/*
 * $Id: metapost.trm,v 1.5.2.4 1999/09/16 16:05:21 lhecking Exp $
 */

/* GNUPLOT - metapost.trm */

/*[
 * Copyright 1990 - 1993, 1998
 *
 * Permission to use, copy, and distribute this software and its
 * documentation for any purpose with or without fee is hereby granted,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.
 *
 * Permission to modify the software is granted, but not the right to
 * distribute the complete modified source code.  Modifications are to
 * be distributed as patches to the released version.  Permission to
 * distribute binaries produced by compiling modified sources is granted,
 * provided you
 *   1. distribute the corresponding source modifications from the
 *    released version in the form of a patch file along with the binaries,
 *   2. add special version identification to distinguish your version
 *    in addition to the base release version number,
 *   3. provide your name and address as the primary contact for the
 *    support of your modified version, and
 *   4. retain our contact information in regard to use of the base
 *    software.
 * Permission to distribute the released version of the source code along
 * with corresponding source modifications in the form of a patch file is
 * granted with same provisions 2 through 4 for binary distributions.
 *
 * This software is provided "as is" without express or implied warranty
 * to the extent permitted by applicable law.
]*/

/* 1999/04/22
 *			GNUPLOT -- metapost.trm
 *
 *			This terminal driver supports:
 *		    		Metapost Commands
 *
 * Based on metafont.trm, written by
 *		Pl Hedne
 *		Trondheim, Norway
 *		Pal.Hedne@termo.unit.no;
 *		with improvements by Carsten Steger
 *
 * and pstricks.trm, written by
 *		David Kotz and Raymond Toy
 *
 * Adapted to metapost by:
 * 		Daniel H. Luecking <luecking@comp.uark.edu> and
 * 	 	L Srinivasa Mohan <mohan@chemeng.iisc.ernet.in>
 */

#include "driver.h"

#ifdef TERM_REGISTER
register_term(mp)
#endif

#ifdef TERM_PROTO
TERM_PUBLIC void MP_options __PROTO((void));
TERM_PUBLIC void MP_init __PROTO((void));
TERM_PUBLIC void MP_graphics __PROTO((void));
TERM_PUBLIC void MP_text __PROTO((void));
TERM_PUBLIC void MP_linetype __PROTO((int linetype));
TERM_PUBLIC void MP_move __PROTO((unsigned int x, unsigned int y));
TERM_PUBLIC void MP_point __PROTO((unsigned int x, unsigned int y, int number));
TERM_PUBLIC void MP_pointsize __PROTO((double size));
TERM_PUBLIC void MP_linewidth __PROTO((double width));
TERM_PUBLIC void MP_vector __PROTO((unsigned int ux, unsigned int uy));
TERM_PUBLIC void MP_arrow __PROTO((unsigned int sx, unsigned int sy,
				   unsigned int ex, unsigned int ey,
				   TBOOLEAN head));
TERM_PUBLIC void MP_put_text __PROTO((unsigned int x, unsigned int y, char str[]));
TERM_PUBLIC int MP_justify_text __PROTO((enum JUSTIFY mode));
TERM_PUBLIC int MP_text_angle __PROTO((int ang));
TERM_PUBLIC void MP_reset __PROTO((void));
TERM_PUBLIC int MP_set_font __PROTO((char *font));
TERM_PUBLIC void MP_boxfill __PROTO((int style,
				     unsigned int x1, unsigned int y1,
				     unsigned int width, unsigned int height));

/* 5 inches wide by 3 inches high (default) */
#define MP_XSIZE 5.0
#define MP_YSIZE 3.0

/* gnuplot units will be one pixel if printing device has this
   resolution */
#define MP_DPI (300)

#define MP_XMAX (MP_XSIZE*MP_DPI)
#define MP_YMAX (MP_YSIZE*MP_DPI)

#define MP_HTIC (5*MP_DPI/72)	/* nominally 5pt   */
#define MP_VTIC (5*MP_DPI/72)	/*    "      5pt   */
#define MP_HCHAR (MP_DPI*53/10/72)	/*    "      5.3pt */
#define MP_VCHAR (MP_DPI*11/72)	/*    "      11pt  */
#endif /* TERM_PROTO */

