Index: src/graphics.h.in
===================================================================
RCS file: /cvs/octave/src/graphics.h.in,v
retrieving revision 1.47
diff -c -p -r1.47 graphics.h.in
*** src/graphics.h.in	19 Jan 2008 07:39:17 -0000	1.47
--- src/graphics.h.in	22 Jan 2008 13:57:27 -0000
*************** public:
*** 1052,1058 ****
    octave_value get_uicontextmenu (void) const { return uicontextmenu.get (); }
  
    octave_value get_userdata (void) const { return userdata.get (); }
!   
    std::string get_visible (void) const { return visible.current_value (); }
  
    bool is_beingdeleted (void) const { return beingdeleted.is_on (); }
--- 1052,1059 ----
    octave_value get_uicontextmenu (void) const { return uicontextmenu.get (); }
  
    octave_value get_userdata (void) const { return userdata.get (); }
!  
!   bool is_visible (void) const { return visible.is_on (); }
    std::string get_visible (void) const { return visible.current_value (); }
  
    bool is_beingdeleted (void) const { return beingdeleted.is_on (); }
*************** public:
*** 1071,1076 ****
--- 1072,1079 ----
  
    void set_parent (const octave_value& val);
  
+   void set_modified (const octave_value& val) { __modified__ = val; }
+ 
    void set_busyaction (const octave_value& val)
    {
      if (! error_state)
*************** private:
*** 1632,1637 ****
--- 1635,1755 ----
  
  // ---------------------------------------------------------------------
  
+ class graphics_backend;
+ 
+ class base_graphics_backend
+ {
+ public:
+   friend class graphics_backend;
+ 
+ public:
+   base_graphics_backend (const std::string& nm)
+       : name (nm), count (0) { }
+ 
+   virtual ~base_graphics_backend (void) { }
+ 
+   std::string get_name (void) const { return name; }
+ 
+   virtual bool is_valid (void) const { return false; }
+ 
+   virtual void close_figure (const octave_value&) const
+     { error ("close_figure: invalid graphics backend"); }
+ 
+   virtual void redraw_figure (const graphics_handle&) const
+     { error ("redraw_figure: invalid graphics backend"); }
+ 
+   virtual void print_figure (const graphics_handle&, const std::string&,
+ 			     const std::string&, bool,
+ 			     const std::string& = "") const
+     { error ("print_figure: invalid graphics backend"); }
+ 
+   virtual Matrix get_canvas_size (const graphics_handle&) const
+     {
+       error ("get_canvas_size: invalid graphics backend");
+       return Matrix (1, 2, 0.0);
+     }
+ 
+ private:
+   std::string name;
+   int count;
+ };
+ 
+ class graphics_backend
+ {
+ public:
+   graphics_backend (void)
+       : rep (new base_graphics_backend ("unknown"))
+     {
+       rep->count++;
+     }
+ 
+   graphics_backend (base_graphics_backend* b)
+       : rep (b)
+     {
+       rep->count++;
+     }
+ 
+   graphics_backend (const graphics_backend& b)
+       : rep (b.rep)
+     {
+       rep->count++;
+     }
+ 
+   ~graphics_backend (void)
+     {
+       if (--rep->count == 0)
+ 	delete rep;
+     }
+ 
+   graphics_backend& operator = (const graphics_backend& b)
+     {
+       if (rep != b.rep)
+ 	{
+ 	  if (--rep->count == 0)
+ 	    delete rep;
+ 
+ 	  rep = b.rep;
+ 	  rep->count++;
+ 	}
+ 
+       return *this;
+     }
+ 
+   operator bool (void) const { return rep->is_valid (); }
+ 
+   std::string get_name (void) const { return rep->get_name (); }
+ 
+   void close_figure (const octave_value& pstream) const
+     { rep->close_figure (pstream); }
+ 
+   void redraw_figure (const graphics_handle& fh) const
+     { rep->redraw_figure (fh); }
+   
+   void print_figure (const graphics_handle& fh, const std::string& term,
+ 		     const std::string& file, bool mono,
+ 		     const std::string& debug_file = "") const
+     { rep->print_figure (fh, term, file, mono, debug_file); }
+ 
+   Matrix get_canvas_size (const graphics_handle& fh) const
+     { return rep->get_canvas_size (fh); }
+ 
+   OCTINTERP_API static graphics_backend default_backend (void);
+ 
+   static void register_backend (const graphics_backend& b)
+     { available_backends[b.get_name ()] = b; }
+ 
+   static void unregister_backend (const std::string& name)
+     { available_backends.erase (name); }
+ 
+ private:
+   base_graphics_backend *rep;
+ 
+ private:
+   static std::map<std::string, graphics_backend> available_backends;
+ };
+ 
+ // ---------------------------------------------------------------------
+ 
  class OCTINTERP_API root_figure : public base_graphics_object
  {
  public:
*************** public:
*** 1744,1752 ****
    class properties : public base_properties
    {
    public:
!     void close (void);
      void set_visible (const octave_value& val);
  
      // See the genprops.awk script for an explanation of the
      // properties declarations.
  
