## Copyright (C) 2005, 2006, 2007, 2008, 2009 John W. Eaton

##

## This file is part of Octave.

##

## Octave is free software; you can redistribute it and/or modify it

## under the terms of the GNU General Public License as published by

## the Free Software Foundation; either version 3 of the License, or (at

## your option) any later version.

##

## Octave is distributed in the hope that it will be useful, but

## WITHOUT ANY WARRANTY; without even the implied warranty of

## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

## General Public License for more details.

##

## You should have received a copy of the GNU General Public License

## along with Octave; see the file COPYING.  If not, see

## <http://www.gnu.org/licenses/>.

## -*- texinfo -*-

## @deftypefn {Function File} {} drawnow ()

## Update and display the current graphics.

##

## Octave automatically calls drawnow just before printing a prompt,

## when @code{sleep} or @code{pause} is called, or while waiting for

## command-line input.

## @end deftypefn

## Author: jwe

function gnuplot_drawnow (h, term, file, mono, debug_file)

  if (nargin < 4)

    mono = false;

  endif

  if (nargin >= 3 && nargin <= 5)

    ## Produce various output formats, or redirect gnuplot stream to a

    ## debug file.

    plot_stream = [];

    fid = [];

    printing = ! output_to_screen (gnuplot_trim_term (term));

    default_plot_stream = get (h, "__plot_stream__");

    unwind_protect

      plot_stream = __gnuplot_open_stream__ (2, h);

      if (__gnuplot_has_feature__ ("variable_GPVAL_TERMINALS"))

        available_terminals = __gnuplot_get_var__ (plot_stream, "GPVAL_TERMINALS");

        available_terminals = regexp (available_terminals, "\\b\\w+\\b", "match");

        gnuplot_supports_term = any (strcmpi (available_terminals,

                                              gnuplot_trim_term (term)));

      else

        gnuplot_supports_term = true;

      endif

      if (gnuplot_supports_term)

        [enhanced, implicit_margin] = gnuplot_set_term (plot_stream (1), true,

                                                        h, term, file);

        __go_draw_figure__ (h, plot_stream(1), enhanced, mono, printing, implicit_margin);

        if (nargin == 5)

          fid = fopen (debug_file, "wb");

          [enhanced, implicit_margin] = gnuplot_set_term (fid, true, h, term, file);

          __go_draw_figure__ (h, fid, enhanced, mono, printing, implicit_margin);

        endif

      else

        error ("gnuplot_drawnow: the gnuplot terminal, \"%s\", is not available.",

               gnuplot_trim_term (term))

      endif

    unwind_protect_cleanup

      set (h, "__plot_stream__", default_plot_stream);

      if (! isempty (plot_stream))

        pclose (plot_stream(1));

        if (numel (plot_stream) == 2)

          pclose (plot_stream(2));

        endif

      endif

      if (! isempty (fid))

        fclose (fid);

      endif

    end_unwind_protect

  elseif (nargin == 1)

    ##  Graphics terminal for display.

    plot_stream = get (h, "__plot_stream__");

    if (isempty (plot_stream))

      plot_stream = __gnuplot_open_stream__ (2, h);

      new_stream = true;

    else

      new_stream = false;

    endif

    enhanced = gnuplot_set_term (plot_stream (1), new_stream, h);

    __go_draw_figure__ (h, plot_stream (1), enhanced, mono, 0);

    fflush (plot_stream (1));

  else

    print_usage ();

  endif

endfunction

function implicit_margin = gnuplot_implicit_margin (term, opts_str)

  ## gnuplot has an implicit margin of 50pts for PS output.

  if (strcmpi (term, "postscript"))

    if (isempty (strfind (opts_str, " eps"))

        && isempty (strfind (opts_str, "eps ")))

      implicit_margin = 50/72;

    else

      ## When zero, the behavior of gnuplot changes.

      implicit_margin = 1/72;

    endif

  else

    implicit_margin = 0.0;

  endif

endfunction

function [enhanced, implicit_margin] = gnuplot_set_term (plot_stream, new_stream, h, term, file)

  ## Generate the gnuplot "set terminal <term> ..." command.

  ## When "term" originates from print.m, it may include other options.

  if (nargin < 4)

    ## This supports the gnuplot backend.

    term = gnuplot_default_term ();

    opts_str = "";

  else

    ## Get the one word terminal id and save the remaining as options to

    ## be passed on to gnuplot.  The terminal may respect the backend.

    [term, opts_str] = gnuplot_trim_term (term);

    if (strcmpi (term, "pdf") && strcmpi (opts_str, "color"))

