that entertain players so well. This process is specifically based on “Perlin noise” calculations.

For Minecraft, the process has four main steps.

• Noise Maps
• Terrain Elements
• Caves and Ores
• World Decorations

Noise Maps

It’s common for computer game creation to begin with a “noise map,” and Minecraft is no exception. The first step to creating the world is the generation of a terrain noise map, which is basically a representation of the terrain in dots and shades that will later be fully developed. This terrain noise generator makes a topographic map out of stone and water.

As it generates, it begins with an Island Biome stack and follows through the rest of the biomes, adding details accordingly. The topography of each Biome is still pseudo-randomly generated, but appropriate to each biome.

Next, other noise maps are placed on top of the first one to smooth the terrain over and add biome details. If you watch closely, you’ll witness this process as your world generates. The result is a complete topography made from stone, water, and air. Minecraft generates 16×16 chunks as you explore.

Here are some more essential facts about a noise map:

• Topography is built from sone using a noise map.
• Everything below y=63 isn’t stone but water.
• Everything else is air, with the rule that air is always above water.
• Topography is expanded and smoothed based on varying biomes.
• No caves exist in the stone topography yet.

This gives the basic world that is ready to be enhanced by the rest of the creative process. At this point, the only materials used are stone, water, and air.

Terrain Elements

The next step in the progression is the addition of blocks such as grass, dirt, and sand. These aren’t built on top of the stone, but rather they overwrite the already existing stone landscape. These continue to be placed “pseudo-randomly” based on the numbers generated by the seed and building algorithm.

• Grass, sand, dirt, etc. replace stone in the topography.
• No caves are yet created.
• Ores don’t yet exist.
• Decorations on the land’s surface have not been generated yet.

Microsoft’s algorithm takes into account that the desert will need more sand, the oceans more gravel, and so on. Each biome is filled with the appropriate land material combinations.

Caves and Ores

Now that we have a world built out of stone, dirt, and suchlike, it’s time to add caves to the mountains and ravines to the valleys. This is a two-step process:

• Caves and ravines generate.
• Ores are immediately created within the stone elements.

This is when copper, coal, gold, etc. are added to the world. These are governed by Minecraft rules and distributions that are set in each version.

World Decorations

The final capstone to complete world generation is the addition of decorations to the world. This includes anything else that a world can contain. Structures populate first, followed by flora and fauna.

• Trees and foliage
• Tall grass and flowers
• Beehives, bees, and other insects
• Villages
• Shipwrecks and strongholds
• Jungle temples and desert pyramids
• Nether gates

These details vary in each world and add to the wonderful variety in Minecraft. Each item will spawn based on its particular distribution rules. For instance, some worlds can be filled with ocean and shipwrecks while others have oceans few and far between. Every world is different.

How Do Biomes Factor in?

When the initial terrain noise map is made, it is based on biome rules from Minecraft. The numbers for determining the biome areas also come from the algorithm processing the seed number. As with everything in the world, the seed number dictates how the numbers fall.

Pseudo-random temperature numbers are assigned to all areas, and these determine what biome will develop in any given region. Other fine-tuning processes run, such as blending edges of biomes together. Generation details such as these are part of Microsoft’s proprietary algorithm.

FAQ

What about the Far Lands?

The Far Lands were created when the generation algorithm got so overwhelmed that it stopped working. Users estimate that this happened at about 12 million blocks from the spawn point in any direction. Many players have set out to try to find the Far Lands. Rumor has it that the Far Lands disappeared with later updates and a whole new terrain generator.

How do Ore distributions work?

For each version of Minecraft, you can find detailed ore distributions online. These govern the spawn locations and frequency of each ore based on height or y value. For example, in version 1.20 coal can spawn from y=0 to y=320 and is most common in layers 44, 95, and 136. Looking these up can help expedite your search for precious ores and materials.

Why will a seed generate the same world every time?

Why will a seed generate the same world every time?

Minecraft Generated Worlds

The generation of such infinite gaming worlds is fascinating. Any seed number will generate its own unique world but only with that specific input. The complicated nature of the algorithm accounts for the unlimited playability of the game. In fact, each world is so big, it would be impossible to completely explore and fill any one world, much less multiple worlds. Some of Minecraft’s worlds are specifically built for a seed that has numerical meaning. As you experiment, you may find some creatively hidden world-seed correlations.

What do you think about Minecraft-generated worlds? Do you enjoy the variety they offer? Tell us in the comments section below.