Code changes to the previous commit

Changed HOOK_CANUSEWEAPON to run for both the player and NPCs.
Updated gl_npcarmor script.

artifacts/mods/gl_npcarmor.ssl

@@ -65,7 +65,7 @@ procedure check_weapon_change(variable critter, variable weapon, variable isWiel
             weaponAnimList := npc["WeaponAnims"];
             if (weaponAnimList != 0) then begin
                foreach (i in string_split(weaponAnimList, ",")) begin
-                  if (newWeaponAnim == atoi(i)) then return -1; // can use (engine default)
+                  if (newWeaponAnim == atoi(i) and not(weapon_is_unusable(weapon))) then return -1; // can use (engine default)
                end
             end
             return 0; // can't use
@@ -226,10 +226,10 @@ end
 procedure canuseweapon_handler begin
    variable critter, canWield;
    critter := get_sfall_arg;
-   //if (critter) then begin
+   if (critter != dude_obj) then begin
       canWield := check_weapon_change(critter, get_sfall_arg, true);
       // override result
       set_sfall_arg(3, canWield);
       set_sfall_return(canWield);
-   //end
+   end
 end

artifacts/scripting/headers/sfall.h

@@ -289,9 +289,11 @@
 // checks if the specified PID number exists in the list of registered protos
 #define check_pid(pid)                                  (get_proto_data(pid, 0) != -1)
 
-// sets the status of a broken weapon that cannot be used in combat (the hand slot will not be available for use)
-#define set_broken_weapon_state_on(item)                set_object_data(item, OBJ_DATA_MISC_FLAGS, get_object_data(item, OBJ_DATA_MISC_FLAGS) bwor  0x00000010)
-#define set_broken_weapon_state_off(item)               set_object_data(item, OBJ_DATA_MISC_FLAGS, get_object_data(item, OBJ_DATA_MISC_FLAGS) bwand 0xFFFFFFEF)
+// sets the status of an unusable weapon that cannot be used in combat
+// use the HOOK_CANUSEWEAPON hook with weapon_is_unusable macro to override the engine value
+#define set_weapon_unusable(item)                       set_object_data(item, OBJ_DATA_MISC_FLAGS, get_object_data(item, OBJ_DATA_MISC_FLAGS) bwor  0x00000010)
+#define set_weapon_usable(item)                         set_object_data(item, OBJ_DATA_MISC_FLAGS, get_object_data(item, OBJ_DATA_MISC_FLAGS) bwand 0xFFFFFFEF)
+#define weapon_is_unusable(item)                        (get_object_data(item, OBJ_DATA_MISC_FLAGS) bwand 0x00000010)
 
