Core/Movement: Prevent dynamic changes of movement flags for charmed creatures

Closes #10075
Closes #10079

src/server/game/Entities/Creature/Creature.cpp

@@ -2586,12 +2586,16 @@ Unit* Creature::SelectNearestHostileUnitInAggroRange(bool useLOS) const
 
 void Creature::UpdateMovementFlags()
 {
+    // Do not update movement flags if creature is controlled by a player (charm/vehicle)
+    if (m_movedPlayer)
+        return;
+
     // Set the movement flags if the creature is in that mode. (Only fly if actually in air, only swim if in water, etc)
     float ground = GetMap()->GetHeight(GetPositionX(), GetPositionY(), GetPositionZMinusOffset());
 
-    bool isInAir = !IsFalling() && (G3D::fuzzyGt(GetPositionZMinusOffset(), ground + 0.05f) || G3D::fuzzyLt(GetPositionZMinusOffset(), ground - 0.05f)); // Can be underground too, prevent the falling
+    bool isInAir = (G3D::fuzzyGt(GetPositionZMinusOffset(), ground + 0.05f) || G3D::fuzzyLt(GetPositionZMinusOffset(), ground - 0.05f)); // Can be underground too, prevent the falling
 
-    if (GetCreatureTemplate()->InhabitType & INHABIT_AIR && isInAir)
+    if (GetCreatureTemplate()->InhabitType & INHABIT_AIR && isInAir && !IsFalling())
     {
         if (GetCreatureTemplate()->InhabitType & INHABIT_GROUND)
             SetCanFly(true);
@@ -2604,6 +2608,9 @@ void Creature::UpdateMovementFlags()
         SetDisableGravity(false);
     }
 
+    if (!isInAir)
+        RemoveUnitMovementFlag(MOVEMENTFLAG_FALLING);
+
     SetSwim(GetCreatureTemplate()->InhabitType & INHABIT_WATER && IsInWater());
 }
 

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

@@ -17406,9 +17406,19 @@ bool Unit::SetDisableGravity(bool disable, bool /*packetOnly = false*/)
         return false;
 
     if (disable)
+    {
         AddUnitMovementFlag(MOVEMENTFLAG_DISABLE_GRAVITY);
+        RemoveUnitMovementFlag(MOVEMENTFLAG_FALLING);
+    }
     else
+    {
         RemoveUnitMovementFlag(MOVEMENTFLAG_DISABLE_GRAVITY);
+        if (!HasUnitMovementFlag(MOVEMENTFLAG_CAN_FLY))
+        {
+            m_movementInfo.SetFallTime(0);
+            AddUnitMovementFlag(MOVEMENTFLAG_FALLING);
+        }
+    }
 
     return true;
 }
@@ -17432,9 +17442,19 @@ bool Unit::SetCanFly(bool enable)
         return false;
 
     if (enable)
+    {
         AddUnitMovementFlag(MOVEMENTFLAG_CAN_FLY);
+        RemoveUnitMovementFlag(MOVEMENTFLAG_FALLING);
+    }
     else
-        RemoveUnitMovementFlag(MOVEMENTFLAG_CAN_FLY);
+    {
+        RemoveUnitMovementFlag(MOVEMENTFLAG_CAN_FLY | MOVEMENTFLAG_MASK_MOVING_FLY);
+        if (!IsLevitating())
+        {
+            m_movementInfo.SetFallTime(0);
+            AddUnitMovementFlag(MOVEMENTFLAG_FALLING);
+        }
+    }
 
     return true;
 }

src/server/game/Server/WorldSession.cpp

@@ -869,6 +869,10 @@ void WorldSession::ReadMovementInfo(WorldPacket &data, MovementInfo* mi)
         !GetPlayer()->m_mover->HasAuraType(SPELL_AURA_MOD_INCREASE_MOUNTED_FLIGHT_SPEED),
         MOVEMENTFLAG_FLYING | MOVEMENTFLAG_CAN_FLY);
 
+    //! Cannot fly and fall at the same time
+    REMOVE_VIOLATING_FLAGS(mi->HasMovementFlag(MOVEMENTFLAG_CAN_FLY | MOVEMENTFLAG_DISABLE_GRAVITY) && mi->HasMovementFlag(MOVEMENTFLAG_FALLING),
+        MOVEMENTFLAG_FALLING);
+
     #undef REMOVE_VIOLATING_FLAGS
 }
 

src/server/game/Spells/Auras/SpellAuraEffects.cpp

@@ -2558,17 +2558,9 @@ void AuraEffect::HandleAuraAllowFlight(AuraApplication const* aurApp, uint8 mode
             return;
     }
 
-    //! Not entirely sure if this should be sent for creatures as well, but I don't think so.
-    if (!apply)
-    {
-        target->m_movementInfo.SetFallTime(0);
-        target->RemoveUnitMovementFlag(MOVEMENTFLAG_MASK_MOVING_FLY);
-        target->AddUnitMovementFlag(MOVEMENTFLAG_FALLING);
-    }
-
     target->SetCanFly(apply);
 
-    if (target->GetTypeId() == TYPEID_UNIT)
+    if (!apply && target->GetTypeId() == TYPEID_UNIT && !target->IsLevitating())
         target->GetMotionMaster()->MoveFall();
 }
 
@@ -2955,16 +2947,9 @@ void AuraEffect::HandleAuraModIncreaseFlightSpeed(AuraApplication const* aurApp,
         // do not remove unit flag if there are more than this auraEffect of that kind on unit on unit
         if (mode & AURA_EFFECT_HANDLE_SEND_FOR_CLIENT_MASK && (apply || (!target->HasAuraType(SPELL_AURA_MOD_INCREASE_MOUNTED_FLIGHT_SPEED) && !target->HasAuraType(SPELL_AURA_FLY))))
         {
-            if (!apply)
-            {
-                target->m_movementInfo.SetFallTime(0);
-                target->RemoveUnitMovementFlag(MOVEMENTFLAG_MASK_MOVING_FLY);
-                target->AddUnitMovementFlag(MOVEMENTFLAG_FALLING);
-            }
-
             target->SetCanFly(apply);
 
-            if (target->GetTypeId() == TYPEID_UNIT)
+            if (!apply && target->GetTypeId() == TYPEID_UNIT && !target->IsLevitating())
                 target->GetMotionMaster()->MoveFall();
         }