[Forge 1.15.2] Item Filter help

[NindyBun]

My item container works fine, it acts as a normal bag; but I want to turn it into a filter, so how can I make my item container set/remove "ghost" items instead of setting/removing the physical item in a slot? Thanks in advance.

Note: I am asleep so I won't be able to answer till I wake up.

[Soft-fur dragon]

I may not understand the context, but why don't you want to store "physical" items (I guess, you were talking about ItemStack)?

Can you also explain more, what do you mean at all?

P.S. Or you mean "ghost" items like in crafting table when you click on recipe?

Edited March 22, 2021 by Soft-fur dragon

[kiou.23]

I'm pretty sure that you could override the Container#slotClick method, it handles what happens when, well, you click on a slot... the logic for it is quite obfuscated and confusing however... so there may be a better way to do it

EDIT: If I'm not mistaken, the code between lines 290 and 342 of the Container class are the ones which handles when the player is holding an ItemStack, and clicks on a slot of the container

Edited March 22, 2021 by kiou.23

[Draco18s]

I did "ghost" items once, and this is the ItemStackHandler subclass:

https://github.com/Draco18s/ReasonableRealism/blob/1.14.4/src/main/java/com/draco18s/industry/inventory/FilterStackHandler.java

Looking at it now, I think line 23 is wrong, should be return stack.copy() (or pass a copy to super and return the original).

But I haven't messed with it in a while. The extract method is correct though.

[NindyBun]

6 hours ago, Draco18s said:

I did "ghost" items once, and this is the ItemStackHandler subclass:

https://github.com/Draco18s/ReasonableRealism/blob/1.14.4/src/main/java/com/draco18s/industry/inventory/FilterStackHandler.java

Looking at it now, I think line 23 is wrong, should be return stack.copy() (or pass a copy to super and return the original).

But I haven't messed with it in a while. The extract method is correct though.

So I returned stack.copy() and I am still holding the stack, but when I try to set stack in slot, it doesn't set the ItemStack.

[NindyBun]

8 hours ago, Soft-fur dragon said:

I may not understand the context, but why don't you want to store "physical" items (I guess, you were talking about ItemStack)?

Can you also explain more, what do you mean at all?

P.S. Or you mean "ghost" items like in crafting table when you click on recipe?

Basically I want to make an Item Filter that allows the player to set a copy of the held item stack into a slot. 

[Draco18s]

Show your code. Would be best if you posted a link to a git repo.

[NindyBun]

34 minutes ago, Draco18s said:

Show your code. Would be best if you posted a link to a git repo.

https://github.com/NindyBun/TestMod/blob/master/src/main/java/com/nindybun/miningtool/test_item/ItemStackHandlerTestItem.java

[Draco18s]

Why do you have both of these lines?

Why did you change this line? I told you that method was correct. By returning what's IN the slot you allow item duplication (remember, you're trying to create ghosts! Players can't acquire ghosts!)

Why do you have this method? You (1) aren't using it and (2) you aren't using imports and (3) you can just inline it's contents anywhere you would reference it.

OrElseThrow() is a thing. So is ifPresent(), which would obliviate the need for this static method anyway.

Jesus H Christ why are you comparing strings here.

And of course the rest of that if-stack is a bunch of absolutely nonsense. You're checking if the player's held stack is equal to any of the upgrades already applied or if the held stack is Fortune or Silk Touch and that one of the existing upgrades is the other (so either (a) there's an identical upgrade applied or (b) you generate a Fortune/Silk Touch pair) then if the held stack is an upgrade (why was this not checked first?) and the held stack has the same item as the selected inventory slot's item, return true. If any of that is false, prevent insertion.

Not only are all of those checks fucking nonsense, and done out of order, but what if the slot is empty? Your method returns false if the slot is empty, preventing the slot from ever being not-empty.