[1.6.4]Problem with NBT, TEs and onItemUse

[skullywag]

Apologies for the vague title but couldnt fit it into one short sentence.

 

Simply I need to get at the nbt of a tile entity created when onItemUse does a setBlock:

 

public boolean onItemUse(ItemStack par1ItemStack, EntityPlayer par2EntityPlayer, World par3World, int par4, int par5, int par6, int par7, float par8, float par9, float par10)
    {
        if (par7 != 1)
        {
            return false;
        }
        else if (par2EntityPlayer.canPlayerEdit(par4, par5, par6, par7, par1ItemStack) && par2EntityPlayer.canPlayerEdit(par4, par5 + 1, par6, par7, par1ItemStack))
        {
            int i1 = par3World.getBlockId(par4, par5, par6);
            Block soil = Block.blocksList[i1];

            if (soil != null && soil == Block.cobblestoneMossy && soil.canBlockStay(par3World, par4, par5, par6) && par3World.isAirBlock(par4, par5 + 1, par6))
            {
                par3World.setBlock(par4, par5 + 1, par6, this.blockType);                
                --par1ItemStack.stackSize;
                TileEntity te = par3World.getBlockTileEntity(par4, par5+1, par6);
                return true;
            }
            else
            {
                return false;
            }
        }
        else
        {
            return false;
        }
    }

 

You can see where I grab the tile entity in the above code but that "te" doesnt let me "getEntityData" or anything else to get the tag. Is this possible and if not how do i transfer data about the item being used to the block/te it creates?

 

Am i again missing something plainly obvious.....(not having a good day for problem solving)

[coolAlias]

The TileEntity is created automatically when the block is placed. There is no 'getEntityData' for TileEntity, but you can get the TE from the world and set class fields accordingly, which will then be saved/loaded if you wrote your TE correctly.

 

You're on the right track:

par3World.setBlock(par4, par5 + 1, par6, this.blockType);                
--par1ItemStack.stackSize;
TileEntity te = par3World.getBlockTileEntity(par4, par5+1, par6);
// you've got the tile entity, now just make sure it's yours and do whatever you want with it:
if (te instanceof YourTileEntityClass) {
YourTileEntityClass myTile = (YourTileEntityClass) te;
// now you can use your tile entity class methods:
myTile.setSomeField(someValue);
// now some field = some value, which will save and load with the tile entity
}
return true;

[coolAlias]

@diesieben07 True, but I've had (reported by users with other mods loaded in addition to mine, so...) class cast exceptions thrown when accessing tile entities like that, so I throw in that extra check for good measure.

[skullywag]

Thanks guys, this was just a misunderstanding on my part of how I thought it worked (Java is not my main programming language in my day job), but a question does pop into my head after reading the above, granted I have access to the getter and setter for fields on the TE class so for this instance im good, but if i needed to how do i simply view whats currently in the NBT for the given entity, its something thats always bugged me and something ive not found anyone doing (probably because you wouldnt need it in the final code, debug only)

[coolAlias]

No one ever does it because the NBT tag for tile entities is only used to store the data between quitting and restarting the world, unlike that for ItemStacks which is often modified and referenced during the course of the game. Once the tile entity loads, all the data should be stored in local fields, which you can print normally for debugging.

 

If you really want to see what is in the NBT tag, then put your debugging messages in the read / write NBT methods.

[skullywag]

ok its becoming clearer, let me set out what im doing:

 

I have 16 meta items on an item ID, they use the getColorFromItemStack to set a colour to their icon based on a list of colours in the class(16 of them). In the onItemUse method once some checks have been passed it does a setBlock and sets a field on the TileEntity for this block to its metaID, the TileEntityRenderer grabs the metaID from the TE and converts it into a set of RGB colour floats (im probably doing this rather heavily but it works for now) it then uses glColor4f to set the colour to the block/te model when rendered. This all works fine I get coloured renders in world.

