Crate valence

❗ NOTE: This documentation is sourced from the main branch. If you’re looking for the most recent stable release, go here.

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A Rust framework for building Minecraft: Java Edition servers.

Built on top of Bevy ECS, Valence is an effort to create a Minecraft compatible server completely from scratch in Rust. You can think of Valence as a game engine for Minecraft servers. It doesn’t do much by default, but by writing game logic yourself and leveraging Bevy’s powerful plugin system, you can make almost anything.

Opinionated features like dynamic scripting, dedicated executables, and vanilla game mechanics are all expected to be built as optional plugins. This level of modularity is desirable for those looking to build highly custom experiences in Minecraft such as minigame servers.

⚠️ Valence is still early in development with many features unimplemented or incomplete. Expect to encounter bugs, limitations, and breaking changes.

Goals

Valence aims to be the following:

• Complete. Abstractions for the full breadth of the Minecraft protocol.
• Flexible. Can easily extend Valence from within user code. Direct access to the Minecraft protocol is provided.
• Modular. Pick and choose the components you need.
• Intuitive. An API that is easy to use and difficult to misuse. Extensive documentation and examples are important.
• Efficient. Optimal use of system resources with multiple CPU cores in mind. Valence uses very little memory and can support thousands of players at the same time without lag (assuming you have the bandwidth).
• Up to date. Targets the most recent stable version of Minecraft. Support for multiple versions at once is not planned. However, you can use a proxy with ViaBackwards to achieve backwards compatibility with older clients.

Current Status

Here are some noteworthy achievements:

• valence_nbt: A speedy new library for Minecraft’s Named Binary Tag (NBT) format.
• Authentication, encryption, and compression
• Block states
• Chunks
• Entities and metadata
• Bounding volume hierarchy for fast spatial entity queries
• Player list and player skins
• Dimensions, biomes, and worlds
• JSON Text API
• A Fabric mod for extracting data from the game into JSON files. These files are processed by a build script to generate Rust code for the project. The JSON files can be used in other projects as well.
• Inventories
• Items
• Particles
• Anvil file format (read only)
• Proxy support (Velocity, Bungeecord and Waterfall)

Here is a short video showing the examples and some of Valence’s capabilities.

Getting Started

Running the Examples

After cloning the repository, run this command to try an example.

cargo r -r --example parkour

I also recommend giving game_of_life, terrain, and cow_sphere a try.

Next, open your Minecraft client and connect to the address localhost. If all goes well you should be playing on the server.

Adding Valence as a Dependency

Valence is published to crates.io. Run cargo add valence to add it to your project.

However, the crates.io version is likely outdated. To use the most recent development version, add Valence as a git dependency.

[dependencies]
valence = { git = "https://github.com/valence-rs/valence" }

Documentation from the main branch is available here.

Contributing

Contributions are welcome! Please see CONTRIBUTING.md. You can join Discord or GitHub Discussions to discuss the project and ask questions.

License

Code is licensed under MIT while the Valence logo is under CC BY-NC-ND 4.0

Funding

If you would like to contribute financially, consider sponsoring me (rj00a) on GitHub or Patreon.

I would love to continue working on Valence and your support would help me do that. Thanks!

Re-exports

• pub use bevy_log as log;
• pub use valence_advancement as advancement;
• pub use valence_anvil as anvil;
• pub use valence_boss_bar as boss_bar;
• pub use valence_command as command;
• pub use valence_command_macros as command_macros;
• pub use valence_equipment as equipment;
• pub use valence_inventory as inventory;
• pub use valence_lang as lang;
• pub use valence_network as network;
• pub use valence_player_list as player_list;
• pub use valence_scoreboard as scoreboard;
• pub use valence_weather as weather;
• pub use valence_world_border as world_border;

Modules

• abilities
• action
• app
  This crate is about everything concerning the highest-level, application layer of a Bevy app.
• block
• brand
• client
• client_command
• client_settings
• custom_payload
• ecs
  Bevy ECS
• entity
  valence_entity
• event_loop
• hand_swing
• ident
  valence_ident
• interact_block
• interact_entity
• interact_item
• item
• keepalive
• layer
  Defines chunk layers and entity layers. Chunk layers contain the chunks and dimension data of a world, while entity layers contain all the Minecraft entities.
• math
  valence_math
• message
• movement
• nbt
  Crates
• op_level
• prelude
  Contains the most frequently used items in Valence projects.
• protocol
  valence_protocol
• rand
  Utilities for random number generation
• registry
  valence_registry
• resource_pack
• spawn
  Handles spawning and respawning the client.
• status
• status_effect
• status_effects
• teleport
• testing
• text
  valence_text
• title
• uuid
  Generate and parse universally unique identifiers (UUIDs).

Macros

• ident
  Creates a new Ident at compile time from a string literal. A compile error is raised if the string is not a valid resource identifier.

Structs

• BiomePos
• BlockPos
  Represents an absolute block position in world space.
• BlockState
  Represents the state of a block. This does not include block entity data such as the text on a sign, the design on a banner, or the content of a spawner.
• ChunkLayer
  A Component containing the chunks and dimension information of a Minecraft world.
• ChunkPos
  The X and Z position of a chunk.
• ChunkView
  Represents the set of all chunk positions that a client can see, defined by a center chunk position pos and view distance dist.
• CompressionThreshold
  How large a packet should be before it is compressed by the packet encoder.
• DefaultPlugins
  This plugin group will add all the default plugins for a Valence application.
• Despawned
  A marker Component for entities that should be despawned at the end of the tick.
• EntityLayer
  A Component containing Minecraft entities.
• EventLoopPostUpdate
• EventLoopPreUpdate
• EventLoopUpdate
• Ident
  A wrapper around a string type S which guarantees the wrapped string is a valid resource identifier.
• ItemStack
  A stack of items in an inventory.
• LayerBundle
  Convenience Bundle for spawning a layer entity with both ChunkLayer and EntityLayer components.
• Server
  Contains global server state accessible as a Resource.
• ServerPlugin
• ServerSettings
• Text
  Represents formatted text in Minecraft’s JSON text format.
• UniqueId
  The universally unique identifier of an entity. Component wrapper for a Uuid.

Enums

• Difficulty
• Direction
• GameMode
• Hand
• ItemKind
  Represents an item from the game

Constants

• DEFAULT_TPS
  Minecraft’s standard ticks per second (TPS).
• MINECRAFT_VERSION
  The stringified name of the Minecraft version this library currently targets.
• PROTOCOL_VERSION
  The Minecraft protocol version this library currently targets.

Traits

• Layer
  Common functionality for layers. Notable implementors are ChunkLayer and EntityLayer.