[Solved] [1.16.5] Custom capability doesn't save after player leaves world

[mclich]

So i made my custom capability and attach it to all players. I also made serialization and synchronization using my own packet (at least i think i do) to allow client (player) always access updated capability data after some changes. In my capability event handler class i've subscribed to PlayerLoggedInEvent and send updated data through my packet. The problem is the data just doesn't save after player leaves the world and sets to default values after player joins the world again. Any ideas how to fix that?

Edited November 30, 2021 by mclich

[diesieben07]

Post your code.

[mclich]

9 minutes ago, diesieben07 said:

Post your code.

Capability class:

public class ManaCapability
{
	public static final ResourceLocation LOCATION=new ResourceLocation(ElderNorseGods.MOD_ID, "mana");
	
	@CapabilityInject(IManaHandler.class)
	public static Capability<IManaHandler> CAP_INSTANCE=null;
	
	public static class ManaStorage implements IStorage<IManaHandler>
	{
		@Override
		public INBT writeNBT(Capability<IManaHandler> cap, IManaHandler manaHandler, Direction side)
		{
			CompoundNBT tag=new CompoundNBT();
			tag.putFloat("Mana", manaHandler.getMana());
			tag.putBoolean("Status", manaHandler.getStatus());
			return tag;
		}

		@Override
		public void readNBT(Capability<IManaHandler> cap, IManaHandler manaHandler, Direction side, INBT nbt)
		{
			manaHandler.setMana(((CompoundNBT)nbt).getFloat("Mana"));
			manaHandler.setStatus(((CompoundNBT)nbt).getBoolean("Status"));
		}
	}
	
	public static class ManaProvider implements ICapabilitySerializable<CompoundNBT>
	{
		private final ManaHandler mana=new ManaHandler();
		private final LazyOptional<IManaHandler> manaOptional=LazyOptional.of(()->this.mana);
		
		public void invalidate()
		{
			this.manaOptional.invalidate();
		}
		
		@Override
		public CompoundNBT serializeNBT()
		{
			if(ManaCapability.CAP_INSTANCE==null) return new CompoundNBT();
			else return (CompoundNBT)ManaCapability.CAP_INSTANCE.writeNBT(this.mana, null);
		}

		@Override
		public void deserializeNBT(CompoundNBT nbt)
		{
			if(ManaCapability.CAP_INSTANCE!=null) ManaCapability.CAP_INSTANCE.readNBT(this.mana, null, nbt);
		}
		
		@Override
		public <T> LazyOptional<T> getCapability(Capability<T> cap, Direction side)
		{
			return cap==ManaCapability.CAP_INSTANCE?this.manaOptional.cast():LazyOptional.empty();
		}
	}
}

Capability handler class:

public class ManaHandler implements IManaHandler
{
	private float mana;
	private boolean active;
	
	public ManaHandler()
	{
		this.mana=0F;
		this.active=false;
	}
	
	@Override
	public void setMana(float amount)
	{
		if(amount<0F) this.mana=0F;
		else if(amount>20F) this.mana=20F;
		else this.mana=amount;
	}

	@Override
	public float getMana()
	{
		return this.mana;
	}

	@Override
	public void setStatus(boolean value)
	{
		this.active=value;
	}

	@Override
	public boolean getStatus()
	{
		return this.active;
	}

	@Override
	public void update(ServerPlayerEntity player)
	{
		NetworkHandler.sendToPlayer(player, new ManaDataPacket(this.getMana(), this.getStatus()));
	}
}

Capability event handler class:

@EventBusSubscriber(modid=ElderNorseGods.MOD_ID, bus=EventBusSubscriber.Bus.FORGE)
public abstract class ManaEventHandler
{
	private static void sendUpdates(ServerPlayerEntity player)
	{
		if(!player.getCommandSenderWorld().isClientSide())
		{
			player.getCapability(ManaCapability.CAP_INSTANCE).ifPresent(mana->mana.update(player));
		}
	}
	
	@SubscribeEvent
	public static void onPlayerChangedDimension(PlayerChangedDimensionEvent event)
	{
		ManaEventHandler.sendUpdates((ServerPlayerEntity)event.getPlayer());
	}
	
	@SubscribeEvent
	public static void onPlayerRespawn(PlayerRespawnEvent event)
	{
		ManaEventHandler.sendUpdates((ServerPlayerEntity)event.getPlayer());
	}
	
	@SubscribeEvent
	public static void onPlayerLoggedIn(PlayerLoggedInEvent event)
	{
		ManaEventHandler.sendUpdates((ServerPlayerEntity)event.getPlayer());
	}
	
	@SubscribeEvent
	public static void onPlayerClone(PlayerEvent.Clone event)
	{
		if(!event.isWasDeath()) return;
		IManaHandler oldMana=event.getOriginal().getCapability(ManaCapability.CAP_INSTANCE).orElse(null);
		IManaHandler newMana=event.getPlayer().getCapability(ManaCapability.CAP_INSTANCE).orElse(null);
		if(oldMana!=null&&newMana!=null)
		{
			newMana.setMana(oldMana.getMana());
			newMana.setStatus(oldMana.getStatus());
		}
	}
}

