- partial scriptification of AInventory.

- scriptification of CustomInventory.

src/fragglescript/t_func.cpp

@@ -2620,9 +2620,9 @@ void FParser::SF_MaxPlayerAmmo()
 			if(amount < 0) amount = 0;
 			if (!iammo) 
 			{
-				iammo = static_cast<AInventory *>(Spawn (ammotype));
+				players[playernum].mo->GiveAmmo(ammotype, 1);
+				iammo = players[playernum].mo->FindInventory(ammotype);
 				iammo->Amount = 0;
-				iammo->AttachToOwner (players[playernum].mo);
 			}
 			iammo->MaxAmount = amount;
 

src/g_inventory/a_pickups.cpp

@@ -332,28 +332,6 @@ DEFINE_ACTION_FUNCTION(AInventory, HandlePickup)
 	ACTION_RETURN_BOOL(self->HandlePickup(item));
 }
 
-bool AInventory::CallHandlePickup(AInventory *item)
-{
-	auto self = this;
-	while (self != nullptr)
-	{
-		IFVIRTUALPTR(self, AInventory, HandlePickup)
-		{
-			// Without the type cast this picks the 'void *' assignment...
-			VMValue params[2] = { (DObject*)self, (DObject*)item };
-			VMReturn ret;
-			int retval;
-			ret.IntAt(&retval);
-			GlobalVMStack.Call(func, params, 2, &ret, 1, nullptr);
-			if (retval) return true;
-		}
-		else if (self->HandlePickup(item)) return true;
-		self = self->Inventory;
-	}
-	return false;
-}
-
-
 //===========================================================================
 //
 // AInventory :: GoAway
@@ -450,20 +428,6 @@ DEFINE_ACTION_FUNCTION(AInventory, CreateCopy)
 	ACTION_RETURN_OBJECT(self->CreateCopy(other));
 }
 
-AInventory *AInventory::CallCreateCopy(AActor *other)
-{
-	IFVIRTUAL(AInventory, CreateCopy)
-	{
-		VMValue params[2] = { (DObject*)this, (DObject*)other };
-		VMReturn ret;
-		AInventory *retval;
-		ret.PointerAt((void**)&retval);
-		GlobalVMStack.Call(func, params, 2, &ret, 1, nullptr);
-		return retval;
-	}
-	else return CreateCopy(other);
-}
-
 
 //===========================================================================
 //
@@ -475,47 +439,7 @@ AInventory *AInventory::CallCreateCopy(AActor *other)
 //
 //===========================================================================
 
-AInventory *AInventory::CreateTossable ()
+AInventory *AInventory::CreateTossable()
-{
-	AInventory *copy;
-
-	// If this actor lacks a SpawnState, don't drop it. (e.g. A base weapon
-	// like the fist can't be dropped because you'll never see it.)
-	if (SpawnState == ::GetDefault<AActor>()->SpawnState ||
-		SpawnState == NULL)
-	{
-		return NULL;
-	}
-	if ((ItemFlags & (IF_UNDROPPABLE|IF_UNTOSSABLE)) || Owner == NULL || Amount <= 0)
-	{
-		return NULL;
-	}
-	if (Amount == 1 && !(ItemFlags & IF_KEEPDEPLETED))
-	{
-		BecomePickup ();
-		DropTime = 30;
-		flags &= ~(MF_SPECIAL|MF_SOLID);
-		return this;
-	}
-	copy = static_cast<AInventory *>(Spawn (GetClass(), Owner->Pos(), NO_REPLACE));
-	if (copy != NULL)
-	{
-		copy->MaxAmount = MaxAmount;
-		copy->Amount = 1;
-		copy->DropTime = 30;
-		copy->flags &= ~(MF_SPECIAL|MF_SOLID);
-		Amount--;
-	}
-	return copy;
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, CreateTossable)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	ACTION_RETURN_OBJECT(self->CreateTossable());
-}
-
-AInventory *AInventory::CallCreateTossable()
 {
 	IFVIRTUAL(AInventory, CreateTossable)
 	{
@@ -594,30 +518,6 @@ DEFINE_ACTION_FUNCTION(AInventory, BecomePickup)
 	return 0;
 }
 