 
 /* SFALL_FUNCX MACROS */

artifacts/scripting/hookscripts.md

@@ -897,13 +897,14 @@ Item    ret0 - overrides the chosen best weapon
 
 #### `HOOK_CANUSEWEAPON (hs_canuseweapon.int)`
 
-Run when the AI checks whether it can use a weapon.
-This mostly happens when NPCs try to find weapons in their inventory or on the map.
+Run when the AI checks whether it can use a weapon, or when the game checks whether the player can use a weapon.
+For AI, this mostly happens when NPCs try to find weapons in their inventory or on the map.
+For the player, this happens when the game redraws the interface bar.
 
 ```
 Critter arg0 - the critter doing the check
-Item    arg1 - the weapon being checked
-int     arg2 - attack type (see ATKTYPE_* constants)
+Item    arg1 - the item being checked
+int     arg2 - attack type (see ATKTYPE_* constants), or -1 for dude_obj
 int     arg3 - original result of engine function: 1 - can use, 0 - can't use
 
 int     ret0 - overrides the result of engine function. Any non-zero value allows using the weapon

sfall/FalloutEngine/FunctionOffsets_def.h

@@ -616,6 +616,7 @@ FUNC(calculateColor_,                 0x4C72B4)
 FUNC(calloc_,                         0x4EAFEC)
 FUNC(can_see_,                        0x412BEC)
 FUNC(can_talk_to_,                    0x413420)
+FUNC(can_use_weapon_,                 0x477F3C)
 FUNC(cget_,                           0x4F2250)
 FUNC(cget_string_,                    0x4F0EA1)
 FUNC(cgetw_,                          0x4F2E5B)

sfall/Modules/HookScripts/CombatHs.cpp

@@ -626,17 +626,17 @@ static bool __stdcall CanUseWeaponHook_Script(bool result, fo::GameObject* sourc
 	args[0] = (DWORD)source;
 	args[1] = (DWORD)weapon;
 	args[2] = hitMode;
-	args[3] = 0 | result;
+	args[3] = result;
 
 	RunHookScript(HOOK_CANUSEWEAPON);
 
-	if (cRet > 0) result = rets[0] ? true : false;
+	if (cRet > 0) result = (rets[0]) ? true : false;
 
 	EndHook();
 	return result; // only 0 and 1
 }
 
-static void __declspec(naked) CanUseWeaponHook() {
+static void __declspec(naked) AICanUseWeaponHook() {
 	__asm {
 		push ecx;
 		push ebx; // hitMode
@@ -645,7 +645,25 @@ static void __declspec(naked) CanUseWeaponHook() {
 		call fo::funcoffs::ai_can_use_weapon_;
 		push eax; // result
 		call CanUseWeaponHook_Script;
-		and  eax, 1;
+		//and  eax, 1;
+		pop  ecx;
+		retn;
+	}
+}
+
+static void __declspec(naked) CanUseWeaponHook() {
+	__asm {
+		push ecx;
+		push edx;
+		push -1;  // hitMode (indefinite)
+		push eax; // weapon
+		push ds:[FO_VAR_obj_dude]; // source
+		call fo::funcoffs::can_use_weapon_; // 1 - can't use
+		xor  al, 1;
+		push eax; // result
+		call CanUseWeaponHook_Script;
+		xor  al, 1; // invert
+		pop  edx;
 		pop  ecx;
 		retn;
 	}
@@ -750,11 +768,12 @@ void Inject_BestWeaponHook() {
 }
 
 void Inject_CanUseWeaponHook() {
-	HookCalls(CanUseWeaponHook, {
+	HookCalls(AICanUseWeaponHook, {
 		0x429A1B, // ai_search_inven_weap_
 		0x429CF2, // ai_search_environ_
 		0x429E1C  // ai_pick_hit_mode_
 	});
+	HookCalls(CanUseWeaponHook, { 0x45F05E, 0x45F1C1, 0x45F203, 0x45F36A }); // intface_update_items_
 }
 
 void InitCombatHookScripts() {

sfall/Modules/Inventory.cpp

@@ -595,25 +595,6 @@ static void __declspec(naked) do_move_timer_hack() {
 	}
 }
 
-static void __declspec(naked) can_use_weapon_hook() {
-	static const DWORD can_use_weapon_Ret = 0x477F9F;
-	using namespace fo;
-	using namespace fo::Fields;
-	__asm {
-		call fo::funcoffs::item_get_type_;
-		cmp  eax, item_type_weapon;
-		je   checkFlag;
-		retn; // eax - type
-checkFlag:
-		test dword ptr [edx + miscFlags], CantUse;
-		jnz  cantUse;
-		retn; // eax - type
-cantUse:
-		add esp, 4;
-		jmp can_use_weapon_Ret;
-	}
-}
-
 static int invenApCost, invenApCostDef;
 static char invenApQPReduction;
 
@@ -758,11 +739,6 @@ void Inventory::init() {
 	// Note: the flag is not checked for the metarule(METARULE_INVEN_UNWIELD_WHO, x) function
 	HookCall(0x45B0CE, op_inven_unwield_hook); // with fix to update interface slot after unwielding
 	HookCall(0x45693C, op_wield_obj_critter_hook);
-
-	// Add an additional "Can't Use" flag to the misc flags of item objects (offset 0x0038)
-	// Misc Flags:
-	// 0x00000010 - Can't Use (makes the weapon object unusable in combat)
-	HookCall(0x477F4C, can_use_weapon_hook);
 }
 
 void Inventory::InvokeAdjustFid(long fid) {

sfall/Modules/SubModules/CombatBlock.cpp

@@ -60,6 +60,57 @@ end:
 	}
 }
 
+static void __declspec(naked) ai_can_use_weapon_hack() {
+	using namespace fo;
+	using namespace Fields;
+	__asm {
+		test dword ptr [esi + miscFlags], CantUse;
+		jnz  cantUse;
+		mov  eax, [edi + damageFlags];
+		retn;
+cantUse:
+		mov  al, 0xFF;
+		retn;
+	}
+}
+
+static void __declspec(naked) can_use_weapon_hook() {
+	static const DWORD cant_use_weapon_Ret = 0x477F9F;
+	using namespace fo;
+	using namespace Fields;
+	__asm {
+		call fo::funcoffs::item_get_type_;
+		cmp  eax, item_type_weapon;
+		je   checkFlag;
+		retn; // eax - type
+checkFlag:
+		test dword ptr [edx + miscFlags], CantUse;
+		jnz  cantUse;
+		retn; // eax - type
+cantUse:
+		add  esp, 4;
+		jmp  cant_use_weapon_Ret;
+	}
+}
+
+// Note: in ai_try_attack_, the attacker will not be able to change unusable weapon, as it happens with crippled arms
+static void __declspec(naked) combat_check_bad_shot_hack() {
+	static const DWORD combat_check_bad_shot_Ret = 0x42673A;
+	using namespace fo;
+	using namespace Fields;
+	__asm {
+		test dword ptr [ecx + miscFlags], CantUse;
+		jnz  cantUse;
+		mov  eax, [esi + damageFlags];
+		test al, DAM_CRIP_ARM_LEFT;
+		retn;
+cantUse:
+		mov  eax, 4; // result same as TargetDead
+		add  esp, 4;
+		jmp  combat_check_bad_shot_Ret;
+	}
+}
+
 void __stdcall CombatBlock::SetBlockCombat(long toggle) {
 	combatDisabled = toggle != 0;
 }
@@ -67,6 +118,13 @@ void __stdcall CombatBlock::SetBlockCombat(long toggle) {
 void CombatBlock::init() {
 	HookCall(0x45F626, intface_use_item_hook); // jnz hook
 	HookCall(0x4432A6, game_handle_input_hook);
+
+	// Add an additional "Can't Use" flag to the misc flags of item objects (offset 0x0038)
+	// Misc Flags:
+	// 0x00000010 - Can't Use (makes the weapon object unusable in combat)
+	HookCall(0x477F4C, can_use_weapon_hook);
+	MakeCall(0x4298F4, ai_can_use_weapon_hack);
+	MakeCall(0x426669, combat_check_bad_shot_hack);
 }
 
 }