[1.14.3] Syncing changes to capability

[eafooe]

Hi all,

I have made a capability (see spoiler) that I attach to vanilla VillagerEntity instances during the AttachCapabilitiesEvent<Entity>:

@SubscribeEvent
    public static void attachEntityCapabilities(AttachCapabilitiesEvent<Entity> event){
        if (event.getObject() instanceof VillagerEntity){
            event.addCapability(NoseProvider.IDENTIFIER, new NoseProvider());
        }
    }

Currently, the capability has one boolean, 'hasNose' which allows me to know whether the VillagerEntity instance has a nose, or whether it was removed by the player.

 

Spoiler

INose.java

public interface INose {
    boolean hasNose();
    void setHasNose(boolean hasNose);
}

 

Nose.java

public class Nose implements INose {
    private boolean hasNose = true;

    @Override
    public boolean hasNose() {
        return hasNose;
    }

    @Override
    public void setHasNose(boolean hasNose) {
        this.hasNose = hasNose;
    }
}

NoseStorage.java

public class NoseStorage implements Capability.IStorage<INose> {

    @Nullable
    @Override
    public INBT writeNBT(Capability<INose> capability, INose instance, Direction side) {
        VillagersNose.LOGGER.info("Writing HasNose: " + instance.hasNose() + " to NBT");
        CompoundNBT nbt = new CompoundNBT();
        nbt.putBoolean("HasNose", instance.hasNose());
        return nbt;
    }

    @Override
    public void readNBT(Capability<INose> capability, INose instance, Direction side, INBT nbt) {
        CompoundNBT hi = (CompoundNBT) nbt;
        instance.setHasNose(hi.getBoolean("HasNose"));
        VillagersNose.LOGGER.info("Read HasNose: " + hi.getBoolean("HasNose") + " from NBT");
        VillagersNose.LOGGER.info("HasNose is now equal to: " + instance.hasNose());
    }
}

NoseProvider.java

public class NoseProvider implements ICapabilitySerializable<INBT> {
    public static final ResourceLocation IDENTIFIER = new ResourceLocation(MODID, "capability_nose");

    @CapabilityInject(INose.class)
    public static Capability<INose> NOSE_CAP = null;

    private INose instance = NOSE_CAP.getDefaultInstance();

    @Override
    public INBT serializeNBT() {
        VillagersNose.LOGGER.info("Serializing NBT...");
        return NOSE_CAP.getStorage().writeNBT(NOSE_CAP, instance, null);
    }

    @Override
    public void deserializeNBT(INBT nbt) {
        VillagersNose.LOGGER.info("Deserializing NBT...");
        NOSE_CAP.getStorage().readNBT(NOSE_CAP, instance, null, nbt);
    }

    @Nonnull
    @Override
    public <T> LazyOptional<T> getCapability(@Nonnull Capability<T> cap, @Nullable Direction side) {
        return NOSE_CAP.orEmpty(cap, LazyOptional.of(() -> instance));
    }
}

 

If 'hasNose' is set to false, the VillagerEntity instance should render without a nose. I believe I need to send a packet from the server and to the client with this information during the events specified in the following quote?:

 

On 6/8/2019 at 8:12 AM, diesieben07 said:

To keep entity data up to date on the client you must sync in the following places:

• PlayerEvent.StartTracking when PlayerEvent.StartTracking#getTarget is your entity (or has your capability in this case). Send the packet to PlayerEvent.StartTracking#getEntityPlayer.
• EntityJoinWorldEvent when EntityJoinWorldEvent#getEntity is your entity (or has your capability in this case). Send the packet to all players tracking the entity (EntityTracker#getTrackingPlayers or use PacketDistributor.TRACKING_ENTITY when using NetworkRegistry.newSimpleChannel).
• Whenever the data changes send the packet to all players tracking the entity (see above).

I have a packet class set up, but I'm not sure what I should put in the handle method to make sure the client gets the data that it needs.

 

public class ClientPacket {
    private int entityId;

    public ClientPacket(int entityId){
        this.entityId = entityId;
    }

    static void encode(ClientPacket msg, PacketBuffer buffer){
        buffer.writeInt(msg.entityId);
        VillagersNose.LOGGER.info("Wrote entityId: " + buffer.readInt());
    }

    static ClientPacket decode(PacketBuffer buffer){
        int entityId = buffer.readInt();
        VillagersNose.LOGGER.info("Read entityId: " + entityId);
        return new ClientPacket(entityId);
    }

    // Send from server to client
    static void handle(ClientPacket msg, Supplier<NetworkEvent.Context> ctx){
        ctx.get().enqueueWork(() -> {
            // ?
          // ? I've tried all sorts of things here but nothing seems to work
          // ?
        });
        ctx.get().setPacketHandled(true);
    }
}

In addition to the handle method, I want to ensure that I am sending my packet correctly. Is the following code what I should be doing?

