/// <summary>
        /// Serializes physics and takes into account support (what's entity standing on)
        /// </summary>
        private void SerializePhysicsWithSupport(BitStream stream, EndpointId forClient,uint timestamp, byte packetId, int maxBitPosition)
        {
            if (stream.Writing)
            {
                // TODO: only prototype implementation
                SetSupport(FindSupportDelegate());

                stream.WriteBool(m_supportPhysics != null);
                if (m_supportPhysics != null)
                {
                    stream.WriteInt64(m_supportPhysics.Entity.EntityId);
                    var localToParent = Entity.WorldMatrix * MatrixD.Invert(m_supportPhysics.Entity.PositionComp.WorldMatrix);
                    stream.Write(localToParent.Translation);
                    stream.Write(Quaternion.CreateFromForwardUp(localToParent.Forward, localToParent.Up).ToVector4());
                    bool moving = IsMoving(Entity);
                    stream.WriteBool(moving);

                    SerializeVelocities(stream, Entity, EffectiveSimulationRatio, !IsControlledLocally, moving);
                }
                else
                {
                    base.Serialize(stream, forClient,timestamp, packetId, maxBitPosition);
                }
            }
            else
            {
                if (stream.ReadBool())
                {
                    MyEntity support;
                    bool apply = MyEntities.TryGetEntityById(stream.ReadInt64(), out support) && !IsControlledLocally;

                    var pos = stream.ReadVector3D();
                    var orient = Quaternion.FromVector4(stream.ReadVector4());

                    if (apply)
                    {
                        var old = Entity.PositionComp.WorldMatrix;

                        MatrixD localToParent = MatrixD.CreateFromQuaternion(orient);
                        localToParent.Translation = pos;
                        MatrixD matrix = localToParent * support.WorldMatrix;
                        Entity.PositionComp.SetWorldMatrix(matrix, null, true);

                        SetSupport(MySupportHelper.FindPhysics(support));

                        var handler = MoveHandler;
                        if (handler != null)
                        {
                            handler(ref old, ref matrix);
                        }
                    }
                    else
                    {
                        SetSupport(null);
                    }
                    bool moving = stream.ReadBool();
                    SerializeVelocities(stream, Entity, EffectiveSimulationRatio, apply, moving);

                }
                else
                {
                    SetSupport(null);
                    base.Serialize(stream, forClient, timestamp, packetId, maxBitPosition);
                }
            }
        }