Fixes cases of mobs not seeing pipe vision.

code/modules/mob/living/carbon/alien/humanoid/alien_powers.dm

@@ -255,10 +255,9 @@ Doesn't work on other aliens/AI.*/
 /obj/effect/proc_holder/alien/regurgitate/fire(var/mob/living/carbon/alien/user)
 	if(user.stomach_contents.len)
 		for(var/atom/movable/A in user.stomach_contents)
-			if(A in user.stomach_contents)
-				user.stomach_contents.Remove(A)
-				A.loc = user.loc
-				//Paralyse(10)
+			user.stomach_contents.Remove(A)
+			A.loc = user.loc
+			A.update_pipe_vision()
 		user.visible_message("<span class='alertealien'>[user] hurls out the contents of their stomach!</span>")
 	return
 

code/modules/mob/living/login.dm

@@ -10,7 +10,10 @@
 			if("sandbox")
 				CanBuild()
 
+	//Vents
 	if(ventcrawler)
 		src << "<span class='notice'>You can ventcrawl! Use alt+click on vents to quickly travel about the station.</span>"
+		update_pipe_vision()
+
 	update_interface()
 	return .

code/modules/mob/living/ventcrawling.dm

@@ -47,9 +47,9 @@ var/list/ventcrawl_machinery = list(/obj/machinery/atmospherics/unary/vent_pump,
 				for(var/obj/item/I in contents)
 					var/failed = 0
 					if(istype(I, /obj/item/weapon/implant))
-						var/obj/item/weapon/implant/imp = I
-						if(imp.imp_in != src)
-							failed++
+						continue
+					else
+						failed++
 
 					if(failed)
 						src << "<span class='warning'>You can't crawl around in the ventilation ducts with items!</span>"
@@ -80,4 +80,18 @@ var/list/ventcrawl_machinery = list(/obj/machinery/atmospherics/unary/vent_pump,
 	pipes_shown.len = 0
 
 	if(client)
-		client.eye = src
+		client.eye = src
+
+
+
+//OOP
+/atom/proc/update_pipe_vision()
+	return
+
+/mob/living/update_pipe_vision()
+	if(pipes_shown.len)
+		if(!istype(loc, /obj/machinery/atmospherics))
+			remove_ventcrawl()
+	else
+		if(istype(loc, /obj/machinery/atmospherics))
+			add_ventcrawl(loc)

code/modules/mob/transform_procs.dm

@@ -78,6 +78,8 @@
 	if (tr_flags & TR_DEFAULTMSG)
 		O << "<B>You are now a monkey.</B>"
 
+	O.update_pipe_vision()
+
 	for(var/A in loc.vars)
 		if(loc.vars[A] == src)
 			loc.vars[A] = O
@@ -191,6 +193,8 @@
 	if (tr_flags & TR_DEFAULTMSG)
 		O << "<B>You are now a human.</B>"
 
+	O.update_pipe_vision()
+
 	updateappearance(O)
 	. = O
 
@@ -238,6 +242,8 @@
 	else
 		O.key = key
 
+	O.update_pipe_vision()
+
 	var/obj/loc_landmark
 	for(var/obj/effect/landmark/start/sloc in landmarks_list)
 		if (sloc.name != "AI")
@@ -322,6 +328,8 @@
 	else
 		O.key = key
 
+	O.update_pipe_vision()
+
 	O.loc = loc
 	O.job = "Cyborg"
 	O.notify_ai(1)
@@ -357,6 +365,7 @@
 	new_xeno.key = key
 
 	new_xeno << "<B>You are now an alien.</B>"
+	new_xeno.update_pipe_vision()
 	. = new_xeno
 	qdel(src)
 
@@ -389,6 +398,7 @@
 	new_slime.key = key
 
 	new_slime << "<B>You are now a slime. Skreee!</B>"
+	new_slime.update_pipe_vision()
 	. = new_slime
 	qdel(src)
 
@@ -425,6 +435,7 @@
 	new_corgi.key = key
 
 	new_corgi << "<B>You are now a Corgi. Yap Yap!</B>"
+	new_corgi.update_pipe_vision()
 	. = new_corgi
 	qdel(src)
 
@@ -458,6 +469,7 @@
 
 
 	new_mob << "You suddenly feel more... animalistic."
+	new_mob.update_pipe_vision()
 	. = new_mob
 	qdel(src)
 
@@ -475,6 +487,7 @@
 	new_mob.key = key
 	new_mob.a_intent = "harm"
 	new_mob << "You feel more... animalistic"
+	new_mob.update_pipe_vision()
 
 	. = new_mob
 	qdel(src)