This paper describes a method that uses a hybird implicit/explicit method.
It uses explicit integration on the elastic forces and implicit integration
on the damping forces. By doing so, it tries to improve the other cloth
methods that tend to smooth the cloth.
By using explicit update for positions, it allows to enforce variety of
constraints. For the forces between trianges, it uses the same method as
in Baraff and Witkin. It also allows to model particular consistent folds
with non-zero rest angles. In collision, it describes a method that
maintains folds while penetrating objects instead of flattening out.