-//===========================================================================
-//
-// AInventory :: AbsorbDamage
-//
-// Allows inventory items (primarily armor) to reduce the amount of damage
-// taken. Damage is the amount of damage that would be done without armor,
-// and newdamage is the amount that should be done after the armor absorbs
-// it.
-//
-//===========================================================================
-
-void AInventory::AbsorbDamage (int damage, FName damageType, int &newdamage)
-{
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, AbsorbDamage)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	PARAM_INT(damage);
-	PARAM_NAME(type);
-	PARAM_POINTER(newdmg, int);
-	self->AbsorbDamage(damage, type, *newdmg);
-	return 0;
-}
 //===========================================================================
 //
 // AInventory :: ModifyDamage
@@ -699,18 +599,6 @@ bool AInventory::GetNoTeleportFreeze ()
 //
 //===========================================================================
 
-bool AInventory::Use (bool pickup)
-{
-	return false;
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, Use)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	PARAM_BOOL(pickup);
-	ACTION_RETURN_BOOL(self->Use(pickup));
-}
-
 bool AInventory::CallUse(bool pickup)
 {
 	IFVIRTUAL(AInventory, Use)
@@ -721,9 +609,7 @@ bool AInventory::CallUse(bool pickup)
 		ret.IntAt(&retval);
 		GlobalVMStack.Call(func, params, 2, &ret, 1, nullptr);
 		return !!retval;
-
 	}
-	else return Use(pickup);
 }
 
 
@@ -1153,28 +1039,6 @@ AInventory *AInventory::NextInv ()
 	return item;
 }
 
-//===========================================================================
-//
-// AInventory :: DrawPowerup
-//
-// Gives this item a chance to draw a special status indicator on the screen.
-// Returns false if it didn't draw anything.
-//
-//===========================================================================
-
-bool AInventory::DrawPowerup (int x, int y)
-{
-	return false;
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, DrawPowerup)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	PARAM_INT(x);
-	PARAM_INT(y);
-	ACTION_RETURN_BOOL(self->DrawPowerup(x, y));
-}
-
 //===========================================================================
 //
 // AInventory :: DoRespawn
@@ -1219,117 +1083,6 @@ void AInventory::GiveQuest (AActor *toucher)
 	}
 }
 
