hds_items.h

很多二维 三维几何计算算法 C++ 类库

    /*{\Mop returns a generic information slot of |\Mvar|.}*/
    const GenPtr& info() const { return _i; }

    fc_iterator fcit() const      { return *_fcit; }
    void set_fcit(fc_iterator it) { _fcit = it; }
    void reset_fcit()             { _fcit = boost::none; }

    bool is_hole_entry() const 
        /*{\Mop returns true iff |\Mvar| is entry point into a hole face
          cycle of |\Mvar.face()|.}*/
        { return !!_fcit; }
};

template <typename Refs, typename Traits>
class Nef_face_2 {
public:
    typedef Refs           HalfedgeDS;
    typedef Nef_face_2     Base;
    typedef CGAL::Tag_true Supports_face_halfedge;
    typedef typename Refs::Vertex_handle         Vertex_handle;
    typedef typename Refs::Vertex_const_handle   Vertex_const_handle;
    typedef typename Refs::Halfedge_handle       Halfedge_handle;
    typedef typename Refs::Halfedge_const_handle Halfedge_const_handle;
    typedef typename Refs::Face_handle           Face_handle;
    typedef typename Refs::Face_const_handle     Face_const_handle;
    typedef typename Refs::Vertex                Vertex;
    typedef typename Refs::Halfedge              Halfedge;
    typedef void*                                GenPtr;

    typedef typename Traits::Mark  Mark;  // mark information

    class Hole_iterator 
    /*{\Mtypemember iterator for face cycles. Fits the concept 
      |Halfedge_handle|.}*/ 
        : public std::list<Halfedge_handle>::iterator 
    {
        typedef typename std::list<Halfedge_handle>::iterator Ibase;
    public:
        Hole_iterator() : Ibase() {}
        Hole_iterator(const Ibase& b) : Ibase(b) {}
        Hole_iterator(const Hole_iterator& i) : Ibase(i) {}  
        operator Halfedge_handle() const { return Ibase::operator*(); }
        Halfedge& operator*() { return *(Ibase::operator*()); }
        Halfedge_handle operator->() { return Ibase::operator*(); }
    };

    class Hole_const_iterator : 
        public std::list<Halfedge_handle>::const_iterator 
    {
        typedef typename std::list<Halfedge_handle>::const_iterator Ibase;
    public:
        Hole_const_iterator() : Ibase() {}
        Hole_const_iterator(const Ibase& b) : Ibase(b) {}
        Hole_const_iterator(const Hole_const_iterator& i) : Ibase(i) {}  
        operator Halfedge_const_handle() const { return Ibase::operator*(); }
        const Halfedge& operator*() { return *(Ibase::operator*()); }
        Halfedge_const_handle operator->() { return Ibase::operator*(); }
    };

    class Isolated_vertex_iterator 
    /*{\Mtypemember iterator for isolated vertices. Fits the concept 
      |Vertex_handle|.}*/ 
        : public std::list<Vertex_handle>::iterator 
    {
        typedef typename std::list<Vertex_handle>::iterator Ibase;
    public:
        Isolated_vertex_iterator() : Ibase() {}
        Isolated_vertex_iterator(const Ibase& b) : Ibase(b) {}
        Isolated_vertex_iterator(const Isolated_vertex_iterator& i) 
            : Ibase(i) {}  
        operator Vertex_handle() const { return Ibase::operator*(); }
        Vertex& operator*() { return *(Ibase::operator*()); }
        Vertex_handle operator->() { return Ibase::operator*(); }
    };

    class Isolated_vertex_const_iterator  
        : public std::list<Vertex_handle>::const_iterator 
    { 
        typedef typename std::list<Vertex_handle>::const_iterator Ibase;
    public:
        Isolated_vertex_const_iterator() : Ibase() {}
        Isolated_vertex_const_iterator(const Ibase& b) : Ibase(b) {}
        Isolated_vertex_const_iterator(
            const Isolated_vertex_const_iterator& i) : Ibase(i) {}  
        operator Vertex_const_handle() const { return Ibase::operator*(); }
        const Vertex& operator*() { return *(Ibase::operator*()); }
        Vertex_const_handle operator->() { return Ibase::operator*(); }
    };

    /*{\Mtext |Hole_const_iterator| and |Isolated_vertex_const_iterator| 
      are the non mutable versions.}*/

private:
    Halfedge_handle            _e;
    std::list<Halfedge_handle> FC;
    std::list<Vertex_handle>   IV;
    Mark                       _m;
    GenPtr                     _i;
public:

