Improved the implementation of HOOK_INVENWIELD

* it now runs for the player and NPCs when removing equipped items.
* added an additional argument.

Fixed drop_obj script function not removing the equipped armor properly
for the player and party members.

artifacts/scripting/hookscripts.txt

@@ -431,7 +431,7 @@ int     ret1 - Override setting (-1 - use engine handler, any other value - prev
 
 HOOK_INVENWIELD (hs_invenwield.int)
 
-Runs before wielding or unwielding an armor or a weapon by a critter (except when using inventory by PC).
+Runs before causing a critter or the player to wield/unwield an armor or a weapon (except when using the inventory by PC).
 An example usage would be to change critter art depending on armor being used or to dynamically customize weapon animations.
 NOTE: when replacing a previously wielded armor or weapon, the unwielding hook will not be executed.
 If you need to rely on this, try checking if armor/weapon is already equipped when wielding hook is executed.
@@ -440,5 +440,6 @@ Critter arg1 - critter
 Obj     arg2 - item being wielded or unwielded (weapon/armor)
 int     arg3 - slot (INVEN_TYPE_*)
 int     arg4 - 1 when wielding, 0 when unwielding
+int     arg5 - 1 when removing an equipped item from inventory, 0 otherwise
 
 int     ret1 - overrides hard-coded handler (-1 - use engine handler, any other value - override) - NOT RECOMMENDED

sfall/BugFixes.cpp

@@ -3,6 +3,7 @@
 #include "BugFixes.h"
 #include "Define.h"
 #include "FalloutEngine.h"
+#include "HookScripts.h"
 #include "LoadGameHook.h"
 #include "ScriptExtender.h"
 
@@ -382,7 +383,7 @@ nextArmor:
 		call inven_worn_;
 		test eax, eax;
 		jz   noArmor;
-		and  byte ptr [eax + 0x27], 0xFB; // Unset the flag of equipped armor
+		and  byte ptr [eax + 0x27], 0xFB; // Unset flag of equipped armor (~Worn >> 24)
 		jmp  nextArmor;
 noArmor:
 		mov  eax, esi;
@@ -398,7 +399,7 @@ nextArmor:
 		call inven_worn_;
 		test eax, eax;
 		jz   end;
-		and  byte ptr [eax + 0x27], 0xFB; // Unset flag of equipped armor
+		and  byte ptr [eax + 0x27], 0xFB; // Unset flag of equipped armor (~Worn >> 24)
 		jmp  nextArmor;
 end:
 		retn;
@@ -420,11 +421,15 @@ skip:
 		jz   dudeFix;
 		test eax, eax;
 		jz   end;
+		// fix for party member
+		call InvenUnwield_HookMove;    // run HOOK_INVENWIELD before moving item
+		push ebx;
 		mov  ecx, edx;
 		xor  ebx, ebx;                 // new armor
 		xchg eax, edx;                 // set: eax - source, edx - removed armor
-		call adjust_ac_;               // fix for party member
+		call adjust_ac_;
 		mov  edx, ecx;
+		pop  ebx;
 		xor  eax, eax;
 end:
 		retn;                          // must be eax = 0
@@ -432,7 +437,7 @@ dudeFix:
 		test eax, eax;
 		jz   equipped;                 // no armor
 		// additionally check flag of equipped armor for dude
-		test byte ptr [eax + 0x27], 0x4;
+		test byte ptr [eax + 0x27], 0x4; // Worn >> 24
 		jnz  equipped;
 		xor  eax, eax;
 equipped:
@@ -441,6 +446,29 @@ equipped:
 	}
 }
 
+static void __declspec(naked) obj_drop_hook() {
+	__asm {
+		test byte ptr [edx + 0x27], 0x7; // (Worn | Right_Hand | Left_Hand) >> 24
+		jz   skipHook;
+		call InvenUnwield_HookDrop;    // run HOOK_INVENWIELD before dropping item
+skipHook:
+		test byte ptr [edx + 0x27], 0x4; // Worn >> 24
+		jnz  fixArmorStat;
+		jmp  obj_remove_from_inven_;
+fixArmorStat:
+		call isPartyMember_; // and dude
+		test eax, eax;
+		jz   skip;
+		mov  eax, ecx;
+		xor  ebx, ebx;                 // new armor
+		call adjust_ac_;               // eax - source, edx - removed armor
+		mov  edx, esi;
+skip:
+		mov  eax, ecx;
+		jmp  obj_remove_from_inven_;
+	}
+}
+
 static void __declspec(naked) partyMemberIncLevels_hook() {
 	__asm {
 		mov  ebx, eax;                            // party member pointer
@@ -2422,6 +2450,8 @@ void BugFixesInit()
 		HookCall(0x45C49A, op_move_obj_inven_to_obj_hook);
 		SafeWrite16(0x45C496, 0x9090);
 		SafeWrite8(0x45C4A3, 0x75); // jmp > jnz
+		// Fix for drop_obj function
+		HookCall(0x49B965, obj_drop_hook);
 		dlogr(" Done", DL_INIT);
 	//}
 