#ifndef TERM_PROTO_ONLY
#ifdef TERM_BODY

static double MP_xsize = MP_XSIZE;
static double MP_ysize = MP_YSIZE;
/* static double MP_xmax = MP_XMAX;
   static double MP_ymax = MP_YMAX;
 * unused, for now
 */
static int MP_posx;
static int MP_posy;
static char MP_fontname[MAX_ID_LEN + 1];
static double MP_fontsize;
static double MP_textmag;
enum JUSTIFY MP_justify = LEFT;
static int MP_ang = 0;
static int MP_char_code = 0;

/* number of nodes in an output line so far */
static int MP_linecount = 1;

/* Number of point types */
#define MP_POINT_TYPES 10

/* Number of line types */
#define MP_LINE_TYPES 8

/* are we in the middle of a MP path? */
static TBOOLEAN MP_inline = FALSE;
/* colored or dashed lines? */
static TBOOLEAN MP_color = FALSE;
static TBOOLEAN MP_solid = FALSE;

/* compatability mode*/
static TBOOLEAN MP_notex = FALSE;

/* has a font change taken place? */
static TBOOLEAN MP_fontchanged = FALSE;

/* The old types */
static int MP_oldline = -2;

/* The old sizes */
static double MP_oldptsize = 1.0;
static double MP_oldpen = 1.0;

/* terminate any path in progress */
static void MP_endline __PROTO((void));

/* max number of path nodes before a newline */
#define MP_LINEMAX 5

TERM_PUBLIC void
MP_options()
{
    MP_color = FALSE;
    MP_solid = FALSE;
    MP_notex = FALSE;
    MP_fontsize = 10.0;
    MP_textmag = 1.0;
    strcpy(MP_fontname, "cmr10");
    strcpy(default_font, "");	/* output file will store default font info */
    while (!END_OF_COMMAND) {
	if (almost_equals(c_token, "m$onochrome")) {
	    MP_color = FALSE;
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "c$olor") || almost_equals(c_token, "c$olour")) {
	    MP_color = TRUE;
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "s$olid")) {
	    MP_solid = TRUE;
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "da$shed")) {
	    MP_solid = FALSE;
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "n$otex")) {
	    MP_notex = TRUE;
	    strcpy(MP_fontname, "pcrr8r");
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "t$ex")) {
	    MP_notex = FALSE;
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "de$fault")) {
	    c_token++;
	    continue;
	}
	if (almost_equals(c_token, "m$agnification")) {
	    c_token++;
	    if (!END_OF_COMMAND) {	/* global text scaling */
		struct value a;
		MP_textmag = (double) real(const_express(&a));
	    }
	    c_token++;
	    continue;
	}
	break;
    }
    if (!END_OF_COMMAND && isstring(c_token)) {		/* font name */
	quote_str(MP_fontname, c_token, MAX_ID_LEN);
	c_token++;
    }
    if (!END_OF_COMMAND) {	/*font size */
	struct value a;
	MP_fontsize = (double) real(const_express(&a));
	c_token++;
    }
    /* minimal error recovery: */
    if (MP_fontsize < 5.0)
	MP_fontsize = 5.0;
    if (MP_fontsize > 99.99)
	MP_fontsize = 99.99;

    term->v_char = (unsigned int) (MP_DPI * MP_fontsize * MP_textmag * 11 / 720);
    if (MP_notex) {		/* Courier is a little wider than cmtt */
	term->h_char = (unsigned int) (MP_DPI * MP_fontsize * MP_textmag * 6.0 / 720 + 0.5);
    } else {
	term->h_char = (unsigned int) (MP_DPI * MP_fontsize * MP_textmag * 5.3 / 720 + 0.5);
    }
    sprintf(term_options, "%s%s%s%s%6.3f \"%s\" %5.2f",
	    MP_color ? "color " : "", MP_solid ? "solid " : "",
	    MP_notex ? "notex " : "", "mag ",
	    MP_textmag, MP_fontname, MP_fontsize);
}

