Quality value formulation.

[DemonicLaxatives]

EffectValue as well as ModuleEffectValue page states:
Quality values are divided by 10 internally, allowing for one more decimal of precision.

However I find this to be incorrect in the general case, as the divisor 10 actually appears to be the base game value for of next_probability that is 0.1 for all qualities.

07-15-2025, 23-30-53.png (54.86 KiB) Viewed 152 times

Here is an unmodified T1 quality module with the next_probability values changed, 0.01 for normal and 0.5 for uncommon
Tooltip indicates that each quality module actually has a separate effect value for each quality step.

I also found this thread where the current formulation was formed: viewtopic.php?p=648446&hilit=quality#p648446

I believe the following pages should be updated to reflect the interaction between them:
https://lua-api.factorio.com/latest/typ ... Value.html
https://lua-api.factorio.com/latest/con ... Value.html
https://lua-api.factorio.com/latest/pro ... robability

[Bilka]

Thank you very much for pointing this out, fixed the docs for 2.0.61.