Hey all. I'm trying to figure out this id-shifting thing, and after scouring the net & forums I think I've got it, I just want to check here to make sure. Previously I thought that block ids could range from 1-4096, and items could range from 1-31743, and that the ids for blocks & items were kept separate, meaning a block could have id 4000, and an item could have the same id. I now understand that's wrong. It used to work, b/c I didn't know about the id shifting. So here's how I have it figured, and I think I have it right:

 

First, blocks are stuck using ids 4096 and below, with 1-255 being used for worldgen. Items can use any id up to 31743, though they should begin at 4097 to leave the lower ids for the blocks.  The game adds 256 to the item (not blocks) ids defined in the config files, and it leaves the blocks alone - this is a throwback from older versions of MC when blocks could only be from 1-255, so the shifting was done to keep the first 255 ids open for blocks.

 

Technically, ids can have a shifted id up to 31999, so to use the 4097-31999 id range, items can be defined in their configs from 3842-31743, and blocks from 1-4096, and there will be no conflicts.   

 

I only see one mod so far that doesn't jive with this, and that's the Extra Bees addon for Forestry. In that config, there are 2 blocks, liquid and liquid container, that are given 8500 & 8510 as ids, but the game adds 256 to both of those, so I'm guessing those are actually items that are defined as blocks in the config by mistake.

 

Do I finally have all this right? I use a buttload of mods, and I manually assign ids to all of them in their configs (keeping it all straight on a spreadsheet), so it's imperative I figure this out.

 

A big thanks to whomever reads all that and responds!

 

 

 

That sounds like the jist of it yes.

Great.  Thanks for taking time out to read all that.