Packet class:

public class ManaDataPacket
{
	private float value;
	private boolean status;
	
	public ManaDataPacket(float value, boolean status)
	{
		this.value=value;
		this.status=status;
	}
	
	public static void encode(ManaDataPacket packet, PacketBuffer buffer)
	{
		buffer.writeFloat(packet.value);
		buffer.writeBoolean(packet.status);
	}
	
	public static ManaDataPacket decode(PacketBuffer buffer)
	{
		return new ManaDataPacket(buffer.readFloat(), buffer.readBoolean());
	}
	
	public static void handle(ManaDataPacket packet, Supplier<NetworkEvent.Context> ctx)
	{
		ctx.get().enqueueWork(()->DistExecutor.unsafeRunWhenOn(Dist.CLIENT, ()->()->PacketHandler.handlePacket(packet, ctx)));
		ctx.get().setPacketHandled(true);
	}
	
	private static class PacketHandler
	{
		private static void handlePacket(ManaDataPacket packet, Supplier<NetworkEvent.Context> ctx)
		{
			Minecraft mc=Minecraft.getInstance();
			mc.player.getCapability(ManaCapability.CAP_INSTANCE).ifPresent
			(
				mana->
				{
					mana.setMana(packet.value);
					mana.setStatus(packet.status);
				}
			);
		}
	}
}

[diesieben07]

Where are you modifying the values?

[mclich]

2 minutes ago, diesieben07 said:

Where are you modifying the values?

At the moment i have only one item that change values after use. There is code:
 

public class ManaTinctureItem extends Item
{
	public static final String ID="mana_tincture";
	
	public ManaTinctureItem()
	{
		super(new Item.Properties().food(new Food.Builder().nutrition(2).saturationMod(0.6F).alwaysEat().build()).stacksTo(1).rarity(Rarity.RARE).tab(ENGTabs.FOOD));
	}
	
	@Override
	public ItemStack finishUsingItem(ItemStack itemStack, World world, LivingEntity entity)
	{
		itemStack=entity.eat(world, itemStack);
		if(!world.isClientSide()&&entity instanceof ServerPlayerEntity)
		{
			ServerPlayerEntity player=(ServerPlayerEntity)entity;
			player.getCapability(ManaCapability.CAP_INSTANCE).ifPresent
			(
				mana->
				{
					if(!mana.getStatus())
					{
						mana.setStatus(true);
						mana.setMana(20F);
						mana.update(player);
					}
				}
			);
			if(player.gameMode.isSurvival())
			{
				if(itemStack.getCount()==0&&!player.inventory.contains(new ItemStack(Items.BOWL)))
				{
					player.inventory.removeItem(itemStack);
					player.inventory.add(player.inventory.selected, new ItemStack(Items.BOWL));
				}
				else player.inventory.add(new ItemStack(Items.BOWL));
			}
		}
		return itemStack;
	}
	
	@Override
	public boolean isFoil(ItemStack itemStack)
	{
		return true;
	}
}

 

[diesieben07]

Are the NBT serialization methods called? Do they operate correctly? Check using the debugger.

[mclich]

16 minutes ago, diesieben07 said:

Are the NBT serialization methods called? Do they operate correctly? Check using the debugger.

If i understood correctly, something is broken here. When i check for capability instance being null:

@Override
public CompoundNBT serializeNBT()
{
	if(ManaCapability.CAP_INSTANCE==null) return new CompoundNBT();
	else return (CompoundNBT)ManaCapability.CAP_INSTANCE.writeNBT(this.mana, null);
}

it always returns true, so serializeNBT() always returns new CompoundNBT(), i don't know why

Edited November 29, 2021 by mclich

[diesieben07]

Show where you register your capability.

And this "Oh, it's null... guess I'll do nothing then and not report this error" behavior is terrible. This is not PHP. If something so fundamental is wrong, throw an exception! Crashing the game is OK if your code has bugs. Don't try to sweep the errors under the rug. It makes things way more hard to debug.

[mclich]

6 hours ago, diesieben07 said:

Show where you register your capability.

 

@EventBusSubscriber(modid=ElderNorseGods.MOD_ID, bus=EventBusSubscriber.Bus.FORGE)
public abstract class ENGCapabilities
{
	@SubscribeEvent
	public static void registerCapabilities(final FMLCommonSetupEvent event)
	{
		CapabilityManager.INSTANCE.register(IManaHandler.class, new ManaStorage(), ManaHandler::new);
	}
	
	@SubscribeEvent
	public static void attachCapabilities(final AttachCapabilitiesEvent<Entity> event)
	{
		if(!(event.getObject() instanceof PlayerEntity)) return;
		ManaProvider provider=new ManaProvider();
		event.addCapability(ManaCapability.LOCATION, provider);
		event.addListener(provider::invalidate);
	}
}

Edited November 30, 2021 by mclich

[diesieben07]

That is the wrong event bus for FMLCommonSetupEvent.

[mclich]

18 minutes ago, diesieben07 said:

That is the wrong event bus for FMLCommonSetupEvent.

My god, i'm an idiot... I changed registration class like this:

@EventBusSubscriber(modid=ElderNorseGods.MOD_ID, bus=EventBusSubscriber.Bus.MOD)
public abstract class ENGCapabilities
{
	@SubscribeEvent
	public static void registerCapabilities(final FMLCommonSetupEvent event)
	{
		CapabilityManager.INSTANCE.register(IManaHandler.class, new ManaStorage(), ManaHandler::new);
	}
	
	@EventBusSubscriber(modid=ElderNorseGods.MOD_ID, bus=EventBusSubscriber.Bus.FORGE)
	private static class AttachCapabilities
	{
		@SubscribeEvent
		public static void attachCapabilities(final AttachCapabilitiesEvent<Entity> event)
		{
			if(!(event.getObject() instanceof PlayerEntity)) return;
			ManaProvider provider=new ManaProvider();
			event.addCapability(ManaCapability.LOCATION, provider);
			event.addListener(provider::invalidate);
		}
	}
}

and it works now! Thank you for your help!