TERM_PUBLIC void
MP_init()
{
    time_t now;
    time(&now);
    MP_posx = MP_posy = 0;
    fprintf(gpoutfile, "%%GNUPLOT Metapost output: %s\n", asctime(localtime(&now)));
    fputs("\n\
defaultmpt:=mpt:=4;\n\
th:=.6;\n\
\n\
def scalepen expr n = pickup pencircle scaled (n*th) enddef;\n\
def ptsize expr n = mpt:=n*defaultmpt enddef;\n",
	  gpoutfile);

    fprintf(gpoutfile, "\ntextmag:=%6.3f;\n", MP_textmag);

    fputs("\
vardef makepic(expr str) =\n\
  if picture str : str scaled textmag\n\
  % otherwise a string\n\
  else: str infont defaultfont scaled (defaultscale*textmag)\n\
  fi\n\
enddef;\n\
\n\
def	infontsize(expr str, size) =\n\
  infont str scaled (size /	fontsize str)\n\
enddef;\n",
	  gpoutfile);

    if (MP_notex) {
	fprintf(gpoutfile, "\n\
defaultfont:= \"%s\";\n\
defaultscale := %6.3f/fontsize defaultfont;\n",
		MP_fontname, MP_fontsize);
    } else {
	fputs("\n\
%font changes\n\
verbatimtex\n\
  \\def\\setfont#1#2{%.\n\
    \\font\\gpfont=#1 at #2pt\n\
    \\gpfont}\n",
	      gpoutfile);

	fprintf(gpoutfile, "\\setfont{%s}{%5.2f}\netex\n",
		MP_fontname, MP_fontsize);
    }
    fputs("\n\
color currentcolor; currentcolor=black;\n\
boolean colorlines,dashedlines;\n",
	  gpoutfile);
    if (MP_color) {
	fputs("colorlines:=true;\n", gpoutfile);
    } else {
	fputs("colorlines:=false;\n", gpoutfile);
    }
    if (MP_solid) {
	fputs("dashedlines:=false;\n", gpoutfile);
    } else {
	fputs("dashedlines:=true;\n", gpoutfile);
    }
    fputs("\n\
def _wc = withpen currentpen withcolor currentcolor enddef;\n\
def _ac = addto currentpicture enddef;\n\
def _sms = scaled mpt shifted enddef;\n\
% drawing point-types\n\
def gpdraw (expr n, x, y) =\n\
  if n<0: _ac contour fullcircle _sms (x,y)\n\
  elseif (n=1) or (n=3):\n\
    _ac doublepath ptpath[n] _sms (x,y) _wc;\n\
    _ac doublepath ptpath[n] rotated 90 _sms (x,y) _wc\n\
  elseif n<6: _ac doublepath ptpath[n] _sms (x,y) _wc\n\
  else: _ac contour ptpath[n] _sms (x,y) _wc\n\
  fi\n\
enddef;\n\
\n\
% the point shapes\n\
path ptpath[];\n\
%diamond\n\
ptpath0 = ptpath6 = (-1/2,0)--(0,-1/2)--(1/2,0)--(0,1/2)--cycle;\n\
% plus sign\n\
ptpath1 = (-1/2,0)--(1/2,0);\n\
% square\n\
ptpath2 = ptpath7 = (-1/2,-1/2)--(1/2,-1/2)--(1/2,1/2)--(-1/2,1/2)--cycle;\n\
% cross\n\
ptpath3 := (-1/2,-1/2)--(1/2,1/2);\n\
% circle:\n\
ptpath4 = ptpath8:= fullcircle;\n\
% triangle\n\
ptpath5 = ptpath9 := (0,1/2)--(-1/2,-1/2)--(1/2,-1/2)--cycle;\n\
\n\
def linetype expr n =\n\
  currentcolor:= if colorlines : col[n] else: black fi;\n\
  if n = -1 :\n\
      drawoptions(withcolor currentcolor withpen (currentpen scaled .5));\n\
  elseif n < 1 :\n\
    drawoptions(_wc);\n\
  else :\n\
    drawoptions( if dashedlines: dashed lt[n] fi _wc);\n\
  fi\n\
enddef;\n\
\n\
% dash patterns\n\
picture lt[];\n\
lt1=dashpattern(on 2 off 2); % dashes\n\
lt2=dashpattern(on 2 off 2 on 0.2 off 2); %dash-dot\n\
lt3=lt1 scaled 1.414;\n\
lt4=lt2 scaled 1.414;\n\
lt5=lt1 scaled 2;\n\
lt6:=lt2 scaled 2;\n\
lt7=dashpattern(on 0.2 off 2); %dots\n\
\n\
color col[],cyan, magenta, yellow;\n\
cyan=blue+green; magenta=red+blue;yellow=green+red;\n\
col[-2]:=col[-1]:=col0:=black;\n\
col1:=red;\n\
col2:=(.2,.2,1); %blue\n\
col3:=(1,.66,0); %orange\n\
col4:=.85*green;\n\
col5:=.9*magenta;\n\
col6:=0.85*cyan;\n\
col7:=.85*yellow;\n\
\n\
%placing text\n\
picture GPtext;\n\
def put_text(expr pic, x, y, r, j) =\n\
  GPtext:=makepic(pic);\n\
  GPtext:=GPtext shifted\n\
    if j = 1: (-(ulcorner GPtext + llcorner GPtext)/2)\n\
    elseif j = 2: (-center GPtext)\n\
    else: (-(urcorner GPtext + lrcorner GPtext)/2)\n\
    fi\n\
    rotated if r > 0: 90 else: 0 fi;\n\
  draw GPtext shifted (x,y)\n\
enddef;\n",
	  gpoutfile);
}

