Don't cache Ptr, it can be updated while the simulation is running.

apps/openmw/mwphysics/movementsolver.cpp

@@ -78,12 +78,14 @@ namespace MWPhysics
                                            WorldFrameData& worldData)
     {
         auto* physicActor = actor.mActorRaw;
-        auto ptr = actor.mPtr;
         const ESM::Position& refpos = actor.mRefpos;
         // Early-out for totally static creatures
         // (Not sure if gravity should still apply?)
-        if (!ptr.getClass().isMobile(ptr))
-            return;
+        {
+            const auto ptr = physicActor->getPtr();
+            if (!ptr.getClass().isMobile(ptr))
+                return;
+        }
 
         // Reset per-frame data
         physicActor->setWalkingOnWater(false);
@@ -211,6 +213,7 @@ namespace MWPhysics
             if (result)
             {
                 // don't let pure water creatures move out of water after stepMove
+                const auto ptr = physicActor->getPtr();
                 if (ptr.getClass().isPureWaterCreature(ptr) && newPosition.z() + halfExtents.z() > actor.mWaterlevel)
                     newPosition = oldPosition;
             }

apps/openmw/mwphysics/mtphysics.cpp

@@ -87,12 +87,13 @@ namespace
 
     void updateMechanics(MWPhysics::ActorFrameData& actorData)
     {
+        auto ptr = actorData.mActorRaw->getPtr();
         if (actorData.mDidJump)
-            handleJump(actorData.mPtr);
+            handleJump(ptr);
 
-        MWMechanics::CreatureStats& stats = actorData.mPtr.getClass().getCreatureStats(actorData.mPtr);
+        MWMechanics::CreatureStats& stats = ptr.getClass().getCreatureStats(ptr);
         if (actorData.mNeedLand)
-            stats.land(actorData.mPtr == MWMechanics::getPlayer() && (actorData.mFlying || actorData.mSwimming));
+            stats.land(ptr == MWMechanics::getPlayer() && (actorData.mFlying || actorData.mSwimming));
         else if (actorData.mFallHeight < 0)
             stats.addToFallHeight(-actorData.mFallHeight);
     }
@@ -218,8 +219,13 @@ namespace MWPhysics
         {
             for (auto& data : mActorsFrameData)
             {
+                const auto actorActive = [&data](const auto& newFrameData) -> bool
+                {
+                    const auto actor = data.mActor.lock();
+                    return actor && actor->getPtr() == newFrameData.mActorRaw->getPtr();
+                };
                 // Only return actors that are still part of the scene
-                if (std::any_of(actorsData.begin(), actorsData.end(), [&data](const auto& newFrameData) { return data.mActorRaw->getPtr() == newFrameData.mActorRaw->getPtr(); }))
+                if (std::any_of(actorsData.begin(), actorsData.end(), actorActive))
                 {
                     updateMechanics(data);
 

apps/openmw/mwphysics/physicssystem.cpp

@@ -783,7 +783,7 @@ namespace MWPhysics
             if (numSteps == 0)
                 standingOn = physicActor->getStandingOnPtr();
 
-            actorsFrameData.emplace_back(std::move(physicActor), character, standingOn, moveToWaterSurface, movement, slowFall, waterlevel);
+            actorsFrameData.emplace_back(std::move(physicActor), standingOn, moveToWaterSurface, movement, slowFall, waterlevel);
         }
         mMovementQueue.clear();
         return actorsFrameData;
@@ -925,18 +925,18 @@ namespace MWPhysics
             mDebugDrawer->addCollision(position, normal);
     }
 
-    ActorFrameData::ActorFrameData(const std::shared_ptr<Actor>& actor, const MWWorld::Ptr character, const MWWorld::Ptr standingOn,
+    ActorFrameData::ActorFrameData(const std::shared_ptr<Actor>& actor, const MWWorld::Ptr standingOn,
             bool moveToWaterSurface, osg::Vec3f movement, float slowFall, float waterlevel)
         : mActor(actor), mActorRaw(actor.get()), mStandingOn(standingOn),
         mDidJump(false), mNeedLand(false), mMoveToWaterSurface(moveToWaterSurface),
         mWaterlevel(waterlevel), mSlowFall(slowFall), mOldHeight(0), mFallHeight(0), mMovement(movement), mPosition(), mRefpos()
     {
         const MWBase::World *world = MWBase::Environment::get().getWorld();
-        mPtr = actor->getPtr();
-        mFlying = world->isFlying(character);
-        mSwimming = world->isSwimming(character);
-        mWantJump = mPtr.getClass().getMovementSettings(mPtr).mPosition[2] != 0;
-        mIsDead = mPtr.getClass().getCreatureStats(mPtr).isDead();
+        const auto ptr = actor->getPtr();
+        mFlying = world->isFlying(ptr);
+        mSwimming = world->isSwimming(ptr);
+        mWantJump = ptr.getClass().getMovementSettings(ptr).mPosition[2] != 0;
+        mIsDead = ptr.getClass().getCreatureStats(ptr).isDead();
         mWasOnGround = actor->getOnGround();
     }
 
@@ -950,7 +950,7 @@ namespace MWPhysics
             mActorRaw->setPosition(mPosition);
         }
         mOldHeight = mPosition.z();
-        mRefpos = mPtr.getRefData().getPosition();
+        mRefpos = mActorRaw->getPtr().getRefData().getPosition();
     }
 
     WorldFrameData::WorldFrameData()

apps/openmw/mwphysics/physicssystem.hpp

@@ -78,11 +78,10 @@ namespace MWPhysics
 
     struct ActorFrameData
     {
-        ActorFrameData(const std::shared_ptr<Actor>& actor, const MWWorld::Ptr character, const MWWorld::Ptr standingOn, bool moveToWaterSurface, osg::Vec3f movement, float slowFall, float waterlevel);
+        ActorFrameData(const std::shared_ptr<Actor>& actor, const MWWorld::Ptr standingOn, bool moveToWaterSurface, osg::Vec3f movement, float slowFall, float waterlevel);
         void  updatePosition();
         std::weak_ptr<Actor> mActor;
         Actor* mActorRaw;
-        MWWorld::Ptr mPtr;
         MWWorld::Ptr mStandingOn;
         bool mFlying;
         bool mSwimming;

apps/openmw/mwphysics/ptrholder.hpp

@@ -1,6 +1,8 @@
 #ifndef OPENMW_MWPHYSICS_PTRHOLDER_H
 #define OPENMW_MWPHYSICS_PTRHOLDER_H
 
+#include <mutex>
+
 #include "../mwworld/ptr.hpp"
 
 namespace MWPhysics
@@ -12,21 +14,27 @@ namespace MWPhysics
 
         void updatePtr(const MWWorld::Ptr& updated)
         {
+            std::scoped_lock lock(mMutex);
             mPtr = updated;
         }
 
         MWWorld::Ptr getPtr()
         {
+            std::scoped_lock lock(mMutex);
             return mPtr;
         }
 
         MWWorld::ConstPtr getPtr() const
         {
+            std::scoped_lock lock(mMutex);
             return mPtr;
         }
 
     protected:
         MWWorld::Ptr mPtr;
+
+    private:
+        mutable std::mutex mMutex;
     };
 }