[1.14.4] Villagers Professions (Fix) & Trades

[CAS_ual_TY]

In honor of this thread, Im going to quickly summarise what I have gathered about creating villagers professions in 1.14.4 (forge 28.1.109) as there is not really that much information about that available right now. If anyone sees me doing something wrong or saying bs, just let me know and I will fix it. Specifically the reflection fix I mention below.

 

EDIT: Make sure you check the first couple replies as well.

 

Source for all of this can be found specifically in this commit: https://github.com/CAS-ual-TY/GunCus/commit/817848784868f4e8362d4270be6f8fc19863dc42 Tho I have done a few extra things which are unrelated so dont wonder.

 

PointOfInterestType

If you check out the vanilla class, you could come to the conclusion, that these are generally types of points of interest for villagers. You have the blocks in there that give the villagers their professions (eg. the Armorer type has a Blast Furnace passed to the constructor), you have a Bed type for sleeping, Unemployed type, Meeting type, etc. (But most importantly you have all the professions). You make your POITypes in the forge registry event for that (Register<PointOfInterestType>) (dont forget to set the registry name).

Constructor is: String name, Set<BlockState> blockStates, int maxFreeTickets, SoundEvent workSound, int something. Name seems to just be the lower case name (eg. "fletcher", "leatherworker" etc.), the blockStates are just all block states of the interest block. There is a helper method for this (unfortunately its private, so youll have to figure something out for yourself) which I will post below. Next you have what it seems to be the amount of villagers that can use this at once. All vanilla professions have this at 1. Next you have the work sound. I just use vanilla sounds here, so youll have to check yourself if your sound event public static final instances are populated already at this point. And finally you have another integer which I have no idea about. All vanilla professions have this at 1 too.

 

VillagerProfession

Now we create the villager profession. This is the type of profession a villager can have (eg. Flether, Weapon Smith etc.). We use the forge registry event for this again (Register<VillagerProfession>) (again, dont forget to set registry name).

Constructor: String nameIn, PointOfInterestType pointOfInterestIn, ImmutableSet<Item> noIdea, ImmutableSet<Block> noIdeaAgain. The name is the lowercase name again (eg. "fisherman", "mason" etc.). This is needed for the texture and translation (see below). Next you pass the PointOfInterestType for this profession (read above that this is). Since P comes before V, these are already registered and object holders are populated, so you can just pass your static fields here. The 2 sets that come now I havent really looked into because all vanilla professions just pass an empty set here (ImmutableSet.of()).

 

Profession Texture Location

assets\MOD_ID\textures\entity\villager\profession\PROFESSION_NAME.png

You just have to put the texture in the appropriate location. Rendering is done automatically. If you want to play around with the model a bit (eg. change the hat), check out the vanilla villagers. You can do that by adding extra PROFESSION_NAME.png.mcmeta files to the same location. Just check out vanilla for examples: assets\minecraft\textures\entity\villager\profession

 

Profession Trading GUI Title Translation

entity.minecraft.villager.MOD_ID.PROFESSION_NAME

This is the key for your .lang file. Translate this to set the title of the trading GUI. At first I was confused, because there is 2 mod ids in there (mine and minecraft). But it makes sense because the villager is part of minecraft, but the professions part of *MOD_ID*. So ye.

 

Adding Trades to Professions

Forge has 2 events for that: VillagerTradesEvent, WandererTradesEvent. You can add trades to any profession here. 1st one allows to add trades to every profession and their levels (1-5, novice to master or smth). 2nd one allows to add generic or rare trades to the wanderer. I highly suggest checking out the vanilla trades to have an idea what (or how much) to set here for all the params: https://minecraft.gamepedia.com/Trading#Armorer

- To do the first: Call event.getTrades().get(level).add(some_ITrade_instance_or_lamda_action). To do this for the profession you want, check if event.getType() == ModVillagerProfessions.YOUR_PROFESSION (this event gets called once for every profession).

- To do the second: Just check out the event class. Pretty simple. Easy getters easy life

I have made a helper class for this to allow easy trade creation. I will post it below. Example usage of this helper class (adds a trade to level 1; You can buy 2-4 (picked randomly per villager, but steady) acacia fences for 12 emeralds):

event.getTrades().get(1).add(new RandomTradeBuilder(8, 10, 0.05F).setEmeraldPrice(12).setForSale(Items.ACACIA_FENCE, 2, 4).build());

 

Final Reflection Fix

Im just going to quote what I have written on forge discord. See below for fix (in helper section, call for every POIType in your init):

Quote

So I have done some custom villager professions now, and it doesnt seem like any villager is picking up the profession, unless I invoke PointOfInterestType::func_221052_a which is a private static method. After calling that with my professions, everything worked perfectly. To make sure, I have removed this reflection call again, and it turns out that it still works, but only in villages that have already had a representative of these professions atleast once.

So without this call, the villages which had these professions already once, worked. Even when removing the villagers and/or blocks again and replacing them somewhere else (in village radius). New villages would not work at all without this call. They could only pick up other professions. Atleast this is the result I came to with some 30min+ testing

 

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Helper Stuff (use this as you please)

 

Get all Block States

   static Set<BlockState> getAllStates(Block block) {
      return ImmutableSet.copyOf(block.getStateContainer().getValidStates());
   }

 

