Rework again SetPos command to make more mods work.

Previous version skipped collision the frame immediately after a call to SetPos. It worked for one-off calls (teleports for instance) and continuous call along a pre-defined path (scenic travel). However, in the case of mod which uses SetPos to simulate a player-controlled movement, it is equivalent to using tcl.
Solution:
1/ skip update of mPosition and  mPreviousPosition to avoid janky interpolation
2/ use back plain moveObject() instead of moveObjectBy() since we don't want physics simulation
3/ rework a little bit waterwalking influence on coordinate because of 1/

apps/openmw/mwbase/world.hpp

@@ -289,7 +289,7 @@ namespace MWBase
             virtual MWWorld::Ptr moveObject(const MWWorld::Ptr &ptr, MWWorld::CellStore* newCell, const osg::Vec3f& position, bool movePhysics=true, bool keepActive=false) = 0;
             ///< @return an updated Ptr
 
-            virtual MWWorld::Ptr moveObjectBy(const MWWorld::Ptr &ptr, const osg::Vec3f& vec, bool moveToActive, bool ignoreCollisions) = 0;
+            virtual MWWorld::Ptr moveObjectBy(const MWWorld::Ptr &ptr, const osg::Vec3f& vec) = 0;
             ///< @return an updated Ptr
 
             virtual void scaleObject (const MWWorld::Ptr& ptr, float scale) = 0;

apps/openmw/mwphysics/actor.cpp

@@ -124,7 +124,6 @@ void Actor::updatePosition()
     mSimulationPosition = worldPosition;
     mPositionOffset = osg::Vec3f();
     mStandingOnPtr = nullptr;
-    mSkipCollisions = true;
     mSkipSimulation = true;
 }
 
@@ -163,17 +162,19 @@ bool Actor::setPosition(const osg::Vec3f& position)
 {
     std::scoped_lock lock(mPositionMutex);
     applyOffsetChange();
-    bool hasChanged = mPosition != position || mWorldPositionChanged;
-    mPreviousPosition = mPosition;
-    mPosition = position;
+    bool hasChanged = (mPosition != position && !mSkipSimulation) || mWorldPositionChanged;
+    if (!mSkipSimulation)
+    {
+        mPreviousPosition = mPosition;
+        mPosition = position;
+    }
     return hasChanged;
 }
 
-void Actor::adjustPosition(const osg::Vec3f& offset, bool ignoreCollisions)
+void Actor::adjustPosition(const osg::Vec3f& offset)
 {
     std::scoped_lock lock(mPositionMutex);
     mPositionOffset += offset;
-    mSkipCollisions = mSkipCollisions || ignoreCollisions;
 }
 
 void Actor::applyOffsetChange()
@@ -274,11 +275,6 @@ void Actor::setStandingOnPtr(const MWWorld::Ptr& ptr)
     mStandingOnPtr = ptr;
 }
 
-bool Actor::skipCollisions()
-{
-    return std::exchange(mSkipCollisions, false);
-}
-
 bool Actor::canMoveToWaterSurface(float waterlevel, const btCollisionWorld* world) const
 {
     const float halfZ = getHalfExtents().z();

apps/openmw/mwphysics/actor.hpp

@@ -89,7 +89,7 @@ namespace MWPhysics
         void updatePosition();
 
         // register a position offset that will be applied during simulation.
-        void adjustPosition(const osg::Vec3f& offset, bool ignoreCollisions);
+        void adjustPosition(const osg::Vec3f& offset);
 
         // apply position offset. Can't be called during simulation
         void applyOffsetChange();
@@ -156,8 +156,6 @@ namespace MWPhysics
             mLastStuckPosition = position;
         }
 
-        bool skipCollisions();
-
         bool canMoveToWaterSurface(float waterlevel, const btCollisionWorld* world) const;
 
     private:
@@ -187,7 +185,6 @@ namespace MWPhysics
         osg::Vec3f mScale;
         osg::Vec3f mPositionOffset;
         bool mWorldPositionChanged;
-        bool mSkipCollisions;
         bool mSkipSimulation;
         mutable std::mutex mPositionMutex;
 

apps/openmw/mwphysics/physicssystem.cpp

@@ -941,7 +941,7 @@ namespace MWPhysics
         , mWasOnGround(actor.getOnGround())
         , mIsAquatic(actor.getPtr().getClass().isPureWaterCreature(actor.getPtr()))
         , mWaterCollision(waterCollision)
-        , mSkipCollisionDetection(actor.skipCollisions() || !actor.getCollisionMode())
+        , mSkipCollisionDetection(!actor.getCollisionMode())
     {
     }
 
