- some cleanup on the weapon slot interface.

This really shouldn't make any decisions from directly reading weapon class defaults.

src/d_dehacked.cpp

@@ -3095,7 +3095,7 @@ void FinishDehPatch ()
 		}
 		else
 		{
-			weap->WeaponFlags |= WIF_DEHAMMO;
+			weap->bDehAmmo = true;
 			weap->AmmoUse1 = 0;
 			// to allow proper checks in CheckAmmo we have to find the first attack pointer in the Fire sequence
 			// and set its default ammo use as the weapon's AmmoUse1.

src/g_inventory/a_weapons.cpp

@@ -83,9 +83,8 @@ DEFINE_FIELD(AWeapon, FOVScale)
 DEFINE_FIELD(AWeapon, Crosshair)					
 DEFINE_FIELD(AWeapon, GivenAsMorphWeapon)
 DEFINE_FIELD(AWeapon, bAltFire)
-DEFINE_FIELD(AWeapon, SlotNumber)
 DEFINE_FIELD(AWeapon, WeaponFlags)
-DEFINE_FIELD_BIT(AWeapon, WeaponFlags, bDehAmmo, WIF_DEHAMMO)
+DEFINE_FIELD(AWeapon, bDehAmmo)
 
 //===========================================================================
 //
@@ -482,18 +481,23 @@ void FWeaponSlots::AddExtraWeapons()
 		{
 			continue;
 		}
-		auto weapdef = ((AWeapon*)GetDefaultByType(cls));
-		auto gf = cls->ActorInfo()->GameFilter;
-		if ((gf == GAME_Any || (gf & gameinfo.gametype)) &&
-			cls->ActorInfo()->Replacement == nullptr &&		// Replaced weapons don't get slotted.
-			!(weapdef->WeaponFlags & WIF_POWERED_UP) &&
-			!LocateWeapon(cls, nullptr, nullptr)		// Don't duplicate it if it's already present.
-			)
+		if (LocateWeapon(cls, nullptr, nullptr))	// Do we already have it? Don't add it again.
 		{
-			int slot = weapdef->SlotNumber;
-			if ((unsigned)slot < NUM_WEAPON_SLOTS)
+			continue;
+		}
+		auto weapdef = ((AWeapon*)GetDefaultByType(cls));
+
+		// Let the weapon decide for itself if it wants to get added to a slot.
+		IFVIRTUALPTR(weapdef, AWeapon, CheckAddToSlots)
+		{
+			VMValue param = weapdef;
+			int slot = -1, slotpriority;
+			VMReturn rets[]{ &slot, &slotpriority };
+			VMCall(func, &param, 1, rets, 2);
+
+			if (slot >= 0 && slot < NUM_WEAPON_SLOTS)
 			{
-				FWeaponSlot::WeaponInfo info = { cls, weapdef->SlotPriority };
+				FWeaponSlot::WeaponInfo info = { cls, slotpriority };
 				Slots[slot].Weapons.Push(info);
 			}
 		}

src/g_inventory/a_weapons.h

@@ -148,8 +148,6 @@ public:
 	int BobStyle;							// [XA] Bobbing style. Defines type of bobbing (e.g. Normal, Alpha)  (visual only so no need to be a double)
 	float BobSpeed;							// [XA] Bobbing speed. Defines how quickly a weapon bobs.
 	float BobRangeX, BobRangeY;				// [XA] Bobbing range. Defines how far a weapon bobs in either direction.
-	int SlotNumber;
-	int SlotPriority;
 
 	// In-inventory instance variables
 	TObjPtr<AInventory*> Ammo1, Ammo2;
@@ -159,6 +157,7 @@ public:
 	bool GivenAsMorphWeapon;				// *** only accessed from ZScript.
 
 	bool bAltFire;							// *** only accessed from ZScript. Set when this weapon's alternate fire is used.
+	bool bDehAmmo;
 
 	virtual void MarkPrecacheSounds() const;
 	
@@ -202,8 +201,7 @@ enum
 	WIF_STAFF2_KICKBACK =	0x00002000, // the powered-up Heretic staff has special kickback
 	WIF_NOAUTOAIM =			0x00004000, // this weapon never uses autoaim (useful for ballistic projectiles)
 	WIF_MELEEWEAPON =		0x00008000,	// melee weapon. Used by bots and monster AI.
-	WIF_DEHAMMO	=			0x00010000,	// Uses Doom's original amount of ammo for the respective attack functions so that old DEHACKED patches work as intended.
-										// AmmoUse1 will be set to the first attack's ammo use so that checking for empty weapons still works
+	//WIF_DEHAMMO	=			0x00010000,	
 	WIF_NODEATHDESELECT =	0x00020000, // Don't jump to the Deselect state when the player dies
 	WIF_NODEATHINPUT =		0x00040000, // The weapon cannot be fired/reloaded/whatever when the player is dead
 	WIF_CHEATNOTWEAPON	=	0x08000000,	// Give cheat considers this not a weapon (used by Sigil)

src/scripting/thingdef_properties.cpp

@@ -1203,15 +1203,6 @@ DEFINE_CLASS_PROPERTY(bobstyle, S, Weapon)
 	defaults->BobStyle = styles[match];
 }
 
-//==========================================================================
-//
-//==========================================================================
-DEFINE_CLASS_PROPERTY(slotpriority, F, Weapon)
-{
-	PROP_DOUBLE_PARM(i, 0);
-	defaults->SlotPriority = int(i*65536);
-}
-
 //==========================================================================
 //
 //==========================================================================

wadsrc/static/zscript/inventory/weapons.txt

@@ -31,8 +31,10 @@ class Weapon : StateProvider native
 	native int Crosshair;							// 0 to use player's crosshair
 	native bool GivenAsMorphWeapon;
 	native bool bAltFire;							// Set when this weapon's alternate fire is used.
-	native readonly bool bDehAmmo;
-	native readonly int SlotNumber;
+	native readonly bool bDehAmmo;					// Uses Doom's original amount of ammo for the respective attack functions so that old DEHACKED patches work as intended.
+													// AmmoUse1 will be set to the first attack's ammo use so that checking for empty weapons still works
+	meta int SlotNumber;
+	meta int SlotPriority;
 	
 	property AmmoGive: AmmoGive1;
 	property AmmoGive1: AmmoGive1;
@@ -55,6 +57,7 @@ class Weapon : StateProvider native
 	property BobRangeX: BobRangeX;
 	property BobRangeY: BobRangeY;
 	property SlotNumber: SlotNumber;
+	property SlotPriority: SlotPriority;
 
 	Default
 	{
@@ -74,6 +77,16 @@ class Weapon : StateProvider native
 		SHTG E 0 A_Light0;
 		Stop;
 	}
+
+	
+	virtual int, int CheckAddToSlots()
+	{
+		if (GetReplacement(GetClass()) == null && !bPowered_Up)
+		{
+			return SlotNumber, SlotPriority*65536;
+		}
+		return -1, 0;
+	}
 	
 	virtual State GetReadyState ()
 	{