Fix price enchantment price calculation to use the correct item count

CHANGELOG.md

@@ -62,6 +62,7 @@
     Bug #7415: Unbreakable lock discrepancies
     Bug #7428: AutoCalc flag is not used to calculate enchantment costs
     Bug #7459: Icons get stacked on the cursor when picking up multiple items simultaneously
+    Bug #7472: Crash when enchanting last projectiles
     Feature #3537: Shader-based water ripples
     Feature #5492: Let rain and snow collide with statics
     Feature #6447: Add LOD support to Object Paging

apps/openmw/mwgui/enchantingdialog.cpp

@@ -357,9 +357,7 @@ namespace MWGui
             }
         }
 
-        int result = mEnchanting.create();
-
-        if (result == 1)
+        if (mEnchanting.create())
         {
             MWBase::Environment::get().getWindowManager()->playSound(ESM::RefId::stringRefId("enchant success"));
             MWBase::Environment::get().getWindowManager()->messageBox("#{sEnchantmentMenu12}");

apps/openmw/mwmechanics/enchanting.cpp

@@ -104,13 +104,13 @@ namespace MWMechanics
         const ESM::RefId& newItemId
             = mOldItemPtr.getClass().applyEnchantment(mOldItemPtr, enchantmentPtr->mId, getGemCharge(), mNewItemName);
 
+        if (!mSelfEnchanting)
+            payForEnchantment(count);
+
         // Add the new item to player inventory and remove the old one
         store.remove(mOldItemPtr, count);
         store.add(newItemId, count);
 
-        if (!mSelfEnchanting)
-            payForEnchantment();
-
         return true;
     }
 
@@ -277,7 +277,7 @@ namespace MWMechanics
         return getEffectiveEnchantmentCastCost(static_cast<float>(baseCost), player);
     }
 
-    int Enchanting::getEnchantPrice() const
+    int Enchanting::getEnchantPrice(int count) const
     {
         if (mEnchanter.isEmpty())
             return 0;
@@ -289,7 +289,7 @@ namespace MWMechanics
                                    ->mValue.getFloat();
         int price = MWBase::Environment::get().getMechanicsManager()->getBarterOffer(
             mEnchanter, static_cast<int>(getEnchantPoints() * priceMultipler), true);
-        price *= getEnchantItemsCount() * getTypeMultiplier();
+        price *= count * getTypeMultiplier();
         return std::max(1, price);
     }
 
@@ -390,15 +390,16 @@ namespace MWMechanics
         return 1.f;
     }
 
-    void Enchanting::payForEnchantment() const
+    void Enchanting::payForEnchantment(int count) const
     {
         const MWWorld::Ptr& player = getPlayer();
         MWWorld::ContainerStore& store = player.getClass().getContainerStore(player);
 
-        store.remove(MWWorld::ContainerStore::sGoldId, getEnchantPrice());
+        int price = getEnchantPrice(count);
+        store.remove(MWWorld::ContainerStore::sGoldId, price);
 
         // add gold to NPC trading gold pool
         CreatureStats& enchanterStats = mEnchanter.getClass().getCreatureStats(mEnchanter);
-        enchanterStats.setGoldPool(enchanterStats.getGoldPool() + getEnchantPrice());
+        enchanterStats.setGoldPool(enchanterStats.getGoldPool() + price);
     }
 }

apps/openmw/mwmechanics/enchanting.hpp

@@ -27,6 +27,11 @@ namespace MWMechanics
         int mWeaponType;
 
         const ESM::Enchantment* getRecord(const ESM::Enchantment& newEnchantment) const;
+        int getBaseCastCost() const; // To be saved in the enchantment's record
+        int getEnchantItemsCount() const;
+        float getTypeMultiplier() const;
+        void payForEnchantment(int count) const;
+        int getEnchantPrice(int count) const;
 
     public:
         Enchanting();
@@ -42,18 +47,14 @@ namespace MWMechanics
         void nextCastStyle(); // Set enchant type to next possible type (for mOldItemPtr object)
         int getCastStyle() const;
         float getEnchantPoints(bool precise = true) const;
-        int getBaseCastCost() const; // To be saved in the enchantment's record
         int getEffectiveCastCost()
             const; // Effective cost taking player Enchant skill into account, used for preview purposes in the UI
-        int getEnchantPrice() const;
+        int getEnchantPrice() const { return getEnchantPrice(getEnchantItemsCount()); }
         int getMaxEnchantValue() const;
         int getGemCharge() const;
         int getEnchantChance() const;
-        int getEnchantItemsCount() const;
-        float getTypeMultiplier() const;
         bool soulEmpty() const; // Return true if empty
         bool itemEmpty() const; // Return true if empty
-        void payForEnchantment() const;
     };
 }
 #endif