## Copyright (C) 2005, 2007 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_axes__ (@var{h}, @var{plot_stream}, @var{enhanced}, @var{mono})
## Undocumented internal function.
## @end deftypefn

## Author: jwe

function __go_draw_axes__ (h, plot_stream, enhanced, mono, implicit_margin)

  if (nargin >= 4 && nargin <= 5)

    showhiddenhandles = get (0, "showhiddenhandles");
    unwind_protect
      set (0, "showhiddenhandles", "on");
      axis_obj = __get__ (h);
    unwind_protect_cleanup
      set (0, "showhiddenhandles", showhiddenhandles);
    end_unwind_protect

    parent_figure_obj = get (axis_obj.parent);

    ## Set to false for plotyy axes.
    if (strcmp (axis_obj.tag, "plotyy"))
      ymirror = false;
    else
      ymirror = true;
    endif

    nd = __calc_dimensions__ (axis_obj);
    pos = axis_obj.position;
    pos = pos - implicit_margin([1, 2, 1, 2]).*[1, 1, -0.5, -0.5];
    if (__gnuplot_has_feature__ ("screen_coordinates_for_{lrtb}margin"))
      if (strcmpi (axis_obj.dataaspectratiomode, "manual"))
	pos = __actual_axis_position__ (axis_obj);
      endif
      if (nd == 2)
	x = [1, 1];
      else
	## 3D plots need to be sized down to fit in the window.
	x = 1.0 ./ sqrt([2, 2.5]);
      endif
      fprintf (plot_stream, "set tmargin screen %.15g;\n", pos(2)+pos(4)/2+x(2)*pos(4)/2);
      fprintf (plot_stream, "set bmargin screen %.15g;\n", pos(2)+pos(4)/2-x(2)*pos(4)/2);
      fprintf (plot_stream, "set lmargin screen %.15g;\n", pos(1)+pos(3)/2-x(1)*pos(3)/2);
      fprintf (plot_stream, "set rmargin screen %.15g;\n", pos(1)+pos(3)/2+x(1)*pos(3)/2);
    else
      ## FIXME -- nothing should change for gnuplot 4.2.x.
      fprintf (plot_stream, "set tmargin 0;\n");
      fprintf (plot_stream, "set bmargin 0;\n");
      fprintf (plot_stream, "set lmargin 0;\n");
      fprintf (plot_stream, "set rmargin 0;\n");

      fprintf (plot_stream, "set origin %.15g, %.15g;\n", pos(1), pos(2));
      fprintf (plot_stream, "set size %.15g, %.15g;\n", pos(3), pos(4));

      if (strcmpi (axis_obj.dataaspectratiomode, "manual"))
        r = axis_obj.dataaspectratio;
        fprintf (plot_stream, "set size ratio %.15g;\n", -r(2)/r(1));
      else
        fputs (plot_stream, "set size noratio;\n");
      endif
    endif

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

    if (! isempty (axis_obj.title))
      t = get (axis_obj.title);
      if (isempty (t.string))
	fputs (plot_stream, "unset title;\n");
      else
	[tt, f, s] = __maybe_munge_text__ (enhanced, t, "string");
	if (strcmp (f, "*"))
	  fontspec = "";
	else
	  fontspec = sprintf ("font \"%s,%d\"", f, s);
	endif
	fprintf (plot_stream, "set title \"%s\" %s %s;\n",
		 undo_string_escapes (tt), fontspec,
		 __do_enhanced_option__ (enhanced, t));
      endif
    endif

    if (! isempty (axis_obj.xlabel))
      t = get (axis_obj.xlabel);
      angle = t.rotation;
      colorspec = get_text_colorspec (axis_obj.xcolor, mono);
      if (isempty (t.string))
	fprintf (plot_stream, "unset xlabel;\n");
	fprintf (plot_stream, "unset x2label;\n");
      else
	[tt, f, s] = __maybe_munge_text__ (enhanced, t, "string");
	if (strcmp (f, "*"))
	  fontspec = "";
	else
	  fontspec = sprintf ("font \"%s,%d\"", f, s);
	endif
	if (strcmpi (axis_obj.xaxislocation, "top"))
	  fprintf (plot_stream, "set x2label \"%s\" %s %s %s",
		   undo_string_escapes (tt), colorspec, fontspec,
		   __do_enhanced_option__ (enhanced, t));
	else
	  fprintf (plot_stream, "set xlabel \"%s\" %s %s %s",
		   undo_string_escapes (tt), colorspec, fontspec,
		   __do_enhanced_option__ (enhanced, t));
	endif
	fprintf (plot_stream, " rotate by %f;\n", angle);
	if (strcmpi (axis_obj.xaxislocation, "top"))
	  fprintf (plot_stream, "unset xlabel;\n");
	else
	  fprintf (plot_stream, "unset x2label;\n");
	endif
      endif
    endif

    if (! isempty (axis_obj.ylabel))
      t = get (axis_obj.ylabel);
      angle = t.rotation;
      colorspec = get_text_colorspec (axis_obj.ycolor, mono);
      if (isempty (t.string))
	fprintf (plot_stream, "unset ylabel;\n");
	fprintf (plot_stream, "unset y2label;\n");
      else
	[tt, f, s] = __maybe_munge_text__ (enhanced, t, "string");
	if (strcmp (f, "*"))
	  fontspec = "";
	else
	  fontspec = sprintf ("font \"%s,%d\"", f, s);
	endif
	if (strcmpi (axis_obj.yaxislocation, "right"))
	  fprintf (plot_stream, "set y2label \"%s\" %s %s %s",
		   undo_string_escapes (tt), colorspec, fontspec,
		   __do_enhanced_option__ (enhanced, t));
	else
	  fprintf (plot_stream, "set ylabel \"%s\" %s %s %s",
		   undo_string_escapes (tt), colorspec, fontspec,
		   __do_enhanced_option__ (enhanced, t));
	endif
	fprintf (plot_stream, " rotate by %f;\n", angle);
	if (strcmpi (axis_obj.yaxislocation, "right"))
	  fprintf (plot_stream, "unset ylabel;\n");
	else
	  fprintf (plot_stream, "unset y2label;\n");
	endif
      endif
    endif

    if (! isempty (axis_obj.zlabel))
      t = get (axis_obj.zlabel);
      angle = t.rotation;
      colorspec = get_text_colorspec (axis_obj.zcolor, mono);
      if (isempty (t.string))
	fputs (plot_stream, "unset zlabel;\n");
      else
	[tt, f, s] = __maybe_munge_text__ (enhanced, t, "string");
	if (strcmp (f, "*"))
	  fontspec = "";
	else
	  fontspec = sprintf ("font \"%s,%d\"", f, s);
	endif
	fprintf (plot_stream, "set zlabel \"%s\" %s %s %s",
		 undo_string_escapes (tt), colorspec, fontspec,
		 __do_enhanced_option__ (enhanced, t));
	fprintf (plot_stream, " rotate by %f;\n", angle);
      endif
    endif

    if (strcmpi (axis_obj.xaxislocation, "top"))
      xaxisloc = "x2";
      xaxisloc_using = "x2";
    else
      xaxisloc = "x";
      xaxisloc_using = "x1";
      if (strcmpi (axis_obj.xaxislocation, "zero"))
	fputs (plot_stream, "set xzeroaxis;\n");
      endif
    endif
    if (strcmpi (axis_obj.yaxislocation, "right"))
      yaxisloc = "y2";
      yaxisloc_using = "y2";
    else
      yaxisloc = "y";
      yaxisloc_using = "y1";
      if (strcmpi (axis_obj.yaxislocation, "zero"))
	fputs (plot_stream, "set yzeroaxis;\n");
      endif
    endif

    have_grid = false;

    if (strcmpi (axis_obj.xgrid, "on"))
      have_grid = true;
      fprintf (plot_stream, "set grid %stics;\n", xaxisloc);
    else
      fprintf (plot_stream, "set grid no%stics;\n", xaxisloc);
    endif

    if (strcmpi (axis_obj.ygrid, "on"))
      have_grid = true;
      fprintf (plot_stream, "set grid %stics;\n", yaxisloc);
    else
      fprintf (plot_stream, "set grid no%stics;\n", yaxisloc);
    endif

    if (strcmpi (axis_obj.zgrid, "on"))
      have_grid = true;
      fputs (plot_stream, "set grid ztics;\n");
    else
      fputs (plot_stream, "set grid noztics;\n");
    endif

    if (strcmpi (axis_obj.xminorgrid, "on"))
      have_grid = true;
      fprintf (plot_stream, "set m%stics 5;\n", xaxisloc);
      fprintf (plot_stream, "set grid m%stics;\n", xaxisloc);
    else
      fprintf (plot_stream, "set grid nom%stics;\n", xaxisloc);
    endif

    if (strcmpi (axis_obj.yminorgrid, "on"))
      have_grid = true;
      fprintf (plot_stream, "set m%stics 5;\n", yaxisloc);
      fprintf (plot_stream, "set grid m%stics;\n", yaxisloc);
    else
      fprintf (plot_stream, "set grid nom%stics;\n", yaxisloc);
    endif

    if (strcmpi (axis_obj.zminorgrid, "on"))
      have_grid = true;
      fputs (plot_stream, "set mztics 5;\n");
      fputs (plot_stream, "set grid mztics;\n");
    else
      fputs (plot_stream, "set grid nomztics;\n");
    endif

