[MIRROR] Adds an HUD button to change your z-level

code/__DEFINES/hud.dm

@@ -77,6 +77,7 @@
 #define ui_building "EAST-4:22,SOUTH:21"
 #define ui_language_menu "EAST-4:6,SOUTH:21"
 #define ui_navigate_menu "EAST-4:22,SOUTH:5"
+#define ui_floor_menu "EAST-4:14,SOUTH:37"
 
 //Upper-middle right (alerts)
 #define ui_alert1 "EAST-1:28,CENTER+5:27"
@@ -143,6 +144,7 @@
 #define ui_borg_alerts "CENTER+4:21,SOUTH:5"
 #define ui_borg_language_menu "CENTER+4:19,SOUTH+1:6"
 #define ui_borg_navigate_menu "CENTER+4:19,SOUTH+1:6"
+#define ui_borg_floor_menu "CENTER+4:-13,SOUTH+1:6"
 
 //Aliens
 #define ui_alien_health "EAST,CENTER-1:15"
@@ -151,6 +153,7 @@
 #define ui_alien_storage_r "CENTER+1:18,SOUTH:5"
 #define ui_alien_language_menu "EAST-4:20,SOUTH:5"
 #define ui_alien_navigate_menu "EAST-4:20,SOUTH:5"
+#define ui_alien_floor_menu "EAST-4:-12,SOUTH:5"
 
 //AI
 #define ui_ai_core "BOTTOM:6,RIGHT-4"
@@ -159,6 +162,7 @@
 #define ui_ai_state_laws "BOTTOM:6,RIGHT-1"
 #define ui_ai_mod_int "BOTTOM:6,RIGHT"
 #define ui_ai_language_menu "BOTTOM+1:8,RIGHT-1:30"
+#define ui_ai_floor_menu "BOTTOM+1:8,RIGHT-1:14"
 
 #define ui_ai_crew_monitor "BOTTOM:6,CENTER-1"
 #define ui_ai_crew_manifest "BOTTOM:6,CENTER"
@@ -200,6 +204,7 @@
 #define ui_ghost_pai "SOUTH: 6, CENTER+1:24"
 #define ui_ghost_minigames "SOUTH: 6, CENTER+2:24"
 #define ui_ghost_language_menu "SOUTH: 22, CENTER+3:8"
+#define ui_ghost_floor_menu "SOUTH: 6, CENTER+3:8"
 
 //Blobbernauts
 #define ui_blobbernaut_overmind_health "EAST-1:28,CENTER+0:19"

code/_onclick/hud/ai.dm

@@ -186,6 +186,11 @@
 	using.screen_loc = ui_ai_language_menu
 	static_inventory += using
 
+// Z-level floor change
+	using = new /atom/movable/screen/floor_menu(null, src)
+	using.screen_loc = ui_ai_floor_menu
+	static_inventory += using
+
 //AI core
 	using = new /atom/movable/screen/ai/aicore(null, src)
 	using.screen_loc = ui_ai_core

code/_onclick/hud/alien.dm

@@ -63,6 +63,10 @@
 	using.screen_loc = ui_alien_language_menu
 	static_inventory += using
 
+	using = new /atom/movable/screen/floor_menu(null, src)
+	using.screen_loc = ui_alien_floor_menu
+	static_inventory += using
+
 	using = new /atom/movable/screen/navigate(null, src)
 	using.screen_loc = ui_alien_navigate_menu
 	static_inventory += using
@@ -87,7 +91,7 @@
 	pull_icon.update_appearance()
 	pull_icon.screen_loc = ui_above_movement
 	static_inventory += pull_icon
-		
+
 	rest_icon = new /atom/movable/screen/rest(null, src)
 	rest_icon.icon = ui_style
 	rest_icon.screen_loc = ui_above_intent

code/_onclick/hud/alien_larva.dm

@@ -32,6 +32,10 @@
 	using.screen_loc = ui_alien_language_menu
 	static_inventory += using
 
+	using = new /atom/movable/screen/floor_menu(null, src)
+	using.screen_loc = ui_alien_floor_menu
+	static_inventory += using
+
 	using = new /atom/movable/screen/navigate(null, src)
 	using.screen_loc = ui_alien_navigate_menu
 	static_inventory += using

code/_onclick/hud/ghost.dm

@@ -86,6 +86,16 @@
 	using.icon = ui_style
 	static_inventory += using
 
+	using = new /atom/movable/screen/language_menu(null, src)
+	using.screen_loc = ui_ghost_language_menu
+	using.icon = ui_style
+	static_inventory += using
+
+	using = new /atom/movable/screen/floor_menu(null, src)
+	using.screen_loc = ui_ghost_floor_menu
+	using.icon = ui_style
+	static_inventory += using
+
 /datum/hud/ghost/show_hud(version = 0, mob/viewmob)
 	// don't show this HUD if observing; show the HUD of the observee
 	var/mob/dead/observer/O = mymob

code/_onclick/hud/human.dm

@@ -70,6 +70,10 @@
 	using.icon = ui_style
 	static_inventory += using
 
+	using = new /atom/movable/screen/floor_menu(null, src)
+	using.icon = ui_style
+	static_inventory += using
+
 	action_intent = new /atom/movable/screen/combattoggle/flashy(null, src)
 	action_intent.icon = ui_style
 	action_intent.screen_loc = ui_combat_toggle

code/_onclick/hud/robot.dm

@@ -77,6 +77,7 @@
 	var/mob/living/silicon/robot/robit = mymob
 	var/atom/movable/screen/using
 
+// Language
 	using = new/atom/movable/screen/language_menu(null, src)
 	using.screen_loc = ui_borg_language_menu
 	static_inventory += using
@@ -86,6 +87,11 @@
 	using.screen_loc = ui_borg_navigate_menu
 	static_inventory += using
 
+// Z-level floor change
+	using = new /atom/movable/screen/floor_menu(null, src)
+	using.screen_loc = ui_borg_floor_menu
+	static_inventory += using
+
 //Radio
 	using = new /atom/movable/screen/robot/radio(null, src)
 	using.screen_loc = ui_borg_radio

code/_onclick/hud/screen_objects.dm

@@ -127,6 +127,33 @@
 /atom/movable/screen/language_menu/Click()
 	usr.get_language_holder().open_language_menu(usr)
 
+/atom/movable/screen/floor_menu
+	name = "change floor"
+	icon = 'icons/hud/screen_midnight.dmi'
+	icon_state = "floor_change"
+	screen_loc = ui_floor_menu
+
+/atom/movable/screen/floor_menu/Initialize(mapload)
+	. = ..()
+	register_context()
+
+/atom/movable/screen/floor_menu/add_context(atom/source, list/context, obj/item/held_item, mob/user)
+	. = ..()
+
+	context[SCREENTIP_CONTEXT_LMB] = "Go up a floor"
+	context[SCREENTIP_CONTEXT_RMB] = "Go down a floor"
+	return CONTEXTUAL_SCREENTIP_SET
+
+/atom/movable/screen/floor_menu/Click(location,control,params)
+	var/list/modifiers = params2list(params)
+
+	if(LAZYACCESS(modifiers, RIGHT_CLICK) || LAZYACCESS(modifiers, ALT_CLICK))
+		usr.down()
+		return
+
+	usr.up()
+	return
+
 /atom/movable/screen/inventory
 	/// The identifier for the slot. It has nothing to do with ID cards.
 	var/slot_id