sfall/FalloutEngine.cpp

@@ -99,7 +99,7 @@ DWORD* ptr_inven_scroll_dn_bid        = reinterpret_cast<DWORD*>(_inven_scroll_d
 DWORD* ptr_inven_scroll_up_bid        = reinterpret_cast<DWORD*>(_inven_scroll_up_bid);
 DWORD* ptr_inventry_message_file      = reinterpret_cast<DWORD*>(_inventry_message_file);
 DWORD* ptr_itemButtonItems            = reinterpret_cast<DWORD*>(_itemButtonItems);
-DWORD* ptr_itemCurrentItem            = reinterpret_cast<DWORD*>(_itemCurrentItem); // 0 - left, 1 - right
+long*  ptr_itemCurrentItem            = reinterpret_cast<long*>(_itemCurrentItem); // 0 - left, 1 - right
 DWORD* ptr_kb_lock_flags              = reinterpret_cast<DWORD*>(_kb_lock_flags);
 DWORD* ptr_last_buttons               = reinterpret_cast<DWORD*>(_last_buttons);
 DWORD* ptr_last_button_winID          = reinterpret_cast<DWORD*>(_last_button_winID);
@@ -524,6 +524,7 @@ const DWORD obj_lock_is_jammed_ = 0x49D410;
 const DWORD obj_new_sid_inst_ = 0x49AAC0;
 const DWORD obj_outline_object_ = 0x48C2B4;
 const DWORD obj_pid_new_ = 0x489C9C;
+const DWORD obj_remove_from_inven_ = 0x49B73C;
 const DWORD obj_remove_outline_ = 0x48C2F0;
 const DWORD obj_save_dude_ = 0x48D59C;
 const DWORD obj_scroll_blocking_at_ = 0x48BB44;

sfall/FalloutEngine.h

@@ -341,7 +341,7 @@ extern DWORD* ptr_inven_scroll_dn_bid;
 extern DWORD* ptr_inven_scroll_up_bid;
 extern DWORD* ptr_inventry_message_file;
 extern DWORD* ptr_itemButtonItems;
-extern DWORD* ptr_itemCurrentItem; // 0 - left, 1 - right
+extern long*  ptr_itemCurrentItem; // 0 - left, 1 - right
 extern DWORD* ptr_kb_lock_flags;
 extern DWORD* ptr_last_buttons;
 extern DWORD* ptr_last_button_winID;
@@ -756,6 +756,7 @@ extern const DWORD obj_new_;  // int aObj*<eax>, int aPid<ebx>
 extern const DWORD obj_new_sid_inst_;
 extern const DWORD obj_outline_object_;
 extern const DWORD obj_pid_new_;
+extern const DWORD obj_remove_from_inven_;
 extern const DWORD obj_remove_outline_;
 extern const DWORD obj_save_dude_;
 extern const DWORD obj_scroll_blocking_at_;

sfall/HookScripts.cpp

@@ -1254,17 +1254,45 @@ skip:
 	}
 }
 
-/* Common InvenWield hook */
-static bool InvenWieldHook_Script(int flag) {
-	argCount = 4;
-	args[3] = flag;  // invenwield flag
+/* Common InvenWield script hooks */
+static long __fastcall InvenWieldHook_Script(TGameObj* critter, TGameObj* item, long slot, long isWield, long isRemove) {
+	if (!isWield) {
+		// for the critter, the right slot is always the active slot
+		if (slot == INVEN_TYPE_LEFT_HAND && critter != *ptr_obj_dude) return 1;
+		// check the current active slot for the player
+		if (slot != INVEN_TYPE_WORN && critter == *ptr_obj_dude) {
+			long _slot = (slot != INVEN_TYPE_LEFT_HAND);
+			if (_slot != *ptr_itemCurrentItem) return 1; // item in non-active slot
+		}
+	}
+	BeginHook();
 
