1 /* 2 Copyright 2005-2007 Adobe Systems Incorporated 3 4 Use, modification and distribution are subject to the Boost Software License, 5 Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at 6 http://www.boost.org/LICENSE_1_0.txt). 7 8 See http://opensource.adobe.com/gil for most recent version including documentation. 9 */ 10 11 /*************************************************************************************************/ 12 13 #ifndef GIL_VIRTUAL_LOCATOR_HPP 14 #define GIL_VIRTUAL_LOCATOR_HPP 15 16 //////////////////////////////////////////////////////////////////////////////////////// 17 /// \file 18 /// \brief Locator for virtual image views 19 /// \author Lubomir Bourdev and Hailin Jin \n 20 /// Adobe Systems Incorporated 21 /// \date 2005-2007 \n Last updated on February 12, 2007 22 /// 23 //////////////////////////////////////////////////////////////////////////////////////// 24 25 #include <boost/iterator/iterator_facade.hpp> 26 #include "position_iterator.hpp" 27 28 namespace boost { namespace gil { 29 30 /// \brief A 2D locator over a virtual image. Upon dereferencing, invokes a given function object passing it its coordinates. Models: PixelLocatorConcept, HasDynamicXStepTypeConcept, HasDynamicYStepTypeConcept, HasTransposedTypeConcept 31 /// \ingroup PixelLocatorModel PixelBasedModel 32 /// 33 template <typename Deref, bool IsTransposed> // A function object that given a point returns a reference. Models PixelDereferenceAdaptorConcept 34 class virtual_2d_locator : public pixel_2d_locator_base<virtual_2d_locator<Deref,IsTransposed>, position_iterator<Deref,IsTransposed>, position_iterator<Deref,1-IsTransposed> > { 35 typedef virtual_2d_locator<Deref,IsTransposed> this_t; 36 public: 37 typedef pixel_2d_locator_base<virtual_2d_locator<Deref,IsTransposed>, position_iterator<Deref,IsTransposed>, position_iterator<Deref,1-IsTransposed> > parent_t; 38 typedef virtual_2d_locator<typename Deref::const_t,IsTransposed> const_t; 39 40 typedef Deref deref_fn_t; 41 typedef typename parent_t::point_t point_t; 42 43 typedef typename parent_t::coord_t coord_t; 44 typedef typename parent_t::x_coord_t x_coord_t; 45 typedef typename parent_t::y_coord_t y_coord_t; 46 typedef typename parent_t::x_iterator x_iterator; 47 typedef typename parent_t::y_iterator y_iterator; 48 49 template <typename NewDeref> struct add_deref { 50 typedef virtual_2d_locator<deref_compose<NewDeref,Deref>,IsTransposed > type; makeboost::gil::virtual_2d_locator::add_deref51 static type make(const virtual_2d_locator<Deref,IsTransposed>& loc, const NewDeref& nderef) { 52 return type(loc.pos(), loc.step(), deref_compose<NewDeref,Deref>(nderef,loc.deref_fn())); 53 } 54 }; 55 virtual_2d_locator(const point_t & p=point_t (0,0),const point_t & step=point_t (1,1),const deref_fn_t & d=deref_fn_t ())56 virtual_2d_locator(const point_t& p=point_t(0,0), const point_t& step=point_t(1,1), const deref_fn_t& d=deref_fn_t()) : _p(p,step,d) {} virtual_2d_locator(const virtual_2d_locator<D,TR> & loc,coord_t y_step)57 template <typename D, bool TR> virtual_2d_locator(const virtual_2d_locator<D,TR>& loc, coord_t y_step) 58 : _p(loc.pos(), point_t(loc.step().x,loc.step().y*y_step), loc.deref_fn()) {} virtual_2d_locator(const virtual_2d_locator<D,TR> & loc,coord_t x_step,coord_t y_step,bool transpose=false)59 template <typename D, bool TR> virtual_2d_locator(const virtual_2d_locator<D,TR>& loc, coord_t x_step, coord_t y_step, bool transpose=false) 60 : _p(loc.pos(), transpose ? 