// Send to all players tracking entity
    @SubscribeEvent
    public static void entityJoinWorldEvent(EntityJoinWorldEvent event){
        Entity entity = event.getEntity();
        if (entity instanceof VillagerEntity && !event.getWorld().isRemote){
            PacketDistributor.PacketTarget dest = PacketDistributor.TRACKING_ENTITY.with(() -> entity);
            PacketHandler.INSTANCE.send(dest, new ClientPacket(entity.getEntityId()));
        }
    }

I know this is kind of a lengthy question, so thank you for taking your time to help me out.

Edited August 14, 2019 by eafooe

[Animefan8888]

3 hours ago, eafooe said:

static void encode(ClientPacket msg, PacketBuffer buffer){

You should also probably write into the packet buffer the boolean about the nose here. And then of course retrieve it where in decode.

 

3 hours ago, eafooe said:

static void handle(ClientPacket msg, Supplier<NetworkEvent.Context> ctx){

Then here get the entity from the ID and then change the nose value.

3 hours ago, eafooe said:

public static void entityJoinWorldEvent(EntityJoinWorldEvent event){

This is the wrong event. Use the PlayerEvent.StartTracking

[loordgek]

11 hours ago, eafooe said:

return NOSE_CAP.orEmpty(cap, LazyOptional.of(() -> instance));

make a field holding the LazyOptional that makes it possible to cache the capability

[eafooe]

6 hours ago, loordgek said:

make a field holding the LazyOptional that makes it possible to cache the capability

Like this?

public class NoseProvider implements ICapabilitySerializable<INBT> {
    public static final ResourceLocation IDENTIFIER = new ResourceLocation(MODID, "capability_nose");

    @CapabilityInject(INose.class)
    public static Capability<INose> NOSE_CAP = null;

    private INose instance = NOSE_CAP.getDefaultInstance();
    private final LazyOptional<INose> holder = LazyOptional.of(() -> instance);

    @Override
    public INBT serializeNBT() {
        VillagersNose.LOGGER.info("Serializing NBT...");
        return NOSE_CAP.getStorage().writeNBT(NOSE_CAP, instance, null);
    }

    @Override
    public void deserializeNBT(INBT nbt) {
        VillagersNose.LOGGER.info("Deserializing NBT...");
        NOSE_CAP.getStorage().readNBT(NOSE_CAP, instance, null, nbt);
    }

    @Nonnull
    @Override
    public <T> LazyOptional<T> getCapability(@Nonnull Capability<T> cap, @Nullable Direction side) 	   {
        return NOSE_CAP.orEmpty(cap, holder);
    }
}

[eafooe]

10 minutes ago, diesieben07 said:

Don't blindly return your capability in getCapability. You must return an empty optional if the queried capability is not present in your provider.

Is this what you mean?

@Nonnull
    @Override
    public <T> LazyOptional<T> getCapability(@Nonnull Capability<T> cap, @Nullable Direction side) {
        if (cap == NOSE_CAP){
            return holder.cast();
        }
        return LazyOptional.empty();
    }

 

 

[loordgek]

no the other way was fine

@diesieben07 you really need to look at what "orEmpty" does, hint: it is in the name

[eafooe]

33 minutes ago, loordgek said:

no the other way was fine

@diesieben07 you really need to look at what "orEmpty" does, hint: it is in the name

Aren't they equivalent?

[loordgek]

yes but '' orEmpty " is shorter

 

return NOSE_CAP.orEmpty(cap, holder);

vs

        if (cap == NOSE_CAP){
            return holder.cast();
        }
        return LazyOptional.empty();

 

[loordgek]

not really LazyOptional can be used for anything but it intended to be used by cabability

10 hours ago, diesieben07 said:

Great naming then -_-. Why is it not OptionalCapability?

???????

https://github.com/MinecraftForge/MinecraftForge/commit/8e43dfa7a626387556e642f21aeb632e8e96cdba#diff-c3e85f4c50091d558045cf5dc0dac9b4

blame tterrag1098

[eafooe]

Thanks so much everyone; I have it working! 

I'm proud of my funky, little guy