+	args[0] = (DWORD)critter;
+	args[1] = (DWORD)item;
+	args[2] = slot;
+	args[3] = isWield; // unwield/wield event
+	args[4] = isRemove;
+
+	argCount = 5;
+	RunHookScript(HOOK_INVENWIELD);
+
+	long result = (cRet == 0 || rets[0] == -1);
+	EndHook();
+
+	return result; // 1 - use engine handler
+}
+
+static __declspec(noinline) bool InvenWieldHook_ScriptPart(long isWield, long isRemove = 0) {
+	args[3] = isWield; // unwield/wield event
+	args[4] = isRemove;
+
+	argCount = 5;
 	RunHookScript(HOOK_INVENWIELD);
 
 	bool result = (cRet == 0 || rets[0] == -1);
 	EndHook();
 
-	return result; // True - use engine handler
+	return result; // true - use engine handler
 }
 
 static void __declspec(naked) InvenWieldFuncHook() {
@@ -1275,13 +1303,11 @@ static void __declspec(naked) InvenWieldFuncHook() {
 		mov args[8], ebx; // slot
 		pushad;
 	}
-
 	// right hand slot?
 	if (args[2] != INVEN_TYPE_RIGHT_HAND && ItemGetType((TGameObj*)args[1]) != item_type_armor) {
 		args[2] = INVEN_TYPE_LEFT_HAND;
 	}
-
-	InvenWieldHook_Script(1); // wield flag
+	InvenWieldHook_ScriptPart(1); // wield event
 
 	__asm {
 		test al, al;
@@ -1302,14 +1328,14 @@ static void __declspec(naked) InvenUnwieldFuncHook() {
 		mov args[8], edx; // slot
 		pushad;
 	}
-
 	// set slot
 	if (args[2] == 0) { // left hand slot?
 		args[2] = INVEN_TYPE_LEFT_HAND;
 	}
-	args[1] = (DWORD)GetItemPtrSlot((TGameObj*)args[0], args[2]); // get item
+	// get item
+	args[1] = (DWORD)GetItemPtrSlot((TGameObj*)args[0], args[2]);
 
-	InvenWieldHook_Script(0); // unwield flag
+	InvenWieldHook_ScriptPart(0); // unwield event
 
 	__asm {
 		test al, al;
@@ -1328,9 +1354,8 @@ static void __declspec(naked) CorrectFidForRemovedItemHook() {
 		mov args[0], eax; // critter
 		mov args[4], edx; // item
 		mov args[8], ebx; // item flag
-		pushad;
+		pushadc;
 	}
-
 	// set slot
 	if (args[2] & 0x2000000) {        // right hand slot
 		args[2] = INVEN_TYPE_RIGHT_HAND;
@@ -1339,20 +1364,117 @@ static void __declspec(naked) CorrectFidForRemovedItemHook() {
 	} else {
 		args[2] = INVEN_TYPE_WORN;    // armor slot
 	}
-
-	InvenWieldHook_Script(0); // unwield flag (armor by default)
-
+	InvenWieldHook_ScriptPart(0, 1); // unwield event (armor by default)
+	// engine handler is not overridden
 	__asm {
-		test al, al;
-		popad;
-		jz   skip;
+		popadc;
 		jmp  correctFidForRemovedItem_;
+	}
+}
+
+static void __declspec(naked) item_drop_all_hack() {
+	__asm {
+		push eax;
+		push 1;  // remove event
+		push 0;  // unwield event
+		mov  ecx, INVEN_TYPE_LEFT_HAND;
+		test ah, 0x1; // Left_Hand >> 24
+		jnz  skip;
+		test ah, 0x4; // Worn >> 24
+		setz cl; // set INVEN_TYPE_WORN or INVEN_TYPE_RIGHT_HAND
 skip:
-		mov  eax, -1;
+		push ecx;      // slot
+		mov  edx, esi; // item
+		mov  ecx, edi; // critter
+		call InvenWieldHook_Script;
+		mov  [esp + 0x40 - 0x2C + 8], eax; // itemIsEquipped (hook return result)
+		pop  eax;
 		retn;
 	}
 }
 
