🚀 go-pugleaf

When I was using Mathematica, I had written a simple package that
converted 2-d graphs to PicTeX output. However, I'm not certain it
works anymore, since this was with an alpha version of mathematica.

But, dispair not: if you use a dvi printer that uses the ``tpic''
specials (like iptex, for example, or rokickis dvips), the following
TeX macros may be of use. It replaces several functions in pictex and
causes all \plot commands to generate tpic specials rather than wads
of TeX output. I never extended it for quads, circles or ellipses
because I don't use those much.

This
	(a) makes processing mucho faster
	(b) makes printing mucho faster
	(c) maintains portable code, because you can just yank the
	    use of ``texpictex'' and it'll still produce the same
	    output.

%%%%%%%%%% texpictex.tex %%%%%%%%%%
%
% texpictex.tex -- The following macros over-ride certain definitions in the
% PiCTeX macro package. The net effect is that line-drawing is done using
% the \special's used by texpic (tpic). Several DVI printers understand
% and handle these specials.
%
% Currently, only straight lines are translated. Recently, I added a
% clipping routine to clip to the bounding box.
%
% If people extend this to included elliptic circles and quadratics,
% please forward the extensions to me (quads are used in the \arrow
% macro, making them very slow).
%
% Dirk Grunwald
% Univ. of Illinois
% grunwald@m.cs.uiuc.edu
%
\def\makebangletter{\catcode`\!=11\relax}
\def\makebangother{\catcode`\!=12\relax}
%
\makebangletter
%
% The units that texpic deals in. You should define it this way instead
% of simply saying ``0.001in'' because the difference in resolution
% actually makes a big difference
%
\newdimen\!tpu
\!tpu=1in
\divide\!tpu by 1000
%%%
%%	\!maptpus	-- map a PiCTeX dimension to a TeXPiC dimension
%%			using the \!tpu conversion factor.
%%
%%	uses: dimen0
%%
\def\!maptpus#1#2 {\dimen0=#1\divide \dimen0 by \!tpu #2=\dimen0}
%
% **  \setplotsymbol ({PLOTSYMBOL} [ ] < , >)
% **  Save PLOTSYMBOL away in an hbox for use with curve plotting routines
% **  See Subsection 5.2 of the manual.
\def\setplotsymbol(#1#2){%
  \!setputobject{#1}{#2}
  \setbox\!plotsymbol=\box\!putobject%
  \!plotsymbolxshift=\!xshift 
  \!plotsymbolyshift=\!yshift
%
% Additions: compute size of dot, convert to TPUs and issue a pensize
%  
  \!dimenB=\wd\!plotsymbol
  \!dimenC=\ht\!plotsymbol
  \advance\!dimenC by \dp\!plotsymbol
  \ifdim\!dimenB<\!dimenC \!dimenF=\!dimenC  \else \!dimenF=\!dimenB\fi
  \!maptpus{\!dimenF}{\!countC}
  \special{pn \the\!countC}
  \ignorespaces}