--- 1862,1881 ----
    class properties : public base_properties
    {
    public:
!     void close (bool pop = true);
! 
      void set_visible (const octave_value& val);
  
+     graphics_backend get_backend (void) const
+       {
+ 	if (! backend)
+ 	  backend = graphics_backend::default_backend ();
+ 
+ 	return backend;
+       }
+ 
+     void set_backend (const graphics_backend& b) { backend = b; }
+ 
      // See the genprops.awk script for an explanation of the
      // properties declarations.
  
*************** public:
*** 1813,1818 ****
--- 1942,1950 ----
  	pointershapehotspot.add_constraint (dim_vector (1, 2));
  	position.add_constraint (dim_vector (1, 4));
        }
+ 
+   private:
+     mutable graphics_backend backend;
    };
  
  private:
*************** public:
*** 1881,1886 ****
--- 2013,2024 ----
  
    bool valid_object (void) const { return true; }
  
+   graphics_backend get_backend (void) const
+     { return xproperties.get_backend (); }
+ 
+   void set_backend (const graphics_backend& b)
+     { xproperties.set_backend (b); }
+ 
  private:
    property_list default_properties;
  };
Index: src/graphics.cc
===================================================================
RCS file: /cvs/octave/src/graphics.cc,v
retrieving revision 1.76
diff -c -p -r1.76 graphics.cc
*** src/graphics.cc	19 Jan 2008 06:08:03 -0000	1.76
--- src/graphics.cc	22 Jan 2008 13:57:27 -0000
*************** along with Octave; see the file COPYING.
*** 43,48 ****
--- 43,50 ----
  #include "ov-fcn-handle.h"
  #include "parse.h"
  #include "unwind-prot.h"
+ #include "file-ops.h"
+ #include "file-stat.h"
  
  static void
  gripe_set_invalid (const std::string& pname)
*************** base_properties::delete_children (void)
*** 1146,1151 ****
--- 1148,1216 ----
  
  // ---------------------------------------------------------------------
  
+ class gnuplot_backend : public base_graphics_backend
+ {
+ public:
+   gnuplot_backend (void)
+       : base_graphics_backend ("gnuplot") { }
+ 
+   ~gnuplot_backend (void) { }
+ 
+   bool is_valid (void) const { return true; }
+  
+   void close_figure (const octave_value& pstream) const
+     {
+       if (! pstream.is_empty())
+ 	{
+ 	  octave_value_list args;
+ 	  args(1) = "\nquit;\n";
+ 	  args(0) = pstream;
+ 	  feval ("fputs", args);
+ 	  args.resize (1);
+ 	  feval ("fflush", args);
+ 	  feval ("pclose", args);
+ 	}
+     }
+ 
+   void redraw_figure (const graphics_handle& fh) const
+     {
+       octave_value_list args;
+       args(0) = fh.as_octave_value ();
+       feval ("gnuplot_drawnow", args);
+     }
+ 
+   void print_figure (const graphics_handle& fh, const std::string& term,
+ 		     const std::string& file, bool mono,
+ 		     const std::string& debug_file) const
+     {
+       octave_value_list args;
+       args.resize (4);
+       args(0) = fh.as_octave_value ();
+       args(1) = term;
+       args(2) = file;
+       args(3) = mono;
+       if (! debug_file.empty ())
+ 	args(4) = debug_file;
+       feval ("gnuplot_drawnow", args);
+     }
+ 
+   Matrix get_canvas_size (const graphics_handle& fh) const
+     { return Matrix (1, 2, 0.0); }
+ };
+ 
+ graphics_backend
+ graphics_backend::default_backend (void)
+ {
+   if (available_backends.size () == 0)
+     register_backend (new gnuplot_backend ());
+ 
+   return available_backends["gnuplot"];
+ }
+ 
+ std::map<std::string, graphics_backend> graphics_backend::available_backends;
+ 
+ // ---------------------------------------------------------------------
+ 
  #include "graphics-props.cc"
  
  // ---------------------------------------------------------------------
*************** figure::properties::set_visible (const o
*** 1202,1225 ****
  }
  
  void
! figure::properties::close (void)
  {
!   if (! get___plot_stream__ ().is_empty ())
!     {
!       octave_value_list args;
!       args(1) = "\nquit;\n";
!       args(0) = get___plot_stream__ ();
!       feval ("fputs", args);
!       args.resize (1);
!       feval ("fflush", args);
!       feval ("pclose", args);
!     }
  
!   gh_manager::pop_figure (__myhandle__);
  
!   graphics_handle cf = gh_manager::current_figure ();
  
!   xset (0, "currentfigure", cf.value ());
  }
  
  octave_value
--- 1267,1285 ----
  }
  
  void
! figure::properties::close (bool pop)
  {
!   if (backend)
!     backend.close_figure (get___plot_stream__ ());
  
!   if (pop)
!     {
!       gh_manager::pop_figure (__myhandle__);
  
!       graphics_handle cf = gh_manager::current_figure ();
  
!       xset (0, "currentfigure", cf.value ());
!     }
  }
  
  octave_value
*************** Undocumented internal function.\n\
*** 2305,2310 ****
--- 2365,2494 ----
    return octave_value (gh_manager::figure_handle_list ());
  }
  
