power monitor sprite (#14331)

code/modules/power/power_monitor.dm

@@ -4,15 +4,19 @@
 	name = "power monitoring computer"
 	desc = "It monitors power levels across the station."
 	icon = 'icons/obj/machines/computer.dmi'
-	icon_state = "power"
-
+	icon_state = "computer"
 	//computer stuff
 	density = TRUE
 	anchored = TRUE
 	circuit = /obj/item/circuitboard/computer/powermonitor
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 300
 	active_power_usage = 300
+	light_range = 1
+	light_power = 0.5
+	light_color = LIGHT_COLOR_EMISSIVE_YELLOW
+	///screen overlay icon
+	var/screen_overlay = "power"
 
 /obj/machinery/power/monitor/core
 	name = "Core Power Monitoring"
@@ -28,6 +32,7 @@
 		attached = locate() in T
 	if(attached)
 		powernet = attached.powernet
+	update_icon()
 
 
 /obj/machinery/power/monitor/interact(mob/user)
@@ -74,16 +79,28 @@
 	popup.open(FALSE)
 	onclose(user, "powcomp")
 
-
 /obj/machinery/power/monitor/update_icon()
-	if(machine_stat & BROKEN)
-		icon_state = "broken"
+	. = ..()
+	if(machine_stat & (BROKEN|DISABLED|NOPOWER))
+		set_light(0)
 	else
-		if(machine_stat & NOPOWER)
-			icon_state = "power0"
-		else
-			icon_state = initial(icon_state)
+		set_light(initial(light_range))
+
+/obj/machinery/power/monitor/update_icon_state()
+	if(machine_stat & (BROKEN|DISABLED))
+		icon_state = "[initial(icon_state)]_broken"
+	else
+		icon_state = initial(icon_state)
+
 
+/obj/machinery/power/monitor/update_overlays()
+	. = ..()
+	if(!screen_overlay)
+		return
+	if(machine_stat & (BROKEN|DISABLED|NOPOWER))
+		return
+	. += emissive_appearance(icon, screen_overlay, alpha = src.alpha)
+	. += mutable_appearance(icon, screen_overlay, alpha = src.alpha)
 
 //copied from computer.dm
 /obj/machinery/power/monitor/attackby(obj/item/I, mob/user, params)