    ## The grid front/back/layerdefault option also controls the
    ## appearance of tics, so it is used even if the grid is absent.
    if (strcmpi (axis_obj.layer, "top"))
      fputs (plot_stream, "set grid front;\n");
    else
      fputs (plot_stream, "set grid layerdefault;\n");
    endif
    if (! have_grid)
      fputs (plot_stream, "unset grid;\n");
    endif

    do_tics (axis_obj, plot_stream, ymirror, mono);

    xlogscale = strcmpi (axis_obj.xscale, "log");
    if (xlogscale)
      fprintf (plot_stream, "set logscale %s;\n", xaxisloc);
    else
      fprintf (plot_stream, "unset logscale %s;\n", xaxisloc);
    endif

    ylogscale = strcmpi (axis_obj.yscale, "log");
    if (ylogscale)
      fprintf (plot_stream, "set logscale %s;\n", yaxisloc);
    else
      fprintf (plot_stream, "unset logscale %s;\n", yaxisloc);
    endif

    zlogscale = strcmpi (axis_obj.zscale, "log");
    if (zlogscale)
      fputs (plot_stream, "set logscale z;\n");
    else
      fputs (plot_stream, "unset logscale z;\n");
    endif

    xautoscale = strcmpi (axis_obj.xlimmode, "auto");
    yautoscale = strcmpi (axis_obj.ylimmode, "auto");
    zautoscale = strcmpi (axis_obj.zlimmode, "auto");
    cautoscale = strcmpi (axis_obj.climmode, "auto");
    cdatadirect = false;
    truecolor = false;

    fputs (plot_stream, "set clip two;\n");

    kids = axis_obj.children;
    ## Remove the axis labels and title from the children, and
    ## preserved the original order.
    [jnk, k] = setdiff (kids, [axis_obj.xlabel; axis_obj.ylabel; ...
                               axis_obj.zlabel; axis_obj.title]);
    kids = kids (sort (k));

    if (nd == 3)
      fputs (plot_stream, "set parametric;\n");
      fputs (plot_stream, "set style data lines;\n");
      fputs (plot_stream, "set surface;\n");
      fputs (plot_stream, "unset contour;\n");
    endif

    data_idx = 0;
    data = cell ();
    is_image_data = [];
    hidden_removal = NaN;
    view_map = false;

    xlim = axis_obj.xlim;
    ylim = axis_obj.ylim;
    zlim = axis_obj.zlim;
    clim = axis_obj.clim;

    if (! cautoscale && clim(1) == clim(2))
      clim(2)++;
    endif

    [view_cmd, view_fcn, view_zoom] = image_viewer ();
    use_gnuplot_for_images = (ischar (view_fcn)
			      && strcmpi (view_fcn, "gnuplot_internal"));

    ximg_data = {};
    ximg_data_idx = 0;

    while (! isempty (kids))

      obj = get (kids(end));
      kids = kids(1:(end-1));

      if (strcmpi (obj.visible, "off"))
	continue;
      endif

      ## Check for facecolor interpolation for surfaces.
      doing_interp_color = ...
         isfield (obj, "facecolor") && strncmp (obj.facecolor, "interp", 6);

      switch (obj.type)
	case "image"
	  img_data = obj.cdata;
	  img_xdata = obj.xdata;
	  img_ydata = obj.ydata;

	  if (use_gnuplot_for_images)

	    if (ndims (img_data) == 3)
	      truecolor = true;
	    elseif (strcmpi (obj.cdatamapping, "direct"))
	      cdatadirect = true;
	    endif
	    fputs (plot_stream, "set border front;\n");
	    data_idx++;
	    is_image_data(data_idx) = true;
	    parametric(data_idx) = false;
	    have_cdata(data_idx) = false;

	    [y_dim, x_dim] = size (img_data(:,:,1));
	    if (x_dim > 1)
	      dx = abs (img_xdata(2)-img_xdata(1))/(x_dim-1);
	    else
	      x_dim = 2;
	      img_data = [img_data, img_data];
	      dx = abs (img_xdata(2)-img_xdata(1));
	    endif
	    if (y_dim > 1)
	      dy = abs (img_ydata(2)-img_ydata(1))/(y_dim-1);
	    else
	      y_dim = 2;
	      img_data = [img_data; img_data];
	      dy = abs (img_ydata(2)-img_ydata(1));
	    endif
	    x_origin = min (img_xdata);
	    y_origin = min (img_ydata);

	    if (ndims (img_data) == 3)
	      data{data_idx} = permute (img_data, [3, 1, 2])(:);
	      format = "1:2:3";
	      imagetype = "rgbimage";
	    else
	      data{data_idx} = img_data(:);
	      format = "1";
	      imagetype = "image";
	    endif

	    titlespec{data_idx} = "title \"\"";
	    usingclause{data_idx} = sprintf ("binary array=%dx%d scan=yx origin=(%.15g,%.15g) dx=%.15g dy=%.15g using %s",
		x_dim, y_dim, x_origin, y_origin, dx, dy, format);
	    withclause{data_idx} = sprintf ("with %s", imagetype);

	  else
	    ximg_data{++ximg_data_idx} = img_data;
	  endif

	case "line"
	  if (strncmp (obj.linestyle, "none", 4)
	      && (! isfield (obj, "marker")
		  || (isfield (obj, "marker")
		      && strncmp (obj.marker, "none", 4))))
	    continue;
	  endif
	  data_idx++;
	  is_image_data(data_idx) = false;
	  parametric(data_idx) = true;
	  have_cdata(data_idx) = false;
	  if (isempty (obj.keylabel))
	    titlespec{data_idx} = "title \"\"";
	  else
	    tmp = undo_string_escapes (__maybe_munge_text__ (enhanced, obj, "keylabel"));
	    titlespec{data_idx} = cstrcat ("title \"", tmp, "\"");
	  endif
	  usingclause{data_idx} = sprintf ("record=%d", numel (obj.xdata));
	  errbars = "";
	  if (nd == 3)
	    xdat = obj.xdata(:);
	    ydat = obj.ydata(:);
	    if (! isempty (obj.zdata))
	      zdat = obj.zdata(:);
	    else
	      zdat = zeros (size (xdat));
	    endif
	    data{data_idx} = [xdat, ydat, zdat]';
	    usingclause{data_idx} = sprintf ("record=%d using ($1):($2):($3)", numel (xdat));
	    ## fputs (plot_stream, "set parametric;\n");
	  else
	    xdat = obj.xdata(:);
	    ydat = obj.ydata(:);
	    ldat = obj.ldata;
	    yerr = xerr = false;
	    if (! isempty (ldat))
	      yerr = true;
	      ldat = ldat(:);
	    endif
	    udat = obj.udata;
	    if (! isempty (udat))
	      udat = udat(:);
	    endif
	    xldat = obj.xldata;
	    if (! isempty (xldat))
	      xerr = true;
	      xldat = xldat(:);
	    endif
	    xudat = obj.xudata;
	    if (! isempty (xudat))
	      xudat = xudat(:);
	    endif
	    if (yerr)
	      if (isempty (ldat))
		ylo = ydat;
	      else
		ylo = ydat-ldat;
	      endif
	      if (isempty (udat))
		yhi = ydat;
	      else
		yhi = ydat+udat;
	      endif
	      if (xerr)
		if (isempty (xldat))
		  xlo = xdat;
		else
		  xlo = xdat-xldat;
		endif
		if (isempty (xudat))
		  xhi = xdat;
		else
		  xhi = xdat+xudat;
		endif
		data{data_idx} = [xdat, ydat, xlo, xhi, ylo, yhi]';
		usingclause{data_idx} = sprintf ("record=%d using ($1):($2):($3):($4):($5):($6)", numel (xdat));
		errbars = "xyerrorbars";
	      else
		data{data_idx} = [xdat, ydat, ylo, yhi]';
		usingclause{data_idx} = sprintf ("record=%d using ($1):($2):($3):($4)", numel (xdat));
		errbars = "yerrorbars";
	      endif
	    elseif (xerr)
	      if (isempty (xldat))
		xlo = xdat;
	      else
		xlo = xdat-xldat;
	      endif
	      if (isempty (xudat))
		xhi = xdat;
	      else
		xhi = xdat+xudat;
	      endif
	      data{data_idx} = [xdat, ydat, xlo, xhi]';
	      usingclause{data_idx} = sprintf ("record=%d using ($1):($2):($3):($4)", numel (xdat));
	      errbars = "xerrorbars";
	    else
	      data{data_idx} = [xdat, ydat]';
	      usingclause{data_idx} = sprintf ("record=%d using ($1):($2) axes %s%s",
					      rows(xdat), xaxisloc_using, yaxisloc_using);
	    endif
	  endif

