Use CRTP to define CustomData clone function

apps/openmw/mwclass/container.cpp

@@ -46,11 +46,6 @@ namespace MWClass
         mStore.readState(inventory);
     }
 
-    std::unique_ptr<MWWorld::CustomData> ContainerCustomData::clone() const
-    {
-        return std::make_unique<ContainerCustomData>(*this);
-    }
-
     ContainerCustomData& ContainerCustomData::asContainerCustomData()
     {
         return *this;

apps/openmw/mwclass/container.hpp

@@ -13,15 +13,13 @@ namespace ESM
 
 namespace MWClass
 {
-    class ContainerCustomData : public MWWorld::CustomData
+    class ContainerCustomData : public MWWorld::TypedCustomData<ContainerCustomData>
     {
         MWWorld::ContainerStore mStore;
     public:
         ContainerCustomData(const ESM::Container& container, MWWorld::CellStore* cell);
         ContainerCustomData(const ESM::InventoryState& inventory);
 
-        std::unique_ptr<MWWorld::CustomData> clone() const override;
-
         ContainerCustomData& asContainerCustomData() override;
         const ContainerCustomData& asContainerCustomData() const override;
 

apps/openmw/mwclass/creature.cpp

@@ -51,7 +51,7 @@ namespace
 namespace MWClass
 {
 
-    class CreatureCustomData : public MWWorld::CustomData
+    class CreatureCustomData : public MWWorld::TypedCustomData<CreatureCustomData>
     {
     public:
         MWMechanics::CreatureStats mCreatureStats;
@@ -62,8 +62,6 @@ namespace MWClass
         CreatureCustomData(const CreatureCustomData& other);
         CreatureCustomData(CreatureCustomData&& other) noexcept = default;
 
-        std::unique_ptr<MWWorld::CustomData> clone() const override;
-
         CreatureCustomData& asCreatureCustomData() override
         {
             return *this;
@@ -81,11 +79,6 @@ namespace MWClass
     {
     }
 
-    std::unique_ptr<MWWorld::CustomData> CreatureCustomData::clone() const
-    {
-        return std::make_unique<CreatureCustomData>(*this);
-    }
-
     const Creature::GMST& Creature::getGmst()
     {
         static GMST gmst;

apps/openmw/mwclass/creaturelevlist.cpp

@@ -10,15 +10,13 @@
 
 namespace MWClass
 {
-    class CreatureLevListCustomData : public MWWorld::CustomData
+    class CreatureLevListCustomData : public MWWorld::TypedCustomData<CreatureLevListCustomData>
     {
     public:
         // actorId of the creature we spawned
         int mSpawnActorId;
         bool mSpawn; // Should a new creature be spawned?
 
-        std::unique_ptr<MWWorld::CustomData> clone() const override;
-
         CreatureLevListCustomData& asCreatureLevListCustomData() override
         {
             return *this;
@@ -29,11 +27,6 @@ namespace MWClass
         }
     };
 
-    std::unique_ptr<MWWorld::CustomData> CreatureLevListCustomData::clone() const
-    {
-        return std::make_unique<CreatureLevListCustomData>(*this);
-    }
-
     std::string CreatureLevList::getName (const MWWorld::ConstPtr& ptr) const
     {
         return "";

apps/openmw/mwclass/door.cpp

@@ -31,13 +31,11 @@
 
 namespace MWClass
 {
-    class DoorCustomData : public MWWorld::CustomData
+    class DoorCustomData : public MWWorld::TypedCustomData<DoorCustomData>
     {
     public:
         MWWorld::DoorState mDoorState = MWWorld::DoorState::Idle;
 
-        std::unique_ptr<MWWorld::CustomData> clone() const override;
-
         DoorCustomData& asDoorCustomData() override
         {
             return *this;
@@ -48,11 +46,6 @@ namespace MWClass
         }
     };
 
-    std::unique_ptr<MWWorld::CustomData> DoorCustomData::clone() const
-    {
-        return std::make_unique<DoorCustomData>(*this);
-    }
-
     void Door::insertObjectRendering (const MWWorld::Ptr& ptr, const std::string& model, MWRender::RenderingInterface& renderingInterface) const
     {
         if (!model.empty())

apps/openmw/mwclass/npc.cpp

@@ -246,15 +246,13 @@ namespace
 namespace MWClass
 {
 
-    class NpcCustomData : public MWWorld::CustomData
+    class NpcCustomData : public MWWorld::TypedCustomData<NpcCustomData>
     {
     public:
         MWMechanics::NpcStats mNpcStats;
         MWMechanics::Movement mMovement;
         MWWorld::InventoryStore mInventoryStore;
 
-        std::unique_ptr<MWWorld::CustomData> clone() const override;
-
         NpcCustomData& asNpcCustomData() override
         {
             return *this;
@@ -265,11 +263,6 @@ namespace MWClass
         }
     };
 
-    std::unique_ptr<MWWorld::CustomData> NpcCustomData::clone() const
-    {
-        return std::make_unique<NpcCustomData>(*this);
-    }
-
     const Npc::GMST& Npc::getGmst()
     {
         static GMST gmst;

apps/openmw/mwworld/customdata.hpp

@@ -40,6 +40,15 @@ namespace MWWorld
             virtual MWClass::CreatureLevListCustomData& asCreatureLevListCustomData();
             virtual const MWClass::CreatureLevListCustomData& asCreatureLevListCustomData() const;
     };
+
+    template <class T>
+    struct TypedCustomData : CustomData
+    {
+        std::unique_ptr<CustomData> clone() const final
+        {
+            return std::make_unique<T>(*static_cast<const T*>(this));
+        }
+    };
 }
 
 #endif