Convert constant effect equipment slots to refnums

apps/openmw/mwworld/cellstore.cpp

@@ -264,8 +264,18 @@ namespace
         }
         else if (state.mVersion <= ESM::MaxOldCreatureStatsFormatVersion)
         {
-            if constexpr (std::is_same_v<T, ESM::Creature> || std::is_same_v<T, ESM::NPC>)
+            if constexpr (std::is_same_v<T, ESM::Creature>)
+                MWWorld::convertStats(state.mCreatureStats);
+            else if constexpr (std::is_same_v<T, ESM::NPC>)
+            {
                 MWWorld::convertStats(state.mCreatureStats);
+                MWWorld::convertEnchantmentSlots(state.mCreatureStats, state.mInventory);
+            }
+        }
+        else if (state.mVersion <= ESM::MaxActiveSpellSlotIndexFormatVersion)
+        {
+            if constexpr (std::is_same_v<T, ESM::NPC>)
+                MWWorld::convertEnchantmentSlots(state.mCreatureStats, state.mInventory);
         }
 
         if (state.mRef.mRefNum.hasContentFile())

apps/openmw/mwworld/magiceffects.cpp

@@ -11,6 +11,7 @@
 #include <components/esm3/npcstate.hpp>
 
 #include "../mwbase/environment.hpp"
+#include "../mwworld/worldmodel.hpp"
 
 #include "../mwmechanics/magiceffects.hpp"
 
@@ -101,13 +102,16 @@ namespace MWWorld
             }
             creatureStats.mActiveSpells.mSpells.emplace_back(params);
         }
-        std::multimap<ESM::RefId, int> equippedItems;
+        std::multimap<ESM::RefId, ESM::RefNum> equippedItems;
         for (std::size_t i = 0; i < inventory.mItems.size(); ++i)
         {
-            const ESM::ObjectState& item = inventory.mItems[i];
+            ESM::ObjectState& item = inventory.mItems[i];
             auto slot = inventory.mEquipmentSlots.find(i);
             if (slot != inventory.mEquipmentSlots.end())
-                equippedItems.emplace(item.mRef.mRefID, slot->second);
+            {
+                MWBase::Environment::get().getWorldModel()->assignSaveFileRefNum(item.mRef);
+                equippedItems.emplace(item.mRef.mRefID, item.mRef.mRefNum);
+            }
         }
         for (const auto& [id, oldMagnitudes] : inventory.mPermanentMagicEffectMagnitudes)
         {
@@ -161,7 +165,7 @@ namespace MWWorld
             auto [begin, end] = equippedItems.equal_range(id);
             for (auto it = begin; it != end; ++it)
             {
-                params.mItem = { static_cast<unsigned int>(it->second), 0 };
+                params.mItem = it->second;
                 creatureStats.mActiveSpells.mSpells.emplace_back(params);
             }
         }
@@ -229,4 +233,28 @@ namespace MWWorld
         for (auto& setting : creatureStats.mAiSettings)
             setting.mMod = 0.f;
     }
+
+    // Versions 17-27 wrote an equipment slot index to mItem
+    void convertEnchantmentSlots(ESM::CreatureStats& creatureStats, ESM::InventoryState& inventory)
+    {
+        for (auto& activeSpell : creatureStats.mActiveSpells.mSpells)
+        {
+            if (!activeSpell.mItem.isSet())
+                continue;
+            if (activeSpell.mFlags & ESM::ActiveSpells::Flag_Equipment)
+            {
+                auto slotIndex = activeSpell.mItem.mIndex;
+                auto slot = std::find_if(inventory.mEquipmentSlots.begin(), inventory.mEquipmentSlots.end(),
+                    [=](const auto& entry) { return entry.second == slotIndex; });
+                if (slot != inventory.mEquipmentSlots.end() && slot->first < inventory.mItems.size())
+                {
+                    ESM::CellRef& ref = inventory.mItems[slot->first].mRef;
+                    MWBase::Environment::get().getWorldModel()->assignSaveFileRefNum(ref);
+                    activeSpell.mItem = ref.mRefNum;
+                    continue;
+                }
+            }
+            activeSpell.mItem = {};
+        }
+    }
 }

apps/openmw/mwworld/magiceffects.hpp

@@ -14,6 +14,8 @@ namespace MWWorld
         ESM::CreatureStats& creatureStats, ESM::InventoryState& inventory, ESM::NpcStats* npcStats = nullptr);
 
     void convertStats(ESM::CreatureStats& creatureStats);
+
+    void convertEnchantmentSlots(ESM::CreatureStats& creatureStats, ESM::InventoryState& inventory);
 }
 
 #endif

apps/openmw/mwworld/player.cpp

@@ -317,7 +317,12 @@ namespace MWWorld
                 convertMagicEffects(
                     player.mObject.mCreatureStats, player.mObject.mInventory, &player.mObject.mNpcStats);
             else if (reader.getFormatVersion() <= ESM::MaxOldCreatureStatsFormatVersion)
+            {
                 convertStats(player.mObject.mCreatureStats);
+                convertEnchantmentSlots(player.mObject.mCreatureStats, player.mObject.mInventory);
+            }
+            else if (reader.getFormatVersion() <= ESM::MaxActiveSpellSlotIndexFormatVersion)
+                convertEnchantmentSlots(player.mObject.mCreatureStats, player.mObject.mInventory);
 
             if (!player.mObject.mEnabled)
             {

apps/openmw/mwworld/ptrregistry.hpp

@@ -56,6 +56,17 @@ namespace MWWorld
             }
         }
 
+        // For fixing old saves
+        void assign(ESM::CellRef& ref)
+        {
+            if (!ref.mRefNum.isSet())
+            {
+                CellRef temp(ref);
+                temp.getOrAssignRefNum(mLastGenerated);
+                ref.mRefNum = temp.getRefNum();
+            }
+        }
+
     private:
         std::size_t mRevision = 0;
         std::unordered_map<ESM::RefNum, Ptr> mIndex;

apps/openmw/mwworld/worldmodel.hpp

@@ -81,6 +81,8 @@ namespace MWWorld
 
         void deregisterLiveCellRef(const LiveCellRefBase& ref) noexcept { mPtrRegistry.remove(ref); }
 
+        void assignSaveFileRefNum(ESM::CellRef& ref) { mPtrRegistry.assign(ref); }
+
         template <typename Fn>
         void forEachLoadedCellStore(Fn&& fn)
         {

components/esm3/activespells.cpp

@@ -168,15 +168,8 @@ namespace ESM
                         esm.getHNT(params.mFlags, "FLAG");
                     }
                     if (esm.peekNextSub("ITEM"))
-                    {
-                        if (format <= MaxActiveSpellSlotIndexFormatVersion)
-                            // Previous versions saved slot index in this record.
-                            // Ignore these values as we can't use them
-                            esm.getFormId(true, "ITEM");
-                        else
                         params.mItem = esm.getFormId(true, "ITEM");
                 }
-                }
                 if (esm.isNextSub("WORS"))
                 {
                     esm.getHT(params.mWorsenings);