	  [style, typ, with] = do_linestyle_command (obj, data_idx, mono,
						     plot_stream, errbars);

	  withclause{data_idx} = sprintf ("with %s linestyle %d",
					  style, data_idx);

       case "patch"
         cmap = parent_figure_obj.colormap;
	 [nr, nc] = size (obj.xdata);

	 if (! isempty (obj.cdata))
	   cdat = obj.cdata;
	   if (strcmpi (obj.cdatamapping, "direct"))
	     cdatadirect = true;
	   endif
	 else
	   cdat = [];
	 endif

	 for i = 1:nc
	   xcol = obj.xdata(:,i);
	   ycol = obj.ydata(:,i);
	   if (nd == 3)
	     if (! isempty (obj.zdata))
	       zcol = obj.zdata(:,i);
	     else
	       zcol = zeros (size (xcol));
	     endif
	   endif

	   if (! isnan (xcol) && ! isnan (ycol))
	     ## Is the patch closed or not
	     if (strncmp (obj.facecolor, "none", 4)) 
	       hidden_removal = false;
	     else
	       if (isnan (hidden_removal))
		 hidden_removal = true;
	       endif
	       if (nd == 3)
		 error ("gnuplot (as of v4.2) only supports 2D filled patches");
	       endif

	       data_idx++;
	       is_image_data(data_idx) = false;
	       parametric(data_idx) = false;
	       have_cdata(data_idx) = false;
	       if (i > 1 || isempty (obj.keylabel))
		 titlespec{data_idx} = "title \"\"";
	       else
		 tmp = undo_string_escapes (__maybe_munge_text__ (enhanced, obj, "keylabel"));
		 titlespec{data_idx} = cstrcat ("title \"", tmp, "\"");
	       endif
               if (isfield (obj, "facecolor"))
		 if ((strncmp (obj.facecolor, "flat", 4)
		     || strncmp (obj.facecolor, "interp", 6))
		     && isfield (obj, "cdata"))
		   if (ndims (obj.cdata) == 2
		       && (size (obj.cdata, 2) == nc
			   && (size (obj.cdata, 1) == 1
			       || size (obj.cdata, 1) == 3)))
		     ccol = cdat (:, i);
		   elseif (ndims (obj.cdata) == 2
		       && (size (obj.cdata, 1) == nc
			   && (size (obj.cdata, 2) == 1
			       || size (obj.cdata, 2) == 3)))
		     ccol = cdat (i, :);
		   elseif (ndims (obj.cdata) == 3)
		     ccol = permute (cdat (:, i, :), [1, 3, 2]);
		   else
		     ccol = cdat;
		   endif
		   if (strncmp (obj.facecolor, "flat", 4))
		     if (numel(ccol) == 3)
		       color = ccol;
		     else
		       r = 1 + round ((size (cmap, 1) - 1)
				      * (ccol - clim(1))/(clim(2) - clim(1)));
		       r = max (1, min (r, size (cmap, 1)));
		       color = cmap(r, :);
		     endif
		   elseif (strncmp (obj.facecolor, "interp", 6))
		     warning ("\"interp\" not supported, using 1st entry of cdata");
		     r = 1 + round ((size (cmap, 1) - 1) * ccol(1));
		     r = max (1, min (r, size (cmap, 1)));
		     color = cmap(r,:);
		   endif
		 elseif (isnumeric (obj.facecolor))
		   color = obj.facecolor;
		 else
		   color = [0, 1, 0];
		 endif
               else
		 color = [0, 1, 0];
               endif

	       if (mono)
		 colorspec = "";
               elseif (__gnuplot_has_feature__ ("transparent_patches")
		       && isscalar (obj.facealpha))
                 colorspec = sprintf ("lc rgb \"#%02x%02x%02x\" fillstyle transparent solid %f",
				      round (255*color), obj.facealpha);
	       else
		 colorspec = sprintf ("lc rgb \"#%02x%02x%02x\"",
				      round (255*color));
	       endif
	       withclause{data_idx} = sprintf ("with filledcurve %s",
					       colorspec);
	       data{data_idx} = [xcol, ycol]';
	       usingclause{data_idx} = sprintf ("record=%d using ($1):($2)",
						numel (xcol));
	     endif
	   endif

           ## patch outline
	   if (! strncmp (obj.edgecolor, "none", 4))

	     data_idx++;
             is_image_data(data_idx) = false;
             parametric(data_idx) = false;
	     have_cdata(data_idx) = false;
             titlespec{data_idx} = "title \"\"";
	     usingclause{data_idx} = sprintf ("record=%d", numel (obj.xdata));

	     if (isfield (obj, "markersize"))
	       mdat = obj.markersize / 3;
	     endif

             if (isfield (obj, "edgecolor"))
	       if ((strncmp (obj.edgecolor, "flat", 4)
		    || strncmp (obj.edgecolor, "interp", 6))
		   && isfield (obj, "cdata"))
		 if (ndims (obj.cdata) == 2
		     && (size (obj.cdata, 2) == nc
			 && (size (obj.cdata, 1) == 1
			     || size (obj.cdata, 1) == 3)))
		   ccol = cdat (:, i);
		 elseif (ndims (obj.cdata) == 2
			 && (size (obj.cdata, 1) == nc
			     && (size (obj.cdata, 2) == 1
				 || size (obj.cdata, 2) == 3)))
		   ccol = cdat (i, :);
		 elseif (ndims (obj.cdata) == 3)
		   ccol = permute (cdat (:, i, :), [1, 3, 2]);
		 else
		   ccol = cdat;
		 endif
		 if (strncmp (obj.edgecolor, "flat", 4))
		   if (numel(ccol) == 3)
		     color = ccol;
		   else
		     r = 1 + round ((size (cmap, 1) - 1)
				    * (ccol - clim(1))/(clim(2) - clim(1)));
		     r = max (1, min (r, size (cmap, 1)));
		     color = cmap(r, :);
		   endif
		 elseif (strncmp (obj.edgecolor, "interp", 6))
		   warning ("\"interp\" not supported, using 1st entry of cdata");
		   r = 1 + round ((size (cmap, 1) - 1) * ccol(1));
		   r = max (1, min (r, size (cmap, 1)));
		   color = cmap(r,:);
		 endif
	       elseif (isnumeric (obj.edgecolor))
		 color = obj.edgecolor;
	       else
		 color = [0, 0, 0];
	       endif
             else
	       color = [0, 0, 0];
             endif

	     if (isfield (obj, "linestyle"))
	       switch (obj.linestyle)
		 case "-"
		   lt = "lt 1";
		 case "--"
		   lt = "lt 2";
		 case ":"
		   lt = "lt 3";
		 case "-."
		   lt = "lt 6";
		 case "none"
		   lt = "";
		 otherwise
		   lt = "";
	       endswitch
	     else
	       lt = "";
	     endif

	     if (isfield (obj, "linewidth"))
	       lw = sprintf("linewidth %f", obj.linewidth);
	     else
	       lw  = "";
	     endif

	     if (isfield (obj, "marker"))
	       if (isfield (obj, "marker"))
		 switch (obj.marker)
		   case "+"
		     pt = "pt 1";
		   case "o"
		     pt = "pt 6";
		   case "*"
		     pt = "pt 3";
		   case "."
		     pt = "pt 0";
		   case "x"
		     pt = "pt 2";
		   case {"square", "s"}
		     pt = "pt 5";
		   case {"diamond", "d"}
		     pt = "pt 13";
		   case "^"
		     pt = "pt 9";
		   case "v"
		     pt = "pt 11";
		   case ">"
		     pt = "pt 8";
		   case "<"
		     pt = "pt 10";
		   case {"pentagram", "p"}
		     pt = "pt 4";
		   case {"hexagram", "h"}
		     pt = "pt 12";
		   case "none"
		     pt = "";
		   otherwise
		     pt = "";
		 endswitch
	       endif
	     else
	       pt = "";
	     endif

	     style = "lines";
	     if (isempty (lt))
	       if (! isempty (pt))
		 style = "points";
	       endif
	     elseif (! isempty (pt))
	       style = "linespoints";
	     endif

	     if (isfield (obj, "markersize"))
	       if (length (mdat) == nc)
		 m = mdat(i);
	       else
		 m = mdat;
	       endif
	       if (! strcmpi (style, "lines"))
		 ps = sprintf("pointsize %f", m);
	       else
		 ps = "";
	       endif
	     else
	       ps = "";
	     endif

	     if (mono)
	       colorspec = "";
	     else
	       colorspec = sprintf ("lc rgb \"#%02x%02x%02x\"",
				    round (255*color));
	     endif
	     withclause{data_idx} = sprintf ("with %s %s %s %s %s %s",
					     style, lw, pt, lt, ps, 
					     colorspec);

