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00013 #ifndef GIL_BIT_ALIGNED_PIXEL_REFERENCE_HPP
00014 #define GIL_BIT_ALIGNED_PIXEL_REFERENCE_HPP
00015
00024
00025 #include <functional>
00026 #include <boost/mpl/accumulate.hpp>
00027 #include <boost/mpl/at.hpp>
00028 #include <boost/mpl/bool.hpp>
00029 #include <boost/mpl/if.hpp>
00030 #include <boost/mpl/plus.hpp>
00031 #include <boost/mpl/push_back.hpp>
00032 #include <boost/mpl/vector.hpp>
00033 #include "gil_config.hpp"
00034 #include "pixel.hpp"
00035 #include "channel.hpp"
00036
00037 namespace boost { namespace gil {
00038
00040
00041
00042
00044
00045 template <int RangeSize, bool Mutable>
00046 class bit_range {
00047 public:
00048 typedef typename mpl::if_c<Mutable,unsigned char,const unsigned char>::type byte_t;
00049 typedef std::ptrdiff_t difference_type;
00050 template <int RS, bool M> friend class bit_range;
00051 private:
00052 byte_t* _current_byte;
00053 int _bit_offset;
00054
00055 public:
00056 bit_range() : _current_byte(NULL), _bit_offset(0) {}
00057 bit_range(byte_t* current_byte, int bit_offset) : _current_byte(current_byte), _bit_offset(bit_offset) { assert(bit_offset>=0 && bit_offset<8); }
00058
00059 bit_range(const bit_range& br) : _current_byte(br._current_byte), _bit_offset(br._bit_offset) {}
00060 template <bool M> bit_range(const bit_range<RangeSize,M>& br) : _current_byte(br._current_byte), _bit_offset(br._bit_offset) {}
00061
00062 bit_range& operator=(const bit_range& br) { _current_byte = br._current_byte; _bit_offset=br._bit_offset; return *this; }
00063 bool operator==(const bit_range& br) const { return _current_byte==br._current_byte && _bit_offset==br._bit_offset; }
00064
00065 bit_range& operator++() {
00066 _current_byte += (_bit_offset+RangeSize) / 8;
00067 _bit_offset = (_bit_offset+RangeSize) % 8;
00068 return *this;
00069 }
00070 bit_range& operator--() { bit_advance(-RangeSize); return *this; }
00071
00072 void bit_advance(difference_type num_bits) {
00073 int new_offset = int(_bit_offset+num_bits);
00074 _current_byte += new_offset / 8;
00075 _bit_offset = new_offset % 8;
00076 if (_bit_offset<0) {
00077 _bit_offset+=8;
00078 --_current_byte;
00079 }
00080 }
00081 difference_type bit_distance_to(const bit_range& b) const {
00082 return (b.current_byte() - current_byte())*8 + b.bit_offset()-bit_offset();
00083 }
00084 byte_t* current_byte() const { return _current_byte; }
00085 int bit_offset() const { return _bit_offset; }
00086 };
00087
00088
00092
00116
00117
00118 template <typename ChannelBitSizes,
00119 typename Layout,
00120 bool IsMutable>
00121 struct bit_aligned_pixel_reference {
00122 BOOST_STATIC_CONSTANT(int, bit_size = (mpl::accumulate<ChannelBitSizes, mpl::int_<0>, mpl::plus<mpl::_1, mpl::_2> >::type::value));
00123 typedef bit_range<bit_size,IsMutable> bit_range_t;
00124 typedef typename detail::min_fast_uint<bit_size>::type bitfield_t;
00125 typedef typename mpl::if_c<IsMutable,unsigned char*,const unsigned char*>::type data_ptr_t;
00126
00127 typedef Layout layout_t;
00128
00129 typedef typename packed_pixel_type<bitfield_t,ChannelBitSizes,Layout>::type value_type;
00130 typedef const bit_aligned_pixel_reference reference;
00131 typedef const bit_aligned_pixel_reference<ChannelBitSizes,Layout,false> const_reference;
00132
00133 BOOST_STATIC_CONSTANT(bool, is_mutable = IsMutable);
00134
00135 bit_aligned_pixel_reference(){}