-//===========================================================================
-//
-// AInventory :: TryPickup
-//
-//===========================================================================
-
-bool AInventory::TryPickup (AActor *&toucher)
-{
-	AActor *newtoucher = toucher; // in case changed by the powerup
-
-	// If HandlePickup() returns true, it will set the IF_PICKUPGOOD flag
-	// to indicate that this item has been picked up. If the item cannot be
-	// picked up, then it leaves the flag cleared.
-
-	ItemFlags &= ~IF_PICKUPGOOD;
-	if (toucher->Inventory != NULL && toucher->Inventory->CallHandlePickup (this))
-	{
-		// Let something else the player is holding intercept the pickup.
-		if (!(ItemFlags & IF_PICKUPGOOD))
-		{
-			return false;
-		}
-		ItemFlags &= ~IF_PICKUPGOOD;
-		GoAwayAndDie ();
-	}
-	else if (MaxAmount > 0)
-	{
-		// Add the item to the inventory. It is not already there, or HandlePickup
-		// would have already taken care of it.
-		AInventory *copy = CallCreateCopy (toucher);
-		if (copy == NULL)
-		{
-			return false;
-		}
-		// Some powerups cannot activate absolutely, for
-		// example, PowerMorph; fail the pickup if so.
-		if (copy->ItemFlags & IF_INITEFFECTFAILED)
-		{
-			if (copy != this) copy->Destroy();
-			else ItemFlags &= ~IF_INITEFFECTFAILED;
-			return false;
-		}
-		// Handle owner-changing powerups
-		if (copy->ItemFlags & IF_CREATECOPYMOVED)
-		{
-			newtoucher = copy->Owner;
-			copy->Owner = NULL;
-			copy->ItemFlags &= ~IF_CREATECOPYMOVED;
-		}
-		// Continue onwards with the rest
-		copy->CallAttachToOwner (newtoucher);
-		if (ItemFlags & IF_AUTOACTIVATE)
-		{
-			if (copy->CallUse (true))
-			{
-				if (--copy->Amount <= 0)
-				{
-					copy->flags &= ~MF_SPECIAL;
-					copy->SetState (copy->FindState("HoldAndDestroy"));
-				}
-			}
-		}
-	}
-	else if (ItemFlags & IF_AUTOACTIVATE)
-	{
-		// Special case: If an item's MaxAmount is 0, you can still pick it
-		// up if it is autoactivate-able.
-
-		// The item is placed in the inventory just long enough to be used.
-		toucher->AddInventory(this);
-		bool usegood = CallUse(true);
-		toucher->RemoveInventory(this);
-
-		if (usegood)
-		{
-			GoAwayAndDie();
-		}
-		else
-		{
-			return false;
-		}
-	}
-	return true;
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, TryPickup)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	PARAM_POINTER_NOT_NULL(toucher, AActor*);
-	ACTION_RETURN_BOOL(self->TryPickup(*toucher));
-}
-
-//===========================================================================
-//
-// AInventory :: TryPickupRestricted
-//
-//===========================================================================
-
-bool AInventory::TryPickupRestricted (AActor *&toucher)
-{
-	return false;
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, TryPickupRestricted)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	PARAM_POINTER_NOT_NULL(toucher, AActor*);
-	ACTION_RETURN_BOOL(self->TryPickupRestricted(*toucher));
-}
-
-
 //===========================================================================
 //
 // AInventory :: CallTryPickup
@@ -1355,7 +1108,6 @@ bool AInventory::CallTryPickup (AActor *toucher, AActor **toucher_return)
 			GlobalVMStack.Call(func, params, 2, &ret, 1, nullptr);
 			res = !!retval;
 		}
-		else res = TryPickup(toucher);
 	}
 	else if (!(ItemFlags & IF_RESTRICTABSOLUTELY))
 	{
@@ -1369,7 +1121,6 @@ bool AInventory::CallTryPickup (AActor *toucher, AActor **toucher_return)
 			GlobalVMStack.Call(func, params, 2, &ret, 1, nullptr);
 			res = !!retval;
 		}
-		else res = TryPickupRestricted(toucher);
 	}
 	else
 		return false;
@@ -1502,20 +1253,6 @@ CCMD (targetinv)
 //
 //===========================================================================
 
-void AInventory::AttachToOwner (AActor *other)
-{
-	BecomeItem ();
-	other->AddInventory (this);
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, AttachToOwner)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	PARAM_OBJECT_NOT_NULL(other, AActor);
-	self->AttachToOwner(other);
-	return 0;
-}
-
 void AInventory::CallAttachToOwner(AActor *other)
 {
 	IFVIRTUAL(AInventory, AttachToOwner)
@@ -1523,87 +1260,13 @@ void AInventory::CallAttachToOwner(AActor *other)
 		VMValue params[2] = { (DObject*)this, (DObject*)other };
 		GlobalVMStack.Call(func, params, 2, nullptr, 0, nullptr);
 	}
-	else AttachToOwner(other);
 }
 
 
-//===========================================================================
-//
-// AInventory :: DetachFromOwner
-//
-// Performs any special work needed when the item leaves an inventory,
-// either through destruction or becoming a pickup.
-//
-//===========================================================================
-
-void AInventory::DetachFromOwner ()
-{
-}
-
-DEFINE_ACTION_FUNCTION(AInventory, DetachFromOwner)
-{
-	PARAM_SELF_PROLOGUE(AInventory);
-	self->DetachFromOwner();
-	return 0;
-}
-
-void AInventory::CallDetachFromOwner()
-{
-	IFVIRTUAL(AInventory, DetachFromOwner)
-	{
-		VMValue params[1] = { (DObject*)this };
-		GlobalVMStack.Call(func, params, 1, nullptr, 0, nullptr);
-	}
-	else DetachFromOwner();
-}
-
 //===========================================================================
 //===========================================================================
 
