World Icons (#2279)

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## About The Pull Request
Ports world icons from Mojave 13.
This is an element that allows for tiny, size-accurate versions of
object sprites in a roundabout way.

~~Drafted since spritainers want more coverage before merging~~
UNDRAFTED by request of a spritainer. God weeps


### //MAKING A SUPER BASIC WORLD ICON IMPLEMENTATION GUIDE: FOR REAL. NO
VIRUS. 100% ORGANIC//

- Place the Element in an Init below The Item In Question

`/obj/item/Initialize()`
`	. = ..()`
`	AddElement(/datum/element/world_icon, null, icon, 'icon')`

- Fill in info. Put the ORIGINAL ICON in the addelement's `'icon'` slot
(yeah, this element layers the "original" sprite on top of the worldicon
one, using it as the default. It just be like that sometimes)

`/obj/item/kitchen/knife/combat/Initialize()`
`	. = ..()`
` AddElement(/datum/element/world_icon, null, icon,
'icons/obj/kitchen.dmi')`
	
- Put the directory to your NEW, WORLD ICON in the item's normal icon
var
	`icon = 'icons/obj/world/melee.dmi'`	

The world icon and icon adjustment vars on obj/item should allow for
implementation in places where an object's Icon has to frequently
change.

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## Why It's Good For The Game
Just a little guy
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## Changelog

:cl:
add: World icon element.
add: World icons for combat knives.
/:cl:

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---------

Signed-off-by: Sun-Soaked <[email protected]>
Co-authored-by: Sun-Soaked <[email protected]>
Co-authored-by: FalloutFalcon <[email protected]>

code/datums/components/forensics.dm

@@ -192,4 +192,4 @@
 		return
 	if(isitem(parent))
 		var/obj/item/I = parent
-		I.AddElement(/datum/element/decal/blood, initial(I.icon) || I.icon, initial(I.icon_state) || I.icon_state, _color = get_blood_dna_color(blood_DNA))
+		I.AddElement(/datum/element/decal/blood, I.icon, I.icon_state, _color = get_blood_dna_color(blood_DNA))

code/datums/elements/decals/blood.dm

@@ -6,9 +6,11 @@
 
 	. = ..()
 	RegisterSignal(target, COMSIG_ATOM_GET_EXAMINE_NAME, PROC_REF(get_examine_name), TRUE)
+	RegisterSignal(target, list(COMSIG_ITEM_EQUIPPED, COMSIG_ITEM_DROPPED), PROC_REF(redraw), TRUE)
 
 /datum/element/decal/blood/Detach(atom/source, force)
 	UnregisterSignal(source, COMSIG_ATOM_GET_EXAMINE_NAME)
+	UnregisterSignal(source, list(COMSIG_ITEM_EQUIPPED, COMSIG_ITEM_DROPPED))
 	return ..()
 
 /datum/element/decal/blood/generate_appearance(_icon, _icon_state, _dir, _layer, _color, _alpha, source)
@@ -30,3 +32,11 @@
 	override[EXAMINE_POSITION_ARTICLE] = A.gender == PLURAL? "some" : "a"
 	override[EXAMINE_POSITION_BEFORE] = " blood-stained "
 	return COMPONENT_EXNAME_CHANGED
+
+///this is probably quite bad, let me know if you have a better solution for this -S
+/datum/element/decal/blood/proc/redraw(datum/source, mob/user)
+	SIGNAL_HANDLER
+
+	var/atom/bloodsource = source
+	Detach(source)
+	bloodsource.AddElement(/datum/element/decal/blood, bloodsource.icon, bloodsource.icon_state, _color = get_blood_dna_color(bloodsource.return_blood_DNA()))

