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Hey all, I've gotten myself into a little problem I have absolutely no clue how to fix. Let's go down the issue shall we? :D

 

So I wanted to create a "portal" entity that could teleport the player wherever there was another portal. I got that to work. Good.

Then I wanted the player to be able to change the color of the portal to allow for multiple portals, that works, until the player logs out. Then the color would reset. So I did some looking up and found two ways to handle this issue, I could either use packets (which I found wouldn't be worth it due to the little bit I wanted to do) or I could use a DataWatcher like all the other entities seemed to use (thinking sheep). So I gave it a shot, and it seemed to work, portal teleportation stayed working, and the color still changed, but when I logged out and back in, it reset. After doing some digging I looked at the code and did some debugging to find that it seems that the DataWatcher doesn't seem to save everything properly, the data object that I was writing kept getting overridden. I'm not entirely sure I understand why either, I tried very many things, and then wound up copying the code from the sheep to get their color of wool, only to not have that work either. So here is the entire code for the entity, thanks for the help guys!

 

tl;dr

 

I have an int that I am using to store the color of an entity, it doesn't save.

 

package id.cutrone.lights.entities;

import id.cutrone.lights.blocks.PortalSpawner;

import java.util.ArrayList;
import java.util.List;

import net.minecraft.block.Block;
import net.minecraft.entity.Entity;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.util.DamageSource;
import net.minecraft.util.Vec3i;
import net.minecraft.world.World;

import com.google.common.base.Predicate;

public class EntityPortal extends Entity{

public List<EntityPortal> portals;
public int color = 0;

public EntityPortal(World worldIn){
        super(worldIn);
        this.preventEntitySpawning = true;
        this.setSize(1F, 1F);
    }

    public EntityPortal(World worldIn, double p_i1713_2_, double p_i1713_4_, double p_i1713_6_) {
        this(worldIn);
        this.setPosition(p_i1713_2_ + 0.5F, p_i1713_4_ + 1F, p_i1713_6_ + 0.5F);
        this.motionX = 0.0D;
        this.motionY = 0.0D;
        this.motionZ = 0.0D;
        this.prevPosX = p_i1713_2_;
        this.prevPosY = p_i1713_4_;
        this.prevPosZ = p_i1713_6_;
    }

    public void interact(EntityPlayer entityPlayer) {
    	setEntities();
    	int lastInChain = 0;
    	int thisInChain = 0;
    	int firstInChain = 0;
    	for(int i = 0; i < portals.size(); i++){
    		if(portals.get(i) == this){
    			thisInChain = i;
    		}
    	}
    	for(int i = 0; i < portals.size(); i++){
    		if(portals.get(i).color == this.color){
    			firstInChain = i;
    			break;
    		}
    	}
    	for(int i = 0; i < portals.size(); i++){
    		if(portals.get(i).color == this.color ){
    			lastInChain = i;
    		}
    	}
    	
    	if(thisInChain >= lastInChain && thisInChain != firstInChain){
    		entityPlayer.setPosition(portals.get(firstInChain).posX, portals.get(firstInChain).posY, portals.get(firstInChain).posZ);
    		return;
    	}
    	for(int i = 0; i < portals.size(); i++){
    		if(i > thisInChain && portals.get(i).color == this.color){
    			entityPlayer.setPosition(portals.get(i).posX, portals.get(i).posY, portals.get(i).posZ);
    			break;
    		}
    	}
    }
    
    /**
     * Called when the entity is attacked.
     */
    public boolean attackEntityFrom(DamageSource source, float amount)
    {
        return true;
    }

    /**
     * Returns true if other Entities should be prevented from moving through this Entity.
     */
    public boolean canBeCollidedWith(){
        return true;
    }

    /**
     * Will get destroyed next tick.
     */
    public void setDead(){
        super.setDead();
    }

    /**
     * Called to update the entity's position/logic.
     */
    public void onUpdate(){
    	this.worldObj.theProfiler.startSection("entityBaseTick");
    	this.ticksExisted++;
    	if(!worldObj.isRemote){
    	Block block = worldObj.getBlockState(this.getPosition().subtract(new Vec3i(0, 1, 0))).getBlock();
    	if(!(block instanceof PortalSpawner)){
    		this.setDead();
    	}else{
    		PortalSpawner ps = ((PortalSpawner)block);
    		ps.portal = this;
    	}
    	}
    	this.worldObj.theProfiler.endSection();
    }
    /**
     * Returns true if this cart can be ridden by an Entity.
     * @return True if this cart can be ridden.
     */
    public boolean canBeRidden(){
        return false;
    }

@Override
protected void entityInit() {
	this.dataWatcher.addObject(16, new Byte((byte)0));
	setEntities();
}

@SuppressWarnings("unchecked")
public void setEntities(){
	portals = new ArrayList<EntityPortal>();
	portals = worldObj.getEntities(EntityPortal.class, new Predicate(){
            public boolean apply(Object obj){
                return (Entity)obj instanceof EntityPortal;
            }});
}

@Override
protected void readEntityFromNBT(NBTTagCompound tagCompound) {
	color = dataWatcher.getWatchableObjectByte(16);
	this.setColor(tagCompound.getByte("Color"));
}

@Override
protected void writeEntityToNBT(NBTTagCompound tagCompound) {
	 tagCompound.setByte("Color", (byte)this.getColor());
}

public int getColor(){
	return this.dataWatcher.getWatchableObjectByte(16) & 15;
}

public void setColor(int color){
	this.color = color;
	byte b0 = this.dataWatcher.getWatchableObjectByte(16);
        this.dataWatcher.updateObject(16, Byte.valueOf((byte)(b0 & 240 | color & 15)));
}
}

Posted

Okay, so I got rid of the color field and that fixed everything.

 

And yes, the 16 colors should be enough, I didn't want that many different portals, but I wanted to provide a few different colors, and you can cycle through portals, so let's say you have 4 red portals, then you can teleport from portal to portal to portal. I can always change it from a byte to an int if I need to.

 

Thanks a bunch Diesie!

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