World icon 2 (#3516)

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## About The Pull Request
World icon now only require setting the world_file var to work
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## Why It's Good For The Game
easier
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## Changelog

:cl:
add: Readdes world icons for a few knives. Expect more soon!
/:cl:

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code/datums/elements/world_icon.dm

@@ -103,7 +103,7 @@
 	SIGNAL_HANDLER
 
 	if(!world_icon_state)
-		source.icon_state = source.icon_state
+		source.icon_state = source.item_state
 		return
 
 	INVOKE_ASYNC(src, PROC_REF(check_world_icon_state), source)

code/game/objects/items.dm

@@ -26,6 +26,14 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 	///Icon file for right inhand overlays
 	var/righthand_file = 'icons/mob/inhands/items_righthand.dmi'
 
+	///If set it will add a world icon using item_state
+	var/world_file
+
+	///Handled by world_icon element
+	var/world_state
+	///Handled by world_icon element
+	var/inventory_state
+
 	///This is a bitfield that defines what variations exist for bodyparts like Digi legs.
 	var/supports_variations = null
 
@@ -207,10 +215,6 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 
 	var/canMouseDown = FALSE
 
-	//for setting world icons on the go
-	var/inventory_state
-	var/world_state
-
 /obj/item/Initialize()
 
 	if(attack_verb)
@@ -309,6 +313,9 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 
 	updateEmbedding()
 
+	if(world_file)
+		AddElement(/datum/element/world_icon, null, world_file, icon)
+
 	if(GLOB.rpg_loot_items)
 		AddComponent(/datum/component/fantasy)
 

code/game/objects/items/melee/knife.dm

@@ -105,6 +105,7 @@
 	force = 20
 	throwforce = 20
 	attack_verb = list("slashed", "stabbed", "sliced", "torn", "ripped", "cut")
+	world_file = 'icons/obj/world/melee.dmi'
 
 /obj/item/melee/knife/survival
 	name = "survival knife"
@@ -115,6 +116,7 @@
 	force = 15
 	throwforce = 15
 	attack_verb = list("slashed", "stabbed", "sliced", "torn", "ripped", "cut")
+	world_file = 'icons/obj/world/melee.dmi'
 
 /obj/item/melee/knife/bone
 	name = "bone dagger"
@@ -127,6 +129,7 @@
 	force = 15
 	throwforce = 15
 	custom_materials = null
+	world_file = 'icons/obj/world/melee.dmi'
 
 /obj/item/melee/knife/combat/cyborg
 	name = "cyborg knife"