TileEntities

TileEntities are like simplified Entities that are bound to a Block. They are used to store dynamic data, execute tick based tasks, and dynamic rendering. Some examples from vanilla Minecraft would be handling of inventories on chests, smelting logic on furnaces, or area effects on beacons. More advanced examples exist in mods, such as quarries, sorting machines, pipes, and displays.

Registering

Tile Entities are created and removed dynamically and as such are not registry objects on their own.

In order to create a TileEntity, you need to extend the TileEntity class. As such, another object is registered instead to easily create and refer to the type of the dynamic object. For a TileEntity, these are known as TileEntityTypes.

A TileEntityType can be registered like any other registry object. To construct a TileEntityType, its builder form can be used via TileEntityType$Builder#of. This takes in two arguments: a factory representing some supplied method to create a new instance of the associated TileEntity, and a varargs of validBlocks which this TileEntity can be attached to. Building the TileEntityType is done by calling TileEntityType$Builder#build. This takes in a Type which represents the type-safe reference used to refer to this registry object in a DataFixer. Since DataFixers are an optional system to use for mods, this can be passed as null.

// For some DeferredRegister<TileEntityType<?>> REGISTER
public static final RegistryObject<TileEntityType<MyTE>> MY_TE = REGISTER.register("myte", () -> TileEntityType.Builder.of(factory, validBlocks).build(null));

Creating a TileEntity

To create a TileEntity and attach it to a Block, two methods must be overridden within the Block subclass:

IForgeBlock#hasTileEntity(BlockState state)

IForgeBlock#createTileEntity(BlockState state, IBlockReader world)

Storing Data within your TileEntity

In order to save data, override the following two methods:

TileEntity#save(CompoundNBT nbt)

TileEntity#load(BlockState state, CompoundNBT nbt)

Ticking TileEntities

If you need a ticking TileEntity, for example to keep track of the progress during a smelting process, you need to add the net.minecraft.tileentity.ITickableTileEntity interface to your TileEntity. Now you can implement all your calculations within ITickableTileEntity#tick.

Synchronizing the Data to the Client

There are three ways of syncing data to the client: synchronizing on chunk load, on block updates, and with a custom network message.

Synchronizing on Chunk Load

For this you need to override

TileEntity#getUpdateTag()

IForgeTileEntity#handleUpdateTag(BlockState state, CompoundNBT nbt)

Synchronizing on Block Update

This method is a bit more complicated, but again you just need to override two methods. Here is a tiny example implementation of it:

@Override
public SUpdateTileEntityPacket getUpdatePacket(){
    CompoundNBT nbtTag = new CompoundNBT();
    //Write your data into the nbtTag
    return new SUpdateTileEntityPacket(getBlockPos(), -1, nbtTag);
}

@Override
public void onDataPacket(NetworkManager net, SUpdateTileEntityPacket pkt){
    CompoundNBT tag = pkt.getTag();
    //Handle your Data
}

• The position of your TileEntity.
• An ID, though it isn’t really used besides by Vanilla; therefore, you can just put a -1 in there.
• An CompoundNBT which should contain your data.

Now, to send the packet, an update notification must be given on the server.

World#sendBlockUpdated(BlockPos pos, BlockState oldState, BlockState newState, int flags)

Synchronizing Using a Custom Network Message

This way of synchronizing is probably the most complicated but is usually the most optimized, as you can make sure that only the data you need to be synchronized is actually synchronized. You should first check out the Networking section and especially SimpleImpl before attempting this. Once you’ve created your custom network message, you can send it to all users that have the TileEntity loaded with SimpleChannel#send(PacketDistributor$PacketTarget, MSG).