	     if (nd == 3)
	       if (! isnan (xcol) && ! isnan (ycol) && ! isnan (zcol))
		 data{data_idx} = [[xcol; xcol(1)], [ycol; ycol(1)], ...
				   [zcol; zcol(1)]]';
	       else
		 data{data_idx} = [xcol, ycol, zcol]';
	       endif
	       usingclause{data_idx} = sprintf ("record=%d using ($1):($2):($3)", columns (data{data_idx}));
	     else
	       if (! isnan (xcol) && ! isnan (ycol))
		 data{data_idx} = [[xcol; xcol(1)], [ycol; ycol(1)]]';
	       else
		 data{data_idx} = [xcol, ycol]';
	       endif
	       usingclause{data_idx} = sprintf ("record=%d using ($1):($2)", columns (data{data_idx}));
	     endif
	   endif
	 endfor

	case "surface"
	  view_map = true;
          if (! (strncmp (obj.edgecolor, "none", 4)
		 && strncmp (obj.facecolor, "none", 4)))
	    data_idx++;
	    is_image_data(data_idx) = false;
	    parametric(data_idx) = false;
	    have_cdata(data_idx) = true;
	    [style, typ, with] = do_linestyle_command (obj, data_idx,
						       mono, plot_stream);
	    if (isempty (obj.keylabel))
	      titlespec{data_idx} = "title \"\"";
	    else
	      tmp = undo_string_escapes (__maybe_munge_text__ (enhanced, obj, "keylabel"));
	      titlespec{data_idx} = cstrcat ("title \"", tmp, "\"");
	    endif
	    withclause{data_idx} = sprintf ("with pm3d linestyle %d",
		           		    data_idx);

	    xdat = obj.xdata;
	    ydat = obj.ydata;
	    zdat = obj.zdata;
	    cdat = obj.cdata;

  	    err = false;
            if (! size_equal(zdat, cdat))
              err = true;
            endif
	    if (isvector (xdat) && isvector (ydat) && ismatrix (zdat))
	      if (rows (zdat) == length (ydat)
		  && columns (zdat) == length (xdat))
                [xdat, ydat] = meshgrid (xdat, ydat);
	      else
                err = true;
	      endif
	    elseif (ismatrix (xdat) && ismatrix (ydat) && ismatrix (zdat))
	      if (! size_equal (xdat, ydat, zdat))
                err = true;
	      endif
	    else
	      err = true;
	    endif
	    if (err)
	      error ("__go_draw_axes__: invalid grid data");
	    endif
	    xlen = columns (zdat);
	    ylen = rows (zdat);
	    if (xlen == columns (xdat) && xlen == columns (ydat)
	        && ylen == rows (xdat) && ylen == rows (ydat))
	      len = 4 * xlen;
	      zz = zeros (ylen, len);
	      k = 1;
	      for kk = 1:4:len
	        zz(:,kk)   = xdat(:,k);
	        zz(:,kk+1) = ydat(:,k);
	        zz(:,kk+2) = zdat(:,k);
	        zz(:,kk+3) = cdat(:,k);
	        k++;
	      endfor
	      data{data_idx} = zz.';
	    endif

	    if (doing_interp_color)
	      interp_str = "interpolate 0, 0";
	    else
	      ## No interpolation of facecolors.
	      interp_str = "";
	    endif
	    usingclause{data_idx} = sprintf ("record=%dx%d using ($1):($2):($3):($4)", ylen, xlen);

            flat_interp_face = (strncmp (obj.facecolor, "flat", 4)
				|| strncmp (obj.facecolor, "interp", 6));
            flat_interp_edge = (strncmp (obj.edgecolor, "flat", 4)
				|| strncmp (obj.edgecolor, "interp", 6));

	    facecolor_none_or_white = (strncmp (obj.facecolor, "none", 4)
				       || (isnumeric (obj.facecolor)
					   && all (obj.facecolor == 1)));
	    hidden_removal = false;
            fputs (plot_stream, "set style increment default;\n");
            if (flat_interp_edge && facecolor_none_or_white)
	      withclause{data_idx} = "with line palette";
	      fputs (plot_stream, "unset pm3d\n");
	      if (all (obj.facecolor == 1))
                hidden_removal = true;
              endif
	    elseif (facecolor_none_or_white)
	      edgecol = obj.edgecolor;
	      if (mono)
		colorspec = "";
	      else
		colorspec = sprintf ("linecolor rgb \"#%02x%02x%02x\"",
				     round (255*edgecol));
	      endif
	      if (all (obj.facecolor == 1))
                hidden_removal = true;
              endif
	      fputs(plot_stream,"unset pm3d;\n");
              fprintf (plot_stream,
                       "set style line %d %s lw %f;\n",
                       data_idx, colorspec, obj.linewidth);
	      fputs(plot_stream,"set style increment user;\n");
	      withclause{data_idx} = sprintf("with line linestyle %d", data_idx);
	      fputs (plot_stream, "unset pm3d\n");
            endif

	    if (doing_interp_color)
	      ## "depthorder" interferes with interpolation of colors.
	      dord = "scansautomatic";
	    else
	      dord = "depthorder";
	    endif

	    if (flat_interp_face && strncmp (obj.edgecolor, "flat", 4))
              fprintf (plot_stream, "set pm3d explicit at s %s %s corners2color c3;\n", 
		       interp_str, dord);
            elseif (!facecolor_none_or_white)
              if (strncmp (obj.edgecolor, "none", 4))
                if (__gnuplot_has_feature__ ("transparent_surface") 
                    && isscalar (obj.facealpha))
                  fprintf (plot_stream,
                           "set style fill transparent solid %f;\n",
                           obj.facealpha);
                endif
                fprintf (plot_stream, "set pm3d explicit at s %s corners2color c3;\n", 
			 interp_str, dord);
              else
                edgecol = obj.edgecolor;
                if (ischar (obj.edgecolor))
                  edgecol = [0, 0, 0];
                endif
                fprintf (plot_stream, "set pm3d explicit at s hidden3d %d %s %s corners2color c3;\n", 
			 data_idx, interp_str, dord);

		if (mono)
		  colorspec = "";
		else
		  colorspec = sprintf ("linecolor rgb \"#%02x%02x%02x\"",
				       round (255*edgecol));
		endif
                fprintf (plot_stream,
                         "set style line %d %s lw %f;\n",
                         data_idx, colorspec, obj.linewidth);
                if (__gnuplot_has_feature__ ("transparent_surface") 
                    && isscalar (obj.facealpha))
                  fprintf (plot_stream,
                           "set style fill transparent solid %f;\n",
                           obj.facealpha);
                endif
              endif
            endif
	  endif

	case "text"
	  [label, f, s] = __maybe_munge_text__ (enhanced, obj, "string");
	  if (strcmp (f, "*"))
	    fontspec = "";
	  else
	    fontspec = sprintf ("font \"%s,%d\"", f, s);
	  endif
	  lpos = obj.position;
	  halign = obj.horizontalalignment;
	  angle = obj.rotation;
          units = obj.units;
	  color = obj.color;
          if (strcmpi (units, "normalized"))
            units = "graph";
          else
            units = "";
          endif
	  
	  if (isnumeric (color))
	    colorspec = get_text_colorspec (color, mono);
	  endif

	  if (nd == 3)
	    fprintf (plot_stream,
		     "set label \"%s\" at %s %.15g,%.15g,%.15g %s rotate by %f %s %s front %s;\n",
		     undo_string_escapes (label), units, lpos(1),
		     lpos(2), lpos(3), halign, angle, fontspec,
		     __do_enhanced_option__ (enhanced, obj), colorspec);
	  else
 	    fprintf (plot_stream,
 		     "set label \"%s\" at %s %.15g,%.15g %s rotate by %f %s %s front %s;\n",
 		     undo_string_escapes (label), units,
 		     lpos(1), lpos(2), halign, angle, fontspec,
		     __do_enhanced_option__ (enhanced, obj), colorspec);
	  endif

        case "hggroup"
	  ## Push group children into the kid list.
	  if (isempty (kids))
	    kids = obj.children;
	  elseif (! isempty (obj.children))
	    kids = [obj.children; kids];
	  endif

	otherwise
	  error ("__go_draw_axes__: unknown object class, %s",
		 obj.type);
      endswitch

    endwhile

    ## This is need to prevent warnings for rotations in 3D plots, while
    ## allowing colorbars with contours.
    if (nd == 2 || (data_idx > 1 && !view_map))
      fputs (plot_stream, "set pm3d implicit;\n");
    else
      fputs (plot_stream, "set pm3d explicit;\n");
    endif

    if (isnan(hidden_removal) || hidden_removal)
      fputs (plot_stream, "set hidden3d;\n");
    else
      fputs (plot_stream, "unset hidden3d;\n");
    endif

    have_data = (! (isempty (data) || all (cellfun (@isempty, data))));