TERM_PUBLIC void
MP_graphics()
{
    /* initialize "remembered" drawing parameters */
    MP_oldline = -2;
    MP_oldpen = 1.0;
    MP_oldptsize = pointsize;
    fprintf(gpoutfile, "\nbeginfig(%d);\nw:=%gin;h:=%gin;\n",
	    MP_char_code, MP_xsize, MP_ysize);
    fprintf(gpoutfile, "a:=w/%d;b:=h/%d;\n", term->xmax, term->ymax);
    fprintf(gpoutfile, "scalepen 1; ptsize %g;linetype -2;\n", pointsize);
    MP_char_code++;
}

TERM_PUBLIC void
MP_text()
{
    if (MP_inline)
	MP_endline();
    fputs("endfig;\n", gpoutfile);
}

TERM_PUBLIC void
MP_linetype(lt)
int lt;
{
    int linetype = lt;
    if (linetype >= MP_LINE_TYPES)
	linetype %= MP_LINE_TYPES;
    if (MP_inline)
	MP_endline();
    if (MP_oldline != linetype) {
	fprintf(gpoutfile, "linetype %d;\n", linetype);
	MP_oldline = linetype;
    }
}

TERM_PUBLIC void
MP_move(x, y)
unsigned int x;
unsigned int y;
{
    if ((x != MP_posx) || (y != MP_posy)) {
	if (MP_inline)
	    MP_endline();
	MP_posx = x;
	MP_posy = y;
    }				/* else we seem to be there already */
}

TERM_PUBLIC void
MP_point(x, y, pt)
unsigned int x;
unsigned int y;
int pt;
{
    int pointtype = pt;
    if (MP_inline)
	MP_endline();

    /* Print the shape defined by 'number'; number < 0 means
       to use a dot, otherwise one of the defined points. */

    if (pointtype >= MP_POINT_TYPES)
	pointtype %= MP_POINT_TYPES;
    fprintf(gpoutfile, "gpdraw(%d,%da,%db);\n", pointtype, x, y);
}

TERM_PUBLIC void
MP_pointsize(ps)
double ps;
{
    if (MP_oldptsize != ps) {
	if (MP_inline)
	    MP_endline();
	fprintf(gpoutfile, "ptsize %g;\n", ps);
	MP_oldptsize = ps;
    }
}


TERM_PUBLIC void
MP_linewidth(lw)
double lw;
{
    if (MP_oldpen != lw) {
	if (MP_inline)
	    MP_endline();
	fprintf(gpoutfile, "scalepen %g;\n", lw);
	MP_oldpen = lw;
    }
}