+// called from bugfixes for obj_drop_
+void __declspec(naked) InvenUnwield_HookDrop() { // ecx - critter, edx - item
+	__asm {
+		pushadc;
+		mov  eax, INVEN_TYPE_LEFT_HAND;
+		test byte ptr [edx + 0x27], 0x1; // Left_Hand >> 24
+		jnz  isLeft;
+		test byte ptr [edx + 0x27], 0x4; // Worn >> 24
+		setz al;  // set INVEN_TYPE_WORN or INVEN_TYPE_RIGHT_HAND
+isLeft:
+		push 1;   // remove event
+		push 0;   // unwield event
+		push eax; // slot
+		call InvenWieldHook_Script; // ecx - critter, edx - item
+		// engine handler is not overridden
+		popadc;
+		retn;
+	}
+}
+
+// called from bugfixes for op_move_obj_inven_to_obj_
+void __declspec(naked) InvenUnwield_HookMove() { // eax - item, edx - critter
+	__asm {
+		pushadc;
+		mov  ecx, edx;
+		mov  edx, eax;
+		push 1;   // remove event
+		xor  eax, eax;
+		push eax; // unwield event
+		push eax; // slot
+		call InvenWieldHook_Script; // ecx - critter, edx - item
+		// engine handler is not overridden
+		popadc;
+		retn;
+	}
+}
+
+// called when unwelding dude weapon and armor
+static void __declspec(naked) op_move_obj_inven_to_obj_hook() {
+	__asm {
+		cmp  eax, ds:[_obj_dude];
+		je   runHook;
+		jmp  item_move_all_;
+runHook:
+		push eax;
+		push edx;
+		mov  ecx, eax; // keep source
+		mov  edx, ds:[_itemCurrentItem]; // get player's active slot
+		test edx, edx;
+		jz   left;
+		call inven_right_hand_;
+		jmp  skip;
+left:
+		call inven_left_hand_;
+skip:
+		test eax, eax;
+		jz   noWeapon;
+		push 1; // remove event
+		push 0; // unwield event
+		mov  ebx, INVEN_TYPE_LEFT_HAND;
+		sub  ebx, edx;
+		push ebx;      // slot: INVEN_TYPE_LEFT_HAND or INVEN_TYPE_RIGHT_HAND
+		mov  edx, eax; // weapon
+		call InvenWieldHook_Script; // ecx - source
+		// engine handler is not overridden
+noWeapon:
+		mov  edx, [esp + 0x30 - 0x20 + 12]; // armor
+		test edx, edx;
+		jz   noArmor;
+		xor  eax, eax;
+		push 1;   // remove event
+		push eax; // unwield event
+		push eax; // slot: INVEN_TYPE_WORN
+		call InvenWieldHook_Script; // ecx - source
+		// engine handler is not overridden
+noArmor:
+		pop  edx;
+		pop  eax;
+		jmp  item_move_all_;
+	}
+}
+
 DWORD _stdcall GetHSArgCount() {
 	return argCount;
 }
@@ -1605,6 +1727,8 @@ static void HookScriptInit2() {
 	HookCall(0x495F0B, InvenUnwieldFuncHook); // partyMemberCopyLevelInfo_
 	HookCall(0x45680C, CorrectFidForRemovedItemHook); // op_rm_obj_from_inven_
 	HookCall(0x45C4EA, CorrectFidForRemovedItemHook); // op_move_obj_inven_to_obj_
+	HookCall(0x45C4F6, op_move_obj_inven_to_obj_hook);
+	MakeCall(0x4778AF, item_drop_all_hack, 3);
 
 	__asm {
 		xor  edx, edx

sfall/HookScripts.h

@@ -63,6 +63,10 @@ void HookScriptClear();
 
 extern DWORD InitingHookScripts;
 extern int __fastcall AmmoCostHook_Script(DWORD hookType, TGameObj* weapon, DWORD &rounds);
-void _stdcall MouseClickHook(DWORD button, bool pressed);
-DWORD _stdcall KeyPressHook(DWORD dxKey, bool pressed, DWORD vKey);
 void _stdcall RunHookScriptsAtProc(DWORD procId);
+
+DWORD _stdcall KeyPressHook(DWORD dxKey, bool pressed, DWORD vKey);
+void _stdcall MouseClickHook(DWORD button, bool pressed);
+
+void InvenUnwield_HookDrop();
+void InvenUnwield_HookMove();