From bb5213670c41634c666dd705e196832c74b8aa52 Mon Sep 17 00:00:00 2001
From: Frederic Chardon <chardon.frederic@gmail.com>
Date: Mon, 16 Nov 2020 11:09:08 +0100
Subject: [PATCH] Use bigger hammer to set Actor's position after teleporting.
 Otherwise traceDown() would use old collision object transform and gives
 incorrect results, making the Actor "fall" in the new position.

---
 apps/openmw/mwphysics/actor.cpp         | 24 ++++++++++++------------
 apps/openmw/mwphysics/actor.hpp         |  3 ++-
 apps/openmw/mwphysics/mtphysics.cpp     |  2 +-
 apps/openmw/mwphysics/physicssystem.cpp |  4 ++--
 4 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/apps/openmw/mwphysics/actor.cpp b/apps/openmw/mwphysics/actor.cpp
index 0f3d69d21..430bd4dee 100644
--- a/apps/openmw/mwphysics/actor.cpp
+++ b/apps/openmw/mwphysics/actor.cpp
@@ -74,11 +74,8 @@ Actor::Actor(const MWWorld::Ptr& ptr, const Resource::BulletShape* shape, Physic
 
     updateRotation();
     updateScale();
-    updatePosition();
-    setPosition(mWorldPosition, true);
-
+    resetPosition();
     addCollisionMask(getCollisionMask());
-    updateCollisionObjectPosition();
 }
 
 Actor::~Actor()
@@ -160,15 +157,9 @@ osg::Vec3f Actor::getCollisionObjectPosition() const
     return Misc::Convert::toOsg(mLocalTransform.getOrigin());
 }
 
-void Actor::setPosition(const osg::Vec3f& position, bool reset)
+void Actor::setPosition(const osg::Vec3f& position)
 {
-    if (reset)
-    {
-        mPreviousPosition = position;
-        mNextPosition = position;
-    }
-    else
-        mPreviousPosition = mPosition;
+    mPreviousPosition = mPosition;
     mPosition = position;
 }
 
@@ -178,6 +169,15 @@ void Actor::adjustPosition(const osg::Vec3f& offset)
     mPreviousPosition += offset;
 }
 
+void Actor::resetPosition()
+{
+    updatePosition();
+    mPreviousPosition = mWorldPosition;
+    mPosition = mWorldPosition;
+    mNextPosition = mWorldPosition;
+    updateCollisionObjectPosition();
+}
+
 osg::Vec3f Actor::getPosition() const
 {
     return mPosition;
diff --git a/apps/openmw/mwphysics/actor.hpp b/apps/openmw/mwphysics/actor.hpp
index 6b23b31d3..3d6f93ae0 100644
--- a/apps/openmw/mwphysics/actor.hpp
+++ b/apps/openmw/mwphysics/actor.hpp
@@ -91,7 +91,8 @@ namespace MWPhysics
         /**
           * Store the current position into mPreviousPosition, then move to this position.
           */
-        void setPosition(const osg::Vec3f& position, bool reset=false);
+        void setPosition(const osg::Vec3f& position);
+        void resetPosition();
         void adjustPosition(const osg::Vec3f& offset);
 
         osg::Vec3f getPosition() const;
diff --git a/apps/openmw/mwphysics/mtphysics.cpp b/apps/openmw/mwphysics/mtphysics.cpp
index ff676413b..dbb714fac 100644
--- a/apps/openmw/mwphysics/mtphysics.cpp
+++ b/apps/openmw/mwphysics/mtphysics.cpp
@@ -253,7 +253,7 @@ namespace MWPhysics
             for (const auto& m : mActorsFrameData)
             {
                 m.mActorRaw->setStandingOnPtr(nullptr);
-                m.mActorRaw->setPosition(m.mActorRaw->getWorldPosition(), true);
+                m.mActorRaw->resetPosition();
                 mMovementResults[m.mPtr] = m.mActorRaw->getWorldPosition();
             }
             return mMovementResults;
diff --git a/apps/openmw/mwphysics/physicssystem.cpp b/apps/openmw/mwphysics/physicssystem.cpp
index 5de26fdfc..42ead3606 100644
--- a/apps/openmw/mwphysics/physicssystem.cpp
+++ b/apps/openmw/mwphysics/physicssystem.cpp
@@ -433,8 +433,8 @@ namespace MWPhysics
         ActorMap::iterator found = mActors.find(ptr);
         if (found ==  mActors.end())
             return ptr.getRefData().getPosition().asVec3();
-        else
-            return MovementSolver::traceDown(ptr, position, found->second.get(), mCollisionWorld.get(), maxHeight);
+        found->second->resetPosition();
+        return MovementSolver::traceDown(ptr, position, found->second.get(), mCollisionWorld.get(), maxHeight);
     }
 
     void PhysicsSystem::addHeightField (const float* heights, int x, int y, float triSize, float sqrtVerts, float minH, float maxH, const osg::Object* holdObject)