Core/Units: Properly update passenger position if vehicle uses waypoint movement. Fixes e.g. Icefang path

src/server/game/Entities/Unit/Unit.cpp

@@ -17171,14 +17171,18 @@ bool Unit::UpdatePosition(float x, float y, float z, float orientation, bool tel
             GetMap()->CreatureRelocation(ToCreature(), x, y, z, orientation);
     }
     else if (turn)
-        SetOrientation(orientation);
-
-    if ((relocated || turn) && IsVehicle())
-        GetVehicleKit()->RelocatePassengers(x, y, z, orientation);
+        UpdateOrientation(orientation);
 
     return (relocated || turn);
 }
 
+void Unit::UpdateOrientation(float orientation)
+{
+    SetOrientation(orientation);
+    if (IsVehicle())
+        GetVehicleKit()->RelocatePassengers(GetPositionX(), GetPositionY(), GetPositionZ(), GetOrientation());
+}
+
 void Unit::SendThreatListUpdate()
 {
     if (!getThreatManager().isThreatListEmpty())

src/server/game/Entities/Unit/Unit.h

@@ -1614,6 +1614,7 @@ class Unit : public WorldObject
         virtual bool UpdatePosition(float x, float y, float z, float ang, bool teleport = false);
         // returns true if unit's position really changed
         bool UpdatePosition(const Position &pos, bool teleport = false) { return UpdatePosition(pos.GetPositionX(), pos.GetPositionY(), pos.GetPositionZ(), pos.GetOrientation(), teleport); }
+        void UpdateOrientation(float orientation);
 
         void KnockbackFrom(float x, float y, float speedXY, float speedZ);
         void JumpTo(float speedXY, float speedZ, bool forward = true);

src/server/game/Entities/Vehicle/Vehicle.cpp

@@ -431,6 +431,7 @@ void Vehicle::RemovePassenger(Unit* unit)
         sScriptMgr->OnRemovePassenger(this, unit);
 }
 
+//! Must be called after m_base::Relocate
 void Vehicle::RelocatePassengers(float x, float y, float z, float ang)
 {
     ASSERT(_me->GetMap());
@@ -440,8 +441,6 @@ void Vehicle::RelocatePassengers(float x, float y, float z, float ang)
         if (Unit* passenger = ObjectAccessor::GetUnit(*GetBase(), itr->second.Passenger))
         {
             ASSERT(passenger->IsInWorld());
-            ASSERT(passenger->IsOnVehicle(GetBase()));
-            ASSERT(GetSeatForPassenger(passenger));
 
             float px = x + passenger->m_movementInfo.t_pos.m_positionX;
             float py = y + passenger->m_movementInfo.t_pos.m_positionY;

src/server/game/Maps/Map.cpp

@@ -32,6 +32,7 @@
 #include "Group.h"
 #include "LFGMgr.h"
 #include "DynamicTree.h"
+#include "Vehicle.h"
 
 union u_map_magic
 {
@@ -702,6 +703,8 @@ void Map::PlayerRelocation(Player* player, float x, float y, float z, float orie
     Cell new_cell(x, y);
 
     player->Relocate(x, y, z, orientation);
+    if (player->IsVehicle())
+        player->GetVehicleKit()->RelocatePassengers(x, y, z, orientation);
 
     if (old_cell.DiffGrid(new_cell) || old_cell.DiffCell(new_cell))
     {
@@ -740,6 +743,8 @@ void Map::CreatureRelocation(Creature* creature, float x, float y, float z, floa
     else
     {
         creature->Relocate(x, y, z, ang);
+        if (creature->IsVehicle())
+            creature->GetVehicleKit()->RelocatePassengers(x, y, z, ang);
         creature->UpdateObjectVisibility(false);
         RemoveCreatureFromMoveList(creature);
     }