Easy/Random Trades Builder

package here

import java.util.Random;
import java.util.function.Function;

import net.minecraft.entity.merchant.villager.VillagerTrades.ITrade;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraft.item.Items;
import net.minecraft.item.MerchantOffer;

public class RandomTradeBuilder
{
    protected Function<Random, ItemStack> price;
    protected Function<Random, ItemStack> price2;
    protected Function<Random, ItemStack> forSale;
    
    protected final int maxTrades;
    protected final int xp;
    protected final float priceMult;
    
    public RandomTradeBuilder(int maxTrades, int xp, float priceMult)
    {
        this.price = null;
        this.price2 = (random) -> ItemStack.EMPTY;
        this.forSale = null;
        this.maxTrades = maxTrades;
        this.xp = xp;
        this.priceMult = priceMult;
    }
    
    public RandomTradeBuilder setPrice(Function<Random, ItemStack> price)
    {
        this.price = price;
        return this;
    }
    
    public RandomTradeBuilder setPrice(Item item, int min, int max)
    {
        return this.setPrice(RandomTradeBuilder.createFunction(item, min, max));
    }
    
    public RandomTradeBuilder setPrice2(Function<Random, ItemStack> price2)
    {
        this.price2 = price2;
        return this;
    }
    
    public RandomTradeBuilder setPrice2(Item item, int min, int max)
    {
        return this.setPrice2(RandomTradeBuilder.createFunction(item, min, max));
    }
    
    public RandomTradeBuilder setForSale(Function<Random, ItemStack> forSale)
    {
        this.forSale = forSale;
        return this;
    }
    
    public RandomTradeBuilder setForSale(Item item, int min, int max)
    {
        return this.setForSale(RandomTradeBuilder.createFunction(item, min, max));
    }
    
    public RandomTradeBuilder setEmeraldPrice(int emeralds)
    {
        return this.setPrice((random) -> new ItemStack(Items.EMERALD, emeralds));
    }
    
    public RandomTradeBuilder setEmeraldPriceFor(int emeralds, Item item, int amt)
    {
        this.setEmeraldPrice(emeralds);
        return this.setForSale((random) -> new ItemStack(item, amt));
    }
    
    public RandomTradeBuilder setEmeraldPriceFor(int emeralds, Item item)
    {
        return this.setEmeraldPriceFor(emeralds, item, 1);
    }
    
    public RandomTradeBuilder setEmeraldPrice(int min, int max)
    {
        return this.setPrice(Items.EMERALD, min, max);
    }
    
    public RandomTradeBuilder setEmeraldPriceFor(int min, int max, Item item, int amt)
    {
        this.setEmeraldPrice(min, max);
        return this.setForSale((random) -> new ItemStack(item, amt));
    }
    
    public RandomTradeBuilder setEmeraldPriceFor(int min, int max, Item item)
    {
        return this.setEmeraldPriceFor(min, max, item, 1);
    }
    
    public boolean canBuild()
    {
        return this.price != null && this.forSale != null;
    }
    
    public ITrade build()
    {
        return (entity, random) -> !this.canBuild() ? null : new MerchantOffer(this.price.apply(random), this.price2.apply(random), this.forSale.apply(random), this.maxTrades, this.xp, this.priceMult);
    }
    
    public static Function<Random, ItemStack> createFunction(Item item, int min, int max)
    {
        return (random) -> new ItemStack(item, random.nextInt(max) + min);
    }
}

 

Reflection Fix

    private static Method blockStatesInjector;
    
    static
    {
        try
        {
            blockStatesInjector = PointOfInterestType.class.getDeclaredMethod("func_221052_a", PointOfInterestType.class);
            blockStatesInjector.setAccessible(true);
        }
        catch (NoSuchMethodException | SecurityException e)
        {
            e.printStackTrace();
        }
    }
    
    public static void fixPOITypeBlockStates(PointOfInterestType poiType)
    {
        try
        {
            blockStatesInjector.invoke(null, poiType);
        }
        catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException e)
        {
            e.printStackTrace();
        }
    }

 

Edited January 10, 2020 by CAS_ual_TY

[CAS_ual_TY]

Going to bump this one time (I could not find forum rules on bumping, but I dont intend to do it anymore here anyways). Some (new) things:

 

- Still could not find a way to do it without reflection. Forge will probably have to step in there (Idk Im too afraid to ask or ping anyone). But I totally forgot about the reflection helper, so you should probably change the reflection fix to use the following (this already does the setAccessible(true) call, so just get the method using this):

        blockStatesInjector = ObfuscationReflectionHelper.findMethod(PointOfInterestType.class, "func_221052_a", PointOfInterestType.class);

 

- There is a more modern way to register stuff which you probably wanna use. I have not known about it (like most others) so I will just put that here for the sake of progress:

 

[desht]

Nice write-up!  That mysterious final int parameter to the PointOfInterestType#register() call you mentioned is related to pathfinding - I actually encountered this from the other side when porting PneumaticCraft's drone pathfinding to 1.14.  As I understand it, it's passed to Path#getPathToPos() and shortens the returned path by that number of blocks, so at a guess would make the villager move to a position that is 1 block away (by default) from the POI.

 

I suppose if a modded villager had a point of interest which was part of a big multiblock structure, you could increase that parameter so the villager doesn't try to navigate into any other parts of the structure.

Edited January 10, 2020 by desht

[Kriptarus]

Thank you for the explanation, It help me a lot.

I'm starting to understand how Forge/MC works.

 

After adapting and testing i finally made Villagers recognizes my custom PointOfView and changes Profession.

For some reason i still stuck on setting trades for that new Profession, seems like the villagerTrades method is not been called (even when initialized in the mod constructor). Their GUI for trades doesn't appear and they shake heads like an Unemployed Villager.

 

Is there something that i need to pay more attention to understand it better?

 

[CAS_ual_TY]

You probably register the villagerTrades method wrongly.

 

[Kriptarus]

I found the problem!
Looking better at the villagerTrades and comparing with your suggestion, i notice that i forgot to add @subscribeEvent at the method.

 

So, basically, every new kind of event that i create, i must use @subscribeEvent for Forge recognizes then, right?