[need help] modify weapons damage( and other properties)

Plugins Plugin Development
1

Hello everyone,
I know that since minecraft vanilla 1.9, there is the possibility to change among other the damage of weapons when they are equipped. Like showed on the picture below

exemple
exemple854×480

Is there the possibility to create the same item programmatically with sponge?

2

Get/create the itemstack that you want

ItemType.WOOD_SWORD.getTemplate();

And then use data keys. This will help.

Keys.ATTACK_DAMAGE

Im sure there is one for attack speed

3

thank you for your answer,
I tried this but is not effective

ItemStackSnapshot itemStackSnapshot = ItemTypes.WOODEN_SWORD.getTemplate();
itemStackSnapshot.createStack().offer(Keys.ATTACK_DAMAGE,50.0d);

this error occur

java.lang.NullPointerException: null
        at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:257) ~[minecraft_server.1.12.2.jar:?]
        at org.spongepowered.common.data.SpongeManipulatorRegistry.getDelegate(SpongeManipulatorRegistry.java:308) ~[SpongeManipulatorRegistry.class:1.12.2-7.1.0-BETA-5]
        at org.spongepowered.common.data.util.DataUtil.getBaseValueProcessor(DataUtil.java:375) ~[DataUtil.class:1.12.2-7.1.0-BETA-5]
        at net.minecraft.item.ItemStack.get(SourceFile:1313) ~[aip.class:?]
        at org.spongepowered.common.item.inventory.SpongeItemStackSnapshot.get(SpongeItemStackSnapshot.java:303) ~[SpongeItemStackSnapshot.class:1.12.2-7.1.0-BETA-5]
        at com.ylinor.itemizer.Itemizer.preInit(Itemizer.java:48)
4

Offer to the itemstacksnapshot and then create.

5

I’ts look like the key Keys.ATTACK_DAMAGE is not supported by the item unlike the display name key.

ItemStackSnapshot itemStackSnapshot = ItemTypes.WOODEN_SWORD.getTemplate();
		ItemStack item = itemStackSnapshot.createStack();
		logger.info(""+ item.supports(Keys.ATTACK_DAMAGE));
		logger.info(""+ item.supports(Keys.DISPLAY_NAME));

console :

[21:31:55 INFO] [itemizer]: false
[21:31:55 INFO] [itemizer]: true

there must be a solution it’s possible to change attributeModifier via a chat command :
/give @p minecraft:stone_sword 1 0 {AttributeModifiers:[{AttributeName:"generic.attackDamage",Name:"dégats",Slot:"mainhand",Amount:10,Operation:0,UUIDMost:77976,UUIDLeast:134898}]}

6

Just seen in the keys class that it says for projectiles (dont know why i didn’t see that before). However I can not see a key for item damage. I know its not the best idea but you could run a command to set the attributes

7

I come back on this post 7 month later to solve the problem. I used the the unsafe data of a container to create an itemStack with a modified attack damage.


            ItemStack itemStack = ItemStack.builder().itemType(ItemTypes.DIAMOND_SWORD).build();

            List<DataContainer> containers = new ArrayList();

            DataContainer dataContainer = DataContainer.createNew();
            dataContainer.set(DataQuery.of("AttributeName"),"generic.attackDamage");
            dataContainer.set(DataQuery.of("Name"),"generic.attackDamage");
            dataContainer.set(DataQuery.of("Amount"),15);
            dataContainer.set(DataQuery.of("Operation"),0);
            dataContainer.set(DataQuery.of("Slot"),"mainhand");
            dataContainer.set(DataQuery.of("UUIDMost"),58736);
            dataContainer.set(DataQuery.of("UUIDLeast"),617612);

            containers.add(dataContainer);

            DataContainer c = itemStack.toContainer();
            c.set(DataQuery.of("UnsafeData","AttributeModifiers"),containers);

            ItemStack modifiedItem = ItemStack.builder().fromContainer(c).build();

            ((Player) src).setItemInHand(HandTypes.MAIN_HAND, modifiedItem);