    ## Note we don't use the [xy]2range of gnuplot as we don't use the
    ## dual axis plotting features of gnuplot.
    if (isempty (xlim))
      return;
    endif
    if (strcmpi (axis_obj.xdir, "reverse"))
      xdir = "reverse";
    else
      xdir = "noreverse";
    endif
    fprintf (plot_stream, "set xrange [%.15e:%.15e] %s;\n", xlim, xdir);

    if (isempty (ylim))
      return;
    endif
    if (strcmpi (axis_obj.ydir, "reverse"))
      ydir = "reverse";
    else
      ydir = "noreverse";
    endif
    fprintf (plot_stream, "set yrange [%.15e:%.15e] %s;\n", ylim, ydir);

    if (nd == 3)
      if (isempty (zlim))
	return;
      endif
      if (strcmpi (axis_obj.zdir, "reverse"))
	zdir = "reverse";
      else
	zdir = "noreverse";
      endif
      fprintf (plot_stream, "set zrange [%.15e:%.15e] %s;\n", zlim, zdir);
    endif

    cmap = parent_figure_obj.colormap;    
    cmap_sz = rows(cmap);

    if (! any (isinf (clim)))
      if (truecolor || ! cdatadirect)
	fprintf (plot_stream, "set cbrange [%g:%g];\n", clim);
      else
	fprintf (plot_stream, "set cbrange [1:%d];\n", cmap_sz);
      endif
    endif

    if (strcmpi (axis_obj.box, "on"))
      if (nd == 3)
	fputs (plot_stream, "set border 4095;\n");
      else
	fputs (plot_stream, "set border 431;\n");
      endif
    else
      if (nd == 3)
	fputs (plot_stream, "set border 895;\n");
      else
	if (strcmpi (axis_obj.yaxislocation, "right"))
	  fprintf (plot_stream, "unset ytics; set y2tics %s nomirror\n",
		   axis_obj.tickdir);
	  if (strcmpi (axis_obj.xaxislocation, "top"))
	    fprintf (plot_stream, "unset xtics; set x2tics %s nomirror\n",
		     axis_obj.tickdir);
	    fputs (plot_stream, "set border 12;\n");
	  else
	    fprintf (plot_stream, "unset x2tics; set xtics %s nomirror\n",
		     axis_obj.tickdir);
	    fputs (plot_stream, "set border 9;\n");
	  endif
	else
	  fprintf (plot_stream, "unset y2tics; set ytics %s nomirror\n",
		   axis_obj.tickdir);
	  if (strcmpi (axis_obj.xaxislocation, "top"))
	    fprintf (plot_stream, "unset xtics; set x2tics %s nomirror\n",
		     axis_obj.tickdir);
	    fputs (plot_stream, "set border 6;\n");
	  else
	    fprintf (plot_stream, "unset x2tics; set xtics %s nomirror\n",
		     axis_obj.tickdir);
	    fputs (plot_stream, "set border 3;\n");
	  endif
	endif
      endif
    endif

    if (strcmpi (axis_obj.visible, "off"))
      fputs (plot_stream, "unset border; unset tics\n");
    else
      fprintf (plot_stream, "set border lw %f;\n", axis_obj.linewidth);
    endif

    if (strcmpi (axis_obj.key, "on"))
      if (strcmpi (axis_obj.keybox, "on"))
	box = "box";
      else
	box = "nobox";
      endif
      if (strcmpi (axis_obj.keyreverse, "on"))
	reverse = "reverse";
      else
	reverse = "noreverse";
      endif
      inout = "inside";
      keypos = axis_obj.keypos;
      if (ischar (keypos))
	keypos = lower (keypos);
	keyout = findstr (keypos, "outside");
	if (! isempty (keyout))
	  inout = "outside";
	  keypos = keypos(1:keyout-1);
	endif
      endif
      switch (keypos)
	case -1
	  pos = "right top";
	  inout = "outside";
	case 1
	  pos = "right top";
	case 2
	  pos = "left top";
	case 3
	  pos = "left bottom";
	case {4, 0}
	  pos = "right bottom";
	case "north"
	  pos = "center top";
	case "south"
	  pos = "center bottom";
	case "east"
	  pos = "right center";
	case "west"
	  pos = "left center";
	case "northeast"
	  pos = "right top";
	case "northwest"
	  pos = "left top";
	case "southeast"
	  pos = "right bottom";
	case "southwest"
	  pos = "left bottom";
	case "best" 
	  pos = "";
	  warning ("legend: 'Best' not yet implemented for location specifier.\n");
	  ## Least conflict with data in plot.
	  ## Least unused space outside plot.
	otherwise
	  pos = "";
      endswitch
      fprintf (plot_stream, "set key %s %s %s %s;\n", inout, pos, box, reverse);
    else
      fputs (plot_stream, "unset key;\n");
    endif

    fputs (plot_stream, "set style data lines;\n");

    if (! use_gnuplot_for_images)
      for i = 1:ximg_data_idx
	view_fcn (xlim, ylim, ximg_data{i}, view_zoom, view_cmd);
      endfor
    endif

    if (length(cmap) > 0)
      fprintf (plot_stream,
	       "set palette positive color model RGB maxcolors %i;\n",
	       cmap_sz);
      fprintf (plot_stream,
	       "set palette file \"-\" binary record=%d using 1:2:3:4;\n",
	       cmap_sz);
      fwrite (plot_stream, [1:cmap_sz; cmap.'], "float32");
      fwrite (plot_stream, "\n");
    endif

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

    if (have_data)
      if (nd == 2)
	plot_cmd = "plot";
      else
	plot_cmd = "splot";
	rot_x = 90 - axis_obj.view(2);
	rot_z = axis_obj.view(1);
	while (rot_z < 0)
	  rot_z += 360;
	endwhile
 	fputs (plot_stream, "set ticslevel 0;\n");
	if (view_map && rot_x == 0 && rot_z == 0)
	  fputs (plot_stream, "set view map;\n");
	else
	  fprintf (plot_stream, "set view %.15g, %.15g;\n", rot_x, rot_z);
	endif
      endif
      if (is_image_data (1))
	fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", plot_cmd,
		 usingclause{1}, titlespec{1}, withclause{1});
      else
	fprintf (plot_stream, "%s \"-\" binary format='%%float64' %s %s %s \\\n", plot_cmd,
		 usingclause{1}, titlespec{1}, withclause{1});
      endif
      for i = 2:data_idx
	if (is_image_data (i))
	  fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", plot_cmd,
		   usingclause{i}, titlespec{i}, withclause{i});
	else
	  fprintf (plot_stream, ", \"-\" binary format='%%float64' %s %s %s \\\n",
		   usingclause{i}, titlespec{i}, withclause{i});
	endif
      endfor
      fputs (plot_stream, ";\n");
      for i = 1:data_idx
	if (is_image_data(i))
	  fwrite (plot_stream, data{i}, "float32");
	else
	  __gnuplot_write_data__ (plot_stream, data{i}, nd, parametric(i), 
				  have_cdata(i));
	endif
      endfor
    else
      fputs (plot_stream, "plot \"-\";\nInf Inf\ne\n");
    endif

    ## Needed to allow mouse rotation with pcolor.
    if (view_map)
      fputs (plot_stream, "unset view;\n");
    endif

    fflush (plot_stream);

  else
    print_usage ();
  endif

endfunction

function [style, typ, with] = do_linestyle_command (obj, idx, mono,
						    plot_stream, errbars = "")

  fprintf (plot_stream, "set style line %d default;\n", idx);
  fprintf (plot_stream, "set style line %d", idx);

  found_style = false;
  typ = NaN;
  with = "";

  if (isfield (obj, "color"))
    color = obj.color;
    if (isnumeric (color))
      if (! mono)
	fprintf (plot_stream, " linecolor rgb \"#%02x%02x%02x\"",
		 round (255*color));
      endif
    endif
    found_style = true;
  endif

  if (isfield (obj, "linestyle"))
    switch (obj.linestyle)
      case "-"
	lt = "1";
      case "--"
	lt = "2";
      case ":"
	lt = "3";
      case "-."
	lt = "6";
      case "none"
	lt = "";
      otherwise
	lt = "";
    endswitch

    ## FIXME -- linetype is currently broken, since it disables the
    ## gnuplot default dashed and solid linestyles with the only
    ## benefit of being able to specify '--' and get a single sized
    ## dashed line of identical dash pattern for all called this way.
    ## All dash patterns are a subset of "with lines" and none of the
    ## lt specifications will correctly propagate into the x11 terminal
    ## or the print command.   Therefore, it is currently disabled in
    ## order to allow print (..., "-dashed") etc. to work correctly.

