Help with attributes

Hey guys, I'm currently trying to find out how to modify specific attributes of entities and items. I started with a simple method which should modify the attack strength of an entity, but when I use this method the entity instantly dies and I have no idea why...

That's my code:

Code:java

public static void changeAttackDamage(LivingEntity le, double damage) {
        EntityLiving el = ((CraftLivingEntity) le).getHandle();
        NBTTagCompound nbt = new NBTTagCompound();
        el.b(nbt);
        NBTTagList list = nbt.getList("Attributes");
        NBTTagList nlist = new NBTTagList();
        for (int i = 0; i < list.size(); i++) {
            AttributeModifier am = GenericAttributes.a((NBTTagCompound) list.get(i));
            AttributeModifier nam = am;
            String name = am.b();
            if (name.equals("generic.attackDamage")) {
                nam = new AttributeModifier(am.b(), damage, am.c());
            }
            nlist.add(AttributeChanger.convertToNBT(nam));
        }
        nbt.set("Attributes", nlist);
        el.a(nbt);
    }
 
    private static NBTTagCompound convertToNBT(AttributeModifier am) {
        NBTTagCompound nbtTagCompound = new NBTTagCompound();
        nbtTagCompound.setString("Name", am.b());
        nbtTagCompound.setDouble("Amount", am.d());
        nbtTagCompound.setInt("Operation", am.c());
        nbtTagCompound.setLong("UUIDMost", am.a().getMostSignificantBits());
        nbtTagCompound.setLong("UUIDLeast", am.a().getLeastSignificantBits());
        return nbtTagCompound;
    }

T3h Cr33p3r I know that this is possible, but potion effects multiply the base damage and attributes make it possible to change the base damage and much more

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

It's probably because you are setting it up incorrectly. An attribute is a NBTTag that contains a string 'Name' a double 'Base' value and then a list of 'Modifiers'. each modifier then contains what you are currently trying to use as the entire attribute.

http://www.minecraftwiki.net/wiki/Chunk_format#Mobs
http://www.minecraftwiki.net/wiki/Attribute#Modifiers

 

Jogy34 Does this mean that I have to Make a list where I add the modified list and apply it to the NBT tag or what? Could you post some code so I could see how to do it? I don't understand all this NBT stuff :/

T3h Cr33p3r Well I'm trying to modify the new attributes that have been implemented in 1.6 not messing around with potion effects... The attack strength is just a test, you can modify even more stuff which is not possible with potion effects!

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

This is what I made to add attributes to items:
https://github.com/Cybermaxke/Bukki...s/internal/attribute/CraftAttributeUtils.java

 

Cybermaxke Thanks, I'll see if it helps me to make my methods work

EDIT: That didn't help me either, the entity still just dies... That's my current code:

Code:java

    public static void changeAttackDamage(LivingEntity le, double damage) {
        EntityLiving el = ((CraftLivingEntity) le).getHandle();
        NBTTagCompound tag = new NBTTagCompound();
        el.b(tag);
        NBTTagList list = new NBTTagList();
        list.add(getTag(new AttributeModifier("generic.attackDamage", damage, 0)));
        for (AttributeModifier modifier : getModifiers(el)) {
            if (!modifier.b().equals("generic.attackDamage")) {
                list.add(getTag(modifier));
            }
        }
        tag.set("Attributes", list);
        el.a(tag);
    }
 
    public static List<AttributeModifier> getModifiers(EntityLiving el) {
        List<AttributeModifier> modifiers = new ArrayList<AttributeModifier>();
        NBTTagCompound tag = new NBTTagCompound();
        el.b(tag);
        NBTTagList taglist = tag.getList("Attributes");
        List<NBTBase> list = getList(taglist);
        Iterator<NBTBase> iter = list.iterator();
        while (iter.hasNext()) {
            NBTTagCompound tag2 = (NBTTagCompound) iter.next();
            modifiers.add(getModifier(tag2));
        }
        return modifiers;
    }
 