 
 
 IMPLEMENT_CLASS(AStateProvider, false, false)
-IMPLEMENT_CLASS(ACustomInventory, false, false)
 
-//===========================================================================
-//
-// ACustomInventory :: SpecialDropAction
-//
-//===========================================================================
-
-bool ACustomInventory::SpecialDropAction (AActor *dropper)
-{
-	return CallStateChain (dropper, FindState(NAME_Drop));
-}
-
-//===========================================================================
-//
-// ACustomInventory :: Use
-//
-//===========================================================================
-
-bool ACustomInventory::Use (bool pickup)
-{
-	return CallStateChain (Owner, FindState(NAME_Use));
-}
-
-//===========================================================================
-//
-// ACustomInventory :: TryPickup
-//
-//===========================================================================
-
-bool ACustomInventory::TryPickup (AActor *&toucher)
-{
-	FState *pickupstate = FindState(NAME_Pickup);
-	bool useok = CallStateChain (toucher, pickupstate);
-	if ((useok || pickupstate == NULL) && FindState(NAME_Use) != NULL)
-	{
-		useok = Super::TryPickup (toucher);
-	}
-	else if (useok)
-	{
-		GoAwayAndDie();
-	}
-	return useok;
-}

src/g_inventory/a_pickups.h

@@ -90,23 +90,17 @@ public:
 	virtual bool SpecialDropAction (AActor *dropper);
 	bool CallSpecialDropAction(AActor *dropper);
 
-	virtual bool TryPickup(AActor *&toucher);
-	virtual bool TryPickupRestricted(AActor *&toucher);
 	bool CallTryPickup(AActor *toucher, AActor **toucher_return = NULL);	// This wraps both virtual methods plus a few more checks. 
 
 	virtual AInventory *CreateCopy(AActor *other);
-	AInventory *CallCreateCopy(AActor *other);
 
-	virtual AInventory *CreateTossable();
+	AInventory *CreateTossable();
-	AInventory *CallCreateTossable();
 
 	virtual FString PickupMessage();
 	FString GetPickupMessage();
 
 	virtual bool HandlePickup(AInventory *item);
-	bool CallHandlePickup(AInventory *item);
 
-	virtual bool Use(bool pickup);
 	bool CallUse(bool pickup);
 
 	virtual PalEntry GetBlend();
@@ -120,20 +114,11 @@ public:
 	virtual void PlayPickupSound(AActor *toucher);
 	void CallPlayPickupSound(AActor *toucher);
 
-	virtual void AttachToOwner(AActor *other);
 	void CallAttachToOwner(AActor *other);
 
-	virtual void DetachFromOwner();
-	void CallDetachFromOwner();
-
 	// still need to be done.
-	virtual void AbsorbDamage(int damage, FName damageType, int &newdamage);
 	void ModifyDamage(int damage, FName damageType, int &newdamage, bool passive);
 
-	// visual stuff is for later. Right now the VM has not yet access to the needed functionality.
-	virtual bool DrawPowerup(int x, int y);
-
-
 	// virtual on the script side only.
 	double GetSpeedFactor();
 	bool GetNoTeleportFreeze();
@@ -151,6 +136,8 @@ public:
 	AInventory *PrevInv();		// Returns the previous item with IF_INVBAR set.
 	AInventory *NextInv();		// Returns the next item with IF_INVBAR set.
 
