gzdoom-gles/wadsrc/static/zscript/actor_inventory.txt

extend class Actor
{
	//============================================================================
	//
	// AActor :: AddInventory
	//
	//============================================================================

	virtual void AddInventory (Inventory item)
	{
		// Check if it's already attached to an actor
		if (item.Owner != NULL)
		{
			// Is it attached to us?
			if (item.Owner == self)
				return;

			// No, then remove it from the other actor first
			item.Owner.RemoveInventory (item);
		}

		item.Owner = self;
		item.Inv = Inv;
		Inv = item;

		// Each item receives an unique ID when added to an actor's inventory.
		// This is used by the DEM_INVUSE command to identify the item. Simply
		// using the item's position in the list won't work, because ticcmds get
		// run sometime in the future, so by the time it runs, the inventory
		// might not be in the same state as it was when DEM_INVUSE was sent.
		Inv.InventoryID = InventoryID++;
	}

	//============================================================================
	//
	// AActor :: GiveInventory
	//
	//============================================================================
	
	bool GiveInventory(Class<Inventory> type, int amount, bool givecheat = false)
	{
		bool result = true;
		let player = self.player;

		// This can be called from places which do not check the given item's type.
		if (type == null || !(type is 'Inventory')) return false;

		Weapon savedPendingWeap = player != NULL ? player.PendingWeapon : NULL;
		bool hadweap = player != NULL ? player.ReadyWeapon != NULL : true;

		Inventory item;
		if (!givecheat)
		{
			item = Inventory(Spawn (type));
		}
		else
		{
			item = Inventory(Spawn (type, Pos, NO_REPLACE));
			if (item == NULL) return false;
		}

		// This shouldn't count for the item statistics.
		item.ClearCounters();
		if (!givecheat || amount > 0)
		{
			item.SetGiveAmount(self, amount, givecheat);
		}
		if (!item.CallTryPickup (self))
		{
			item.Destroy ();
			result = false;
		}
		// If the item was a weapon, don't bring it up automatically
		// unless the player was not already using a weapon.
		// Don't bring it up automatically if this is called by the give cheat.
		if (!givecheat && player != NULL && savedPendingWeap != NULL && hadweap)
		{
			player.PendingWeapon = savedPendingWeap;
		}
		return result;
	}

	//============================================================================
	//
	// AActor :: RemoveInventory
	//
	//============================================================================

	virtual void RemoveInventory(Inventory item)
	{
		Inventory invp;

		if (item != NULL && item.Owner != NULL)	// can happen if the owner was destroyed by some action from an item's use state.
		{
			if (Inv == item) Inv = item.Inv;
			else
			{
				for (invp = Inv; invp != null; invp = invp.Inv)
				{
					if (invp.Inv == item)
					{
						invp.Inv = item.Inv;
						item.DetachFromOwner();
						break;
					}
				}
			}
			item.Owner = NULL;
			item.Inv = NULL;
		}
	}

	//============================================================================
	//
	// AActor :: TakeInventory
	//
	//============================================================================

	bool TakeInventory(class<Inventory> itemclass, int amount, bool fromdecorate = false, bool notakeinfinite = false)
	{
		amount = abs(amount);
		let item = FindInventory(itemclass);

		if (item == NULL)
			return false;

		if (!fromdecorate)
		{
			item.Amount -= amount;
			if (item.Amount <= 0)
			{
				item.DepleteOrDestroy();
			}
			// It won't be used in non-decorate context, so return false here
			return false;
		}

		bool result = false;
		if (item.Amount > 0)
		{
			result = true;
		}

		// Do not take ammo if the "no take infinite/take as ammo depletion" flag is set
		// and infinite ammo is on
		if (notakeinfinite &&
		(sv_infiniteammo || (player && FindInventory('PowerInfiniteAmmo', true))) && (item is 'Ammo'))
		{
			// Nothing to do here, except maybe res = false;? Would it make sense?
			result = false;
		}
		else if (!amount || amount >= item.Amount)
		{
			item.DepleteOrDestroy();
		}
		else item.Amount -= amount;

		return result;
	}


}