61 point_t(loc.step().x*y_step,loc.step().y*x_step) : 62 point_t(loc.step().x*x_step,loc.step().y*y_step), loc.deref_fn()) { assert(transpose==(IsTransposed!=TR));} 63 virtual_2d_locator(const virtual_2d_locator<D,TR> & pl)64 template <typename D, bool TR> virtual_2d_locator(const virtual_2d_locator<D,TR>& pl) : _p(pl._p) {} virtual_2d_locator(const virtual_2d_locator & pl)65 virtual_2d_locator(const virtual_2d_locator& pl) : _p(pl._p) {} 66 operator ==(const this_t & p) const67 bool operator==(const this_t& p) const { return _p==p._p; } 68 x()69 x_iterator& x() { return *gil_reinterpret_cast<x_iterator*>(this); } y()70 y_iterator& y() { return _p; } x() const71 x_iterator const& x() const { return *gil_reinterpret_cast_c<x_iterator const*>(this); } y() const72 y_iterator const& y() const { return _p; } 73 74 // Returns the y distance between two x_iterators given the difference of their x positions y_distance_to(const this_t & it2,x_coord_t xDiff) const75 y_coord_t y_distance_to(const this_t& it2, x_coord_t xDiff) const { return (it2.pos()[1-IsTransposed] - pos()[1-IsTransposed])/step()[1-IsTransposed]; } is_1d_traversable(x_coord_t) const76 bool is_1d_traversable(x_coord_t) const { return false; } // is there no gap at the end of each row? I.e. can we use x_iterator to visit every pixel instead of nested loops? 77 78 // Methods specific for virtual 2D locator pos() const79 const point_t& pos() const { return _p.pos(); } step() const80 const point_t& step() const { return _p.step(); } deref_fn() const81 const deref_fn_t& deref_fn() const { return _p.deref_fn(); } 82 private: 83 template <typename D, bool TR> friend class virtual_2d_locator; 84 y_iterator _p; // contains the current position, the step and the dereference object 85 }; 86 87 ///////////////////////////// 88 // PixelBasedConcept 89 ///////////////////////////// 90 91 template <typename D, bool TR> 92 struct channel_type<virtual_2d_locator<D,TR> > : public channel_type<typename virtual_2d_locator<D,TR>::parent_t> { 93 }; 94 95 template <typename D, bool TR> 96 struct color_space_type<virtual_2d_locator<D,TR> > : public color_space_type<typename virtual_2d_locator<D,TR>::parent_t> { 97 }; 98 99 template <typename D, bool TR> 100 struct channel_mapping_type<virtual_2d_locator<D,TR> > : public channel_mapping_type<typename virtual_2d_locator<D,TR>::parent_t> { 101 }; 102 103 template <typename D, bool TR> 104 struct is_planar<virtual_2d_locator<D,TR> > : public is_planar<typename virtual_2d_locator<D,TR>::parent_t> { 105 }; 106 107 ///////////////////////////// 108 // HasDynamicXStepTypeConcept 109 ///////////////////////////// 110 111 template <typename D, bool TR> 112 struct dynamic_x_step_type<virtual_2d_locator<D,TR> > { 113 typedef virtual_2d_locator<D,TR> type; 114 }; 115 116 ///////////////////////////// 117 // HasDynamicYStepTypeConcept 118 ///////////////////////////// 119 120 template <typename D, bool TR> 121 struct dynamic_y_step_type<virtual_2d_locator<D,TR> > { 122 typedef virtual_2d_locator<D,TR> type; 123 }; 124 125 ///////////////////////////// 126 // HasTransposedTypeConcept 127 ///////////////////////////// 128 129 template <typename D, bool IsTransposed> 130 struct transposed_type<virtual_2d_locator<D,IsTransposed> > { 131 typedef virtual_2d_locator<D,1-IsTransposed> type; 132 }; 133 134 } } // namespace boost::gil 135 136 #endif 137