+	bool CallStateChain(AActor *actor, FState *state);
+
 	TObjPtr<AActor> Owner;		// Who owns this item? NULL if it's still a pickup.
 	int Amount;					// Amount of item this instance has
 	int MaxAmount;				// Max amount of item this instance can have
@@ -180,20 +167,6 @@ class AStateProvider : public AInventory
 	DECLARE_CLASS (AStateProvider, AInventory)
 };
 
-// CustomInventory: Supports the Use, Pickup, and Drop states from 96x
-class ACustomInventory : public AStateProvider
-{
-	DECLARE_CLASS (ACustomInventory, AStateProvider)
-public:
-
-	// This is used when an inventory item's use state sequence is executed.
-	bool CallStateChain (AActor *actor, FState *state);
-
-	virtual bool TryPickup (AActor *&toucher) override;
-	virtual bool Use (bool pickup) override;
-	virtual bool SpecialDropAction (AActor *dropper) override;
-};
-
 extern PClassActor *QuestItemClasses[31];
 
 

src/namedef.h

@@ -196,6 +196,7 @@ xx(PowerWeaponLevel2)
 xx(PowerFlight)
 xx(PowerSpeed)
 xx(PowerTorch)
+xx(CustomInventory)
 
 xx(AcolyteBlue)
 xx(SpectralLightningV1)

src/p_actionfunctions.cpp

@@ -108,7 +108,7 @@ static FRandom pr_bfgselfdamage("BFGSelfDamage");
 //
 //==========================================================================
 
-bool ACustomInventory::CallStateChain (AActor *actor, FState *state)
+bool AInventory::CallStateChain (AActor *actor, FState *state)
 {
 	INTBOOL result = false;
 	int counter = 0;
@@ -223,6 +223,13 @@ bool ACustomInventory::CallStateChain (AActor *actor, FState *state)
 	return !!result;
 }
 
+DEFINE_ACTION_FUNCTION(AInventory, CallStateChain)
+{
+	PARAM_SELF_PROLOGUE(AInventory);
+	PARAM_OBJECT(affectee, AActor);
+	PARAM_STATE(state);
+	ACTION_RETURN_BOOL(self->CallStateChain(affectee, state));
+}
 
 //==========================================================================
 //

src/p_mobj.cpp

@@ -844,7 +844,13 @@ void AActor::RemoveInventory(AInventory *item)
 			if (inv == item)
 			{
 				*invp = item->Inventory;
-				item->DetachFromOwner();
+
+				IFVIRTUALPTR(item, AInventory, DetachFromOwner)
+				{
+					VMValue params[1] = { item };
+					GlobalVMStack.Call(func, params, 1, nullptr, 0, nullptr);
+				}
+
 				item->Owner = NULL;
 				item->Inventory = NULL;
 				break;
@@ -1032,7 +1038,7 @@ DEFINE_ACTION_FUNCTION(AActor, UseInventory)
 
 AInventory *AActor::DropInventory (AInventory *item)
 {
-	AInventory *drop = item->CallCreateTossable ();
+	AInventory *drop = item->CreateTossable ();
 
 	if (drop == NULL)
 	{
@@ -3622,7 +3628,6 @@ int AActor::AbsorbDamage(int damage, FName dmgtype)
 			VMValue params[4] = { item, damage, dmgtype.GetIndex(), &damage };
 			GlobalVMStack.Call(func, params, 4, nullptr, 0, nullptr);
 		}
-		else item->AbsorbDamage(damage, dmgtype, damage);
 	}
 	return damage;
 }

src/scripting/thingdef.cpp

@@ -253,12 +253,16 @@ static void CheckForUnsafeStates(PClassActor *obj)
 		if (obj->Size == RUNTIME_CLASS(AWeapon)->Size) return;	// This class cannot have user variables.
 		test = weaponstates;
 	}
-	else if (obj->IsDescendantOf(RUNTIME_CLASS(ACustomInventory)))
+	else
 	{
-		if (obj->Size == RUNTIME_CLASS(ACustomInventory)->Size) return;	// This class cannot have user variables.
+		auto citype = PClass::FindActor(NAME_CustomInventory);
-		test = pickupstates;
+		if (obj->IsDescendantOf(citype))
+		{
+			if (obj->Size == citype->Size) return;	// This class cannot have user variables.
+			test = pickupstates;
+		}
+		else return;	// something else derived from AStateProvider. We do not know what this may be.
 	}
-	else return;	// something else derived from AStateProvider. We do not know what this may be.
 
