Sub-Biomes Help - Advanced Questions

Hello,

Minecraft: 1.12.2

Basically, is there anyway to add a sub biome type for a modded biome, similar to how vanilla does it? (example: ExtremeHills: has ExtremeHills+ and ExtremeHills M, Forest: has ForestHills and ForestM(flower forest) )

So for my example: I have an exotic jungle biome, i'd love to add an edge, hills and mountain variant of them and have them as weighted sub-biomes that generate only when my Exotic Jungle spawns, this would add variation to my biomes.

Is there a way to do this in the default worldtype? 

I don't want to create my own worldtype or dimension, I want them naturally spawning in the overworld.

However, from my research, it seems I need to create my own GenLayer as that is where all the code for this subbiome stuff is registered and located but I have no idea how to create my own Genlayer that works side by side or overwrites the original or how to get it registered in my mods initialisation, so is there any forge command or way to add and create a custom genlayer or simply a way to add subbiomes naturally without doing so?

I've also tried the command .setbasebiome when setting up my biomes and that doesn't work either.

Basically, I just want to know if its possible to do without a major overhaul to the world generation code? because if there isn't, i'll just give-up adding that level of depth to my biomes! haha

Funnily enough, upon googling custom genlayer, I actually discovered a topic on the minecraft forum from 4 years ago with me asking the same thing when I first got into modding for 1.4.7! 

Edited January 11, 20196 yr by Zathrox
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