      ## FIXME -- "color" for the pdf terminal produces a gnuplot error.

      opts_str = "";

    endif

  endif

  implicit_margin = gnuplot_implicit_margin (term, opts_str);

  enhanced = gnuplot_is_enhanced_term (term);

  ## Set the terminal.

  if (! isempty (term))

    if (enhanced)

      enh_str = "enhanced";

    else

      enh_str = "";

    endif

    if (! isempty (h) && isfigure (h))

      ## Generate gnuoplot title string for backend plot windows.

      if (output_to_screen (term))

        fig.numbertitle = get (h, "numbertitle");

        fig.name = get (h, "name");

        if (strcmpi (get (h, "numbertitle"), "on"))

          title_str = sprintf ("Figure %d", h);

        else

          title_str = "";

        endif

        if (! isempty (fig.name) && ! isempty (title_str))

          title_str = sprintf ("%s: %s", title_str, fig.name);

        elseif (! isempty (fig.name) && isempty (title_str))

          title_str = fig.name;

        endif

        if (! isempty (title_str))

          title_str = sprintf ("title \"%s\"", title_str);

        endif

      else

        title_str = "";

      endif

      if (! (any (strfind (opts_str, " size ") > 0) 

	  || any (strfind (opts_str, "size ") == 1)))

        ## Convert position to units used by gnuplot.

        if (output_to_screen (term))

          ## Get figure size in pixels.  Rely on listener

	  ## to handle coversion of position property.

	  units = get (h, "units");

	  unwind_protect

	    set (h, "units", "pixels");

	    position_in_pixesl = get (h, "position");

	  unwind_protect_cleanup

	    set (h, "units", units);

	  end_unwind_protect

	  gnuplot_pos = position_in_pixesl(1:2);

	  gnuplot_size = position_in_pixesl(3:4);

        else

          ## Get size of the printed plot in inches. Rely on listener

	  ## to handle coversion of papersize property.

	  paperunits = get (h, "paperunits");

	  unwind_protect

	    set (h, "paperunits", "inches");

            gnuplot_size = get (h, "papersize");

	  unwind_protect_cleanup

	    set (h, "paperunits", paperunits);

	  end_unwind_protect

          if (term_units_are_pixels (term))

	    ## Convert to inches using the property set by print().

	    gnuplot_size = gnuplot_size * get (h, "__pixels_per_inch__");

	  else

	    ## Implicit margins are in units of "inches"

	    gnuplot_size = gnuplot_size - implicit_margin;

          endif

        endif

	[begin_match, end_match, te, match] = regexp (opts_str, "(\\s-r\\d+)|(^-r\\d+)");

	if (! isempty (begin_match))

	  error ("gnuplot_drawnow.m: specifying resultion, '%s', not supported for terminal '%s'",

	         strtrim (match{1}), term)

	endif

        if (all (gnuplot_size > 0))

          ## Set terminal size.

          terminals_with_size = {"emf", "gif", "jpeg", "latex", "pbm", ...

                                 "pdf", "png", "postscript", "svg", ...

                                 "epslatex", "pstex", "pslatex"};

          if (__gnuplot_has_feature__ ("x11_figure_position"))

            terminals_with_size{end+1} = "x11";

          endif

          if (__gnuplot_has_feature__ ("wxt_figure_size"))

            terminals_with_size{end+1} = "wxt";

          endif

          if (any (strncmpi (term, terminals_with_size, 3)))

	    if (term_units_are_pixels (term))

              size_str = sprintf ("size %d,%d", gnuplot_size);

	    else

              size_str = sprintf ("size %.15g,%.15g", gnuplot_size);

	    endif

            if (strncmpi (term, "X11", 3) && __gnuplot_has_feature__ ("x11_figure_position"))

	      ## X11 allows the window to be positioned as well.

	      units = get (0, "units");

	      unwind_protect

	        set (0, "units", "pixels");

	        screen_size = get (0, "screensize")(3:4);

	      unwind_protect_cleanup

	        set (0, "units", units);

	      end_unwind_protect

              if (all (screen_size > 0))

                ## For X11, set the figure positon as well as the size

                ## gnuplot position is UL, Octave's is LL (same for screen/window)

                gnuplot_pos(2) = screen_size(2) - gnuplot_pos(2) - gnuplot_size(2);

                gnuplot_pos = max (gnuplot_pos, 1);

                size_str = sprintf ("%s position %d,%d", size_str, 

                                    gnuplot_pos(1), gnuplot_pos(2));

              endif

            endif

          elseif (strncmpi (term, "aqua", 3))

