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Worldgen Devtools project artwork

Modrinth · Minecraft mod

Worldgen Devtools

A mod that aids in the development of world generation data packs and mods. Allows reloading worldgen data packs in-game and resetting chunks. Colors jigsaw blocks by name and target.

Choose a version Pick your version below, then grab the matching file.

Quick answer

Which Worldgen Devtools release matches 25w15a?

Updated last month
Best match for your filters 1.3.1+25w15a
Game version 25w15a, 25w16a
Loader Fabric

Worldgen Devtools 1.3.1+25w15a targets 25w15a, 25w16a with Fabric. Installation on the client is optional. Installation on the dedicated server is optional. 1 required mod needs a matching file.

Where it goes

Is Worldgen Devtools required on the client, server, or both?

Installation on the client is optional. Installation on the dedicated server is optional.

Client Optional
Dedicated server Optional
Loader for this release Fabric
Required install it here Optional supported, not mandatory Not supported do not install here Source doesn’t say do not assume

The source marks this as usable on both the client and server.

What else does Worldgen Devtools 1.3.1+25w15a need?

1.3.1+25w15a on 25w15a. Every mod below is checked against that same setup.

1 required mod needs a matching file

Install Fabric API first, but 1 required mod has no matching file for this setup. Do not mix loader builds to force a match.

Fabric API Needed by Worldgen Devtools 1.3.1+25w15a
required
No matching file

We only count dependency files that match this setup. A file for another loader does not fill the gap.

Before you install it

Add Worldgen Devtools without breaking your instance.

Built for Worldgen Devtools 1.3.1+25w15a on 25w15a. Pick another file and the loader, install side or required mods may change.

  1. 01

    Stick to this file

    Use 1.3.1+25w15a. It targets 25w15a, 25w16a with Fabric; another release may have different loader, side or dependency requirements.

  2. 02

    Bring the mods it needs

    Install Fabric API first, but 1 required mod has no matching file for this setup. Do not mix loader builds to force a match.

  3. 03

    Put it on the correct side

    Installation on the client is optional. Installation on the dedicated server is optional.

  4. 04

    Pick the file you checked

    Use the “Get this file” button beside 1.3.1+25w15a. It opens that exact file at the source.

About this project

What does Worldgen Devtools add?

Worldgen Devtools

This is a mod that provides tools simlifying the creation of worldgen datapacks and mods.

Registry (worldgen) Reloading

Needs be enabled per world using the reloadRegistries gamerule.

Warning: While this should be fairly stable, this tool can probably still corrupt your worlds. So only enable in testing worlds

Allows the reloading of registry content (such as all worldgen data) using the /reload command, or when enabling or
disabling a datapack using the /datapack command. Without this mod, the world needs to be reopened for changes to take
effect.

Entries are never removed from registries, even when no longer present in the loaded datapacks. Instead, they are marked as
outdated, so that they don't have an effect on world generation and can't be referenced from other datapack files.
Existing chunks can still use the outdated entries though, until the world is reopened. The world-height and noise shape
(i.e. height and cell size) can't be reloaded.

Client Syncronization

Some reloaded data affects the client, such sa biome colors, dimension types, and armor trims. In multiplayer, dimension
and biome effects need to be synconized. This causes the client to redraw all chunks. If this behaviour is undesireble,
it can be disabled using the syncAfterRegistryReload gamerule.

Reset Chunks

Resetting chunks to NOISE_ONLY

The /resetchunks [<range>] command resets the chunks surrounding the player in the specified range - regenerating it with the current worldgen data and settings. Defaults to 0 (i.e. only the current chunk). If you want to reset a structure, you need to reset the chunk of the structure start.

Note: This implementation actually used the normal worldgen thread, and thus has much better performance than the unregistered vanilla command.

Colored Jigsaw Blocks

Colored jigsaw blocks in a trial chamber

Colors Jigsaw blocks based on their specified "Name" or "Target Name". If a "Name" other than minecraft:empty is set,
the jigsaw block is colored based on the hash of the "Name". Otherwise, if a "Target Name" other than minecraft:empty
is set, the jigsaw block is colored based on the hash of the "Target Name".

If both "Name" and "Target Name" are set to minecraft:empty the jigsaw block is rendered deactivated, with grayed
out arrows and connectors.

In the inventory, if a jigsaw block has stored NBT (Shift+Pick), then it is rendered with the associated color and a
tooltip indicated the "Name", "Target Pool", and "Target Name".

Get Density Command

Command to debug the values of density functions are any position.

/getDensity density_function <df> [<pos>]

Returns the value of the density function df at the specified postion (or the position of the player)

/getDensity noise_router <entry> [<pos>]

Returns the value of the density function specified in the given entry of the noise router of the current dimension at
the specified postion (or the position of the player)

Profiling of Worldgen Performance

Chunk profiling example

The time it took to generate each step of each chunk is recorded and saved in each chunk. To access it, use
the /chunkprofiling <range> command. Range controlls the amount of chunks to average the performance over; defaults
to 0.

Locate Feature

Locating huge red mushrooms

Use /locate feature <configured_feature> to locate a configured feature nearby. If the current chunk contains the feature
multiple times, it will list the up to 5 closest positions. This only works if the chunk is generated while this mod is
installed.

Logging improvements

  • Empty height ranges in placed features also log the placed feature that causes the problem.

Chase

The /chase command provides options to syncronize of the player positions between two different instances of Minecraft. Usefull for
comparing differences in worldgen. This is a vanilla command, simply registered by this mod.

Gamerules

Gamerules added by this mod:

Gamerule
maxChunkStatus Which steps of world generation should be done?
-> NOISE_ONLY: Generates stone, air, water and lava only.
-> SURFACE: Applies the surface rules.
-> SURFACE_AND_CARVERS: Applies surface rules, and carvers.
-> ALL: Applies surface rules, carvers, and features.
applyProcessorLists Should processor lists of structures be applied?
applyGravityProcessor Should terrain matching structure pieces match the terrain?
keepJigsaws Should the jigsaw blocks be kept after structure generation?
reloadRegistries Should the /reload command also reload registries?
syncAfterRegistryReload Should all clients be resend the registry content after reloading?
saveChunks Should chunks be saves? Old chunks are not deleted when disabling.

Project description from Modrinth.

Pick your setup

Worldgen Devtools by Minecraft version and loader

Choose the version and loader you play, then open the matching release.

74 available setups

Showing the newest 12 of 74 game versions. Older files are in the list below.

Check the dependencies, then try the file in a copied instance before changing a world you care about.

Recent files

Worldgen Devtools versions and loaders

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Looking for an older file? The official Modrinth project page is in Resources.