Core/PacketIO: Fixed object update failures

Closes #8105

src/server/game/Entities/Object/Object.cpp

@@ -397,8 +397,7 @@ void Object::BuildMovementUpdate(ByteBuffer* data, uint16 flags) const
             hasTransportTime2 = self->HasExtraUnitMovementFlag(MOVEMENTFLAG2_INTERPOLATED_MOVEMENT);
             hasPitch = ((movementFlags & (MOVEMENTFLAG_SWIMMING | MOVEMENTFLAG_FLYING)) ||
                 (movementFlagsExtra & MOVEMENTFLAG2_ALWAYS_ALLOW_PITCHING));
-            hasFallDirection = movementFlags & MOVEMENTFLAG_FALLING;
-            hasFallData = hasFallDirection; // FallDirection implies that FallData is set as well
+            hasFallData = hasFallDirection = movementFlags & MOVEMENTFLAG_FALLING;
             hasSplineElevation = movementFlags & MOVEMENTFLAG_SPLINE_ELEVATION;
 
             movementFlags &= MOVEMENTFLAG_MASK_CREATURE_ALLOWED;
@@ -412,9 +411,9 @@ void Object::BuildMovementUpdate(ByteBuffer* data, uint16 flags) const
         if (movementFlags)
             data->WriteBits(movementFlags, 30);
 
-        data->WriteBit(0);
+        data->WriteBit(hasSpline && GetTypeId() == TYPEID_PLAYER);              // Has spline (from MovementInfo)
         data->WriteBit(!hasPitch);                                              // Has pitch
-        data->WriteBit(hasSpline);                                              // Has spline data
+        data->WriteBit(hasSpline);                                              // Has spline data (independent)
         data->WriteBit(hasFallData);                                            // Has fall data
         data->WriteBit(!hasSplineElevation);                                    // Has spline elevation
         data->WriteBit(guid[5]);