SSTurrets (#3453)

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## About The Pull Request

Defines a small subsystem for turrets that fires every 5 ticks. Allows
us to actually set turret fire rates that aren't bound to SSMachines
will.

Resolves #3407 
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## Why It's Good For The Game
Turret Function :)
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## Changelog

:cl:
fix: Turrets should now actually fire at their defined fire rates. 
/:cl:

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---------

Signed-off-by: Erika Fox <[email protected]>

code/__DEFINES/subsystems.dm

@@ -130,6 +130,7 @@
 #define INIT_ORDER_ATOMS 30
 #define INIT_ORDER_LANGUAGE 25
 #define INIT_ORDER_MACHINES 20
+#define INIT_ORDER_TURRETS 17
 #define INIT_ORDER_SKILLS 15
 #define INIT_ORDER_TIMER 1
 #define INIT_ORDER_DEFAULT 0

code/controllers/subsystem/turrets.dm

@@ -0,0 +1,41 @@
+SUBSYSTEM_DEF(turrets)
+	name = "Turrets"
+	wait = 5
+	init_order = INIT_ORDER_MACHINES
+	flags = SS_KEEP_TIMING
+	runlevels = RUNLEVEL_GAME | RUNLEVEL_POSTGAME
+	var/list/processing = list()
+	var/list/currentrun = list()
+
+/datum/controller/subsystem/turrets/get_metrics()
+	. = ..()
+	var/list/cust = list()
+	cust["processing"] = length(processing)
+	.["custom"] = cust
+
+/datum/controller/subsystem/turrets/stat_entry(msg)
+	msg = "M:[length(processing)]]"
+	return ..()
+
+
+/datum/controller/subsystem/turrets/fire(resumed = 0)
+	if (!resumed)
+		src.currentrun = processing.Copy()
+
+	//cache for sanic speed (lists are references anyways)
+	var/list/currentrun = src.currentrun
+
+	var/seconds = wait * 0.1
+	while(currentrun.len)
+		var/obj/machinery/thing = currentrun[currentrun.len]
+		currentrun.len--
+		if(QDELETED(thing) || thing.process(seconds) == PROCESS_KILL)
+			processing -= thing
+			if (!QDELETED(thing))
+				thing.datum_flags &= ~DF_ISPROCESSING
+		if (MC_TICK_CHECK)
+			return
+
+/datum/controller/subsystem/turrets/Recover()
+	if (istype(SSturrets.processing))
+		processing = SSmachines.processing

code/game/machinery/porta_turret/portable_turret.dm

@@ -41,6 +41,7 @@ DEFINE_BITFIELD(turret_flags, list(
 	integrity_failure = 0.5
 	armor = list("melee" = 50, "bullet" = 30, "laser" = 30, "energy" = 30, "bomb" = 30, "bio" = 0, "rad" = 0, "fire" = 90, "acid" = 90)
 	base_icon_state = "standard"
+	subsystem_type = /datum/controller/subsystem/turrets
 	/// Scan range of the turret for locating targets
 	var/scan_range = 7
 	/// For turrets inside other objects
@@ -77,7 +78,7 @@ DEFINE_BITFIELD(turret_flags, list(
 	var/has_cover = TRUE
 	/// The cover that is covering this turret
 	var/obj/machinery/porta_turret_cover/cover = null
-	/// Ticks until next shot (1.5 ?)
+	/// Ticks until next shot (1.5 ?) If this needs to go below 5, use SSFastProcess
 	var/shot_delay = 15
 	/// Turret flags about who is turret allowed to shoot
 	var/turret_flags = TURRET_FLAG_SHOOT_CRIMINALS | TURRET_FLAG_SHOOT_ANOMALOUS

shiptest.dme

@@ -393,6 +393,7 @@
 #include "code\controllers\subsystem\title.dm"
 #include "code\controllers\subsystem\traumas.dm"
 #include "code\controllers\subsystem\turf_fire.dm"
+#include "code\controllers\subsystem\turrets.dm"
 #include "code\controllers\subsystem\verb_manager.dm"
 #include "code\controllers\subsystem\vis_overlays.dm"
 #include "code\controllers\subsystem\vote.dm"