Blindspot Quirk (Yet Another Overlay Quirk)

code/_onclick/hud/fullscreen.dm

@@ -14,7 +14,7 @@
 	if (client && screen.should_show_to(src))
 		screen.update_for_view(client.view)
 		client.screen += screen
-	
+
 	if(screen.needs_offsetting)
 		SET_PLANE_EXPLICIT(screen, PLANE_TO_TRUE(screen.plane), src)
 
@@ -241,3 +241,9 @@
 	icon_state = "blue_eye"
 	plane = FULLSCREEN_PLANE
 	layer = CURSE_LAYER
+
+/// Blindspot quirk - has 4 directions
+/atom/movable/screen/fullscreen/blindspot
+	icon_state = "blindspot"
+	plane = FULLSCREEN_PLANE
+	layer = BLIND_LAYER

code/datums/traits/negative.dm

@@ -678,7 +678,7 @@
 	gain_text = span_danger("You remember your allergic reaction to a common medicine.")
 	lose_text = span_notice("You no longer are allergic to medicine.")
 
-	var/allergy_chem_list = list(	
+	var/allergy_chem_list = list(
 		/datum/reagent/medicine/inacusiate,
 		/datum/reagent/medicine/silver_sulfadiazine,
 		/datum/reagent/medicine/styptic_powder,
@@ -707,7 +707,7 @@
 	var/reagent_id
 	COOLDOWN_DECLARE(allergies)
 	/// how long allergies last after getting rid of the allergen
-	var/cooldown_duration = 10 SECONDS 
+	var/cooldown_duration = 10 SECONDS
 	/// Wether the person is experiencing anaphylatic shock or not
 	COOLDOWN_DECLARE(anaphylaxis)
 	/// How long anaphylactic shock lasts
@@ -751,7 +751,7 @@
 
 	else if(!COOLDOWN_FINISHED(src, allergies)) //if the cooldown is going
 		//external indicator that it's happening
-		if(prob(50)) 
+		if(prob(50))
 			switch(rand(0, 2))
 				if(0)
 					H.emote("cough")
@@ -1017,3 +1017,65 @@
 
 /datum/quirk/lactose_intolerance/proc/on_species_gain(datum/source, datum/species/new_species)
 	new_species.toxic_food |= DAIRY // no escape from your terrible fate
+
+/datum/quirk/blindspot
+	name = "Blindspot"
+	desc = "You lack the sixth sense and cannot see behind yourself."
+	icon = "arrows-to-eye"
+	gain_text = span_danger("You can't see behind yourself anymore.")
+	lose_text = span_notice("You can see behind yourself again.")
+	value = -2
+	medical_record_text = "Patient has trouble with spatial awareness."
+
+#define BLINDSPOT_NORTH "blindspotN"
+#define BLINDSPOT_SOUTH "blindspotS"
+#define BLINDSPOT_EAST "blindspotE"
+#define BLINDSPOT_WEST "blindspotW"
+
+/datum/quirk/blindspot/add()
+	quirk_holder.blindspot_overlay = new/list(10)
+	var/atom/movable/screen/fullscreen/blindspot/north_blindspot = quirk_holder.overlay_fullscreen(BLINDSPOT_NORTH, /atom/movable/screen/fullscreen/blindspot)
+	var/atom/movable/screen/fullscreen/blindspot/south_blindspot = quirk_holder.overlay_fullscreen(BLINDSPOT_SOUTH, /atom/movable/screen/fullscreen/blindspot)
+	var/atom/movable/screen/fullscreen/blindspot/east_blindspot = quirk_holder.overlay_fullscreen(BLINDSPOT_EAST, /atom/movable/screen/fullscreen/blindspot)
+	var/atom/movable/screen/fullscreen/blindspot/west_blindspot = quirk_holder.overlay_fullscreen(BLINDSPOT_WEST, /atom/movable/screen/fullscreen/blindspot)
+	quirk_holder.blindspot_overlay[NORTH] = WEAKREF(north_blindspot)
+	quirk_holder.blindspot_overlay[SOUTH] = WEAKREF(south_blindspot)
+	quirk_holder.blindspot_overlay[EAST] = WEAKREF(east_blindspot)
+	quirk_holder.blindspot_overlay[WEST] = WEAKREF(west_blindspot)
+	north_blindspot.dir = NORTH
+	south_blindspot.dir = SOUTH
+	east_blindspot.dir = EAST
+	west_blindspot.dir = WEST
+	north_blindspot.alpha = (quirk_holder.dir == NORTH) * 255
+	south_blindspot.alpha = (quirk_holder.dir == SOUTH) * 255
+	east_blindspot.alpha = (quirk_holder.dir == EAST) * 255
+	west_blindspot.alpha = (quirk_holder.dir == WEST) * 255
+	RegisterSignal(quirk_holder, COMSIG_ATOM_DIR_CHANGE, PROC_REF(change_dir))
+
+/datum/quirk/blindspot/remove()
+	quirk_holder.clear_fullscreen(BLINDSPOT_NORTH)
+	quirk_holder.clear_fullscreen(BLINDSPOT_SOUTH)
+	quirk_holder.clear_fullscreen(BLINDSPOT_EAST)
+	quirk_holder.clear_fullscreen(BLINDSPOT_WEST)
+	quirk_holder.blindspot_overlay = null
+	UnregisterSignal(quirk_holder, COMSIG_ATOM_DIR_CHANGE)
+
+/datum/quirk/blindspot/proc/change_dir(atom/movable/source, olddir, newdir)
+	SIGNAL_HANDLER
+	if(olddir == 0 || newdir == 0)
+		return
+	if(olddir == newdir)
+		return
+	if(!quirk_holder.blindspot_overlay)
+		return
+	var/atom/movable/screen/fullscreen/blindspot/old_spot = quirk_holder.blindspot_overlay[olddir]?.resolve()
+	var/atom/movable/screen/fullscreen/blindspot/new_spot = quirk_holder.blindspot_overlay[newdir]?.resolve()
+	if(!istype(old_spot) || !istype(new_spot))
+		return
+	animate(old_spot, 0.5 SECONDS, easing = CIRCULAR_EASING|EASE_IN, alpha = 0)
+	animate(new_spot, 0.5 SECONDS, easing = CIRCULAR_EASING|EASE_OUT, alpha = 255)
+
+#undef BLINDSPOT_NORTH
+#undef BLINDSPOT_SOUTH
+#undef BLINDSPOT_EAST
+#undef BLINDSPOT_WEST

code/modules/mob/mob_defines.dm

@@ -249,6 +249,9 @@
 	///Contains the fullscreen overlays the mob can see (from 'code/_onclick/hud/fullscreen.dm')
 	var/list/screens = list()
 
+	/// Contains the blindspot overlays, if they are in use
+	var/list/datum/weakref/blindspot_overlay
+
 	///The HUD type the mob will gain on Initialize. (from 'code/_onclick/hud/hud.dm')
 	var/hud_type = /datum/hud