    Nef_face_2() : _e(),_m(0),_i((GenPtr)0xABCD) {}
    /*{\Mcreate constructs an uninitialized face with undefined mark,
      empty face cycle list, and empty isolated vertices list.}*/   

    ~Nef_face_2() { FC.clear(); IV.clear(); }

    void store_fc(Halfedge_handle h) 
        /*{\Mop stores halfedge |h| as an entry into a face cycle of |\Mvar|.
          Postcondition: |h->is_hole_entry()|.}*/
        { FC.push_back(h); h->set_fcit(--FC.end());  
        CGAL_assertion(h->is_hole_entry()); }

    void remove_fc(Halfedge_handle h) 
        /*{\Mop removes halfedge |h| as an entry into a face cycle of |\Mvar|.
          \precond |h->is_hole_entry()| and |h|  is stored in the
          face cycle list of |\Mvar|.
          Postcondition: |!h->is_hole_entry()|.}*/
        { CGAL_assertion(h->is_hole_entry());
        FC.erase(h->fcit()); h->reset_fcit(); }

    void store_iv(Vertex_handle v)
        /*{\Mop stores vertex |v| as an isolated vertex of |\Mvar|.}*/
        { IV.push_back(v); v->set_ivit(--IV.end()); }

    void remove_iv(Vertex_handle v)
        /*{\Mop removes vertex |v| as an isolated vertex of |\Mvar|.
          \precond |v->is_isolated()| and |v| is stored in the
          isolated vertices list of |\Mvar|. 
          Postcondition: |!v->is_isolated()|.}*/
        { CGAL_assertion(v->is_isolated()); 
        IV.erase(v->ivit()); v->reset_ivit(); }
      
    /*{\Mtext\setopdims{4cm}{0cm}}*/

    Hole_iterator  fc_begin() { return FC.begin(); }
    /*{\Mop}*/

    Hole_iterator  fc_end()   { return FC.end(); }
    /*{\Mop the iterator range |[fc_begin(),fc_end())| spans the set of 
      interior face cycles.}*/

    Isolated_vertex_iterator  iv_begin() { return IV.begin(); }
    /*{\Mop}*/

    Isolated_vertex_iterator  iv_end()   { return IV.end(); }
    /*{\Mop the iterator range |[iv_begin(),iv_end())| spans the set of 
      isolated vertices.}*/

    void clear_all_entries()
        {
        for (Hole_iterator hit = fc_begin(); hit!=fc_end(); ++hit) 
            hit->reset_fcit();
        for (Isolated_vertex_iterator vit = iv_begin(); vit!=iv_end(); ++vit) 
            vit->reset_ivit();
        FC.clear(); IV.clear(); }

    /*{\Mtext There are the same iterator ranges defined for the const
      iterators |Hole_const_iterator|, |Isolated_vertex_const_iterator|.
      \restoreopdims}*/

    Hole_const_iterator fc_begin() const { return FC.begin(); }
    Hole_const_iterator fc_end() const   { return FC.end(); }
    Isolated_vertex_const_iterator iv_begin() const { return IV.begin(); }
    Isolated_vertex_const_iterator iv_end() const   { return IV.end(); }

    void set_halfedge(Halfedge_handle h)   { _e = h; } 
    /*{\Mop makes |h| the entry edge into the outer face cycle.}*/
    Halfedge_handle       halfedge()       { return _e; }
    /*{\Mop returns a halfedge in the outer face cycle.}*/
    Halfedge_const_handle halfedge() const { return _e; }

    Mark& mark() { return _m; }
    /*{\Mop returns the mark of |\Mvar|.}*/
    const Mark& mark() const { return _m; }

    GenPtr&       info()       { return _i; }
    /*{\Mop returns a generic information slot of |\Mvar|.}*/
    const GenPtr& info() const { return _i; }
};

class HDS_items {
public:
    template < class Refs, class Traits>
    struct Vertex_wrapper {
        typedef Nef_vertex_2< Refs, Traits>    Vertex;
    };
    template < class Refs, class Traits>
    struct Halfedge_wrapper {
        typedef Nef_halfedge_2< Refs, Traits>  Halfedge;
    };
    template < class Refs, class Traits>
    struct Face_wrapper {
        typedef Nef_face_2< Refs, Traits>      Face;
    };
};

} // namespace CGAL

#endif // CGAL_HDS_ITEMS_H