Problems of limit mesh approx. Approximation error How to estimate the error(distance) between a Loop surface and its limit mesh? Subdivision depth estimation How many steps of subdivision would be necessary to satisfy a user-specified error tolerance?Problems of limit mesh approx. ‡ Approximation error „ How to estimate the error (distance) between a Loop surface and its limit mesh? ‡ Subdivision depth estimation „ How many steps of subdivision would be necessary to satisfy a user-specified error tolerance?