Binding an item to an entity

[Cappy]

Hey there, I wanted to know how I can summon an entity when I right click an item and bind it to the item after summon so that the user can't use it again until the entity is dead.

Can someone help me with this?

[Luis_ST]

overwrite use in your Item class and create a new instance of the Entity you want, add it via Level#addFreshEntity
and store the UUID of the Entity in the Tag of the given ItemStack. use as Tag key your mod id + the key you want
last but not least put the whole code in a if condition where check if the ItemStack has your key and then check if the Entity is present in the Level

[Cappy]

Just now, Luis_ST said:

overwrite use in your Item class and create a new instance of the Entity you want, add it via Level#addFreshEntity
and store the UUID of the Entity in the Tag of the given ItemStack. use as Tag key your mod id + the key you want
last but not least put the whole code in a if condition where check if the ItemStack has your key and then check if the Entity is present in the Level

How do I exactly check if the entity is present in the level? All options only work for loaded chunks, what if my chunk isn't loaded?

[Cappy]

On 3/27/2022 at 1:49 PM, diesieben07 said:

Then you cannot know.

So how can I exactly keep track of an entity even though he is in an unloaded chunk? I want to summon an entity and then not let the player summon another one until the entity dies.

[Cappy]

43 minutes ago, diesieben07 said:

The only way would be to either make the entity a chunkloader (inefficient) or keep track globally (e.g. WorldSavedData or a World Capability).

Can you save entities in NBT? If you save them, You need to resummon them because of chunks, no?

[Cappy]

14 minutes ago, diesieben07 said:

You'd store the link between the two (UUID of both player and entity) in the global storage. Then when the entity dies (which it can only do if it is loaded), you remove it from global storage.

How do I listen to the death event of a vanilla entity?

[Cappy]

23 minutes ago, diesieben07 said:

LivingDeathEvent

How will I access the data in the event, I need a serverlevel and I can't get it in event.

[MFMods]

On 3/28/2022 at 11:18 PM, Cappy said:

How will I access the data in the event, I need a serverlevel and I can't get it in event.

assuming you want to use world saved data and that you want to attach it to overworld only (single save for all dimensions), it would be something like this:

entity death event:
    if client then return;
    if not enty type we are trying to handle then return
    verify saved data initialized(parameter: world from event);
    savedData.summonId = empty;
    savedData.dirty = true;

verify saved data initialized function
    if savedData not null then return; // not local
    savedData = ((ServerWorld)currentWorld).getServer().overworld().getDataStorage().computeIfAbsent(OurWorldSavedData::new, OurMod.MODID);
 

do read the manual:
https://forge.gemwire.uk/wiki/Saved_Data
https://mcforge.readthedocs.io/en/1.18.x/datastorage/saveddata/