+ DEFUN (drawnow, args, ,
+    "-*- texinfo -*-\n\
+ @deftypefn {Built-in Function} {} __go_drawnow__ ()\n\
+ @deftypefnx {Built-in Function} {} __go_drawnow__ (@var{term}, @var{file}, @var{mono}, @var{debug_file})\n\
+ Undocumented internal function.\n\
+ @end deftypefn")
+ {
+   static int drawnow_executing = 0;
+   static bool __go_close_all_registered__ = false;
+ 
+   octave_value retval;
+ 
+   if (drawnow_executing >= 1)
+     return retval;
+ 
+   if (! __go_close_all_registered__)
+     {
+       // FIXME: is there a C++ way to do this?
+       int parse_status;
+       eval_string ("atexit (\"__go_close_all__\")", true, parse_status);
+       __go_close_all_registered__ = true;
+     }
+ 
+   ++drawnow_executing;
+ 
+   if (args.length () == 0)
+     {
+       Matrix hlist = gh_manager::figure_handle_list ();
+ 
+       for (int i = 0; ! error_state && i < hlist.length (); i++)
+ 	{
+ 	  graphics_handle h = gh_manager::lookup (hlist(i));
+ 
+ 	  if (h.ok () && h != 0)
+ 	    {
+ 	      graphics_object go = gh_manager::get_object (h);
+ 	      figure::properties& fprops = dynamic_cast <figure::properties&> (go.get_properties ());
+ 
+ 	      if (fprops.is_modified ())
+ 		{
+ 		  if (fprops.is_visible ())
+ 		    fprops.get_backend ().redraw_figure (h);
+ 		  else if (! fprops.get___plot_stream__ ().is_empty ())
+ 		    {
+ 		      fprops.close (false);
+ 		      fprops.set___plot_stream__ (Matrix ());
+ 		      fprops.set___enhanced__ (false);
+ 		    }
+ 		  fprops.set_modified (false);
+ 		}
+ 	    }
+ 	}
+     }
+   else if (args.length () >= 2 && args.length () <= 4)
+     {
+       std::string term, file, debug_file;
+       bool mono;
+ 
+       term = args(0).string_value ();
+ 
+       if (! error_state)
+ 	{
+ 	  file = args(1).string_value ();
+ 
+ 	  if (! error_state)
+ 	    {
+ 	      int pos = file.find_last_of (file_ops::dir_sep_chars);
+ 
+ 	      if (pos != NPOS)
+ 		{
+ 		  file_stat fs (file.substr (0, pos));
+ 
+ 		  if (! (fs && fs.is_dir ()))
+ 		    error ("drawnow: nonexistent directory `%s'",
+ 			   file.substr (0, pos).c_str ());
+ 		}
+ 
+ 	      mono = (args.length () >= 3 ? args(2).bool_value () : false);
+ 
+ 	      if (! error_state)
+ 		{
+ 		  debug_file = (args.length () > 3 ? args(3).string_value ()
+ 				: "");
+ 
+ 		  if (! error_state)
+ 		    {
+ 		      graphics_handle h = gcf ();
+ 
+ 		      if (h.ok ())
+ 			{
+ 			  graphics_object go = gh_manager::get_object (h);
+ 			  figure::properties& fprops = dynamic_cast<figure::properties&> (go.get_properties ());
+ 
+ 			  fprops.get_backend ()
+ 			      .print_figure (h, term, file, mono, debug_file);
+ 			}
+ 		      else
+ 			error ("drawnow: nothing to draw");
+ 		    }
+ 		  else
+ 		    error ("drawnow: invalid debug_file, expected a string value");
+ 		}
+ 	      else
+ 		error ("drawnow: invalid colormode, expected a boolean value");
+ 	    }
+ 	  else
+ 	    error ("drawnow: invalid file, expected a string value");
+ 	}
+       else
+ 	error ("drawnow: invalid terminal, expected a string value");
+     }
+   else
+     print_usage ();
+ 
+   // FIXME: is there a C++ way to do this?
+   octave_value_list fargs;
+   fargs(0) = false;
+   feval ("__request_drawnow__", fargs);
+ 
+   --drawnow_executing;
+ 
+   return retval;
+ }
+ 
  octave_value
  get_property_from_handle (double handle, const std::string &property,
  			  const std::string &func)
Index: scripts/plot/Makefile.in
===================================================================
RCS file: /cvs/octave/scripts/plot/Makefile.in,v
retrieving revision 1.66
diff -c -p -r1.66 Makefile.in
*** scripts/plot/Makefile.in	12 Jan 2008 08:00:38 -0000	1.66
--- scripts/plot/Makefile.in	22 Jan 2008 13:57:27 -0000
*************** SOURCES = \
*** 85,91 ****
    contourc.m \
    contourf.m \
    cylinder.m \
!   drawnow.m \
    ellipsoid.m \
    errorbar.m \
    ezcontourf.m \
--- 85,91 ----
    contourc.m \
    contourf.m \
    cylinder.m \
!   gnuplot_drawnow.m \
    ellipsoid.m \
    errorbar.m \
    ezcontourf.m \