background_wnd/painters/ipicture_painter.hpp

// ipicture_painter.hpp

// Copyright (C) 2004 Steven Weiß (steven11@gmx.de)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.


#pragma once
#include <background_wnd/detail/include.hpp>
#include <background_wnd/painter_base.hpp>
#include <background_wnd/detail/ipicture.hpp>
#include <background_wnd/detail/general_exception.hpp>


namespace win32 { namespace gui {

namespace detail {

     // implementation of ipicture_painter_base
     struct ipicture_painter_base_impl
     {         
          typedef const std::string& param0;

          bool load_file(const std::string& file_name);     
          const bg_wnd::ipicture& get_ipicture() const;     
          void draw_picture(HDC hDC, int x, int y, int cx, int cy);
          
     private:
          bg_wnd::ipicture picture_;    
     };

     // base of the ipicture_painters. note how the exception is specified for the Derived class ;-)
     template <class Derived>
     struct ipicture_painter_base : painter_base
     {    
          typedef ipicture_painter_base_impl::param0 param0;

          // exceptions
          typedef bg_wnd::general_exception<Derived, 0> file_not_found;
          
          ipicture_painter_base(const std::string& file_name)
          {
               load_file(file_name);
          }

          virtual ~ipicture_painter_base()
          {}

          void load_file(const std::string& file_name)
          {
               if (!file_name.empty() && impl_.load_file(file_name) == false)
                    throw file_not_found(static_cast<Derived&> (*this));   // class is abstract (draw() not implemented)
          }                                                                               // so this is safe

          const bg_wnd::ipicture& get_ipicture() const
          {
               return impl_.get_ipicture();
          }

     protected:     
          void draw_picture(HDC hDC, int x, int y, int cx, int cy)
          {
               impl_.draw_picture(hDC, x, y, cx, cy);
          }
          
     private:
          ipicture_painter_base_impl impl_;  
     };

}    // namespace detail

// ========================================================================================================= //

class ipicture_painter : public detail::ipicture_painter_base<ipicture_painter>
{
     typedef detail::ipicture_painter_base<ipicture_painter> Base;

public:
     // c'tor
     ipicture_painter(const std::string& file_name = "");             

     // virtual functions of painter_base
     ipicture_painter* clone() const;
     void draw(HDC hDC, int cx, int cy);     
};

// ========================================================================================================= //

class tile_ipicture_painter : public detail::ipicture_painter_base<tile_ipicture_painter>
{
     typedef detail::ipicture_painter_base<tile_ipicture_painter> Base;
     SIZE tile_size_;

public:
     typedef SIZE param1;

     // c'tor
     tile_ipicture_painter(const std::string& file_name = "");             
     tile_ipicture_painter(const std::string& file_name, SIZE tile_size);
     
     // virtual functions of painter_base
     tile_ipicture_painter* clone() const;   
     void draw(HDC hDC, int cx, int cy);          

     // own functions
     void tile_size(SIZE tile_size);
     SIZE tile_size() const;
};

} }  // namespace win32::gui

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