Hi!
I was trying to create a smoke projectile, that when hits the ground spawn some particles for a certain duration.
The problem is that, when the entity hits the ground, it don't spawn the particles at all.

Here is my projectile:

@OnlyIn(value = Dist.CLIENT, _interface = IRendersAsItem.class)
public class SmokeBulletEntity extends DamagingProjectileEntity implements IRendersAsItem {

    private static final ItemStack STACK = new ItemStack(ModItems.BULLET.get());

    private boolean activated;
    private int duration;

    public SmokeBulletEntity(World world) {
        super(ModEntities.SMOKE_BULLET.get(), world);
        this.activated = false;
    }

    @Override
    public ItemStack getItem() {
        return STACK;
    }

    @Override
    protected void onHitBlock(BlockRayTraceResult rayTraceResult) {
        if (this.activated)
            return;
        if (!this.level.isClientSide) {
            this.activate();
        }
        super.onHitBlock(rayTraceResult);
    }

    @Override
    protected void onHitEntity(EntityRayTraceResult entityRayTraceResult) {
        //Must be Empty
    }

    private void activate() {
        this.activated = true;
        this.duration = 200;
        this.setDeltaMovement(0, 0, 0);
        this.xPower = 0;
        this.yPower = 0;
        this.zPower = 0;
        System.out.println("Active Smoke Projectile");
    }

    @Override
    public void tick() {
        if (this.activated && !this.level.isClientSide) {
            //System.out.println(String.format("%f, %f, %f", this.getX(), this.getY(), this.getZ()));
            for (int i = 0; i < 100; i++) {
                this.level.addParticle(ParticleTypes.FLAME, this.getX(), this.getY() + i, this.getZ(), 0, 0, 0);
            }
            this.duration--;
            if (this.duration <= 0) {
                this.remove();
            }
        } else {
            super.tick();
        }
    }

    @Override
    public void addAdditionalSaveData(CompoundNBT nbt) {
        super.addAdditionalSaveData(nbt);
        nbt.putBoolean("activated", this.activated);
        nbt.putInt("duration", this.duration);
    }

    @Override
    public void readAdditionalSaveData(CompoundNBT nbt) {
        super.readAdditionalSaveData(nbt);
        if (nbt.contains("activated")) {
            this.activated = nbt.getBoolean("activated");
        }
        if (nbt.contains("duration")) {
            this.duration = nbt.getInt("duration");
        }
    }

    @Override
    public IPacket<?> getAddEntityPacket() {
        return NetworkHooks.getEntitySpawningPacket(this);
    }
}

Can somebody explain me why?

Thanks!

Ok, so where do i put the code for spawning particle?

Ok so, i changed the function Entity#tick

public void tick() {
        if (this.activated) {
            for (int i = 0; i < 100; i++) {
                this.level.addParticle(ParticleTypes.FLAME, this.getX(), this.getY() + i, this.getZ(), 0, 0, 0);
            }
            this.duration--;
            if (this.duration <= 0) {
                this.remove();
            }
        } else {
            super.tick();
        }
    }

But still the bullet does not show the particles. There are only those of the basic bullet:

Why this happen?

How can i set the data on the client side?

The methods Entity#addAdditionalSaveData and Entity#readAdditionalSaveData doesn't do that?

54 minutes ago, Yurim64 said:

How can i set the data on the client side?

The methods Entity#addAdditionalSaveData and Entity#readAdditionalSaveData doesn't do that?

if the code above is still partly up-to-date, then it is due to the onHitBlock method because you only set the activate method on the server side

Edit: Entity#addAdditionalSaveData and Entity#readAdditionalSaveData these methods only save and write the data of the entity

Edited June 18, 20214 yr by Luis_ST

Ok so, i changed the entity in this way:

 

public class SmokeBulletEntity extends DamagingProjectileEntity implements IRendersAsItem {


    private static final DataParameter<Boolean> ACTIVATED = EntityDataManager.defineId(SmokeBulletEntity.class, DataSerializers.BOOLEAN);
    private static final ItemStack STACK = new ItemStack(ModItems.BULLET.get());

    private int duration;

    public SmokeBulletEntity(World world) {
        super(ModEntities.SMOKE_BULLET.get(), world);
    }

    @Override
    public ItemStack getItem() {
        return STACK;
    }

    @Override
    protected void onHitBlock(BlockRayTraceResult rayTraceResult) {
        if (this.isActivated())
            return;
        if (!this.level.isClientSide) {
            this.activate();
        }
        super.onHitBlock(rayTraceResult);
    }

    @Override
    protected void onHitEntity(EntityRayTraceResult entityRayTraceResult) {
        //Must be Empty
    }

    private void activate() {
        this.setActivated(true);
        this.duration = 200;
        this.setDeltaMovement(0, 0, 0);
        this.xPower = 0;
        this.yPower = 0;
        this.zPower = 0;
        System.out.println("Active Smoke Projectile");
    }

