So, trying to make some pipes.

Well it works great! You just can't go west.

If you go west, 1000 becomes some random negative value. Hmmm.

@Override
public int fill(ForgeDirection from, FluidStack resource, boolean doFill)
{

	if (worldObj.getTileEntity(xCoord + 1, yCoord, zCoord)  instanceof TileEntityLiquid && from != ForgeDirection.EAST && worldObj.getTileEntity(xCoord + 1, yCoord, zCoord) != null) 
	{
		((TileEntityLiquid) worldObj.getTileEntity(xCoord + 1, yCoord, zCoord)).fill(ForgeDirection.WEST, resource.copy(), doFill);
	}
	if (worldObj.getTileEntity(xCoord - 1, yCoord, zCoord)  instanceof TileEntityLiquid && from != ForgeDirection.WEST && worldObj.getTileEntity(xCoord - 1, yCoord, zCoord) != null) 
	{
		((TileEntityLiquid) worldObj.getTileEntity(xCoord - 1, yCoord, zCoord)).fill(ForgeDirection.EAST, resource.copy(), doFill);
	}
	if (worldObj.getTileEntity(xCoord, yCoord + 1, zCoord)  instanceof TileEntityLiquid && from != ForgeDirection.UP && worldObj.getTileEntity(xCoord, yCoord + 1, zCoord) != null) 
	{
		((TileEntityLiquid) worldObj.getTileEntity(xCoord, yCoord + 1, zCoord)).fill(ForgeDirection.DOWN, resource.copy(), doFill);
	}
	if (worldObj.getTileEntity(xCoord, yCoord - 1, zCoord)  instanceof TileEntityLiquid && from != ForgeDirection.DOWN && worldObj.getTileEntity(xCoord, yCoord - 1, zCoord) != null) 
	{
		((TileEntityLiquid) worldObj.getTileEntity(xCoord, yCoord - 1, zCoord)).fill(ForgeDirection.UP, resource.copy(), doFill);
	}
	if (worldObj.getTileEntity(xCoord, yCoord, zCoord + 1)  instanceof TileEntityLiquid && from != ForgeDirection.SOUTH && worldObj.getTileEntity(xCoord, yCoord, zCoord + 1) != null) 
	{
		((TileEntityLiquid) worldObj.getTileEntity(xCoord, yCoord, zCoord + 1)).fill(ForgeDirection.NORTH, resource.copy(), doFill);
	}
	if (worldObj.getTileEntity(xCoord, yCoord, zCoord - 1) instanceof TileEntityLiquid && from != ForgeDirection.NORTH && worldObj.getTileEntity(xCoord, yCoord, zCoord - 1) != null) 
	{
		((TileEntityLiquid) worldObj.getTileEntity(xCoord, yCoord, zCoord - 1)).fill(ForgeDirection.SOUTH, resource.copy(), doFill);
	}
	return tank.fill(resource, doFill);

}

clarification, each pipe has it's own tank, but they are all symbolic to the "network tank."

Basically, if theres 1000 buckets in the network, each pipe has 1000 buckets in it's tank.

Fill and drain commands are networked across all pipes. Draw 1 mB from 1 pipe, all pipes go down 1 mB.

Any help?

How do you know '1000 becomes some random negative value'? Show us how you debugged that, it may help us.

 

Also,

instanceof

already does

null

checks, so you can remove those

getTileEntity() != null

calls.

The pipe block has this code:

 @Override
    public boolean onBlockActivated(World world, int x, int y, int z, EntityPlayer player, int par5, float par6, float par7, float par8)
    {
    	if(!world.isRemote)
    	{
    		TileEntity tile = world.getTileEntity(x, y, z);
    		if(tile instanceof TileEntityLiquid)
    		{
    			player.addChatMessage(new ChatComponentText("Network is holding " + ((TileEntityLiquid)tile).getTankInfo(ForgeDirection.UNKNOWN)[0].fluid.amount));
    			return true;
    		}
    		return false;
    	}
    	return false;
    }

[CHAT] Network is holding -1540044424
[16:21:19] [Client thread/INFO]: [CHAT] Network is holding -1540044424
[16:21:19] [Client thread/INFO]: [CHAT] Network is holding -403279352
[16:21:20] [Client thread/INFO]: [CHAT] Network is holding -171803008

I ended up replacing the code with the east code and changed a few values.

It's fixed now.

Btw you code doesn't need to be as complex. The ForgeDirection class has XYZ offset values and it also has a getOpposite() property.

 

The following would work on any side sent (You may want to check for the UNKNOWN side):

((TileEntityLiquid) worldObj.getTileEntity(xCoord + from.offsetX, yCoord + from.offsetY, zCoord + from.offsetZ)).fill(from.getOpposite(), resource.copy(), doFill);