[1.16.5]Help with capabilities

[cwJn]

I want to start developing a mod that adds different damage types to the game, but I'm not entirely sure where to begin. I looked at TerraFirmaCraft's code a bit, but it's for 1.12 so I'm reluctant to learn from it since it's so out of date. Would capabilities be the best option for implementing this? I've never had to use capabilities for any of my projects so far, so I'm not quite sure how they work.

[Draco18s]

You don't need capabilities to create a new damage type. You just call... new DamageType(...)

Super mega ultra old code, but its not like anything's changed much, if at all:

https://github.com/Draco18s/Decaying-World/blob/master/draco18s/decay/items/IceNineShard.java#L38

https://github.com/Draco18s/Decaying-World/blob/master/temp-7-26-13/draco18s/decay/ColdDamage.java#L11

Edited October 24, 2021 by Draco18s

[cwJn]

I'd eventually like to add damage resistance for specific damage types as well. I haven't looked into it, but would that also be possible without having to use capabilities? Thanks for the quick reply.

[Draco18s]

No, you would need capabilities for that (if an existing entity is resistant, or the player) unless only your own mobs are resistant.

[cwJn]

I was able to figure some stuff out and get it working. On a separate note, is there a way to get the item used by the attacking player in AttackEntityEvent?

[MFMods]

26 minutes ago, cwJn said:

I was able to figure some stuff out and get it working. On a separate note, is there a way to get the item used by the attacking player in AttackEntityEvent?

it depends on damage type somewhat, but event.getPlayer().getMainHandItem() should give you a sword, if you want to check enchantments or whatever.

[Draco18s]

Damage events don't have a player, you need to use event.getDamageSource() or event.getTrueSource()

Be aware of the following:

• Source may be null
• Source may not be a player

[cwJn]

Thanks for the advice, I'm now able to get the events working to a degree. The issue I'm having now is this:

I have a capability for both damage type and damage resistance. There are 3 new damage types that each have a corresponding resistance. Damage type capabilities are attached to weapons, while resistance capabilities are applied to entities. I use the following methods to apply extra damage types as well as calculate resistances. The problem is that when attacking an entity, only 1 instance of the new damage types is applied. As for the debugging messages, the 3 sendMessages are being sent in the extraDamage method. In the damageResistance method, only 1 System.out.println statement is being sent. Is there something to do with the way LivingHurtEvent works that only allowed 1 to be applied?

package com.cwjn.hardstuckintegration.Events;

import com.cwjn.hardstuckintegration.Capabilities.DamageTypes.CapabilityDamageTypes;
import com.cwjn.hardstuckintegration.Capabilities.DamageTypes.IDamageTypes;
import com.cwjn.hardstuckintegration.Capabilities.Resistances.CapabilityDamageResistance;
import com.cwjn.hardstuckintegration.Capabilities.Resistances.IDamageResistance;
import com.cwjn.hardstuckintegration.DamageTypes.ImpactDamage;
import com.cwjn.hardstuckintegration.DamageTypes.NewType;
import com.cwjn.hardstuckintegration.DamageTypes.PunctureDamage;
import com.cwjn.hardstuckintegration.DamageTypes.SlashDamage;
import com.cwjn.hardstuckintegration.HardstuckIntegration;
import net.minecraft.entity.Entity;
import net.minecraft.entity.LivingEntity;
import net.minecraft.entity.player.PlayerEntity;
import net.minecraft.item.ItemStack;
import net.minecraft.util.DamageSource;
import net.minecraft.util.Hand;
import net.minecraft.util.text.TranslationTextComponent;
import net.minecraftforge.event.entity.living.LivingHurtEvent;
import net.minecraftforge.event.entity.player.AttackEntityEvent;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.common.Mod;

@Mod.EventBusSubscriber(modid = HardstuckIntegration.modID)
public class DamageEvents {

    @SubscribeEvent
    public static void extraDamage(AttackEntityEvent event) {
        PlayerEntity player = event.getPlayer(); //player that is attacking
        Entity target = event.getTarget(); //target being attacked
        ItemStack item = player.getItemInHand(Hand.MAIN_HAND); //item used to attack

        if (item != null) {
            IDamageTypes damage = item.getCapability(CapabilityDamageTypes.DAMAGE_TYPES_CAPABILITY).orElse(null); //get the extra damage types
            if (damage != null) {
                float impactDamage = damage.getImpactDamage();
                float slashDamage = damage.getSlashDamage();  //store the extra damage types
                float punctureDamage = damage.getPunctureDamage();

