Hello everyone!

 

I want to create a beam consisting out of several entities in a row. But, for some reason I don't understand, the first entity of the row is moved to 0:0:0 after some time, but only on client side! I debugged a bit and found out that a packet of the class S15PacketEntityRelMove is received and moves the entity to 0:0:0. A bit weird is, that after some time the original position is restored, but the entity still isn't rendered.

The entity's position is never set to 0 from server side. It is even set to the owner's position every tick (which is not 0:0:0!).

 

Any ideas how this could happen? And how I can fix it?

 

Is it a problem that the entity is inside it's owner?

Code would be nice, like the method you use to spawn the entity.

OK:

 

Spawn:

this.controlledEntity = new EntityMagicBeam(this.getWorld(), this);
this.controlledEntity.setMainMagic(MAX_BEAM_LENGTH, ElementUtil.getMainElement(Arrays.asList(this.getMagicData().getElements())));
this.getWorld().spawnEntityInWorld(this.controlledEntity);

 

Every tick after this:

this.controlledEntity.setBeamDirection(this.getEntity().getLookVec());
this.controlledEntity.setPosition(this.getEntity().posX, this.getEntity().posY + this.getEntity().getEyeHeight() - 0.25, this.getEntity().posZ);
this.getEntity().addPotionEffect(new PotionEffect(Potion.moveSlowdown.id, 5));

if (this.callCount >= MAX_BEAM_TIME)
this.controlledEntity.setDead();

(this.getEntity() returns the owner here)

 

Entity class itself:

 

public class EntityMagicBeam extends Entity implements IMagicTransmitter, IEntityAdditionalSpawnData {

protected TaskGeneratedBeam controllingTask;
protected boolean isMainMagicEntity;
protected int childNumber;
protected int maxChildCount;
protected EntityMagicBeam child;
protected EntityMagicBeam parent;
protected Vec3 beamDirection;
protected Element mainElement;

public EntityMagicBeam(World worldIn) {
	super(worldIn);
	this.setSize(0.75f, 0.75f);
}

public EntityMagicBeam(World worldIn, TaskGeneratedBeam task) {
	this(worldIn);
	this.controllingTask = task;
}

public void setMainMagic(int maxChildCount, Element mainElement) {
	this.isMainMagicEntity = true;
	this.childNumber = 0;
	this.maxChildCount = maxChildCount;
	this.parent = null;
	this.mainElement = mainElement;
}

public void setBeamDirection(Vec3 direction) {
	this.beamDirection = direction;
	this.dataWatcher.updateObject(20, new Rotations((float) direction.xCoord, (float) direction.yCoord, (float) direction.zCoord));
}

@Override
public void onUpdate() {
	super.onUpdate();
	if (!this.worldObj.isRemote) {
		if (!this.isMainMagicEntity && (this.parent == null || this.parent.isDead)) {
			this.setDead();
			return;
		}
		if (!this.isDead && this.childNumber < this.maxChildCount && (this.child == null || this.child.isDead)) {
			this.child = new EntityMagicBeam(this.worldObj, this.controllingTask);
			this.child.childNumber = this.childNumber + 1;
			this.child.maxChildCount = this.maxChildCount;
			this.child.mainElement = this.mainElement;
			this.child.parent = this;
			this.updateChildPosition();
			this.dataWatcher.updateObject(21, new Integer(this.child.getEntityId()));
			this.worldObj.spawnEntityInWorld(this.child);
		}
	}
	if (this.isBurning())
		this.extinguish();

	if (this.child != null && !this.worldObj.isRemote) {
		this.updateChildPosition();
	} else if (this.worldObj.isRemote) {
		this.child = (EntityMagicBeam) this.worldObj.getEntityByID(this.dataWatcher.getWatchableObjectInt(21));
	}

	if (this.worldObj.isRemote) {
		Rotations r = this.dataWatcher.getWatchableObjectRotations(20);
		this.beamDirection = new Vec3(r.getX(), r.getY(), r.getZ());
	}

	Log.info_("I'm here (%s) at %s,%s,%s", this.getEntityId(), this.posX, this.posY, this.posZ);
}

protected void updateChildPosition() {
	if (this.beamDirection != null) {
		if (!this.worldObj.isRemote)
			this.child.setBeamDirection(this.beamDirection);
		this.child.setPosition(this.posX + this.beamDirection.xCoord * 0.5, this.posY + this.beamDirection.yCoord * 0.5, this.posZ + this.beamDirection.zCoord * 0.5);
	}
}

@Override
public void setDead() {
	super.setDead();
	if (this.child != null)
		this.child.setDead();
}

@Override
public MagicData getMagicData() {
	return this.controllingTask.getMagicData();
}

@Override
public EntityLivingBase getOwner() {
	return this.controllingTask.getEntity();
}

@Override
public void abortMagic() {
	this.controllingTask.abort();
}

public Vec3 getBeamDirection() {
	return this.beamDirection;
}

public Element getMainElement() {
	return this.mainElement;
}

@Override
public boolean writeToNBTOptional(NBTTagCompound tagCompund) {
	return false;
}

@Override
protected void readEntityFromNBT(NBTTagCompound tagCompund) {
}

@Override
protected void writeEntityToNBT(NBTTagCompound tagCompound) {
}

@Override
protected void entityInit() {
	this.dataWatcher.addObject(20, new Rotations(0, 0, 0));
	this.dataWatcher.addObject(21, new Integer(0));
}

@Override
public void writeSpawnData(ByteBuf buffer) {
	buffer.writeByte(this.mainElement.getID());
}

@Override
public void readSpawnData(ByteBuf buffer) {
	byte b = buffer.readByte();
	if (b < 16 && b > 0)
		this.mainElement = Element.values()[b];
}
}

 

You have to set the position before you spawn it.

Yes, this worked!

 

Although I don't really understand why...