friend inline bool same_position( const limited& a, const limited& b ) { return same_position(a.range, b.range); }
friend inline bool same_position( const transformed& a, const transformed& b ) { return same_position(a.range, b.range); }
bool test(entity const & e) const { return same_position(e, m_ent) && e.id() == ID; }
bool test(entity const & e) const { return same_position(e, *m_eptr); }