code/datums/elements/world_icon.dm

@@ -0,0 +1,121 @@
+/////////////////////////////////////////////////////////////
+////////// WORLD ICON ELEMENT DIRECTORY //////////
+/////////////////////////////////////////////////////////////
+//PORTED FROM MOJAVE SUN//
+
+// Slap onto something to give it a world icon that differs from the inventory one (allows for realistically sized objects and all that) //
+// To fix 25/06/2021 : Blood Decals, Mutable Overlays and other baked in bitch ass overlays that need to be remade when the icon changes //
+// Fixed 07/05/2022: Now you can deal with the above by handling everything with attached_proc instead
+// Fixed 12/04/2023: Icon states, Needs major tuning up by someone who can properly make it work
+
+/datum/element/world_icon
+	id_arg_index = 2
+	element_flags = ELEMENT_BESPOKE | ELEMENT_DETACH
+	//If we want COMPLEX world icon behavior, this proc will handle icon updating when the item is NOT in the inventory.
+	//I just assumed that the default update_icon is for inventory sprites because ss13 basically focuses on how the sprites
+	//look on your hand, not how they realistically look in the world.
+	var/attached_proc
+	/// Only used if attached_proc doesn't exist, simply changes the icon of target to this when it's in the inventory
+	var/inventory_icon
+	/// Only used if attached_proc doesn't exist, simply changes the icon of target to this when it's NOT in the inventory
+	var/world_icon
+	/// Only used when inventory state icon is different from original
+	var/inventory_icon_state
+	/// Only used when world state icon is different from original, pretty much just the original "icon_state" but if you for some reason need to flip the standard icon states for this element around you can use this
+	var/world_icon_state
+
+/datum/element/world_icon/Attach(obj/item/target, attached_proc, world_icon, inventory_icon, world_icon_state, inventory_icon_state)
+	. = ..()
+	if(!istype(target))
+		return ELEMENT_INCOMPATIBLE
+
+	src.attached_proc = attached_proc
+	src.world_icon = world_icon
+	src.world_icon_state = world_icon_state
+	src.inventory_icon = inventory_icon
+	src.inventory_icon_state = inventory_icon_state
+	RegisterSignal(target, COMSIG_ATOM_UPDATE_ICON, PROC_REF(update_icon))
+	RegisterSignal(target, COMSIG_ATOM_UPDATE_ICON_STATE, PROC_REF(update_icon_state))
+	RegisterSignal(target, list(COMSIG_ITEM_EQUIPPED, COMSIG_STORAGE_ENTERED, COMSIG_ITEM_DROPPED, COMSIG_STORAGE_EXITED), PROC_REF(inventory_updated))
+	target.update_appearance(UPDATE_ICON)
+	target.update_appearance(UPDATE_ICON_STATE)
+
+/datum/element/world_icon/Detach(obj/item/source)
+	. = ..()
+	UnregisterSignal(source, COMSIG_ATOM_UPDATE_ICON)
+	UnregisterSignal(source, COMSIG_ATOM_UPDATE_ICON_STATE, PROC_REF(update_icon_state))
+	UnregisterSignal(source, list(COMSIG_ITEM_EQUIPPED, COMSIG_STORAGE_ENTERED, COMSIG_ITEM_DROPPED, COMSIG_STORAGE_EXITED))
+	source.update_appearance(UPDATE_ICON)
+	source.update_appearance(UPDATE_ICON_STATE)
+
+/datum/element/world_icon/proc/update_icon(obj/item/source, updates)
+	SIGNAL_HANDLER
+
+	if((source.item_flags & IN_INVENTORY) || (source.loc && SEND_SIGNAL(source.loc, COMSIG_CONTAINS_STORAGE)))
+		if(attached_proc)
+			return
+		return default_inventory_icon(source)
+
+	if(attached_proc)
+		return call(source, attached_proc)(updates)
+	else
+		return default_world_icon(source)
+
+/datum/element/world_icon/proc/update_icon_state(obj/item/source, updates)
+	SIGNAL_HANDLER
+
+	if((source.item_flags & IN_INVENTORY) || (source.loc && SEND_SIGNAL(source.loc, COMSIG_CONTAINS_STORAGE)))
+		if(attached_proc)
+			return
+		return default_inventory_icon_state(source)
+
+	if(attached_proc)
+		return call(source, attached_proc)(updates)
+	else
+		return default_world_icon_state(source)
+
+/datum/element/world_icon/proc/inventory_updated(obj/item/source)
+	SIGNAL_HANDLER
+
+	source.update_appearance(UPDATE_ICON)
+	source.update_appearance(UPDATE_ICON_STATE)
+
+/datum/element/world_icon/proc/default_inventory_icon(obj/item/source)
+	SIGNAL_HANDLER
+
+	source.icon = inventory_icon
+
+/datum/element/world_icon/proc/default_world_icon(obj/item/source)
+	SIGNAL_HANDLER
+
+	source.icon = world_icon
+
+/datum/element/world_icon/proc/default_inventory_icon_state(obj/item/source)
+	SIGNAL_HANDLER
+
+	if(!inventory_icon_state)
+		source.icon_state = source.icon_state
+		return
+
+	INVOKE_ASYNC(src, PROC_REF(check_inventory_state), source)
+
+/datum/element/world_icon/proc/default_world_icon_state(obj/item/source)
+	SIGNAL_HANDLER
+
+	if(!world_icon_state)
+		source.icon_state = source.icon_state
+		return
+
+	INVOKE_ASYNC(src, PROC_REF(check_world_icon_state), source)
+
+/datum/element/world_icon/proc/check_inventory_state(obj/item/source)
+	SIGNAL_HANDLER
+
+	inventory_icon_state = source.inventory_state
+	source.icon_state = inventory_icon_state
+
+/datum/element/world_icon/proc/check_world_icon_state(obj/item/source)
+	SIGNAL_HANDLER
+
+	world_icon_state = source.world_state
+	source.icon_state = world_icon_state

