const ObjectType3D &get_3d(const ObjectType &) const;
template<typename T>
const typename TypeMap3D<T>::Type3D &get_3d(const T &ot) const
{ return dynamic_cast<const typename TypeMap3D<T>::Type3D &>(get_3d(static_cast<const ObjectType &>(ot))); }
const ObjectType3D &get_3d(const ObjectType &) const;
template<typename T>
const typename TypeMap3D<T>::Type3D &get_3d(const T &ot) const
{ return dynamic_cast<const typename TypeMap3D<T>::Type3D &>(get_3d(static_cast<const ObjectType &>(ot))); }