TERM_PUBLIC void
MP_vector(ux, uy)
unsigned int ux;
unsigned int uy;
{
    if ((ux == MP_posx) && (uy == MP_posy))
	return;			/* Zero length line */

    if (MP_inline) {
	if (MP_linecount++ >= MP_LINEMAX) {
	    fputs("\n", gpoutfile);
	    MP_linecount = 1;
	}
    } else {
	MP_inline = TRUE;
	fprintf(gpoutfile, "draw (%da,%db)", MP_posx, MP_posy);
	MP_linecount = 2;
    }
    MP_posx = ux;
    MP_posy = uy;
    fprintf(gpoutfile, "--(%da,%db)", MP_posx, MP_posy);
}

static void
MP_endline()
{
    MP_inline = FALSE;
    fprintf(gpoutfile, ";\n");
}

TERM_PUBLIC void
MP_arrow(sx, sy, ex, ey, head)
unsigned int sx;
unsigned int sy;
unsigned int ex;
unsigned int ey;
TBOOLEAN head;
{
    MP_move(sx, sy);
    if (head) {
	fprintf(gpoutfile, "drawarrow (%da,%db)--(%da,%db);\n",
		sx, sy, ex, ey);
    } else if ((sx != ex) || (sy != ey)) {
	fprintf(gpoutfile, "draw (%da,%db)--(%da,%db);\n",
		sx, sy, ex, ey);
    }				/* else: arrow with no length and no head = sound of one hand clapping? */
    MP_posx = ex;
    MP_posy = ey;

}

TERM_PUBLIC void
MP_put_text(x, y, str)
unsigned int x, y;
char str[];
{
    int i, j = 0;
    char *text;

    /* ignore empty strings */
    if (!str || !*str)
	return;

    /* F***. why do drivers need to modify string args? */
    text = gp_alloc(strlen(str)+1, "temp string");
    strcpy(text,str);

    if (MP_inline)
	MP_endline();


    switch (MP_justify) {
    case LEFT:
	j = 1;
	break;
    case CENTRE:
	j = 2;
	break;
    case RIGHT:
	j = 3;
	break;
    }
    if (MP_notex) {
	for (i = 0; i < strlen(text); i++)
	    if (text[i] == '"')
		text[i] = '\'';	/* Replace " with ' */
	if (MP_fontchanged) {
	    fprintf(gpoutfile, "\
put_text(\"%s\" infontsize(\"%s\",%5.2f), %da, %db, %d, %d);\n",
		    text, MP_fontname, MP_fontsize, x, y, MP_ang, j);
	} else {
	    fprintf(gpoutfile, "put_text(\"%s\", %da, %db, %d, %d);\n",
		    text, x, y, MP_ang, j);
	}
    } else if (MP_fontchanged) {
	fprintf(gpoutfile, "\
put_text( btex \\setfont{%s}{%5.2f} %s etex, %da, %db, %d, %d);\n",
		MP_fontname, MP_fontsize, text, x, y, MP_ang, j);
    } else {
	fprintf(gpoutfile, "put_text( btex %s etex, %da, %db, %d, %d);\n",
		text, x, y, MP_ang, j);
    }

    free(text);
}

TERM_PUBLIC int
MP_justify_text(mode)
enum JUSTIFY mode;
{
    MP_justify = mode;
    return (TRUE);
}

TERM_PUBLIC int
MP_text_angle(ang)
int ang;
{
    /* Metapost code does the conversion */
    MP_ang = ang;
    return (TRUE);
}

TERM_PUBLIC int
MP_set_font(font)
char *font;
{
    if (*font) {
	size_t sep = strcspn(font, ",");
	strncpy(MP_fontname, font, sep);
	MP_fontname[sep] = NUL;
	sscanf(&(font[sep + 1]), "%lf", &MP_fontsize);
	if (MP_fontsize < 5)
	    MP_fontsize = 5.0;
	if (MP_fontsize >= 100)
	    MP_fontsize = 99.99;
	/*  */
	MP_fontchanged = TRUE;
    } else {
	MP_fontchanged = FALSE;
    }
    return TRUE;
}