00136 bit_aligned_pixel_reference(data_ptr_t data_ptr, int bit_offset) : _bit_range(data_ptr, bit_offset) {}
00137 explicit bit_aligned_pixel_reference(const bit_range_t& bit_range) : _bit_range(bit_range) {}
00138 template <bool IsMutable2> bit_aligned_pixel_reference(const bit_aligned_pixel_reference<ChannelBitSizes,Layout,IsMutable2>& p) : _bit_range(p._bit_range) {}
00139
00140
00141 explicit bit_aligned_pixel_reference(const typename kth_element_type<bit_aligned_pixel_reference,0>::type channel0) : _bit_range(static_cast<data_ptr_t>(&channel0), channel0.first_bit()) {
00142 BOOST_STATIC_ASSERT((num_channels<bit_aligned_pixel_reference>::value==1));
00143 }
00144
00145
00146 bit_aligned_pixel_reference(const bit_aligned_pixel_reference& p) : _bit_range(p._bit_range) {}
00147 template <typename BF, typename CR> bit_aligned_pixel_reference(packed_pixel<BF,CR,Layout>& p) : _bit_range(static_cast<data_ptr_t>(&at_c<0>(p)), at_c<0>(p).first_bit()) {
00148 check_compatible<packed_pixel<BF,CR,Layout> >();
00149 }
00150
00151 template <typename P> const bit_aligned_pixel_reference& operator=(const P& p) const { check_compatible<P>(); static_copy(p,*this); return *this; }
00152 const bit_aligned_pixel_reference& operator=(const bit_aligned_pixel_reference& p) const { static_copy(p,*this); return *this; }
00153
00154 template <typename P> bool operator==(const P& p) const { check_compatible<P>(); return static_equal(*this,p); }
00155 template <typename P> bool operator!=(const P& p) const { return !(*this==p); }
00156
00157 const bit_aligned_pixel_reference* operator->() const { return this; }
00158
00159 const bit_range_t& bit_range() const { return _bit_range; }
00160 private:
00161 mutable bit_range_t _bit_range;
00162 template <typename C, typename L, bool M> friend struct bit_aligned_pixel_reference;
00163
00164 template <typename Pixel> static void check_compatible() { gil_function_requires<PixelsCompatibleConcept<Pixel,bit_aligned_pixel_reference> >(); }
00165 };
00166
00168
00170
00171 template <typename ChannelBitSizes, typename L, bool IsMutable, int K>
00172 struct kth_element_type<bit_aligned_pixel_reference<ChannelBitSizes,L,IsMutable>, K> {
00173 private:
00174 typedef typename bit_aligned_pixel_reference<ChannelBitSizes,L,IsMutable>::bitfield_t bitfield_t;
00175 public:
00176 typedef const packed_dynamic_channel_reference<bitfield_t, mpl::at_c<ChannelBitSizes,K>::type::value, IsMutable> type;
00177 };
00178
00179 template <typename C, typename L, bool M, int K>
00180 struct kth_element_reference_type<bit_aligned_pixel_reference<C,L,M>, K>
00181 : public kth_element_type<bit_aligned_pixel_reference<C,L,M>, K> {};
00182
00183 template <typename C, typename L, bool M, int K>
00184 struct kth_element_const_reference_type<bit_aligned_pixel_reference<C,L,M>, K>
00185 : public kth_element_type<bit_aligned_pixel_reference<C,L,M>, K> {};
00186
00187
00188 namespace detail {
00189
00190 template <typename IntegralVector, int K>
00191 struct sum_k : public mpl::plus<sum_k<IntegralVector,K-1>, typename mpl::at_c<IntegralVector,K-1>::type > {};
00192
00193 template <typename IntegralVector> struct sum_k<IntegralVector,0> : public mpl::int_<0> {};
00194 }
00195
00196
00197 template <int K, typename ChannelBitSizes, typename L, bool Mutable> inline
00198 typename kth_element_reference_type<bit_aligned_pixel_reference<ChannelBitSizes,L,Mutable>,K>::type
00199 at_c(const bit_aligned_pixel_reference<ChannelBitSizes,L,Mutable>& p) {
