[2.1.17] Quality Transfer Behavior Inconsistent depending on which signal is set to select from

[knightelite]

When I use a selector combinator with "select from signal" set, and "target signal" set to the same value, in some cases it works as expected (quality is transferred to the output) and in some cases it does not (no output from combinator), even though the combinators are configured identically with the exception of the signal chosen.

Working example (toolbelt):

09-14-2026, 08-02-55.png (1.53 MiB) Viewed 112 times

Broken example (exoskeleton):

09-14-2026, 08-03-33.png (1015.66 KiB) Viewed 112 times

Replication blueprint string below. Just put some items of various qualities into the chests to observe this behavior.

Code: Select all

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

EDIT: I figured out the difference. In the working example, there are normal quality items in the chest, in the non-working one there are not. Still seems unintuitive if you must have the normal signal be present for quality transfer to work, as "select from" should will find the higher quality versions.
Example showing fix:

09-14-2026, 08-07-33.png (1.69 MiB) Viewed 107 times

[Bilka]

It outputs the target signal with the specified quality and its original value. If no normal quality item is in the chest then the normal quality input signal has a value of 0, so the output signal also has a value of 0. You have to supply some value on the target signal if you want a non-zero output of it. Not a bug.