 	for (; *test != NAME_None; test++)
 	{
@@ -338,7 +342,7 @@ static void CheckStates(PClassActor *obj)
 	{
 		CheckStateLabels(obj, weaponstates, SUF_WEAPON, "weapon sprites");
 	}
-	else if (obj->IsDescendantOf(RUNTIME_CLASS(ACustomInventory)))
+	else if (obj->IsDescendantOf(PClass::FindActor(NAME_CustomInventory)))
 	{
 		CheckStateLabels(obj, pickupstates, SUF_ITEM, "CustomInventory state chain");
 	}

src/scripting/zscript/zcc_compile.cpp

@@ -2464,7 +2464,12 @@ void ZCCCompiler::CompileFunction(ZCC_StructWork *c, ZCC_FuncDeclarator *f, bool
 		PFunction *virtsym = nullptr;
 		if (cls != nullptr && cls->ParentClass != nullptr) virtsym = dyn_cast<PFunction>(cls->ParentClass->Symbols.FindSymbol(FName(f->Name), true));
 		unsigned vindex = ~0u;
-		if (virtsym != nullptr) vindex = virtsym->Variants[0].Implementation->VirtualIndex;
+		if (virtsym != nullptr)
+		{
+			auto imp = virtsym->Variants[0].Implementation;
+			if (imp != nullptr) vindex = imp->VirtualIndex;
+			else Error(f, "Virtual base function %s not found in %s", FName(f->Name).GetChars(), cls->ParentClass->TypeName.GetChars());
+		}
 
 		if (!(f->Flags & ZCC_Native))
 		{

wadsrc/static/zscript/inventory/inventory.txt

@@ -9,9 +9,9 @@ class Inventory : Actor native
 {
 	const BLINKTHRESHOLD = (4*32);
 
-	native Actor Owner;						// Who owns this item? NULL if it's still a pickup.
+	native Actor Owner;						// Who owns self item? NULL if it's still a pickup.
-	native int Amount;						// Amount of item this instance has
+	native int Amount;						// Amount of item self instance has
-	native int MaxAmount;					// Max amount of item this instance can have
+	native int MaxAmount;					// Max amount of item self instance can have
 	native int InterHubAmount;				// Amount of item that can be kept between hubs or levels
 	native int RespawnTics;					// Tics from pickup time to respawn time
 	native TextureID Icon;					// Icon to show on status bar or HUD
@@ -33,19 +33,13 @@ class Inventory : Actor native
 		Inventory.PickupMessage "$TXT_DEFAULTPICKUPMSG";
 	}
 	
-	virtual native bool Use (bool pickup);
 	virtual native color GetBlend ();
 	virtual native bool HandlePickup(Inventory item);
 	virtual native Inventory CreateCopy(Actor other);
-	virtual native Inventory CreateTossable();
 	virtual native bool SpecialDropAction (Actor dropper);
 	virtual native String PickupMessage();
 	virtual native bool ShouldStay();
 	virtual native void PlayPickupSound(Actor user);
-	virtual native void AttachToOwner(Actor user);
-	virtual native void DetachFromOwner();
-	virtual native bool DrawPowerup(int x, int y);
-	virtual native void AbsorbDamage (int damage, Name damageType, out int newdamage);
 	
 	native bool DoRespawn();
 	native bool GoAway();
@@ -55,9 +49,8 @@ class Inventory : Actor native
 	
 	// In this case the caller function is more than a simple wrapper around the virtual method and
 	// is what must be actually called to pick up an item.
-	virtual protected native bool TryPickup(in out Actor toucher);
-	virtual protected native bool TryPickupRestricted(in out Actor toucher);
 	native bool, Actor CallTryPickup(Actor toucher);
+	native bool CallStateChain (Actor actor, State state);
 
