halfmesh_vertex.h

// Description: Half-edge structure vertex

#ifndef PASTELGEOMETRY_HALFMESH_VERTEX_H
#define PASTELGEOMETRY_HALFMESH_VERTEX_H

#include "pastel/geometry/halfmesh/halfmesh_fwd.h"

namespace Pastel
{

    namespace HalfMesh_
    {

        template <typename Settings>
        class Vertex
            : boost::less_than_comparable<Vertex<Settings>
            , boost::equality_comparable<Vertex<Settings>
            > >
            , public HalfMesh_Fwd<Settings>::VertexData_Class
        {
        public:
            using Fwd = HalfMesh_Fwd<Settings>;
            PASTEL_FWD(VertexData_Class);
            PASTEL_FWD(Half_Iterator);
            PASTEL_FWD(Half_ConstIterator);

            operator VertexData_Class&()
            {
                return data();
            }

            operator const VertexData_Class&() const
            {
                return data();
            }

            VertexData_Class& data()
            {
                return *this;
            }

            const VertexData_Class& data() const
            {
                return *this;
            }

            Half_Iterator half()
            {
                return half_;
            }

            Half_ConstIterator half() const
            {
                return removeConst(*this).half();
            }

            bool free() const
            {
                return isolated() || !findFree().empty();
            }

            Half_ConstIterator findFree() const
            {
                if (isolated())
                {
                    return Half_ConstIterator();
                }

                Half_ConstIterator begin = half();
                Half_ConstIterator current = begin;
                do
                {
                    if (current->left().empty())
                    {
                        return current;
                    }
                    current = current->rotateNext();
                }
                while (current != begin);

                return Half_ConstIterator();
            }

            bool isolated() const
            {
                return half().empty();
            }

        protected:
            // These functions are protected, rather than
            // private, so that Vertex can be used as a base
            // class. In particular, this is needed for the 
            // Inherited_Class used in List.

            template <typename... Type>
            Vertex(Type&&... data)
            : VertexData_Class(std::forward<Type>(data)...)
            {
            }

            Vertex(const Vertex& that)
            : VertexData_Class(that) 
            {
            }

            Vertex(Vertex&& that)
            : VertexData_Class(std::move(that))
            {
            }

        private:
            template <typename, template <typename> class>
            friend class Pastel::HalfMesh;

            Half_Iterator half_;
        };

    }

}

#endif