Imo it’s absolutely not acceptable that renoise still records automation in line resolution. It should be high / tick resolution always…
At least while moving sliders by hand or midi.
So for offering this to lua, the api needs some kind of stable called interrupt to which you can register, instead imprecise idle constructions. Do you remember interrupts on amiga?
Agree that the resolution is a pain. A quick user-level workaround is to increase LPB and expand selection/pattern by the LPB increase factor, or increase tempo and use phrases. Atleast AFK, I remember having done this a few times.
Edit: just occurred to me you were asking for recording automation, not inputting, but I guess the same would apply with some interpolation after the fact, but that’s a bit long-winded. Apologies for the misunderstanding.