WIP. Scale cover art option. Seems to work

2014-06-14 20:44:03 +02:00
parent 1d67a548c9
commit 9bada5ee2a
92 changed files with 15866 additions and 1890 deletions
@@ -0,0 +1,140 @@
+/*
+    Copyright 2007-2008 Christian Henning
+    Use, modification and distribution are subject to the Boost Software License,
+    Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+    http://www.boost.org/LICENSE_1_0.txt).
+*/
+
+/*************************************************************************************************/
+
+#ifndef BOOST_GIL_EXTENSION_IO_DETAIL_READER_BASE_HPP
+#define BOOST_GIL_EXTENSION_IO_DETAIL_READER_BASE_HPP
+
+////////////////////////////////////////////////////////////////////////////////////////
+/// \file
+/// \brief
+/// \author Christian Henning \n
+///
+/// \date   2007-2008 \n
+///
+////////////////////////////////////////////////////////////////////////////////////////
+
+#include "base.hpp"
+
+namespace boost { namespace gil { namespace detail {
+
+/// Reader Base Class
+/// 
+/// It provides some basic functionality which is shared for all readers.
+/// For instance, it recreates images when necessary. It checks whether
+/// user supplied coordinates are valid.
+///
+/// @tparam FormatTag        A format tag, like jpeg_tag.
+/// @tparam ConversionPolicy Conversion policy, see coversion_policies.hpp.
+template< typename FormatTag
+        , typename ConversionPolicy
+        >
+struct reader_base
+{
+public:
+
+    /// Initializes an image. But also does some check ups.
+    ///
+    /// @tparam Image Image which implements boost::gil's ImageConcept.
+    ///
+    /// @param img  The image.
+    /// @param info The image read info.
+    template< typename Image >
+    void init_image( Image&                              img
+                   , const image_read_info< FormatTag >& info
+                   )
+    {
+        _info = info;
+
+        setup( _settings._dim );
+
+        img.recreate( _settings._dim.x
+                    , _settings._dim.y
+                    );
+    }
+
+    template< typename View >
+    void init_view( const View&                         view
+                  , const image_read_info< FormatTag >& info
+                  )
+    {
+        _info = info;
+
+        setup( view.dimensions() );
+    }
+
+protected:
+
+    reader_base( const image_read_settings< FormatTag >& settings )
+    : _settings( settings )
+    {}
+    reader_base( const typename ConversionPolicy::color_converter_type& cc
+               , const image_read_settings< FormatTag >&                settings
+               )
+    : _settings( settings )
+    , _cc_policy( cc )
+    {}
+
+private:
+
+    void setup( const point_t& dim )
+    {
+        check_coordinates( dim );
+
+        if( dim == point_t( 0, 0 ))
+        {
+            _settings._dim.x = _info._width;
+            _settings._dim.y = _info._height;
+        }
+        else
+        {
+            _settings._dim = dim;
+        }
+    }
+
+    void check_coordinates( const point_t& dim )
+    {
+       typedef point_t::value_type int_t;
+
+       int_t width  = static_cast< int_t >( _info._width  );
+       int_t height = static_cast< int_t >( _info._height );
+
+       io_error_if( (  _settings._top_left.x < 0
+                    || _settings._top_left.y < 0
+                    || dim.x < 0
+                    || dim.y < 0
+                    )
+                 , "User provided view has incorrect size." );
+
+
+       io_error_if( (  ( width  ) <  _settings._top_left.x
+                    && ( width  ) <= dim.x
+                    && ( height ) <  _settings._top_left.y
+                    && ( height ) <= dim.y  )
+                 , "User provided view has incorrect size."       );
+
+       io_error_if( (  ( _settings._top_left.x + dim.x ) > width
+                    || ( _settings._top_left.y + dim.y ) > height
+                   )
+                 , "User provided view has incorrect size." );
+
+    }
+
+protected:
+
+    image_read_settings< FormatTag > _settings;
+    image_read_info< FormatTag >     _info;
+
+    ConversionPolicy _cc_policy;
+};
+
+} // namespace detail
+} // namespace gil
+} // namespace boost
+
+#endif // BOOST_GIL_EXTENSION_IO_DETAIL_READER_BASE_HPP