 	States(Actor, Overlay, Weapon, Item)
 	{
@@ -138,6 +131,188 @@ class Inventory : Actor native
 		}
 	}
 		
+
+	//===========================================================================
+	//
+	// AInventory :: CallHandlePickup
+	//
+	// Runs all HandlePickup methods in the chain
+	//
+	//===========================================================================
+
+	private bool CallHandlePickup(Inventory item)
+	{
+		let me = self;
+		while (me != null)
+		{
+			if (me.HandlePickup(item)) return true;
+			me = me.Inv;
+		}
+		return false;
+	}
+		
+	//===========================================================================
+	//
+	// AInventory :: TryPickup
+	//
+	//===========================================================================
+
+	virtual protected bool TryPickup (in out Actor toucher)
+	{
+		Actor newtoucher = toucher; // in case changed by the powerup
+
+		// If HandlePickup() returns true, it will set the IF_PICKUPGOOD flag
+		// to indicate that self item has been picked up. If the item cannot be
+		// picked up, then it leaves the flag cleared.
+
+		bPickupGood = false;
+		if (toucher.Inv != NULL && toucher.Inv.CallHandlePickup (self))
+		{
+			// Let something else the player is holding intercept the pickup.
+			if (!bPickupGood)
+			{
+				return false;
+			}
+			bPickupGood = false;
+			GoAwayAndDie ();
+		}
+		else if (MaxAmount > 0)
+		{
+			// Add the item to the inventory. It is not already there, or HandlePickup
+			// would have already taken care of it.
+			let copy = CreateCopy (toucher);
+			if (copy == NULL)
+			{
+				return false;
+			}
+			// Some powerups cannot activate absolutely, for
+			// example, PowerMorph; fail the pickup if so.
+			if (copy.bInitEffectFailed)
+			{
+				if (copy != self) copy.Destroy();
+				else bInitEffectFailed;
+				return false;
+			}
+			// Handle owner-changing powerups
+			if (copy.bCreateCopyMoved)
+			{
+				newtoucher = copy.Owner;
+				copy.Owner = NULL;
+				bCreateCopyMoved = false;
+			}
+			// Continue onwards with the rest
+			copy.AttachToOwner (newtoucher);
+			if (bAutoActivate)
+			{
+				if (copy.Use (true))
+				{
+					if (--copy.Amount <= 0)
+					{
+						copy.bSpecial = false;
+						copy.SetStateLabel ("HoldAndDestroy");
+					}
+				}
+			}
+		}
+		else if (bAutoActivate)
+		{
+			// Special case: If an item's MaxAmount is 0, you can still pick it
+			// up if it is autoactivate-able.
+
+			// The item is placed in the inventory just long enough to be used.
+			toucher.AddInventory(self);
+			bool usegood = Use(true);
+			toucher.RemoveInventory(self);
+
+			if (usegood)
+			{
+				GoAwayAndDie();
+			}
+			else
+			{
+				return false;
+			}
+		}
+		return true;
+	}
+
+	//===========================================================================
+	//
+	// AInventory :: TryPickupRestricted
+	//
+	//===========================================================================
+
+	virtual bool TryPickupRestricted (in out Actor toucher)
+	{
+		return false;
+	}
+
+	//===========================================================================
+	//
+	// AInventory :: AttachToOwner
+	//
+	//===========================================================================
+
+	virtual void AttachToOwner (Actor other)
+	{
+		BecomeItem ();
+		other.AddInventory (self);
+	}
+
+	//===========================================================================
+	//
+	// AInventory :: DetachFromOwner
+	//
+	// Performs any special work needed when the item leaves an inventory,
+	// either through destruction or becoming a pickup.
+	//
+	//===========================================================================
+
+	virtual void DetachFromOwner ()
+	{
+	}
+
+	//===========================================================================
+	//
+	// AInventory::CreateTossable
+	//
+	// Creates a copy of the item suitable for dropping. If this actor embodies
+	// only one item, then it is tossed out itself. Otherwise, the count drops
+	// by one and a new item with an amount of 1 is spawned.
+	//
+	//===========================================================================
+
+	virtual Inventory CreateTossable ()
+	{
+		// If self actor lacks a SpawnState, don't drop it. (e.g. A base weapon
+		// like the fist can't be dropped because you'll never see it.)
+		if (SpawnState == GetDefaultByType("Actor").SpawnState || SpawnState == NULL)
+		{
+			return NULL;
+		}
+		if (bUndroppable || bUntossable || Owner == NULL || Amount <= 0)
+		{
+			return NULL;
+		}
+		if (Amount == 1 && !bKeepDepleted)
+		{
+			BecomePickup ();
+			DropTime = 30;
+			bSpecial = bSolid = false;
+			return self;
+		}
+		let copy = Inventory(Spawn (GetClass(), Owner.Pos, NO_REPLACE));
+		if (copy != NULL)
+		{
+			copy.MaxAmount = MaxAmount;
+			copy.Amount = 1;
+			copy.DropTime = 30;
+			copy.bSpecial = copy.bSolid = false;
+			Amount--;
+		}
+		return copy;
+	}
+
 	//===========================================================================
 	//
 	// AInventory :: DepleteOrDestroy
@@ -186,11 +361,37 @@ class Inventory : Actor native
 