            ## Aqua has size, but the format is different.

            size_str = sprintf ("size %d %d", gnuplot_size);

          elseif (strncmpi (term, "fig", 3))

            ## Fig also has size, but the format is different.

            size_str = sprintf ("size %.15g %.15g", gnuplot_size);

          elseif (any (strncmpi (term, {"corel", "hpgl"}, 3)))

            ## The size for corel and hpgl are goes at the end (implicit).

            size_str = sprintf ("%.15g %.15g", gnuplot_size);

          elseif (any (strncmpi (term, {"dxf"}, 3)))

            ## DXF uses autocad units.

            size_str = "";

          else

            size_str = "";

          endif

        else

          size_str = "";

	  warning ("gnuplot_set_term: size is zero")

        endif

      else

        ## A specified size take priority over the figure properies.

        size_str = "";

      endif

    else

      if isempty (h)

        disp ("gnuplot_set_term: figure handle is empty")

      elseif !isfigure(h)

        disp ("gnuplot_set_term: not a figure handle")

      endif

      title_str = "";

      size_str = "";

    endif

    ## Set the gnuplot terminal (type, enhanced, title, options & size).

    term_str = sprintf ("set terminal %s", term);

    if (! isempty (enh_str))

      term_str = sprintf ("%s %s", term_str, enh_str);

    endif

    if (! isempty (title_str))

      term_str = sprintf ("%s %s", term_str, title_str);

    endif

    if (nargin > 3 && ischar (opts_str))

      ## Options must go last.

      term_str = sprintf ("%s %s", term_str, opts_str);

    endif

    if (! isempty (size_str) && new_stream)

      ## size_str comes after other options to permit specification of

      ## the canvas size for terminals cdr/corel.

      term_str = sprintf ("%s %s", term_str, size_str);

    endif

    ## Work around the gnuplot feature of growing the x11 window when

    ## the mouse and multiplot are set.

    fputs (plot_stream, "unset multiplot;\n");

    if (! strcmp (term, "x11")

        || numel (findall (h, "type", "axes")) > 1

        || numel (findall (h, "type", "image")) > 0)

      fprintf (plot_stream, "%s\n", term_str);

      if (nargin == 5)

        if (! isempty (file))

          fprintf (plot_stream, "set output '%s';\n", file);

        endif

      endif

      fputs (plot_stream, "set multiplot;\n");

    elseif (strcmp (term, "x11"))

      fprintf (plot_stream, "%s\n", term_str);

      if (nargin == 5)

        if (! isempty (file))

          fprintf (plot_stream, "set output '%s';\n", file);

        endif

      endif

    endif

  else

    ## gnuplot will pick up the GNUTERM environment variable itself

    ## so no need to set the terminal type if not also setting the

    ## figure title, enhanced mode, or position.

  endif

endfunction

function term = gnuplot_default_term ()

  term = getenv ("GNUTERM");

  ## If not specified, guess the terminal type.

  if (isempty (term))

    if (ismac ())

      term = "aqua";

    elseif (! isunix ())

      term = "windows";

    else

      term = "x11";

    endif

  endif

endfunction

function [term, opts] = gnuplot_trim_term (string)

  ## Extract the terminal type and terminal options (from print.m)

  string = deblank (string);

  n = strfind (string, ' ');

  if (isempty (n))

    term = string;

    opts = "";

  else

    term = string(1:(n-1));

    opts = string((n+1):end);

  endif

endfunction

function have_enhanced = gnuplot_is_enhanced_term (term)

  persistent enhanced_terminals;

  if (isempty (enhanced_terminals))

    ## Don't include pstex, pslatex or epslatex here as the TeX commands

    ## should not be interpreted in that case.

    enhanced_terminals = {"aqua", "dumb", "png", "jpeg", "gif", "pm", ...

                          "windows", "wxt", "svg", "postscript", "x11", "pdf"};

  endif

  if (nargin < 1)

    ## Determine the default gnuplot terminal.

    term = gnuplot_default_term ();

  endif

  have_enhanced = any (strncmp (enhanced_terminals, term, min (numel (term), 3)));

endfunction

function ret = output_to_screen (term)

  ret = any (strcmpi ({"aqua", "wxt", "x11", "windows", "pm"}, term));

endfunction

function ret = term_units_are_pixels (term)

  ret = any (strncmpi ({"emf", "gif", "jpeg", "pbm", "png", "svg"}, term, 3));

endfunction