agg/inc/agg_bitset_iterator.h

   1 //----------------------------------------------------------------------------
   2 // Anti-Grain Geometry - Version 2.3
   3 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
   4 //
   5 // Permission to copy, use, modify, sell and distribute this software
   6 // is granted provided this copyright notice appears in all copies.
   7 // This software is provided "as is" without express or implied
   8 // warranty, and with no claim as to its suitability for any purpose.
   9 //
  10 //----------------------------------------------------------------------------
  11 // Contact: mcseem@antigrain.com
  12 //          mcseemagg@yahoo.com
  13 //          http://www.antigrain.com
  14 //----------------------------------------------------------------------------
  15
  16 #ifndef AGG_BITSET_ITERATOR_INCLUDED
  17 #define AGG_BITSET_ITERATOR_INCLUDED
  18
  19 #include "agg_basics.h"
  20
  21 namespace agg
  22 {
  23
  24     class bitset_iterator
  25     {
  26     public:
  27         bitset_iterator(const int8u* bits, unsigned offset = 0) :
  28             m_bits(bits + (offset >> 3)),
  29             m_mask(0x80 >> (offset & 7))
  30         {}
  31
  32         void operator ++ ()
  33         {
  34             m_mask >>= 1;
  35             if(m_mask == 0)
  36             {
  37                 ++m_bits;
  38                 m_mask = 0x80;
  39             }
  40         }
  41
  42         unsigned bit() const
  43         {
  44             return (*m_bits) & m_mask;
  45         }
  46
  47     private:
  48         const int8u* m_bits;
  49         int8u        m_mask;
  50     };
  51
  52 }
  53
  54 #endif