TERM_PUBLIC void
MP_reset()
{
    fputs("end.\n", gpoutfile);
}

TERM_PUBLIC void
MP_boxfill(sty, x1, y1, wd, ht)
int sty;
unsigned int x1, y1, wd, ht;
{
    /* for now simply clear box if sty <= 0, do nothing otherwise */
    if (MP_inline)
	MP_endline();
    if (sty <= 0)
	fprintf(gpoutfile, "\
fill (%da,%db)--(%da,%db)--(%da,%db)--(%da,%db)--cycle withcolor background;\n",
		x1, y1, x1 + wd, y1, x1 + wd, y1 + ht, x1, y1 + ht);
}

#endif /* TERM_BODY */

#ifdef TERM_TABLE

TERM_TABLE_START(mp_driver)
    "mp", "MetaPost plotting standard",
    MP_XMAX, MP_YMAX, MP_VCHAR, MP_HCHAR,
    MP_VTIC, MP_HTIC, MP_options, MP_init, MP_reset,
    MP_text, null_scale, MP_graphics, MP_move, MP_vector,
    MP_linetype, MP_put_text, MP_text_angle,
    MP_justify_text, MP_point, MP_arrow, MP_set_font, MP_pointsize,
    0, 0, 0, MP_boxfill, MP_linewidth
    TERM_TABLE_END(mp_driver)
#undef LAST_TERM
#define LAST_TERM mp_driver

