Include Fluids in Selector Combinator Stack Size Mode

[dragon-architect]

TL;DR:

When the Selector Combinator is set to Stack Size mode, it should include fluid signals in its output with a stack size of 1 for each.

What?

The Stack Size mode of the Selector Combinator currently only outputs the stack size for items that can be stored in dry storage containers. While fluids technically are not stackable, they are not purely virtual circuit signals either, as the fluid circuit signals represent actual physical things in the world. I propose that the Stack Size mode should pass fluid signals with a stack size of 1.

Why?

I'm in the process of developing my own "Vanilla LTN" system and I've encountered a mildly complicating issue wherein I'm using the Selector Combinator as part of a signal filter chain that whittles the complete set of control and configuration signals down to only the requested resources at requester stations, and the Selector Combinator only passes the signals of stackable items--fluids not included.

I think it would be worthwhile for the Selector Combinator to pass fluid signals with a stack size of 1, since fluids are physical things in the game world--not virtual signals--and this would make the Selector Combinator very useful as a sort of signal filter for only physical items and substances, while blocking all purely virtual signals. Fluids are not stackable, but they are still substances that the player must interact with and handle, and complex circuits that intermix virtual signals with item signals have a need for useful signal filters--especially if the circuits are designed to be generic and agnostic of item/substance input signals.

[Khazul]

That might break a bunch of existing builds - ie people who have already starting using this to check if something is a fluid or not which is really handly when dealing with recipe switching via signals in production machines that support fluids as it easily allows exclusion from requesters and is an easy test to check is pumps needs to be activated etc. Yes I know that exlcusing from requesters isnt essential, but still knowing it is a fluid is very useful.

I vote hard no as-stated as some of my stuff would be broken by it unless the selector undergoes other compensating changes. Sorry.

Many items also have a stack size of 1, so that would remove any way to differentiate items from fluids other than via manually sticking everything in combinators and we have a lot of products now and already I am having to do that way too much to implement function that I think should have been be in the selector combinator from day one.

I would however welcome the concept you suggest, just not breaking this function unless current behaviour were to be replaced by an equivalent check for is fluid.

I often have to exclude specific letter/digit etc signals and it does become a pain when you have to do it for several, for eg to exclude working and finished from production machine that are also reading ingredients as that needs to be cleaned up before checking against inventory/network.

As far as the selector goes, I do think it should have is-item test and an is-recipe test and is-fluid test and conversion functions of product+machine to recipe and recipe to product now that we have several recipes that are not the item in space age and implementing translation tables is a cumbersome pain when you have to do it loads of times in a build.

Given how that zero is also not s signal in factorio, explicit test would be much more useful than the current stack size behaviour with fluids particular when dealing with everything/anything/each.

[boskid]

No. Fluids are not items and stack size is only defined for items.