[boskid][2.1.9] "Set recipe" via item signal can't select recipe above normal whose product has quality_change
Posted: Sat Jul 11, 2026 10:43 pm
When a recipe's product has a nonzero `quality_change`, using the circuit "Set recipe" control with that item's signal only works at normal quality. At uncommon and above, the machine is left with no recipe set.
Version: 2.1.9 (build 86829, win64, steam, space-age)
Minimal repro mod attached (qc-setrecipe-repro). It adds two items + two recipes:
- qc-control = {type="item", name="qc-control", amount=1}
- qc-offset = {type="item", name="qc-offset", amount=1, quality_change=-1}
Steps to reproduce (save "bug_repro" attached, already set up):
- Place assembling machine and constant combinator, connect with wire
- Set constant combinator to output qc-offset (or equivalent recipe with `quality_change`) with quality > normal
- Set assembling machine "Set recipe" checkbox
Expected: the qc-offset item signal should select the recipe at higher qualities, the same way the qc-control signal does. The presence of a product `quality_change` should not make a recipe unselectable via item signal. At minimum, silently setting no recipe (with no feedback) is surprising and indistinguishable from "item has no recipe".
Note that the recipe is still craftable at those qualities normally (i.e. I can set the assembly machine's recipe manually still) - only recipe selection by signal fails. Found this playtesting the Maraxsis mod where this happens for the glass recipe:
An LLM made the repro mod.
Version: 2.1.9 (build 86829, win64, steam, space-age)
Minimal repro mod attached (qc-setrecipe-repro). It adds two items + two recipes:
- qc-control = {type="item", name="qc-control", amount=1}
- qc-offset = {type="item", name="qc-offset", amount=1, quality_change=-1}
Steps to reproduce (save "bug_repro" attached, already set up):
- Place assembling machine and constant combinator, connect with wire
- Set constant combinator to output qc-offset (or equivalent recipe with `quality_change`) with quality > normal
- Set assembling machine "Set recipe" checkbox
Expected: the qc-offset item signal should select the recipe at higher qualities, the same way the qc-control signal does. The presence of a product `quality_change` should not make a recipe unselectable via item signal. At minimum, silently setting no recipe (with no feedback) is surprising and indistinguishable from "item has no recipe".
Note that the recipe is still craftable at those qualities normally (i.e. I can set the assembly machine's recipe manually still) - only recipe selection by signal fails. Found this playtesting the Maraxsis mod where this happens for the glass recipe:
- 07-11-2026, 15-41-39.png (1.2 MiB) Viewed 323 times