I want a crafting recipe to give a smooth stone double slab, but it doesn't have an itemblock.

 

However, I have no idea how to make or register an itemblock for it, because before I have just registered itemblocks in the block itself.

 

So, my question is: How do I create an itemblock for the vanilla smooth double slab?

Is it really important to make the double directly? Isn't it reasonable to make singles and then double them up when placed? I suppose what I am asking is what you are trying to achieve (Why do you want this?)

Is it really important to make the double directly? Isn't it reasonable to make singles and then double them up when placed? I suppose what I am asking is what you are trying to achieve (Why do you want this?)

 

I'm not placing regular double stone slabs, I'm placing smooth double stone slabs, i.e. this: http://lh5.ggpht.com/2xdwbMAyszHT3nxQ7Ozal2hs6O-mqQYOf2UOKYx2nbpv8Ejn75tJGAeRZ8D_CrnVzsCCR8lzan6j0QH_Sy4ssnk=s400-rj-v1-c0xffffff[/img]

That block does not exist as a valid state any more.  It used to only through a quirk of how the metadata value was handled.

 

You will need to fake it.

That block does not exist as a valid state any more.  It used to only through a quirk of how the metadata value was handled.

 

You will need to fake it.

No, it still exists as double_stone_slab, metadata value 8.

It can still be placed with

/setblock 60 63 282 minecraft:double_stone_slab 8

Lets see....

Ahh.  At first I was going to say "well yes, you're forcing the metadata, but it's still not a valid blockstate per the BlockStatecontainer rules (that is, you can't use

world.setBlockState(..)

) but actually it is.  There's two properties involved:

 

Variant (stone, wood, etc) and Seamless.  All double slabs are not seamless by the way the slab item works, but you can set the property.

 

The OP is still going to have to register their own item and model for it, though.