00200 typedef bit_aligned_pixel_reference<ChannelBitSizes,L,Mutable> pixel_t;
00201 typedef typename kth_element_reference_type<pixel_t,K>::type channel_t;
00202 typedef typename pixel_t::bit_range_t bit_range_t;
00203
00204 bit_range_t bit_range(p.bit_range());
00205 bit_range.bit_advance(detail::sum_k<ChannelBitSizes,K>::value);
00206
00207 return channel_t(bit_range.current_byte(), bit_range.bit_offset());
00208 }
00209
00211
00213
00215 template <typename C, typename L, bool M>
00216 struct is_pixel<bit_aligned_pixel_reference<C,L,M> > : public mpl::true_{};
00217
00219
00221
00222 template <typename C, typename L, bool M>
00223 struct color_space_type<bit_aligned_pixel_reference<C,L,M> > {
00224 typedef typename L::color_space_t type;
00225 };
00226
00227 template <typename C, typename L, bool M>
00228 struct channel_mapping_type<bit_aligned_pixel_reference<C,L,M> > {
00229 typedef typename L::channel_mapping_t type;
00230 };
00231
00232 template <typename C, typename L, bool M>
00233 struct is_planar<bit_aligned_pixel_reference<C,L,M> > : mpl::false_ {};
00234
00236
00238
00239 namespace detail {
00240
00241 template <unsigned K, typename T> struct k_copies;
00242 template <typename T> struct k_copies<0,T> {
00243 typedef mpl::vector0<> type;
00244 };
00245 template <unsigned K, typename T> struct k_copies : public mpl::push_back<typename k_copies<K-1,T>::type, T> {};
00246 }
00247
00248
00249
00250 template <typename BitField, int NumBits, typename Layout>
00251 struct pixel_reference_type<const packed_dynamic_channel_reference<BitField,NumBits,false>, Layout, false, false> {
00252 private:
00253 typedef typename mpl::size<typename Layout::color_space_t>::type size_t;
00254 typedef typename detail::k_copies<size_t::value,mpl::integral_c<unsigned,NumBits> >::type channel_bit_sizes_t;
00255 public:
00256 typedef bit_aligned_pixel_reference<channel_bit_sizes_t, Layout, false> type;
00257 };
00258
00259
00260
00261 template <typename BitField, int NumBits, typename Layout>
00262 struct pixel_reference_type<const packed_dynamic_channel_reference<BitField,NumBits,true>, Layout, false, true> {
00263 private:
00264 typedef typename mpl::size<typename Layout::color_space_t>::type size_t;
00265 typedef typename detail::k_copies<size_t::value,mpl::integral_c<unsigned,NumBits> >::type channel_bit_sizes_t;
00266 public:
00267 typedef bit_aligned_pixel_reference<channel_bit_sizes_t, Layout, true> type;
00268 };
00269
00270 } }
00271
00272 namespace std {
00273
00274
00275
00276
00277
00278
00279
00280 template <typename C, typename L, typename R> inline
00281 void swap(boost::gil::bit_aligned_pixel_reference<C,L,true> x, R& y) {
00282 boost::gil::swap_proxy<typename boost::gil::bit_aligned_pixel_reference<C,L,true>::value_type>(x,y);
00283 }
00284
00285
00286 template <typename C, typename L> inline
00287 void swap(typename boost::gil::bit_aligned_pixel_reference<C,L,true>::value_type& x, boost::gil::bit_aligned_pixel_reference<C,L,true> y) {
00288 boost::gil::swap_proxy<typename boost::gil::bit_aligned_pixel_reference<C,L,true>::value_type>(x,y);
00289 }
00290
00291
00292 template <typename C, typename L> inline
00293 void swap(boost::gil::bit_aligned_pixel_reference<C,L,true> x, boost::gil::bit_aligned_pixel_reference<C,L,true> y) {
00294 boost::gil::swap_proxy<typename boost::gil::bit_aligned_pixel_reference<C,L,true>::value_type>(x,y);
00295 }
00296 }
00297 #endif