How to register and generate jigsaw structures in 1.16.3+ Minecraft Forge using nbt files!
Change the Github branch to see other versions of this tutorial including for Fabric!
This very small Forge mod is full of comments that will help you understand what a lot of the methods do and what needs to be done to get your structure to generate. In all, this mod is really just 4 java files, 2 JSON files, and 3 structure nbt files.
If you don't know how to make a nbt file for structures, it's actually fairly simple and you can do it all inside minecraft itself! Here is a video on how to make and save a structure to nbt using structure blocks. Here's a short video on how Structure Blocks work:
If your structure is only a single piece, then you do NOT need any Jigsaw Blocks and can just use 1 pool file. If you want your jigsaw structure to have more than 1 piece, you will need to setup and save Jigsaw blocks into your structure's nbt files. The Jigsaw blocks acts as connectors between the nbt pieces and pool files. (Here's two videos about using Jigsaw Blocks in structures! The first one is very long but extremely detailed.):
Handy image for a shorthand way of how Jigsaw Blocks and Pools work together:
Once saved, the structure nbt file is stored in that world's save folder within the generated folder inside. Grab those files as you'll need to put it under your mod's resource folder inside data/mod_id/structures. NOTICE: This the data folder and not the asset folder inside resource! Then make a JSON file and put it in data/mod_id/worldgen/template_pool folder. Take a look at this tutorial's start_pool.json file for how to setup the JSON file itself.
Now you're ready to begin adding the structure to your mod! Take a look at StructureTutorialMain, start reading the comments, and follow the methods/classes. Don't just copy the code quickly or else you will get confuse. Take your time and try to understand how it all works before attempting to register and generate your structure in your own mod. (Also, check out the house structure itself in the world! There's some info on signs in the structure itself about nbt files)
When making your own mod, make sure to include the accesstransformer file and to include it in your build.gradle. If your IDE still say that the methods listed in the access transformer are private and shows an error, then you may need to refresh gradle and generate the runs again so the accesstransformers takes effect.
Also, if you get stuck on the template_pool json, here's a datapack of the entire vanilla worldgen. Including vanilla's template_pools. Use this if you want to see how vanilla setup their pools! https://github.com/TelepathicGrunt/StructureTutorialMod/releases/tag/0.0.0
Good luck and I hope this helps!
You can contact me through issue reports here or on discord. My Discord is TelepathicGrunt#7397 and my channel is: https://discord.gg/SM7WBT6FGu
MCPBot is dead. Do not use that to check for updates.
if you want the absolute latest mapping, run gradlew -PUPDATE_MAPPINGS=1.16.5 -PUPDATE_MAPPINGS_CHANNEL=official updateMappings
command for the project and it'll remap everything to the cutting-edge mappings! Then change the mappings line in your
build.gradle to mappings channel:"official", version:"1.16.5"