    @SuppressWarnings("unchecked")
    public static List<NBTBase> getList(NBTTagList list) {
        try {
            Field f = NBTTagList.class.getDeclaredField("list");
            f.setAccessible(true);
            return (List<NBTBase>) f.get(list);
        } catch (Exception e) {
            e.printStackTrace();
        }
 
        return null;
    }
 
    private static NBTTagCompound getTag(AttributeModifier modifier) {
        NBTTagCompound tag = new NBTTagCompound();
        tag.setString("Name", modifier.b());
        tag.setDouble("Amount", modifier.d());
        tag.setInt("Operation", modifier.c());
        tag.setLong("UUIDMost", modifier.a().getMostSignificantBits());
        tag.setLong("UUIDLeast", modifier.a().getLeastSignificantBits());
        return tag;
    }
 
    public static AttributeModifier getModifier(NBTTagCompound tag) {
        String name = tag.getString("Name");
        double amount = tag.getDouble("Amount");
        int operation = tag.getInt("Operation");
        UUID id = new UUID(tag.getLong("UUIDMost"), tag.getLong("UUIDLeast"));
        return new AttributeModifier(id, name, amount, operation);
    }

 

Code:

NBTTagCompound attributes = new NBTTagCompound();
attributes.addString("Name", "generic.attackDamage");
attributes.addDouble("Amount", 10.0);
NBTTagList modifiers = new NBTTagList();
NBTTagCompound first = new NBTTagCompound();
first.addString("Name", "This is a Name");
first.addDouble("Amount", 10);
first.addInt("Opperation", 0); //Adds the amount to the base, 1 will multiply the base by the amount, 2 will multiply the current value by the amount
UUID uuid = UUID.randomUUID();
first.addLong("UUIDMost", uuid.getMostSignificantBits());
first.addLong("UUIDLeast", uuid.getLeastSignificantBits());
modifiers.add(first);
attributes.setList("Modifiers", modifiers);
//Give the mob the attributes tag here

I think this should work however it is completely untested so I'm not sure

Not true, you should be able to do it by using Craftbukkit/NMS code. A lot of people don't like using Craftbukkit or NMS code because it easily gets a lot more complicated and it has to be updated on every bukkit release due to the dynamically changing package names.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

T3h Cr33p3r
net.minecraft.server

 

net.minecraft.server, its one of the packages in the craftbukkit.jar file. The bukkit.jar just contains the Bukkit API, the Craftbukkit code in the craftbukkit.jar is the actual implementation of the Bukkit API interfaces, and the NMS code in the craftbukkit.jar is the actual server along with a few extra bits that allows the craftbukkit code to interface with it easier and is, well, what the craftbukkit code interfaces with. The craftbukkit.jar also contains the API

 

DarkBladee12
I will look into the attribute system for entities, cause its not using the same way.

 

Jogy34 Well your code doesn't work either... Cybermaxke If I just add a new attribute modifier for "generic.attackDamage" the zombie does only 1 damage instead of 2 - 3 no matter which value i choose for "Amount". If I just modify the amount off the current attribute modifier it won't do anything. That's the code I use for modifying the existant modifier:

Code:java

public static void changeAttackDamage(LivingEntity le, double damage) {
        EntityLiving el = ((CraftLivingEntity) le).getHandle();
        NBTTagCompound tag = new NBTTagCompound();
        el.b(tag);
        NBTTagList attributes = tag.getList("Attributes");
        NBTTagList list = new NBTTagList(attributes.getName());
        for (int i = 0; i < attributes.size(); i++) {
            NBTTagCompound tag2 = (NBTTagCompound) attributes.get(i);
            String name = tag2.getString("Name");
            if (name.equals("generic.attackDamage")) {
                tag2.setDouble("Amount", damage);
            }
            list.add(tag2);
        }
        tag.set("Attributes", list);
        el.a(tag);
    }

 

I am almost done adding attribute utils for entities.

Have fun
https://github.com/Cybermaxke/Bukki...s/internal/attribute/CraftAttributeUtils.java

DarkBladee12
The entity attributes are organized using a diffirent way so that is why it isn't working.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Cybermaxke Thanks for this, I'll look into it tomorrow

 

There are currently problems but I am fixing them now, so you will be able to see working code tomorrow.