#endif /* TERM_TABLE */
#endif /* TERM_PROTO_ONLY */

#ifdef TERM_HELP
START_HELP(mp)
"1 mp",
"?commands set terminal mpost",
"?set terminal mp",
"?set term mp",
"?terminal mp",
"?term mp",
"?mp",
"?metapost",
"",
" The `mp` driver produces output intended to be input to the Metapost program.",
" Running Metapost on the file creates EPS files containing the plots. By",
" default, Metapost passes all text through TeX.  This has the advantage of",
" allowing essentially  any TeX symbols in titles and labels.",
"",
" The `mp` terminal is selected with a command of the form",
"    set term mp {color} {solid} {notex} {mag <magsize>} {\"<name>\"} {<size>}",
" The option `color` causes lines to be drawn in color (on a printer or display",
" that supports it), `monochrome` (or nothing) selects black lines.  The option",
" `solid` draws solid lines, while `dashed` (or nothing) selects lines with",
" different patterns of dashes.  If `solid` is selected but `color` is not,",
" nearly all lines will be identical.  This may occasionally be useful, so it is",
" allowed.",
"",
" The option `notex` bypasses TeX entirely, therefore no TeX code can be used in",
" labels under this option.  This is intended for use on old plot files or files",
" that make frequent use of common characters like `$` and `%` that require",
" special handling in TeX.",
"",
" Changing font sizes in TeX has no effect on the size of mathematics, and there",
" is no foolproof way to make such a change, except by globally  setting a",
" magnification factor. This is the purpose of the `magnification` option. It",
" must be followed by a scaling factor. All text (NOT the graphs) will be scaled",
" by this factor. Use this if you have math that you want at some size other",
" than the default 10pt. Unfortunately, all math will be the same size, but see",
" the discussion below on editing the MP output. `mag` will also work under",
" `notex` but there seems no point in using it as the font size option (below)",
" works as well.",
"",
" A name in quotes selects the font that will be used when no explicit font is",
" given in a `set label` or `set title`.  A name recognized by TeX (a TFM file",
" exists) must be used.  The default is \"cmr10\" unless `notex` is selected,",
" then it is \"pcrr8r\" (Courier).  Even under `notex`, a TFM file is needed by",
" Metapost. The file `pcrr8r.tfm` is the name given to Courier in LaTeX's psnfss",
" package.  If you change the font from the `notex` default, choose a font that",
" matches the ASCII encoding at least in the range 32-126.  `cmtt10` almost",
" works, but it has a nonblank character in position 32 (space).",
"",
" The size can be any number between 5.0 and 99.99.  If it is omitted, 10.0 is",
" used.  It is advisable to use `magstep` sizes: 10 times an integer or",
" half-integer power of 1.2, rounded to two decimals, because those are the most",
" available sizes of fonts in TeX systems.",
"",
" All the options are optional.  If font information is given, it must be at the",
" end, with size (if present) last.  The size is needed to select a size for the",
" font, even if the font name includes size information.  For example,",
" `set term mp \"cmtt12\"` selects cmtt12 shrunk to the default size 10.  This",
" is probably not what you want or you would have used cmtt10.",
"",
" The following common ascii characters need special treatment in TeX:",
"    $, &, #, %, _;  |, <, >;  ^, ~,  \\, {, and }",
" The five characters $, #, &, _, and % can simply be escaped, e.g., `\\$`.",
" The three characters <, >, and | can be wrapped in math mode, e.g., `$<$`.",
" The remainder require some TeX work-arounds.  Any good book on TeX will give",
" some guidance.",
"",
" If you type your labels inside double quotes, backslashes in TeX code need to",
" be escaped (doubled). Using single quotes will avoid having to do this, but",
" then you cannot use `\\n` for line breaks.  As of this writing, version 3.7 of",
" gnuplot processess titles given in a `plot` command differently than in other",
" places, and backslashes in TeX commands need to be doubled regardless of the",
" style of quotes.",
"",
" Metapost pictures are typically used in TeX documents.  Metapost deals with",
" fonts pretty much the same way TeX does, which is different from most other",
" document preparation programs.  If the picture is included in a LaTeX document",
" using the graphics package, or in a plainTeX document via epsf.tex, and then",
" converted to PostScript with dvips (or other dvi-to-ps converter), the text in",
" the plot will usually be handled correctly.  However, the text may not appear",
" if you send the Metapost output as-is to a PostScript interpreter.",
"",
"2 Metapost Instructions",
"?commands set terminal mp detailed",
"?set terminal mp detailed",
"?set term mp detailed",
"?mp detailed",
"?metapost detailed",
"",
" - Set your terminal to Metapost, e.g.:",
"    set terminal mp mono \"cmtt12\" 12",
"",
" - Select an output-file, e.g.:",
"    set output \"figure.mp\"",
"",
" - Create your pictures.  Each plot (or multiplot group) will generate a",
" separate Metapost beginfig...endfig group.  Its default size will be 5 by 3",
" inches.  You can change the size by saying `set size 0.5,0.5` or whatever",
" fraction of the default size you want to have.",
"",
" - Quit gnuplot.",
"",
" - Generate EPS files by running Metapost on the output of gnuplot:",
"    mpost figure.mp  OR  mp figure.mp",
" The name of the Metapost program depends on the system, typically `mpost` for",
" a Unix machine and `mp` on many others.  Metapost will generate one EPS file",
" for each picture.",
"",
" - To include your pictures in your document you can use the graphics package",
" in LaTeX or epsf.tex in plainTeX:",
"    \\usepackage{graphics} % LaTeX",
"    \\input epsf.tex       % plainTeX",
" If you use a driver other than dvips for converting TeX DVI output to PS, you",
" may need to add the following line in your LaTeX document:",
"    \\DeclareGraphicsRule{*}{eps}{*}{}",
" Each picture you made is in a separate file.  The first picture is in, e.g.,",
" figure.0, the second in figure.1, and so on....  To place the third picture in",
" your document, for example, all you have to do is:",
"    \\includegraphics{figure.2} % LaTeX",
"    \\epsfbox{figure.2}         % plainTeX",
"",
" The advantage, if any, of the mp terminal over a postscript terminal is",
" editable output.  Considerable effort went into making this output as clean as",
" possible.  For those knowledgeable in the Metapost language, the default line",
" types and colors can be changed by editing the arrays `lt[]` and `col[]`.",
" The choice of solid vs dashed lines, and color vs black lines can be change by",
" changing the values assigned to the booleans `dashedlines` and `colorlines`.",
" If the default `tex` option was in effect, global changes to the text of",
" labels can be achieved by editing the `vebatimtex...etex` block.  In",
" particular, a LaTeX preamble can be added if desired, and then LaTeX's",
" built-in size changing commands can be used for maximum flexibility. Be sure",
" to set the appropriate MP configuration variable to force Metapost to run",
" LaTeX instead of plainTeX."
END_HELP(mp)
#endif /* TERM_HELP */