code/game/objects/items.dm

@@ -202,6 +202,10 @@ 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)
@@ -518,12 +522,12 @@ GLOBAL_VAR_INIT(embedpocalypse, FALSE) // if true, all items will be able to emb
 /obj/item/proc/equipped(mob/user, slot, initial = FALSE)
 	SHOULD_CALL_PARENT(1)
 	visual_equipped(user, slot, initial)
-	SEND_SIGNAL(src, COMSIG_ITEM_EQUIPPED, user, slot)
 	for(var/X in actions)
 		var/datum/action/A = X
 		if(item_action_slot_check(slot, user)) //some items only give their actions buttons when in a specific slot.
 			A.Grant(user)
 	item_flags |= IN_INVENTORY
+	SEND_SIGNAL(src, COMSIG_ITEM_EQUIPPED, user, slot)
 	if(!initial)
 		if(equip_sound && (slot_flags & slot))
 			playsound(src, equip_sound, EQUIP_SOUND_VOLUME, TRUE, ignore_walls = FALSE)

code/game/objects/items/kitchen.dm

@@ -179,6 +179,7 @@
 
 /obj/item/kitchen/knife/combat
 	name = "combat knife"
+	icon = 'icons/obj/world/melee.dmi'
 	icon_state = "combatknife"
 	item_state = "combatknife"
 	desc = "A military combat utility survival knife."
@@ -188,6 +189,10 @@
 	attack_verb = list("slashed", "stabbed", "sliced", "torn", "ripped", "cut")
 	bayonet = TRUE
 
+/obj/item/kitchen/knife/combat/Initialize()
+	. = ..()
+	AddElement(/datum/element/world_icon, null, icon, 'icons/obj/kitchen.dmi')
+
 /obj/item/kitchen/knife/combat/survival
 	name = "survival knife"
 	icon_state = "survivalknife"

shiptest.dme

@@ -655,6 +655,7 @@
 #include "code\datums\elements\update_icon_blocker.dm"
 #include "code\datums\elements\update_icon_updates_onmob.dm"
 #include "code\datums\elements\waddling.dm"
+#include "code\datums\elements\world_icon.dm"
 #include "code\datums\elements\decals\_decals.dm"
 #include "code\datums\elements\decals\blood.dm"
 #include "code\datums\helper_datums\events.dm"