    ##    if (! isempty (lt))
    ##      fprintf (plot_stream, " linetype %s", lt);
    ##      found_style = true;
    ##    endif

  else
    lt = "";
  endif

  if (isfield (obj, "linewidth"))
    fprintf (plot_stream, " linewidth %f", obj.linewidth);
    found_style = true;
  endif

  if (isfield (obj, "marker"))
    switch (obj.marker)
      case "+"
	pt = "1";
      case "o"
	pt = "6";
      case "*"
	pt = "3";
      case "."
	pt = "0";
      case "x"
	pt = "2";
      case {"square", "s"}
	pt = "5";
      case {"diamond", "d"}
	pt = "13";
      case "^"
	pt = "9";
      case "v"
	pt = "11";
      case ">"
	pt = "8";
      case "<"
	pt = "10";
      case {"pentagram", "p"}
	pt = "4";
      case {"hexagram", "h"}
	pt = "12";
      case "none"
	pt = "";
      otherwise
	pt = "";
    endswitch
    if (! isempty (pt))
      fprintf (plot_stream, " pointtype %s", pt);
      found_style = true;
    endif
  else
    pt = "";
  endif

  if (isempty (errbars))
    style = "lines";
    if (isempty (lt))
      if (! isempty (pt))
	style = "points";
      endif
    elseif (! isempty (pt))
      style = "linespoints";
    endif

    if (isfield (obj, "markersize"))
      fprintf (plot_stream, " pointsize %f", obj.markersize / 3);
      found_style = true;
    endif
  else
    style = errbars;
    found_style = true;
  endif

  if (! found_style)
    fputs (plot_stream, " default");
  endif

  fputs (plot_stream, ";\n");

endfunction

function nd = __calc_dimensions__ (obj)
  kids = obj.children;
  nd = 2;
  for i = 1:length (kids)
    obj = get (kids(i));
    switch (obj.type)
      case {"image", "text"}
	## ignore as they 
      case {"line", "patch"}
	if (! isempty (obj.zdata))
	  nd = 3;
	endif
      case "surface"
	nd = 3;
      case "hggroup"
        obj_nd = __calc_dimensions__ (obj);
        if (obj_nd == 3)
          nd = 3;
        endif
    endswitch
  endfor
endfunction

function __gnuplot_write_data__ (plot_stream, data, nd, parametric, cdata)
  
  ## DATA is already transposed.

  ## FIXME -- this may need to be converted to C++ for speed.

  ## Convert NA elements to normal NaN values because fprintf writes
  ## "NA" and that confuses gnuplot.
  idx = find (isna (data));
  if (any (idx))
    data(idx) = NaN;
  endif

  if (nd == 2)
    fwrite (plot_stream, data, "float64");
  elseif (nd == 3)
    if (parametric)
      fwrite (plot_stream, data, "float64");
    else
      nr = rows (data);
      if (cdata)
	for j = 1:4:nr
	  fwrite (plot_stream, data(j:j+3,:), "float64");
	endfor
      else
	for j = 1:3:nr
	  fwrite (plot_stream, data(j:j+2,:), "float64");
	endfor
      endif
    endif
  endif

endfunction

function do_tics (obj, plot_stream, ymirror, mono)

  obj.xticklabel = ticklabel_to_cell (obj.xticklabel);
  obj.yticklabel = ticklabel_to_cell (obj.yticklabel);
  obj.zticklabel = ticklabel_to_cell (obj.zticklabel);

  [fontname, fontsize] = get_fontname_and_size (obj);

  ## A Gnuplot tic scale of 69 is equivalent to Octave's 0.5.
  ticklength = sprintf ("scale %4.1f", (69/0.5)*obj.ticklength(1));

  if (strcmpi (obj.xaxislocation, "top"))
    do_tics_1 (obj.xtickmode, obj.xtick, obj.xminortick, obj.xticklabelmode,
	       obj.xticklabel, obj.xcolor, "x2", plot_stream, true, mono,
	       "border", obj.tickdir, ticklength, fontname, fontsize,
	       obj.interpreter);
    do_tics_1 ("manual", [], "off", obj.xticklabelmode, obj.xticklabel,
	       obj.xcolor, "x", plot_stream, true, mono, "border",
	       "", "", fontname, fontsize, obj.interpreter);
  elseif (strcmpi (obj.xaxislocation, "zero"))
    do_tics_1 (obj.xtickmode, obj.xtick, obj.xminortick, obj.xticklabelmode,
	       obj.xticklabel, obj.xcolor, "x", plot_stream, true, mono,
	       "axis", obj.tickdir, ticklength, fontname, fontsize,
	       obj.interpreter);
    do_tics_1 ("manual", [], "off", obj.xticklabelmode, obj.xticklabel,
	       obj.xcolor, "x2", plot_stream, true, mono, "axis",
	       "", "", fontname, fontsize, obj.interpreter);
  else
    do_tics_1 (obj.xtickmode, obj.xtick, obj.xminortick, obj.xticklabelmode,
	       obj.xticklabel, obj.xcolor, "x", plot_stream, true, mono,
	       "border", obj.tickdir, ticklength, fontname, fontsize,
	       obj.interpreter);
    do_tics_1 ("manual", [], "off", obj.xticklabelmode, obj.xticklabel,
	       obj.xcolor, "x2", plot_stream, true, mono, "border",
	       "", "", fontname, fontsize, obj.interpreter);
  endif
  if (strcmpi (obj.yaxislocation, "right"))
    do_tics_1 (obj.ytickmode, obj.ytick, obj.yminortick, obj.yticklabelmode,
	       obj.yticklabel, obj.ycolor, "y2", plot_stream, ymirror, mono,
	       "border", obj.tickdir, ticklength, fontname, fontsize,
	       obj.interpreter);
    do_tics_1 ("manual", [], "off", obj.yticklabelmode, obj.yticklabel,
	       obj.ycolor, "y", plot_stream, ymirror, mono, "border",
	       "", "", fontname, fontsize, obj.interpreter);
  elseif (strcmpi (obj.xaxislocation, "zero"))
    do_tics_1 (obj.ytickmode, obj.ytick, obj.yminortick, obj.yticklabelmode,
	       obj.yticklabel, obj.ycolor, "y", plot_stream, ymirror, mono,
	       "axis", obj.tickdir, ticklength, fontname, fontsize,
	       obj.interpreter);
    do_tics_1 ("manual", [], "off", obj.yticklabelmode, obj.yticklabel,
	       obj.ycolor, "y2", plot_stream, ymirror, mono, "axis",
	       "", "", fontname, fontsize, obj.interpreter);
  else
    do_tics_1 (obj.ytickmode, obj.ytick, obj.yminortick, obj.yticklabelmode,
	       obj.yticklabel, obj.ycolor, "y", plot_stream, ymirror, mono,
	       "border", obj.tickdir, ticklength, fontname, fontsize,
	       obj.interpreter);
    do_tics_1 ("manual", [], "off", obj.yticklabelmode, obj.yticklabel,
	       obj.ycolor, "y2", plot_stream, ymirror, mono, "border",
	       "", "", fontname, fontsize, obj.interpreter);
  endif
  do_tics_1 (obj.ztickmode, obj.ztick, obj.zminortick, obj.zticklabelmode,
	     obj.zticklabel, obj.zcolor, "z", plot_stream, true, mono,
	     "border", obj.tickdir, ticklength, fontname, fontsize,
	     obj.interpreter);
endfunction

function do_tics_1 (ticmode, tics, mtics, labelmode, labels, color, ax,
		    plot_stream, mirror, mono, axispos, tickdir, ticklength,
		    fontname, fontsize, interpreter)
  persistent warned_latex = false;
  if (strcmpi (interpreter, "tex"))
    for n = 1 : numel(labels)
      labels{n} = __tex2enhanced__ (labels{n}, fontname, false, false);
    endfor
  elseif (strcmpi (interpreter, "latex"))
    if (! warned_latex)
      warning ("latex markup not supported for tick marks");
      warned_latex = true;
    endif
  endif
  if (strcmp (fontname, "*"))
    fontspec = "";
  else
    fontspec = sprintf ("font \"%s,%d\"",  fontname, fontsize);
  endif
  colorspec = get_text_colorspec (color, mono);
  if (strcmpi (ticmode, "manual") || strcmpi (labelmode, "manual"))
    if (isempty (tics))
      fprintf (plot_stream, "unset %stics;\nunset m%stics;\n", ax, ax);
    elseif (strcmpi (labelmode, "manual") && ! isempty (labels))
      if (ischar (labels))
	labels = cellstr (labels);
      endif
      if (isnumeric (labels))
	labels = num2str (real (labels(:)));
      endif
      if (ischar (labels))
	labels = permute (cellstr (labels), [2, 1]);
      endif
      if (iscellstr (labels))
	k = 1;
	ntics = numel (tics);
	nlabels = numel (labels);
	fprintf (plot_stream, "set format %s \"%%s\";\n", ax);
	if (mirror)
	  fprintf (plot_stream, "set %stics %s %s %s mirror (", ax, 
		   tickdir, ticklength, axispos);
	else
	  fprintf (plot_stream, "set %stics %s %s %s nomirror (", ax,
		   tickdir, ticklength, axispos);
	endif
 
