PSubSet(char* namein, Space& s, GeObList& v)
Builds a projective subset of space s, with debug name in buffer namein. The subset creates its own copy of the name. The geometric objects in list v, after mapping into space s if necessary, span the subset.
PSubSet(char* namein, Space& s, GeObList& bp, GeObList& v)
Builds a projective subset of space s, with debug name in buffer namein. The subset creates its own copy of the name. The geometric objects in lists bp and v, after mapping into space s if necessary, span some projective subspace. The objects in bp are base points that span the set of removed points that are extracted from the subset. This constructor is used to build domain subsets for noninvertible projective maps.
PSubSet(SubSet& s)
Used to downcast a general subset to a projective subset. Only succeeds if the general subset is holding a projective subset.