Doc outlining how batteries are represented in the game

[kevingranade]

Summary

None

Purpose of change

With some recent battery overhauls and discussions around them, it's clear that there's enough confusion that a doc outlining how we handle batteries and power consumption is warranted.

Describe the solution

I sketched out some decisions about how batteries and power are handled and rationales for them.

Describe alternatives you've considered

Not doing so?
I don't think documenting specific items in a centralized doc is particularly helpful because something like "this is expected to be able to run for 4h" fits better in a comment in the item definition itself and maybe in a unit test that verifies it.
I'm sure there's more that could go in here, if people have tips for how to look up or otherwise determine device runtime or power draw that would be good to go in here.
This could also go in some other doc, but I didn't see anywhere I'd expect it to fit at a glance.

[x-qq]

I think a list of requirements for electric devices similar to what was proposed in #76056 (which on its own was inspired by specific useful data sets provided in GAME_BALANCE.md, MELEE_BALANCE_SPREADSHEET.md and other similar documents) would be a good addition that would allow further work to be built directly on this design document.

[GuardianDll]

as told, it would be better to hold it in the item description

[IdleSol]

Is there an example of the calculation?

I haven't looked at the documents very closely. But I didn't see any mention of the batteries being charged in kilo joules. Only found it somewhere in the posts.

The internet told me that watts are joules divided by time. From this it comes out that:

1. Add an instrument that needs to be on (example, mp3 player)
2. Select the existing battery in the game or the capacity of the built-in battery (in kJ).
   { "pocket_type": "MAGAZINE", "rigid": true, "ammo_restriction": { "battery": 40 } },
3. Choose how long it should work under game conditions
   For example, 24 hours or 24x60x60 = 86400 sec.
4. Divide the capacity by the run time in seconds and get the consumption

    /// 40 x 1000 / 86400 = 0.463 W
    "power_draw": "460 mW",