	labels = regexprep(labels, "%", "%%");
	for i = 1:ntics
	  fprintf (plot_stream, " \"%s\" %.15g", labels{k++}, tics(i));
	  if (i < ntics)
	    fputs (plot_stream, ", ");
	  endif
	  if (k > nlabels)
	    k = 1;
	  endif
	endfor
	fprintf (plot_stream, ") %s %s;\n", colorspec, fontspec);
 	if (strcmp (mtics, "on"))
	  fprintf (plot_stream, "set m%stics 5;\n", ax);
	else
	  fprintf (plot_stream, "unset m%stics;\n", ax);
	endif
     else
	error ("unsupported type of ticklabel");
      endif
    else
      fprintf (plot_stream, "set format %s \"%%g\";\n", ax);
      if (mirror)
	fprintf (plot_stream, "set %stics %s %s %s mirror (", ax, tickdir,
		 ticklength, axispos);
      else
	fprintf (plot_stream, "set %stics %s %s %s nomirror (", ax, tickdir,
		 ticklength, axispos);
      endif
      fprintf (plot_stream, " %.15g,", tics(1:end-1));
      fprintf (plot_stream, " %.15g) %s;\n", tics(end), fontspec);
      if (strcmp (mtics, "on"))
        fprintf (plot_stream, "set m%stics 5;\n", ax);
      else
	fprintf (plot_stream, "unset m%stics;\n", ax);
      endif
    endif
  else
    fprintf (plot_stream, "set format %s \"%%g\";\n", ax);
    if (mirror)
      fprintf (plot_stream, "set %stics %s %s %s mirror %s %s;\n", ax, 
	       axispos, tickdir, ticklength, colorspec, fontspec);
    else
      fprintf (plot_stream, "set %stics %s %s %s nomirror %s %s;\n", ax, 
	       tickdir, ticklength, axispos, colorspec, fontspec);
    endif
    if (strcmp (mtics, "on"))
      fprintf (plot_stream, "set m%stics 5;\n", ax);
    else
      fprintf (plot_stream, "unset m%stics;\n", ax);
    endif
  endif
endfunction

function ticklabel = ticklabel_to_cell (ticklabel)
  if (! isempty (ticklabel) && ! iscell (ticklabel))
    if (isnumeric (ticklabel))
      ## Use upto 5 significant digits
      ticklabel = num2str (ticklabel(:), 5);
    endif
    ticklabel = cellstr (ticklabel);
  endif
endfunction

function colorspec = get_text_colorspec (color, mono)
  if (mono)
    colorspec = "";
  else
    colorspec = sprintf ("textcolor rgb \"#%02x%02x%02x\"",
			 round (255*color));
  endif
endfunction

function [f, s, fnt, it, bld] = get_fontname_and_size (t)
  if (isempty (t.fontname))
    fnt = "Helvetica";
  else
    fnt = t.fontname;
  endif
  f = fnt;
  it = false;
  bld = false;
  if (! isempty (t.fontweight) && strcmpi (t.fontweight, "bold"))
    if (! isempty(t.fontangle)
	&& (strcmpi (t.fontangle, "italic")
	    || strcmpi (t.fontangle, "oblique")))
      f = cstrcat (f, "-bolditalic");
      it = true;
      bld = true;
    else
      f = cstrcat (f, "-bold");
      bld = true;
    endif
  elseif (! isempty(t.fontangle)
	  && (strcmpi (t.fontangle, "italic")
	      || strcmpi (t.fontangle, "oblique")))
    f = cstrcat (f, "-italic");
    it = true;
  endif
  if (isempty (t.fontsize))
    s = 10;
  else
    s = t.fontsize;
  endif
endfunction

function [str, f, s] = __maybe_munge_text__ (enhanced, obj, fld)

  persistent warned_latex = false;

  if (strcmp (fld, "string"))
    [f, s, fnt, it, bld] = get_fontname_and_size (obj);
  else
    f = "Helvetica";
    s = 10;
    fnt = f;
    it = false;
    bld = false;
  endif

  str = getfield (obj, fld);
  if (enhanced)
    if (strcmpi (obj.interpreter, "tex"))
      str = __tex2enhanced__ (str, fnt, it, bld);
    elseif (strcmpi (obj.interpreter, "latex"))
      if (! warned_latex)
	warning ("latex markup not supported for text objects");
	warned_latex = true;
      endif
    endif
  endif
endfunction

function str = __tex2enhanced__ (str, fnt, it, bld)
  persistent sym = __setup_sym_table__ ();
  persistent flds = fieldnames (sym);

  [s, e, m] = regexp(str,'\\([a-zA-Z]+|0)','start','end','matches');

  for i = length (s) : -1 : 1
    ## special case for "\0"  and replace with "{/Symbol \306}'
    if (strncmp (m{i}, '\0', 2))
      str = cstrcat (str(1:s(i) - 1), '{/Symbol \306}', str(s(i) + 2:end));
    else
      f = m{i}(2:end);
      if (isfield (sym, f))
	g = getfield(sym, f);
	## FIXME The symbol font doesn't seem to support bold or italic
	##if (bld)
	##  if (it)
	##    g = regexprep (g, '/Symbol', '/Symbol-bolditalic');
	##  else
	##    g = regexprep (g, '/Symbol', '/Symbol-bold');
	##  endif
	##elseif (it)
	##  g = regexprep (g, '/Symbol', '/Symbol-italic');
	##endif
        str = cstrcat (str(1:s(i) - 1), g, str(e(i) + 1:end));
      elseif (strncmp (f, "rm", 2))
	bld = false;
	it = false;
        str = cstrcat (str(1:s(i) - 1), '/', fnt, ' ', str(s(i) + 3:end));
      elseif (strncmp (f, "it", 2) || strncmp (f, "sl", 2))
	it = true;
	if (bld)
          str = cstrcat (str(1:s(i) - 1), '/', fnt, '-bolditalic ', 
			str(s(i) + 3:end));
        else
          str = cstrcat (str(1:s(i) - 1), '/', fnt, '-italic ', 
			str(s(i) + 3:end));
        endif
      elseif (strncmp (f, "bf", 2))
	bld = true;
	if (it)
          str = cstrcat (str(1:s(i) - 1), '/', fnt, '-bolditalic ', 
			str(2(i) + 3:end));
        else
          str = cstrcat (str(1:s(i) - 1), '/', fnt, '-bold ', 
			str(s(i) + 3:end));
        endif
      elseif (strcmpi (f, "color"))
	## FIXME Ignore \color but remove trailing {} block as well
	d = strfind(str(e(i) + 1:end),'}');
        if (isempty (d))
	  warning ('syntax error in \color argument');
	else
	  str = cstrcat (str(1:s(i) - 1), str(e(i) + d + 1:end));
        endif
      elseif(strcmpi (f, "fontname"))
	b1 = strfind(str(e(i) + 1:end),'{');
	b2 = strfind(str(e(i) + 1:end),'}');
        if (isempty(b1) || isempty(b2))
	  warning ('syntax error in \fontname argument');
	else
          str = cstrcat (str(1:s(i) - 1), '/', 
			str(e(i)+b1(1) + 1:e(i)+b2(1)-1), '{}',
			str(e(i) + b2(1) + 1:end));
        endif
      elseif(strcmpi (f, "fontsize"))
	b1 = strfind(str(e(i) + 1:end),'{');
	b2 = strfind(str(e(i) + 1:end),'}');
        if (isempty(b1) || isempty(b2))
	  warning ('syntax error in \fontname argument');
	else
          str = cstrcat (str(1:s(i) - 1), '/=', 
			str(e(i)+b1(1) + 1:e(i)+b2(1)-1), '{}',
			str(e(i) + b2(1) + 1:end));
        endif
      else
	## Last desperate attempt to treat the symbol. Look for things
	## like \pix, that should be translated to the symbol Pi and x
	for j = 1 : length (flds)
	  if (strncmp (flds{j}, f, length (flds{j})))
	    g = getfield(sym, flds{j});
	    ## FIXME The symbol font doesn't seem to support bold or italic
	    ##if (bld)
	    ##  if (it)
	    ##    g = regexprep (g, '/Symbol', '/Symbol-bolditalic');
	    ##  else
	    ##    g = regexprep (g, '/Symbol', '/Symbol-bold');
	    ##  endif
	    ##elseif (it)
	    ##  g = regexprep (g, '/Symbol', '/Symbol-italic');
	    ##endif
            str = cstrcat (str(1:s(i) - 1), g, 
	    		  str(s(i) + length (flds{j}) + 1:end));
	    break;
	  endif
	endfor
      endif
    endif
  endfor

  ## Prepend @ to things  things like _0^x or _{-100}^{100} for
  ## alignment But need to put the shorter of the two arguments first.
  ## Carful of nested {} and unprinted characters when defining
  ## shortest.. Don't have to worry about things like ^\theta as they
  ## are already converted to ^{/Symbol q}.