                if (impactDamage > 0) {
                    player.sendMessage(new TranslationTextComponent("TARGET ENTITY DEALT: " + impactDamage + " POINTS OF IMPACT DAMAGE"), player.getUUID());
                    target.hurt(new ImpactDamage(), impactDamage); //if the item has extra impact damage, hurt the target with an instance of impact damage
                }
                if (slashDamage > 0) {
                    player.sendMessage(new TranslationTextComponent("TARGET ENTITY DEALT: " + slashDamage + " POINTS OF SLASH DAMAGE"), player.getUUID());
                    target.hurt(new SlashDamage(), slashDamage); //if the item has extra slash damage, hurt the target with an instance of slash damage
                }
                if (punctureDamage > 0) {
                    player.sendMessage(new TranslationTextComponent("TARGET ENTITY DEALT: " + punctureDamage + " POINTS OF PUNCTURE DAMAGE"), player.getUUID());
                    target.hurt(new PunctureDamage(), punctureDamage); //if the item has extra puncture damage, hurt the target with an instance of puncture damage
                }
            }
        }
    }

    @SubscribeEvent
    public static void damageResistance(LivingHurtEvent event) {
        DamageSource source = event.getSource(); //source of damage
        if (source instanceof NewType) { //check if the source is a subclass of the new damage types added with this mod
            float amount = event.getAmount(); //get initial amount of new damage, before resistances
            LivingEntity target = event.getEntityLiving(); //target of damage
            float newDamage = amount; //variable to hold post-resistance calculation damage

            IDamageResistance res = target.getCapability(CapabilityDamageResistance.DAMAGE_RESISTANCE_CAPABILITY).orElse(null); //get target's resistances
            if (res != null) {
                float impactRes = res.getImpactResistance();
                float slashRes = res.getSlashResistance(); //store the resistances
                float punctureRes = res.getPunctureResistance();

                switch (((NewType) source).getSourceAsString()) { //get the the source of damage as a string
                    case "slash":
                        if (slashRes > 0) newDamage = (amount * (100 / (100 + slashRes))); //if the target has resistances, apply math to reduce damage.
                        else if (slashRes < 0) newDamage = (amount * (2 - (100 / (100 - slashRes)))); //if the target has negative resistances, apply math to boost damage.
                        else newDamage = amount; //if the target has no resistances, apply initial damage unchanged
                        System.out.println("TARGET ENTITY TOOK: " + newDamage + " SLASH DAMAGE"); //used for debugging
                        break;
                    case "puncture": //same as case slash, but for puncture damage
                        if (punctureRes > 0) newDamage = (amount * (100 / (100 + punctureRes)));
                        else if (punctureRes < 0) newDamage = (amount * (2 - (100 / (100 - punctureRes))));
                        else newDamage = amount;
                        System.out.println("TARGET ENTITY TOOK: " + newDamage + " PUNCTURE DAMAGE");
                        break;
                    case "impact": //same as case slash, but for impact damage
                        if (impactRes > 0) newDamage = (amount * (100 / (100 + impactRes)));
                        else if (impactRes < 0) newDamage = (amount * (2 - (100 / (100 - impactRes))));
                        else newDamage = amount;
                        System.out.println("TARGET ENTITY TOOK: " + newDamage + " IMPACT DAMAGE");
                        break;
                }
            }
            event.setAmount(newDamage); //apply post-resistance calculation damage to the event
        }
    }

}

 

[Draco18s]

7 minutes ago, cwJn said:

switch (((NewType) source).getSourceAsString())

Why the fak are you to-stringing that?

if(source instanceof ImpactDamage) works just fine. You could also create single static instances of your new damage type and use things like ModDamageTypes.SLASHING and the == operator, like vanilla does. Your damage type instances have NO custom data in them at all, so you should just do that (yes I realize my own, very old, code is not following that).

7 minutes ago, cwJn said:

new TranslationTextComponent("TARGET ENTITY DEALT: " + impactDamage + " POINTS OF IMPACT DAMAGE")

This is not how localization works.

7 minutes ago, cwJn said:

if (item != null) {

ItemStacks are never null.

7 minutes ago, cwJn said:

ItemStack item = player.getItemInHand(Hand.MAIN_HAND); //item used to attack

The player could be, though.

7 minutes ago, cwJn said:

.orElse(null); //get the extra damage types
if (res != null) {

Use ifPresent() instead.

7 minutes ago, cwJn said:

System.out.println("TARGET ENTITY TOOK: " + newDamage + " SLASH DAMAGE"); //used for debugging

You should use the logger Forge provides you instead.

Edited October 25, 2021 by Draco18s