Core/Movement: Fixed vehicle passengers disappearing clientside

Closes #11411

2 files changed, 39 insertions, 17 deletions

diff --git a/src/server/game/Entities/Unit/Unit.cpp b/src/server/game/Entities/Unit/Unit.cpp
index cb390cc4654..099adb0b659 100644
--- a/src/server/game/Entities/Unit/Unit.cpp
+++ b/src/server/game/Entities/Unit/Unit.cpp
@@ -405,7 +405,7 @@ void Unit::UpdateSplinePosition()
     m_movesplineTimer.Reset(positionUpdateDelay);
     Movement::Location loc = movespline->ComputePosition();
 
-    if (HasUnitMovementFlag(MOVEMENTFLAG_ONTRANSPORT))
+    if (movespline->onTransport)
     {
         Position& pos = m_movementInfo.transport.pos;
         pos.m_positionX = loc.x;
@@ -15524,7 +15524,7 @@ void Unit::SetStunned(bool apply)
 
         // Creature specific
         if (GetTypeId() != TYPEID_PLAYER)
-            ToCreature()->StopMoving();
+            StopMoving();
         else
             SetStandState(UNIT_STAND_STATE_STAND);
 
@@ -15582,7 +15582,7 @@ void Unit::SetRooted(bool apply)
             WorldPacket data(SMSG_SPLINE_MOVE_ROOT, 8);
             data.append(GetPackGUID());
             SendMessageToSet(&data, true);
-            ToCreature()->StopMoving();
+            StopMoving();
         }
     }
     else
diff --git a/src/server/game/Movement/Spline/MoveSplineInit.cpp b/src/server/game/Movement/Spline/MoveSplineInit.cpp
index f6ef219522c..87d8e4a0c34 100644
--- a/src/server/game/Movement/Spline/MoveSplineInit.cpp
+++ b/src/server/game/Movement/Spline/MoveSplineInit.cpp
@@ -60,23 +60,27 @@ namespace Movement
     {
         MoveSpline& move_spline = *unit->movespline;
 
-        bool transport = false;
-        Location real_position(unit->GetPositionX(), unit->GetPositionY(), unit->GetPositionZMinusOffset(), unit->GetOrientation());
-        // Elevators also use MOVEMENTFLAG_ONTRANSPORT but we do not keep track of their position changes
-        if (unit->HasUnitMovementFlag(MOVEMENTFLAG_ONTRANSPORT) && unit->GetTransGUID())
-        {
-            transport = true;
-            real_position.x = unit->GetTransOffsetX();
-            real_position.y = unit->GetTransOffsetY();
-            real_position.z = unit->GetTransOffsetZ();
-            real_position.orientation = unit->GetTransOffsetO();
-        }
-
+        // Elevators also use MOVEMENTFLAG_ONTRANSPORT but we do not keep track of their position changes (movementInfo.transport.guid is 0 in that case)
+        bool transport = unit->HasUnitMovementFlag(MOVEMENTFLAG_ONTRANSPORT) && unit->GetTransGUID();
+        Location real_position;
         // there is a big chance that current position is unknown if current state is not finalized, need compute it
         // this also allows CalculatePath spline position and update map position in much greater intervals
         // Don't compute for transport movement if the unit is in a motion between two transports
         if (!move_spline.Finalized() && move_spline.onTransport == transport)
             real_position = move_spline.ComputePosition();
+        else
+        {
+            Position const* pos;
+            if (!transport)
+                pos = unit;
+            else
+                pos = &unit->m_movementInfo.transport.pos;
+
+            real_position.x = pos->GetPositionX();
+            real_position.y = pos->GetPositionY();
+            real_position.z = pos->GetPositionZ();
+            real_position.orientation = unit->GetOrientation();
+        }
 
         // should i do the things that user should do? - no.
         if (args.path.empty())
@@ -135,14 +139,32 @@ namespace Movement
         if (move_spline.Finalized())
             return;
 
-        Location loc = move_spline.ComputePosition();
+        bool transport = unit->HasUnitMovementFlag(MOVEMENTFLAG_ONTRANSPORT) && unit->GetTransGUID();
+        Location loc;
+        if (move_spline.onTransport == transport)
+            loc = move_spline.ComputePosition();
+        else
+        {
+            Position const* pos;
+            if (!transport)
+                pos = unit;
+            else
+                pos = &unit->m_movementInfo.transport.pos;
+
+            loc.x = pos->GetPositionX();
+            loc.y = pos->GetPositionY();
+            loc.z = pos->GetPositionZ();
+            loc.orientation = unit->GetOrientation();
+        }
+
         args.flags = MoveSplineFlag::Done;
         unit->m_movementInfo.RemoveMovementFlag(MOVEMENTFLAG_FORWARD | MOVEMENTFLAG_SPLINE_ENABLED);
+        move_spline.onTransport = transport;
         move_spline.Initialize(args);
 
         WorldPacket data(SMSG_MONSTER_MOVE, 64);
         data.append(unit->GetPackGUID());
-        if (unit->HasUnitMovementFlag(MOVEMENTFLAG_ONTRANSPORT) && unit->GetTransGUID())
+        if (transport)
         {
             data.SetOpcode(SMSG_MONSTER_MOVE_TRANSPORT);
             data.appendPackGUID(unit->GetTransGUID());