Furnace callback

[rbdyck]

Every time I've asked for something, you've pointed out I can do it with existing features. Fine, using existing features is preferable. I only come here after I've exhausted everything. This time I don't think there's an easy alternative, but if you know one then please be gentle.

 

I need a call-back for the furnace. My mod requires smelting ore produces an effect: certain ores produce toxic gas. What I did was replace the furnace with a new one that extends BlockFurnace. It has exactly the same texture, exactly the same functions. It works exactly the same, except the gas. To do this and keep it general, I wrote an interface. The new furnace implements that interface. This also simplifies interaction between Block and TileEntity, so the TileEntity doesn't have to hard-code the Block that creates it.

 

Interface

 

import net.minecraft.item.Item;

import net.minecraft.world.World;

 

public interface CallbackFurnace

{

    public void updateFurnace(boolean isActive, World world, int x, int y, int z);

    public void onInventoryChanged(boolean isBurning, Item ore, World world, int x, int y, int z);

}

 

 

Block

 

public class BlockGasFurnace extends BlockFurnace implements CallbackFurnace

{

    private static CallbackFurnace callbackCommand = null;

 

    public static void updateFurnaceBlockState(boolean isActive, World world, int x, int y, int z)

    {

        int metadata = world.getBlockMetadata(x, y, z);

        TileEntity tileEntity = world.getBlockTileEntity(x, y, z);

        keepFurnaceInventory = true;

 

        if (isActive)

        {

            world.setBlock(x, y, z, MyMod.gasFurnaceActive.blockID);

        }

        else

        {

            world.setBlock(x, y, z, MyMod.gasFurnaceIdle.blockID);

        }

 

        keepFurnaceInventory = false;

        world.setBlockMetadataWithNotify(x, y, z, metadata, 2);

 

        if (tileEntity != null)

        {

            tileEntity.validate();

            world.setBlockTileEntity(x, y, z, tileEntity);

        }

 

        if (callbackCommand != null)

        {

            callbackCommand.updateFurnace(isActive, world, x, y, z);

        }

    }

 

    @Override

    public TileEntity createNewTileEntity(World world)

    {

        TileEntityGasFurnace tileEntity = new TileEntityGasFurnace();

        tileEntity.setCallback(this);

        return tileEntity;

    }

 

    @Override

    public void updateFurnace(boolean isActive, World world, int x, int y, int z)

    {

        this.updateFurnaceBlockState(isActive, world, x, y, z);

    }

 

    public void onInventoryChanged(boolean isBurning, Item ore, World world, int x, int y, int z)

    {

        if (callbackCommand != null)

        {

            callbackCommand.onInventoryChanged(isBurning, ore, world, x, y, z);

        }

    }

 

    public void setCallback(CallbackFurnace callback)

    {

        callbackCommand = callback;

    }

}

 

 

TileEntity

 

import net.minecraft.tileentity.TileEntityFurnace;

import net.minecraft.item.Item;

import net.minecraft.item.ItemStack;

import net.minecraft.item.crafting.FurnaceRecipes;

import net.minecraft.nbt.NBTTagCompound;

import net.minecraft.nbt.NBTTagList;

 

public class TileEntityGasFurnace extends TileEntityFurnace

{

    private static CallbackFurnace callbackCommand = null;

 

    @Override

    public void updateEntity()

    {

        boolean flag = this.furnaceBurnTime > 0;

        boolean inventoryChanged = false;

        boolean cookingChanged = false;

        ...

        if (flag != this.furnaceBurnTime > 0)

        {

            inventoryChanged = true;

            cookingChanged = true;

 

            if (callbackCommand != null)

            {

                callbackCommand.updateFurnace(this.furnaceBurnTime > 0, this.worldObj, this.xCoord, this.yCoord, this.zCoord);

            }

        }

 

        if (inventoryChanged)

        {

            this.onInventoryChanged();

        }

 

        if (cookingChanged)

        {

            if (callbackCommand != null)

            {

                Item ore = null;

 

                if (this.furnaceItemStacks[0] != null)

                {

                    ore = this.furnaceItemStacks[0].getItem();

                }

 

                callbackCommand.onInventoryChanged(this.isBurning(), ore, this.worldObj, this.xCoord, this.yCoord, this.zCoord);

            }

        }

    }

 

    public void setCallback(CallbackFurnace callback)

    {

        callbackCommand = callback;

    }

}

 

 

Mod

 

public class MyMod implements CallbackFurnace

{

    public void updateFurnace(boolean isActive, World world, int x, int y, int z) {}

    public void onInventoryChanged(boolean isBurning, Item ore, World world, int x, int y, int z)

    {

        /* what to do when inventory changes */

    }

}

 

 

I've found the CallbackFurnace interface very useful. But the key thing is BlockFurnace itself. To call a method in my mod when inventory changes. Also, I had to copy significant code for TileEntity due to private variables.

 

What I've done works. But the issue is replacing the furnace with a new block creates a new BlockID. This is only a problem when another mod wants to use the furnace as an ingredient for crafting. It creates an incompatibility. I have a few users asking for a resolution. A hook when inventory changes would resolve it.

 

Thanks

[LexManos]

1) Your issue could be solved by simply making your new furnace replace the old one directly, using the same ID

2) Your callback is hardcoded to a single listener, this is not good. You should look into firing off an event instead of a singular callback.

3) You could just override the onInventoryChanged function in TileEntity and get the same information....

 

Not really seeing anything that is necessary for base class edits.

 

[rbdyck]

My understanding is overriding a block ID with the same ID causes Minecraft to crash.

[LexManos]

Not if you do it correctly. Go do some research see if you can figure it out.