    @Override
    public void tick() {
        if (this.isActivated()) {
            for (int i = 0; i < 100; i++) {
                this.level.addParticle(ParticleTypes.FLAME, this.getX(), this.getY() + i, this.getZ(), 0, 0, 0);
            }
            this.duration--;
            if (this.duration <= 0) {
                this.remove();
            }
        } else {
            super.tick();
        }
    }

    @Override
    public void addAdditionalSaveData(CompoundNBT nbt) {
        super.addAdditionalSaveData(nbt);
        nbt.putBoolean("activated", this.isActivated());
        nbt.putInt("duration", this.duration);
    }

    @Override
    protected void defineSynchedData() {
        super.defineSynchedData();
        this.entityData.set(ACTIVATED, false);
    }

    public void setActivated(boolean activated) {
        this.entityData.set(ACTIVATED, activated);
    }

    public boolean isActivated() {
        return this.entityData.get(ACTIVATED);
    }

    @Override
    public EntityDataManager getEntityData() {
        return super.getEntityData();
    }

    @Override
    public void readAdditionalSaveData(CompoundNBT nbt) {
        super.readAdditionalSaveData(nbt);
        if (nbt.contains("activated")) {
            this.setActivated(nbt.getBoolean("activated"));
        }
        if (nbt.contains("duration")) {
            this.duration = nbt.getInt("duration");
        }
    }

    @Override
    public IPacket<?> getAddEntityPacket() {
        return NetworkHooks.getEntitySpawningPacket(this);
    }
}

But now, when i spawn it i encounter this error:

[15:39:10] [Server thread/FATAL] [minecraft/ThreadTaskExecutor]: Error executing task on Server
java.lang.NullPointerException: null
	at net.minecraft.network.datasync.EntityDataManager.set(EntityDataManager.java:122) ~[forge:?] {re:classloading}
	at com.ike.gunmod.entity.SmokeBulletEntity.defineSynchedData(SmokeBulletEntity.java:93) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
	at net.minecraft.entity.Entity.<init>(Entity.java:216) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.entity.projectile.ProjectileEntity.<init>(ProjectileEntity.java:25) ~[forge:?] {re:classloading}
	at net.minecraft.entity.projectile.DamagingProjectileEntity.<init>(DamagingProjectileEntity.java:26) ~[forge:?] {re:classloading}
	at com.ike.gunmod.entity.SmokeBulletEntity.<init>(SmokeBulletEntity.java:35) ~[?:?] {re:classloading,pl:runtimedistcleaner:A}
	at com.ike.gunmod.item.gun.SmokeGunItem.getBullet(SmokeGunItem.java:32) ~[?:?] {re:classloading}
	at com.ike.gunmod.item.gun.AbstractGunItem.use(AbstractGunItem.java:42) ~[?:?] {re:classloading}
	at net.minecraft.item.ItemStack.use(ItemStack.java:217) ~[forge:?] {re:classloading,xf:fml:forge:filled_map.4,xf:fml:forge:itemstack}
	at net.minecraft.server.management.PlayerInteractionManager.useItem(PlayerInteractionManager.java:287) ~[forge:?] {re:classloading}
	at net.minecraft.network.play.ServerPlayNetHandler.handleUseItem(ServerPlayNetHandler.java:982) ~[forge:?] {re:classloading}
	at net.minecraft.network.play.client.CPlayerTryUseItemPacket.handle(CPlayerTryUseItemPacket.java:28) ~[forge:?] {re:classloading}
	at net.minecraft.network.play.client.CPlayerTryUseItemPacket.handle(CPlayerTryUseItemPacket.java:9) ~[forge:?] {re:classloading}
	at net.minecraft.network.PacketThreadUtil.lambda$ensureRunningOnSameThread$0(PacketThreadUtil.java:19) ~[forge:?] {re:classloading}
	at net.minecraft.util.concurrent.TickDelayedTask.run(TickDelayedTask.java:17) ~[forge:?] {re:classloading}
	at net.minecraft.util.concurrent.ThreadTaskExecutor.doRunTask(ThreadTaskExecutor.java:136) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.util.concurrent.RecursiveEventLoop.doRunTask(RecursiveEventLoop.java:22) ~[forge:?] {re:classloading}
	at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:734) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.server.MinecraftServer.doRunTask(MinecraftServer.java:159) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.util.concurrent.ThreadTaskExecutor.pollTask(ThreadTaskExecutor.java:109) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.server.MinecraftServer.pollTaskInternal(MinecraftServer.java:717) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.server.MinecraftServer.pollTask(MinecraftServer.java:711) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.util.concurrent.ThreadTaskExecutor.managedBlock(ThreadTaskExecutor.java:119) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.server.MinecraftServer.waitUntilNextTick(MinecraftServer.java:697) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:646) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:232) ~[forge:?] {re:classloading,pl:accesstransformer:B}
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_231] {}

Why this happen?