 	virtual void DoEffect() {}
 	
+	
+	virtual bool Use (bool pickup) { return false; }
 	virtual double GetSpeedFactor() { return 1; }
 	virtual bool GetNoTeleportFreeze() { return false; }
 	virtual void ModifyDamage(int damage, Name damageType, out int newdamage, bool passive) {}
 	virtual void AlterWeaponSprite(VisStyle vis, in out int changed) {}
 	virtual void OwnerDied() {}
+
+	//===========================================================================
+	//
+	// AInventory :: DrawPowerup
+	//
+	// Gives self item a chance to draw a special status indicator on the screen.
+	// Returns false if it didn't draw anything.
+	//
+	//===========================================================================
+
+	virtual bool DrawPowerup(int x, int y) { return false; }
+
+	//===========================================================================
+	//
+	// AInventory :: AbsorbDamage
+	//
+	// Allows inventory items (primarily armor) to reduce the amount of damage
+	// taken. Damage is the amount of damage that would be done without armor,
+	// and newdamage is the amount that should be done after the armor absorbs
+	// it.
+	//
+	//===========================================================================
+
+	virtual void AbsorbDamage (int damage, Name damageType, out int newdamage) {}
 	
 }
 

wadsrc/static/zscript/inventory/stateprovider.txt

@@ -36,4 +36,48 @@ class CustomInventory : StateProvider native
 	deprecated action void A_Lower() {}
 	deprecated action void A_Raise() {}
 	deprecated action void A_CheckReload() {}
+	
+	//===========================================================================
+	//
+	// ACustomInventory :: SpecialDropAction
+	//
+	//===========================================================================
+
+	override bool SpecialDropAction (Actor dropper)
+	{
+		return CallStateChain (dropper, FindState('Drop'));
+	}
+
+	//===========================================================================
+	//
+	// ACustomInventory :: Use
+	//
+	//===========================================================================
+
+	override bool Use (bool pickup)
+	{
+		return CallStateChain (Owner, FindState('Use'));
+	}
+
+	//===========================================================================
+	//
+	// ACustomInventory :: TryPickup
+	//
+	//===========================================================================
+
+	override bool TryPickup (in out Actor toucher)
+	{
+		let pickupstate = FindState('Pickup');
+		bool useok = CallStateChain (toucher, pickupstate);
+		if ((useok || pickupstate == NULL) && FindState('Use') != NULL)
+		{
+			useok = Super.TryPickup (toucher);
+		}
+		else if (useok)
+		{
+			GoAwayAndDie();
+		}
+		return useok;
+	}
+	
 }