[1.12] Modifying a Vanilla World Generation Feature

[FilthyNoob]

Hello all -

I'm trying to add a particular world generation feature and I would like some input from the veterans here as to the best way to approach it.

I would like to add to/alter/modify/replace the vanilla WorldGenLakes WorldGenerator so that when a lava lake is generated, a particular ore block is placed nearby. I am interested in, in order of importance:

1) Placing these ore blocks above or immediately adjacent to the edges of the lava lake.

2) Adding this feature to all generated lava lakes

3) Adding this feature in such a way that vanilla generation is otherwise unchanged - that is, for a given seed, the lava lakes would be found in identical places regardless of whether my mod is installed.

4) Respecting the vanilla ChunkGeneratorOverworld settings, particularly lavaLakeChance and useLavaLakes.

I have tried the following approaches:
- I've looked into the PopulateChunkEvent family, but as this event seems to be a gatekeeper only, the event does not give me the ultimate location of the lava lake, only the coordinates of the chunk the feature could be placed in.

- I've tried canceling the aforementioned event and replacing it with my own generator (extending vanilla WorldGenLakes). This gives me access to the position, but I still don't have access to the ChunkGeneratorOverworld settings from the event, effectively changing the position of all vanilla lava lakes (since I don't know how to access lavaLakeChance or useLavaLakes). Furthermore this seems like a brittle approach as if I want the lakes to generate in the same place as vanilla, I will have to copy-paste vanilla code (as the actual feature positioning logic is in ChunkGeneratorOverworld).

- I've tried simply adding a new generator object, but I'm not very satisfied with this approach as it not only creates an overabundance of lava lakes, but creates lava lakes without the ore blocks as vanilla will still be generating.

I'm sure there's something I'm overlooking or missing here, thank you for reading.

[jabelar]

You can intercept when a lake or lava lake is being generated by handling the PopulateChunkEvent.Populate event and checking if the event type is LAKE or LAVA.

[FilthyNoob]

Thank you for the reply.

I've tried that approach, but since I don't know how to access the ChunkGeneratorOverworld settings object, the lakes I generate will be in a different place than in vanilla. The fields lavaLakeChance and useLavaLakes are of particular interest. If I could figure out how to respect vanilla settings this approach would work fine.

[Choonster]

6 hours ago, FilthyNoob said:

Thank you for the reply.

I've tried that approach, but since I don't know how to access the ChunkGeneratorOverworld settings object, the lakes I generate will be in a different place than in vanilla. The fields lavaLakeChance and useLavaLakes are of particular interest. If I could figure out how to respect vanilla settings this approach would work fine.

 

Check if the event's IChunkGenerator is an instance of ChunkGeneratorOverworld, then use reflection to access the ChunkGeneratorOverworld#settings field.

[FilthyNoob]

I had a feeling I would have to learn how to use reflection eventually. I am now looking through the MCP mappings, some tutorials, and doing some small experiments to make sure I understand how it all works.

Thank you for the insight.