## Copyright (C) 2005, 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} {} __go_draw_figure__ (@var{h}, @var{plot_stream}, @var{enhanced}, @var{mono})

## Undocumented internal function.

## @end deftypefn

## Author: jwe

function __go_draw_figure__ (h, plot_stream, enhanced, mono, output_to_paper, implicit_margin)

  if (nargin < 5)

    output_to_paper = false;

  elseif (nargin < 6)

    ## Gnuplot has implicit margins for some output. For example, for postscript

    ## the margin is 50pts. If not specified asssume 0.

    implicit_margin = 0;

  endif

  if (nargin >= 4 && nargin <= 6)

    htype = get (h, "type");

    if (strcmp (htype, "figure"))

      ## When printing, set paperunits to inches and rely on a listener to convert

      ## the values for papersize and paperposition.

      if (output_to_paper)

	orig_paper_units = get (h, "paperunits");

	gpval_term = __gnuplot_get_var__ (h, "GPVAL_TERM");

	gpval_termoptions = __gnuplot_get_var__ (h, "GPVAL_TERMOPTIONS");

	unwind_protect

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

          paper_size = get (h, "papersize");

          paper_position = get (h, "paperposition");

          paper_position = paper_position ./ paper_size([1, 2, 1, 2]);

	  implicit_margin = implicit_margin ./ paper_size;

	unwind_protect_cleanup

	  set (h, "paperunits", orig_paper_units);

	end_unwind_protect

	if (strcmp (gpval_term, "postscript")

	    && ! isempty (strfind (gpval_termoptions, "landscape")))

	  ## This needed to obtain the expected result.

	  implicit_margin(2) = -implicit_margin(2);

	endif

      else

	implicit_margin = implicit_margin * [1 1];

      endif

      ## Get complete list of children.

      kids = allchild (h);

      nkids = length (kids);

      if (nkids > 0)

	fputs (plot_stream, "\nreset;\n");

	fputs (plot_stream, "set autoscale keepfix;\n");

	fputs (plot_stream, "set origin 0, 0\n");

	fputs (plot_stream, "set size 1, 1\n");

	for i = 1:nkids

	  type = get (kids(i), "type");

	  switch (type)

	    case "axes"

	      ## Rely upon listener to convert axes position to "normalized" units.

	      orig_axes_units = get (kids(i), "units");

	      orig_axes_position = get (kids(i), "position");

	      unwind_protect

		set (kids(i), "units", "normalized");

		if (output_to_paper)

		  axes_position_on_page = orig_axes_position .* paper_position([3, 4, 3 ,4]);

		  axes_position_on_page(1:2) = axes_position_on_page(1:2) +  paper_position(1:2);

		  set (kids(i), "position", axes_position_on_page);

		  __go_draw_axes__ (kids(i), plot_stream, enhanced, mono, implicit_margin);

		else

		  ## Return axes "units" and "position" back to their original values.

		  __go_draw_axes__ (kids(i), plot_stream, enhanced, mono, implicit_margin);

		endif

		unwind_protect_cleanup

		set (kids(i), "units", orig_axes_units);

		set (kids(i), "position", orig_axes_position);

	      end_unwind_protect

	    otherwise

	      error ("__go_draw_figure__: unknown object class, %s", type);

	  endswitch

	endfor

      else

	fputs (plot_stream, "\nreset; clear;\n");

	fflush (plot_stream);

      endif

    else

      error ("__go_draw_figure__: expecting figure object, found `%s'",

	     htype);

    endif

  else

    print_usage ();

  endif    

endfunction