Adds siemens_coefficient handling to stun batons

code/game/objects/items/weapons/stunbaton.dm

@@ -108,12 +108,14 @@
 		return
 
 	var/agony = agonyforce
+	var/stun = stunforce
 	var/mob/living/L = M
 
 	var/contact = 1
 	if(user.a_intent == "harm")
 		contact = ..()
 		agony *= 0.5	//whacking someone causes a much poorer contact than prodding them.
+		stun *= 0.5
 	else
 		//copied from human_defense.dm
 		if (ishuman(L))
@@ -145,14 +147,20 @@
 	if (contact)
 		msg_admin_attack("[key_name(user)] attempted to stun [key_name(L)] with the [src].")
 		
-		if (stunforce)
-			L.Stun(stunforce)
-			L.Weaken(stunforce)
-			L.apply_effect(STUTTER, stunforce)
+		if (ishuman(L))
+			var/mob/living/carbon/human/H = L
+			var/datum/organ/external/affected = get_organ(def_zone)
+			var/siemens_coeff = H.get_siemens_coefficient_organ(affected)
+			stun *= siemens_coeff
+			agony *= siemens_coeff
+		
+		if (stun)
+			L.Stun(stun)
+			L.Weaken(stun)
+			L.apply_effect(STUTTER, stun)
 		
 		if (agony)
-			//Siemens coefficient?
-			//TODO: Merge this with taser effects
+			//perhaps this could be merged with taser effects?
 			L.apply_effect(agony,AGONY,0)
 			L.apply_effect(STUTTER, agony/10)
 			L.apply_effect(EYE_BLUR, agony/10)

code/modules/mob/living/carbon/human/human_defense.dm

@@ -120,6 +120,20 @@ emp_act
 				protection += C.armor[type]
 	return protection
 
+//this proc returns the Siemens coefficient of electrical resistivity for a particular external organ.
+/mob/living/carbon/human/proc/get_siemens_coefficient_organ(var/datum/organ/external/def_zone)
+	if (!def_zone)
+		return 1.0
+	
+	var/siemens_coefficient = 1.0
+	
+	var/list/clothing_items = list(head, wear_mask, wear_suit, w_uniform, gloves, shoes) // What all are we checking?
+	for(var/obj/item/clothing/C in clothing_items)
+		if(istype(C) && (C.body_parts_covered & def_zone.body_part)) // Is that body part being targeted covered?
+			siemens_coefficient *= C.siemens_coefficient
+	
+	return siemens_coefficient
+
 /mob/living/carbon/human/proc/check_head_coverage()
 
 	var/list/body_parts = list(head, wear_mask, wear_suit, w_uniform)