[Boost-commit] svn:boost r83141 - in trunk/boost/gil/extension/io: detail formats/targa

Subject: [Boost-commit] svn:boost r83141 - in trunk/boost/gil/extension/io: detail formats/targa
From: chhenning_at_[hidden]
Date: 2013-02-24 16:06:55

Author: chhenning
Date: 2013-02-24 16:06:54 EST (Sun, 24 Feb 2013)
New Revision: 83141
URL: http://svn.boost.org/trac/boost/changeset/83141

Log:
Using iterator_facade as base for scanline_read_iterator.
Text files modified: 
   trunk/boost/gil/extension/io/detail/scanline_read_iterator.hpp |    94 ++++++++++++++------------------------- 
   trunk/boost/gil/extension/io/formats/targa/scanline_read.hpp   |     4 +                                       
   2 files changed, 36 insertions(+), 62 deletions(-)

Modified: trunk/boost/gil/extension/io/detail/scanline_read_iterator.hpp
==============================================================================
--- trunk/boost/gil/extension/io/detail/scanline_read_iterator.hpp	(original)
+++ trunk/boost/gil/extension/io/detail/scanline_read_iterator.hpp	2013-02-24 16:06:54 EST (Sun, 24 Feb 2013)
@@ -13,13 +13,15 @@
 ////////////////////////////////////////////////////////////////////////////////////////
 /// \file
 /// \brief
-/// \author Christian Henning \n
+/// \author Christian Henning
 ///
 /// \date 2012 \n
 ///
 ////////////////////////////////////////////////////////////////////////////////////////
 
-#include <vector>
+#include <boost/shared_ptr.hpp>
+#include <boost/make_shared.hpp>
+#include <boost/iterator/iterator_facade.hpp>
 
 #include <boost/gil/extension/io/detail/io_error.hpp>
 
@@ -32,106 +34,76 @@
 
 /// Input iterator to read images.
 template< typename Reader >
-class scanline_read_iterator
+class scanline_read_iterator : public boost::iterator_facade< scanline_read_iterator< Reader >
+                                                            , byte_t*
+                                                            , std::input_iterator_tag
+                                                            >
 {
 public:
 
-    typedef typename Reader::backend_t backend_t;
-
-    typedef std::input_iterator_tag iterator_category;
-    typedef byte_t* value_type;
-    typedef value_type const* pointer;
-    typedef value_type const& reference;
-    typedef int difference_type;
-    
-public:
-
-    /// Constructor with preallocated image. Reading starts at first scanline of source image.
     scanline_read_iterator( Reader& reader
-                          , int pos = 0
+                          , int     pos = 0
                           )
     : _pos( pos )
     , _read_scanline( true )
     , _skip_scanline( true )
     , _reader( reader )
     {
-        init();
-    }
-
-    /// Dereference Operator
-    reference operator*()
-    {
-        if( _read_scanline == true )
-        {
-            _reader.read( _buffer_start
-                        , _pos
-                        );
-        }
-
-        _skip_scanline = false;
-        _read_scanline = false;
-
-        return _buffer_start;
+        _buffer = boost::make_shared<  buffer_t >( buffer_t( _reader._scanline_length ));
+        _buffer_start = &_buffer->front();
     }
 
-    /// Pointer-To-Memper Operator.
-    pointer operator->() const
-    {
-        return &(operator*());
-    }
+private:
+    friend class boost::iterator_core_access;
 
-    /// Pre-Increment Operator
-    scanline_read_iterator< Reader >& operator++()
+    void increment()
     {
         if( _skip_scanline == true )
         {
-            _skip();
+            _reader.skip( _buffer_start
+                        , _pos
+                        );
         }
 
         ++_pos;
 
         _skip_scanline = true;
         _read_scanline = true;
-
-        return (*this);
     }
 
-    bool operator ==( const scanline_read_iterator< Reader >& rhs ) const
+    bool equal( const scanline_read_iterator& rhs ) const
     {
         return _pos == rhs._pos;
     }
 
-    bool operator !=( const scanline_read_iterator< Reader >& rhs ) const
+    reference dereference() const
     {
-        return _pos < rhs._pos;
-    }
-
-private:
+        if( _read_scanline == true )
+        {
+            _reader.read( _buffer_start
+                        , _pos
+                        );
+        }
 
-    void init()
-    {
-        _buffer = std::vector< byte_t >( _reader._scanline_length );
-        _buffer_start = &_buffer.front();
-    }
+        _skip_scanline = false;
+        _read_scanline = false;
 
-    void _skip()
-    {
-        _reader.skip( _buffer_start
-                    , _pos
-                    );
+        return _buffer_start;
     }
 
 private:
+    Reader& _reader;
 
     mutable int _pos;
 
     mutable bool _read_scanline;
     mutable bool _skip_scanline;
 
-    Reader& _reader;
+    typedef std::vector< byte_t > buffer_t;
+    typedef boost::shared_ptr< buffer_t > buffer_ptr_t;
 
-    std::vector< byte_t > _buffer;
-    byte_t*               _buffer_start;
+    buffer_ptr_t _buffer;
+    mutable byte_t* _buffer_start;
 };
 
 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) 

Modified: trunk/boost/gil/extension/io/formats/targa/scanline_read.hpp
==============================================================================
--- trunk/boost/gil/extension/io/formats/targa/scanline_read.hpp	(original)
+++ trunk/boost/gil/extension/io/formats/targa/scanline_read.hpp	2013-02-24 16:06:54 EST (Sun, 24 Feb 2013)
@@ -91,7 +91,9 @@
     /// Skip over a scanline.
     void skip( byte_t*, int )
     {
-        this->_io_dev.seek( static_cast<long>( this->_scanline_length ), SEEK_CUR );
+        this->_io_dev.seek( static_cast<long>( this->_scanline_length )
+                          , SEEK_CUR
+                          );
     }
 
     iterator_t begin() { return iterator_t( *this ); }