Arrangement-Traits Classes

It is time for you to make an acquaintance with the arrangement traits classes, mentioned a number of times in the previous chapters. A traits class encapsulates the definitions of the geometric entities and the implementation of the geometric predicates and constructions that handle these geometric entities, used by the Arrangement_2 class and by its peripheral modules. The identified minimal requirements imposed by the various algorithms that apply to arrangements are organized in a hierarchy of refined geometry-traits concepts.