  ## FIXME -- This is a mess... Is it worth it just for a "@" character?

  [s, m] = regexp(str,'[_\^]','start','matches');
  i = 1;
  p = 0;
  while (i < length (s))
    if (i < length(s))
      if (str(s(i) + p + 1) == "{")
	s1 = strfind(str(s(i) + p + 2:end),'{');
	si = 1;
	l1 = strfind(str(s(i) + p + 1:end),'}');
        li = 1;
	while (li <= length (l1) && si <= length (s1))
          if (l1(li) < s1(si))
	    if (li == si)
	      break;
	    endif
	    li++;
	  else
	    si++;
	  endif
	endwhile
	l1 = l1 (min (length(l1), si));
        if (s(i) + l1 + 1 == s(i+1))
	  if (str(s(i + 1) + p + 1) == "{")
	    s2 = strfind(str(s(i + 1) + p + 2:end),'{');
	    si = 1;
	    l2 = strfind(str(s(i + 1) + p + 1:end),'}');
            li = 1;
	    while (li <= length (l2) && si <= length (s2))
              if (l2(li) < s2(si))
		if (li == si)
		  break;
		endif
		li++;
	      else
		si++;
	      endif
	    endwhile
	    l2 = l2 (min (length(l2), si));
	    if (length_string (str(s(i)+p+2:s(i)+p+l1-1)) <=
		length_string(str(s(i+1)+p+2:s(i+1)+p+l2-1)))
	      ## Shortest already first!
	      str = cstrcat (str(1:s(i)+p-1), "@", str(s(i)+p:end));
	    else
	      ## Have to swap sub/super-script to get shortest first.
	      str = cstrcat (str(1:s(i)+p-1), "@", str(s(i+1)+p:s(i+1)+p+l2),
			    str(s(i)+p:s(i)+p+l1), str(s(i+1)+p+l2+1:end));
	    endif
	  else
	    ## Have to swap sub/super-script to get shortest first.
	    str = cstrcat (str(1:s(i)+p-1), "@", str(s(i+1)+p:s(i+1)+p+1),
			  str(s(i)+p:s(i)+p+l1), str(s(i+1)+p+2:end));
	  endif
          i += 2;
	  p ++;
	else
	  i++;
	endif
      else
	if (s(i+1) == s(i) + 2)
	  ## Shortest already first!
	  str = cstrcat (str(1:s(i)+p-1), "@", str(s(i)+p:end));
	  p ++;
          i += 2;
	else
	  i ++;
	endif
      endif
    else
      i ++;
    endif
  endwhile

endfunction

function l = length_string (s)
  l = length (s) - length (strfind(s,'{')) - length (strfind(s,'}'));
  m = regexp (s, '/([\w\-]+|[\w\-]+=\d+)', 'matches');
  if (!isempty (m))
    l = l - sum (cellfun (@length, m));
  endif
endfunction

function sym = __setup_sym_table__ ()
  ## Setup the translation table for TeX to gnuplot enhanced mode.
  sym.forall = '{/Symbol \042}';
  sym.exists = '{/Symbol \044}';
  sym.ni = '{/Symbol \047}';
  sym.cong = '{/Symbol \100}';
  sym.Delta = '{/Symbol D}';
  sym.Phi = '{/Symbol F}';
  sym.Gamma = '{/Symbol G}';
  sym.vartheta = '{/Symbol J}';
  sym.Lambda = '{/Symbol L}';
  sym.Pi = '{/Symbol P}';
  sym.Theta = '{/Symbol Q}';
  sym.Sigma = '{/Symbol S}';
  sym.varsigma = '{/Symbol V}';
  sym.Omega = '{/Symbol W}';
  sym.Xi = '{/Symbol X}';
  sym.Psi = '{/Symbol Y}';
  sym.perp = '{/Symbol \136}';
  sym.alpha = '{/Symbol a}';
  sym.beta = '{/Symbol b}';
  sym.chi = '{/Symbol c}';
  sym.delta = '{/Symbol d}';
  sym.epsilon = '{/Symbol e}';
  sym.phi = '{/Symbol f}';
  sym.gamma = '{/Symbol g}';
  sym.eta = '{/Symbol h}';
  sym.iota = '{/Symbol i}';
  sym.varphi = '{/Symbol j}';
  sym.kappa = '{/Symbol k}';
  sym.lambda = '{/Symbol l}';
  sym.mu = '{/Symbol m}';
  sym.nu = '{/Symbol n}';
  sym.o =  '{/Symbol o}';
  sym.pi = '{/Symbol p}';
  sym.theta = '{/Symbol q}';
  sym.rho = '{/Symbol r}';
  sym.sigma = '{/Symbol s}';
  sym.tau = '{/Symbol t}';
  sym.upsilon = '{/Symbol u}';
  sym.varpi = '{/Symbol v}';
  sym.omega = '{/Symbol w}';
  sym.xi = '{/Symbol x}';
  sym.psi = '{/Symbol y}';
  sym.zeta = '{/Symbol z}';
  sym.sim = '{/Symbol \176}';
  sym.Upsilon = '{/Symbol \241}';
  sym.prime = '{/Symbol \242}';
  sym.leq = '{/Symbol \243}';
  sym.infty = '{/Symbol \245}';
  sym.clubsuit = '{/Symbol \247}';
  sym.diamondsuit = '{/Symbol \250}';
  sym.heartsuit = '{/Symbol \251}';
  sym.spadesuit = '{/Symbol \252}';
  sym.leftrightarrow = '{/Symbol \253}';
  sym.leftarrow = '{/Symbol \254}';
  sym.uparrow = '{/Symbol \255}';
  sym.rightarrow = '{/Symbol \256}';
  sym.downarrow = '{/Symbol \257}';
  sym.circ = '{/Symbol \260}';
  sym.pm = '{/Symbol \261}';
  sym.geq = '{/Symbol \263}';
  sym.times = '{/Symbol \264}';
  sym.propto = '{/Symbol \265}';
  sym.partial = '{/Symbol \266}';
  sym.bullet = '{/Symbol \267}';
  sym.div = '{/Symbol \270}';
  sym.neq = '{/Symbol \271}';
  sym.equiv = '{/Symbol \272}';
  sym.approx = '{/Symbol \273}';
  sym.ldots = '{/Symbol \274}';
  sym.mid = '{/Symbol \275}';
  sym.aleph = '{/Symbol \300}';
  sym.Im = '{/Symbol \301}';
  sym.Re = '{/Symbol \302}';
  sym.wp = '{/Symbol \303}';
  sym.otimes = '{/Symbol \304}';
  sym.oplus = '{/Symbol \305}';
  sym.oslash = '{/Symbol \306}';
  sym.cap = '{/Symbol \307}';
  sym.cup = '{/Symbol \310}';
  sym.supset = '{/Symbol \311}';
  sym.supseteq = '{/Symbol \312}';
  sym.subset = '{/Symbol \314}';
  sym.subseteq = '{/Symbol \315}';
  sym.in = '{/Symbol \316}';
  sym.notin = '{/Symbol \317}';
  sym.angle = '{/Symbol \320}';
  sym.bigtriangledown = '{/Symbol \321}';
  sym.langle = '{/Symbol \341}';
  sym.rangle = '{/Symbol \361}';
  sym.nabla = '{/Symbol \321}';
  sym.prod = '{/Symbol \325}';
  sym.surd = '{/Symbol \326}';
  sym.cdot = '{/Symbol \327}';
  sym.neg = '{/Symbol \330}';
  sym.wedge = '{/Symbol \331}';
  sym.vee = '{/Symbol \332}';
  sym.Leftrightarrow = '{/Symbol \333}';
  sym.Leftarrow = '{/Symbol \334}';
  sym.Uparrow = '{/Symbol \335}';
  sym.Rightarrow = '{/Symbol \336}';
  sym.Downarrow = '{/Symbol \337}';
  sym.diamond = '{/Symbol \340}';
  sym.copyright = '{/Symbol \343}';
  sym.lfloor = '{/Symbol \353}';
  sym.lceil  = '{/Symbol \351}';
  sym.rfloor = '{/Symbol \373}';
  sym.rceil  = '{/Symbol \371}';
  sym.int = '{/Symbol \362}';
endfunction

function retval = __do_enhanced_option__ (enhanced, obj)
  retval = "";
  if (enhanced)
    if (strcmpi (obj.interpreter, "none"))
      retval = "noenhanced";
    else
      retval = "enhanced";
    endif
  endif
endfunction

function typ = get_old_gnuplot_color (color)
  if (isequal (color, [0, 0, 0]))
    typ = -1;
  elseif (isequal (color, [1, 0, 0]))
    typ = 1;
  elseif (isequal (color, [0, 1, 0]))
    typ = 2;
  elseif (isequal (color, [0, 0, 1]))
    typ = 3;
  elseif (isequal (color, [1, 0, 1]))
    typ = 4;
  elseif (isequal (color, [0, 1, 1]))
    typ = 5;
  elseif (isequal (color, [1, 1, 1]))
    typ = -1;
  elseif (isequal (color, [1, 1, 0]))
    typ = 7;
  else
    typ = -1;
  endif
endfunction