Factorio Forums

I propose an idea of allowing assembling machines to have a result which is not a whole item, but gets added "progress" to it on each craft, like rocket silo works for assembling a rocket (if this was changed in SA I forgot). One use case I can see even in vanilla is Uranium Processing: instead of a chance for either U-238 or U-235 you can get a U-238 item and fill a progress meter towards getting a piece of U-235. This would make the recipe deterministic, and based on the existence of mods such as Deterministic Uranium Enrichment this is something some players might appreciate.

Benefits:

• More flexibility for modders
• Allows "less than one" recipe outputs without having to multiply ingredient and result amount to make the recipe deterministic

Downsides:

• The progress is lost when a machine is mined/destroyed or removed in any other way
• The progress is not shared between assembling machines and there is no way to transfer it from one machine to another

The probabilistic approach like in Uranium Processing in the base game doesn't have the listed downsides, but only has a guarantee of the real output being statistically identical to intended due to many "samples", relying on randomness. That might make a significant difference for something like Uranium Processing, where players usually collect a certain amount of U-235 items until they can begin the enrichment process. And even then the enrichment process could also make use of this mechanic, although I doubt it would be the intended way kovarex enrichment works.