 

The issue now is if i log off and back on, all my blocks are grey/white (the orginal texture colour before the gl pass), based on what youve said above should I be saving the colour in NBT as it will then survive past a restart. I that correct? and if so where is the best place to do the write to NBT. I have always set NBT like:

 

NBTTagCompound nbt= tileEntity.getTagCompound();	
nbt.setBoolean("something",(boolean)true);

 

the issue I face is that the above doesnt seem to be posible from anywhere in the classes ive set out above, now this may be (and probably is) down to me screwing something up.

 

Or am i finally going ot have to start working out the madness that is packets...

[coolAlias]

If your block isn't using metadata for anything other than your rendering, why not just use the block's metadata value directly as stored in the world? world.setBlockMetatata(x, y, z, meta), then in your rendering class world.getBlockMetadata(x, y, z) done, you've got the index of the item responsible.

 

If that doesn't work for you for whatever reason, store the value as a field in the tile entity (making sure to save it in the tile entity's write / read NBT methods) and override the getDescriptionPacket method.

@Override
public void writeToNBT(NBTTagCompound compound) {
super.writeToNBT(compound);
compound.setInteger("key", value);
}

@Override
public void readFromNBT(NBTTagCompound compound) {
super.readFromNBT(compound);
yourField = compound.getInteger("key");
}

// now this will automatically synchronize your TileEntity from server to client:
@Override
public Packet getDescriptionPacket() {
NBTTagCompound tag = new NBTTagCompound();
this.writeToNBT(tag);
return new Packet132TileEntityData(xCoord, yCoord, zCoord, 1, tag);
}

// combined with this:
@Override
public void onDataPacket(INetworkManager net, Packet132TileEntityData packet) {
readFromNBT(packet.data);
}

From the sounds of it, you are simply missing the synchronization part.

[GotoLink]

Thanks guys, this was just a misunderstanding on my part of how I thought it worked (Java is not my main programming language in my day job), but a question does pop into my head after reading the above, granted I have access to the getter and setter for fields on the TE class so for this instance im good, but if i needed to how do i simply view whats currently in the NBT for the given entity, its something thats always bugged me and something ive not found anyone doing (probably because you wouldnt need it in the final code, debug only)

There is a simple way to read the NBT tags from any tileentity, have an example:

 

NBTTagCompound tags = new NBTTagCompound();
tileentity.writeToNBT(tags);
System.out.println(tags);//debug here

 

You can also use readFromNBT to actually change some data within the tileentity, but it isn't recommended.

[Draco18s]

You can also use readFromNBT to actually change some data within the tileentity, but it isn't recommended.

 

I use that feature to put custom values into a mob spawner placed during world gen, so that it will spawn a custom mob and at a much lower rate than the default.

http://www.minecraftforge.net/wiki/Mob_Spawners

[skullywag]

Thanks everyone, not only is it working perfectly now, but due to me now understanding how this all works now i tidied lots of code up and feel a lot happier about this.

 

The block that is set uses 5 metas to render different stages of its model (it "grows" on update) so had to transfer the nbt "colour" to the new TE on update so it didnt lose its colour when it set the next block meta. other than that turns out this was pretty darnd simple.

 

My only issue now is my models....techne seems to not like rotating things the right way, looks fine in techne, looks totally wrong in game. Dont suppose anyone knows why this is, seems to be an issue with the middleslider, I did find a post for help by who i can only assume is the maintainer of it:

 

http://answers.unity3d.com/questions/375526/techne-y-rotation-bug-minecraft-modeling-program.html

 

think this is the issue im having. Wonder if techne will ever get completed.

[Draco18s]

My only issue now is my models....techne seems to not like rotating things the right way, looks fine in techne, looks totally wrong in game. Dont suppose anyone knows why this is, seems to be an issue with the middleslider, I did find a post for help by who i can only assume is the maintainer of it

 

Probably has to do with the fact that Euler angles suck and quaternions are better.

 

There is probably not anything you can do.

[skullywag]

strangely though changing the rotation on the model class itself doesnt seem to do anything, it seems locked at a certain facing and I cannot change it, that...cannot..be right. I must be seeing things, gonna test further.