Dynamic Multiblock System 1.21.1 not in 1.21.2–1.21.11 26.1

Availability

This module is available in Minecraft 1.21.1 and 26.1. Versions 1.21.2 through 1.21.11 were not synced due to development resource constraints. If you are using these versions, the dynamic multiblock feature is unavailable.

The package dev.anvilcraft.lib.v2.multiblock provides a dynamic multiblock structure system. It supports defining multiblock shapes via datapack or code, asynchronous block matching, automatic structure state tracking (formed/unformed), and network synchronization to clients.

Architecture Overview

1. Definition (MultiblockDefinition) -- Describes the blocks/predicates required at each relative position in the multiblock structure
2. Controller (IController / SimpleController) -- The "brain" of the multiblock, binding a block + definition ID and providing formed/unformed callbacks
3. State (MultiblockState) -- Runtime multiblock instance, tracking controller position, definition reference, and formed status
4. Manager (DynamicMultiblockManager) -- Per-dimension global manager, persisted as SavedData
5. Async Detection -- Independent thread pool performs predicate matching to avoid blocking the main thread
6. Network Sync -- MultiblockFormPacket / MultiblockUnformPacket synchronize state to clients

Document Index

Document	Content
Definition System	MultiblockDefinition, Builder, SeriaBuilder, serialization
Controller	IController, SimpleController, ControllerRecord
Runtime Management	DynamicMultiblockManager, MultiblockState, async detection, configuration

Module Main Class

AnvilLibMultiblock

Mod entry point, @Mod("anvillib_multiblock").

public static final String MAIN_ID = "anvillib";
public static final String MOD_ID = "anvillib_multiblock";
public static final AnvilLibMultiblockConfig CONFIG;

public static Identifier of(String path); // → anvillib:<path>

Quick Workflow

1. Create a MultiblockDefinition (Builder or SeriaBuilder)
2. Create a SimpleController subclass and register it with ControllerRecord
3. Place the definition JSON in the datapack at data/<ns>/anvillib/definitions/ (or register via code)
4. Place the controller block → the system automatically detects and triggers onFormed/onUnformed

Notes

• '0' or Vec3i.ZERO in definitions represents the controller position
• Adjust the async detection thread pool size based on the actual number of multiblocks
• MultiblockState is persisted as SavedData, surviving restarts
• State changes are automatically synchronized to all online players via IClientboundPacket