Possible bug: Biome samples does an OR operation instead of AND for multiple specified biomes

[dragitz]

Goal is to find an area near world origin, with specified and decently sized biomes near each other, within reasonable distances.

My current settings are:

MC version: 1.21.3

Biome Sample:
[x] Within radial distance: 250

Biomes:
Required coverage (%): 10
Confidence (%): 95
[+] Cherry Grove
[+] Flower Forest
[+] Dark Forest

Possible bug:
Not all desired biomes are currently found in the specified area and, most of the times, it's either one or two that are found out of the 3, which leads me to believe the Biome samples option, does an OR operation instead of AND when checking if the specified biomes are present or not.

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Changing other parameters such as setting Y to 62 (Sea Level), increasing the confidence to 99 or 100 and checking Yield individual samples has little to no notable change in the outcome.

[Jereaux]

Hey dragitz. I'm not 100% certain, but I believe the feature is likely working as intended, and isn't really an "OR" search but more of an "ANY". The condition is looking for 10% coverage of any combination of the selected biomes (much like how the Match Any button works for "overworld at scale" searches). If it achieves 10% coverage of the area with 95% confidence with just Cherry Grove, then it passes, or if it reaches it from 5% Cherry and 5% Flower Forest, that also passes.

Your search could still be accomplished with 3 separate queries, or if you don't care how much of each but want all three you could define a biome search for all three types in an area, and add this condition as well to get sufficient coverage.

While it doesn't quite meet the needs for your type of search, it does work wonders for some search types such as island searches. For example looking for 90% coverage of Any ocean. You could also use it to find large patches of biomes that often are linked to similar parameters like Dark Forest and Pale Garden, or Meadow/Cherry Grove

I could see a feature request to add a checkbox for something like "Match All" (all biomes must be present) or "Match All Separately" (All biomes must be present and each must match the required coverage). Just a thought.

[dragitz]

Hi Jereaux, thanks for the reply.

That makes sense now that you’ve explained it as an "ANY" operation rather than a strict "OR". I can see how it works well for certain types of searches, like ocean or linked biomes, but it does feel a bit limiting for cases like mine where all specified biomes are needed. (a wiki page could help new users a lot!)

Running separate queries or tweaking a combined search could work as a workaround for now, though it's definitely more manual effort. The idea of a "Match All" or "Match All Separately" option sounds like it would bridge this gap perfectly and add a lot of flexibility.

While I still don't fully understand how each feature works under the hood, I found out that instead of using 3 different biome filters, I could use one "Overworld at scale" and it seems to find good ones.

Cheers!