@@ -951,8 +951,9 @@ namespace MWPhysics
         mPosition = actor.getPosition();
         if (mWaterCollision && mPosition.z() < mWaterlevel && actor.canMoveToWaterSurface(mWaterlevel, world))
         {
-            mPosition.z() = mWaterlevel;
-            MWBase::Environment::get().getWorld()->moveObject(actor.getPtr(), mPosition, false);
+            MWBase::Environment::get().getWorld()->moveObjectBy(actor.getPtr(), osg::Vec3f(0, 0, mWaterlevel - mPosition.z()));
+            actor.applyOffsetChange();
+            mPosition = actor.getPosition();
         }
         mOldHeight = mPosition.z();
         const auto rotation = actor.getPtr().getRefData().getPosition().asRotationVec3();

apps/openmw/mwscript/transformationextensions.cpp

@@ -32,7 +32,7 @@ namespace MWScript
             std::vector<MWWorld::Ptr> actors;
             MWBase::Environment::get().getWorld()->getActorsStandingOn (ptr, actors);
             for (auto& actor : actors)
-                MWBase::Environment::get().getWorld()->moveObjectBy(actor, diff, false, false);
+                MWBase::Environment::get().getWorld()->moveObjectBy(actor, diff);
         }
 
         template<class R>
@@ -312,7 +312,7 @@ namespace MWScript
                     }
 
                     dynamic_cast<MWScript::InterpreterContext&>(runtime.getContext()).updatePtr(ptr,
-                        MWBase::Environment::get().getWorld()->moveObjectBy(ptr, newPos - curPos, true, true));
+                        MWBase::Environment::get().getWorld()->moveObject(ptr, newPos, true, true));
                 }
         };
 
@@ -731,7 +731,7 @@ namespace MWScript
                     // This approach can be used to create elevators.
                     moveStandingActors(ptr, diff);
                     dynamic_cast<MWScript::InterpreterContext&>(runtime.getContext()).updatePtr(ptr,
-                        MWBase::Environment::get().getWorld()->moveObjectBy(ptr, diff, false, true));
+                        MWBase::Environment::get().getWorld()->moveObjectBy(ptr, diff));
                 }
         };
 
@@ -767,7 +767,7 @@ namespace MWScript
                     // This approach can be used to create elevators.
                     moveStandingActors(ptr, diff);
                     dynamic_cast<MWScript::InterpreterContext&>(runtime.getContext()).updatePtr(ptr,
-                        MWBase::Environment::get().getWorld()->moveObjectBy(ptr, diff, false, true));
+                        MWBase::Environment::get().getWorld()->moveObjectBy(ptr, diff));
                 }
         };
 

apps/openmw/mwworld/worldimp.cpp

@@ -1258,14 +1258,14 @@ namespace MWWorld
         return moveObject(ptr, cell, position, movePhysics);
     }
 
-    MWWorld::Ptr World::moveObjectBy(const Ptr& ptr, const osg::Vec3f& vec, bool moveToActive, bool ignoreCollisions)
+    MWWorld::Ptr World::moveObjectBy(const Ptr& ptr, const osg::Vec3f& vec)
     {
         auto* actor = mPhysics->getActor(ptr);
         osg::Vec3f newpos = ptr.getRefData().getPosition().asVec3() + vec;
         if (actor)
-            actor->adjustPosition(vec, ignoreCollisions);
+            actor->adjustPosition(vec);
         if (ptr.getClass().isActor())
-            return moveObject(ptr, newpos, false, moveToActive && ptr != getPlayerPtr());
+            return moveObject(ptr, newpos, false, ptr != getPlayerPtr());
         return moveObject(ptr, newpos);
     }
 

apps/openmw/mwworld/worldimp.hpp

@@ -376,7 +376,7 @@ namespace MWWorld
             MWWorld::Ptr moveObject (const Ptr& ptr, CellStore* newCell, const osg::Vec3f& position, bool movePhysics=true, bool keepActive=false) override;
             ///< @return an updated Ptr
 
-            MWWorld::Ptr moveObjectBy(const Ptr& ptr, const osg::Vec3f& vec, bool moveToActive, bool ignoreCollisions) override;
+            MWWorld::Ptr moveObjectBy(const Ptr& ptr, const osg::Vec3f& vec) override;
             ///< @return an updated Ptr
 
             void scaleObject (const Ptr& ptr, float scale) override;