31struct position_iterator :
public iterator_facade<position_iterator<Deref,Dim>,
32 typename Deref::value_type,
33 std::random_access_iterator_tag,
34 typename Deref::reference,
35 typename Deref::argument_type::template axis<Dim>::coord_t> {
36 using parent_t = iterator_facade<position_iterator<Deref,Dim>,
37 typename Deref::value_type,
38 std::random_access_iterator_tag,
39 typename Deref::reference,
40 typename Deref::argument_type::template axis<Dim>::coord_t>;
41 using difference_type =
typename parent_t::difference_type;
42 using reference =
typename parent_t::reference;
43 using point_t =
typename Deref::argument_type;
45 position_iterator() {}
46 position_iterator(point_t
const& p, point_t
const& step, Deref
const& d) : _p(p), _step(step), _d(d) {}
48 position_iterator(position_iterator
const& p) : _p(p._p), _step(p._step), _d(p._d) {}
51 position_iterator(position_iterator<D,Dim>
const& p) : _p(p._p), _step(p._step), _d(p._d) {}
53 auto operator=(position_iterator
const& p) -> position_iterator&
61 auto pos()
const -> point_t
const& {
return _p; }
62 auto step()
const -> point_t
const& {
return _step; }
63 auto deref_fn()
const -> Deref
const& {
return _d; }
65 void set_step(difference_type s) { _step[Dim]=s; }
80 friend class boost::iterator_core_access;
81 reference dereference()
const {
return _d(_p); }
82 void increment() { _p[Dim]+=_step[Dim]; }
83 void decrement() { _p[Dim]-=_step[Dim]; }
84 void advance(difference_type d) { _p[Dim]+=d*_step[Dim]; }
86 difference_type distance_to(
const position_iterator& it)
const {
return (it._p[Dim]-_p[Dim])/_step[Dim]; }
87 bool equal(
const position_iterator& it)
const {
return _p==it._p; }