Custom Buckets

This page explains how to add custom bucket support for various in-game behaviors like milking, filling, emptying, and dispenser usage.

Note

• For cauldron interactions, see the CauldronInteraction class.
• To allow custom water buckets to pick up entities (like axolotls or fish), you must implement this behavior yourself.

Milking Cows and Goats

To allow milking with a custom bucket:

• Add your empty bucket item to the buckets/empty item tag
• Add a key-value pair (empty bucket → milk bucket) to the BUCKET_TO_MILK_BUCKET map

Emptying Buckets

The logic for emptying filled buckets checks if the item is present in the FILLED_BUCKET_TO_EMPTY_BUCKET map and returns the corresponding empty bucket.

To support this with a custom bucket, add your filled bucket to the FILLED_BUCKET_TO_EMPTY_BUCKET map.

Filling Buckets

The logic for filling buckets with vanilla fluids and powder snow checks the corresponding maps.

You can extend the following maps:

• EMPTY_BUCKET_TO_WATER_BUCKET
• EMPTY_BUCKET_TO_LAVA_BUCKET
• EMPTY_BUCKET_TO_POWDER_SNOW_BUCKET

Adding Dispenser Behaviour

For dispenser support, you need to register dispenser behaviors manually.
Refer to Minecraft's DispenseItemBehavior interface for implementation details.

To enable filling custom empty buckets via dispensers, you can use the nemosTags$pickupBlock method.
Simply cast the liquid or powder snow block to CustomBucketPickup to access it.

Example:

if (blockstate.getBlock() instanceof CustomBucketPickup bucketpickup) {
    ItemStack itemstack = bucketpickup.pickupBlock(customEmptyBucket, levelAccessor, blockpos, blockstate);
// Handle the resulting item stack (see vanilla bucket behavior for reference)
}