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BlockEntityStateManager

object BlockEntityStateManager

Server-side manager for tracking and syncing block entity state to clients.

This manager:

  • Maintains a registry of block entities by position

  • Tracks which properties have changed on each block entity

  • Sends state packets to players who are observing each block entity

  • Cleans up state when block entities are unloaded

Functions

addTrackedPlayer

fun addTrackedPlayer(blockEntity: BlockEntity, player: ServerPlayer)

Adds a player to the tracking list for a block entity.

The player will receive state packets when the block entity changes.

Parameters

  • blockEntity: The block entity.

  • player: The player to add.

clear

fun clear()

Clears all tracking data.

Useful for cleanup on server shutdown.

getContainer

fun getContainer(blockEntity: BlockEntity): BlockEntityStateContainer?

Gets the state container for a block entity, if it exists.

Return

The state container, or null if not registered.

Parameters

  • blockEntity: The block entity.

hasTrackedPlayers

fun hasTrackedPlayers(blockEntity: BlockEntity): Boolean

Whether anyone is still tracking blockEntity - see unregisterBlockEntity's own caveat.

init

fun init()

Registers the server tick listener that drives syncDirtyEntities every tick.

Must be called once during mod init.

registerBlockEntity

fun registerBlockEntity(blockEntity: BlockEntity): BlockEntityStateContainer

Registers a block entity for state tracking.

Should be called when a container menu is opened for a block entity.

Return

The state container for this block entity.

Parameters

  • blockEntity: The block entity to track.

removeTrackedPlayer

fun removeTrackedPlayer(blockEntity: BlockEntity, player: ServerPlayer)

Removes a player from the tracking list for a block entity.

Parameters

  • blockEntity: The block entity.

  • player: The player to remove.

syncDirtyEntities

fun syncDirtyEntities(currentTick: Long, networkChannel: (BlockEntityStatePacket, List<ServerPlayer>) -> Unit = DEFAULT_NETWORK_SENDER)

Syncs all dirty block entities to their tracked players.

Should be called once per server tick via a tick event.

Parameters

  • currentTick: The current server tick.

  • networkChannel: The network channel to send packets through.

unregisterBlockEntity

fun unregisterBlockEntity(blockEntity: BlockEntity)

Unregisters a block entity from state tracking.

Should be called when a container menu is closed.

Parameters

  • blockEntity: The block entity to untrack.