\setplotsymbol({\fiverm .})%       ** initialize plotsymbol

% **  The following routine is used to draw a "solid" line between (xS,yS)
% **  and (xE,yE).  Points are spaced nearly every  \plotsymbolspacing length
% **  along the line.  
%
%	Note: this is a replacement for PicTeX \!linearsolid.
%	If line clipping is enabled, the line to be drawn is
%	clipped using \!clipline. If there's anything left
%	to draw after clipping, it's drawn. If clipping is off,
%	the line is simply drawn. In either case, line drawing
%	is done by \!texpicline.
%
\def\!linearsolid{%
%  \typeout{Using texpictex linearsolid}%
  \let\!nextLinearAct=\!texpicline
  \expandafter\ifx \!initinboundscheck \relax
    \else \!clipline \if!InBounds \else \let\!nextLinearAct=\relax \fi \fi%
  \!nextLinearAct%
}
%
% Texpic has increasing origin in the upper left corner, while
% pictex has origin in bottom left corner. Ergo, we flip the signs
% for y-coordinates.
%
\def\!texpicline{%
\advance\!xS by -\!xorigin
\advance\!xE by -\!xorigin
\advance\!yS by -\!yorigin
\advance\!yE by -\!yorigin
\!maptpus{\!xS}{\!countC} \!maptpus{\!yS}{\!countD} \!countD=-\!countD%
\special{pa \the\!countC \space \the\!countD}%
\!maptpus{\!xE}{\!countC} \!maptpus{\!yE}{\!countD} \!countD=-\!countD%
\special{pa \the\!countC \space \the\!countD}\special{fp}%
\ignorespaces}
%
%%%
%	Code to support line clipping
%
%	Line clipping routine. Clips to bounding box specified
%	by (!checkleft, !checkbot) and (!checkright, !checktop).
%	Note that this box is only defined if \initboundscheckon
%	has been called.
%
%	The clipping algorithm was published in ACM TOG Vol 3 No 1
%	by people at Berkeley, but I've forgotten the complete reference.
%	This was translated from a version I wrote in C.
%
%%
%	After calling \!cliplines, !InBounds tells you if the line contains
%	any points within the clipping window.
%
\newif\if!InBounds
%
%%
%	\!clipt	-- this corresponds to the routine by the same name
%	in the published algorithm.
%
%	Dimens used are descibed below. All are grouped and know that
%	PiCTeX doesn't use dimen0..9. Variable names are taken from
%	the TOG article. The junk on the r.h.s. is indenting information
%
%	Globals:	dimen8 corresponds to t0
%			dimen9 corresponds to t1
%
%	clipt		dimen0 corresponds to p
%			dimen1 corresponds to q
%			dimen2 corresponds to r
%
%	!fastclip	Uses bounding boxes
%
%	!clipline	passes dimen3 to clipt as p
%			passes dimen4 to clipt as q
%			uses   dimen0, dimen2
%
%
\def\!clipt#1#2{%
  \dimen0=#1 \relax \dimen1=#2 \relax
  \ifdim \dimen0 < \!zpt%						>0
	\!divide{\dimen1}{\dimen0}{\dimen2}%
	\ifdim \dimen2 > \dimen9%					>1
		\global\!InBoundsfalse
	\else%								=1
		\ifdim \dimen2 > \dimen8 \dimen8=\dimen2 \fi
	\fi%								<1
  \else \ifdim \dimen0 > \!zpt%						=0>1
	\!divide{\dimen1}{\dimen0}{\dimen2}%
	\ifdim \dimen2 < \dimen8%					>2
		\global\!InBoundsfalse
	\else%								=2
		\ifdim \dimen2 < \dimen9 \dimen9=\dimen2 \fi
	\fi%								<2
   \else%								=1
	\ifdim \dimen1 < \!zpt \global\!InBoundsfalse \fi
   \fi%									<1
  \fi%									<0
}
%
%	fastclipcheck
%
\def\!fastclip#1#2{%
  \ifdim #1<\!checkleft \global\!InBoundsfalse \else
    \ifdim #1>\!checkright \global\!InBoundsfalse \else
      \ifdim #2<\!checkbot \global\!InBoundsfalse \else
         \ifdim #2>\!checktop \global\!InBoundsfalse \else
         \fi 
      \fi
    \fi
  \fi}
%
%	clipline	- clip a line to the current bounding box.
%	assumes line is in (!xS, !yS) and extends to (!xE,!yE) and that
%	\!xdiff and \!ydiff has been set up. This is normally done
%	in \!lstart.
%
%	\!clipline first checks to see if the start & end points are
%	conainted in the clipping box. If the simple compare works,
%	then no clipping is done, else \!doclip is called to
%	do the actually clipping computations.
%
\def\!clipline{%
   \!!initinboundscheck
   \!InBoundstrue
   \!fastclip{\!xS}{\!yS}%
   \!fastclip{\!xE}{\!yE}%
   \if!InBounds\else\!doclip\fi}
%
\def\!doclip{%
\begingroup%
  \global\!InBoundstrue%
  \dimen8=0pt
  \dimen9=1pt
  %
  \dimen3=-\!xdiff
  \dimen4=\!xS \advance\dimen4 by -\!checkleft%		fromX-minX
  \!clipt{\dimen3}{\dimen4}%
%
  \if!InBounds% 0
    \dimen3=\!xdiff
    \dimen4=\!checkright \advance\dimen4 by -\!xS%	maxX - fromX
    \!clipt{\dimen3}{\dimen4}%
%
    \if!InBounds% 1
%
      \dimen3=-\!ydiff
      \dimen4=\!yS \advance\dimen4 by -\!checkbot%	fromY-minY
      \!clipt{\dimen3}{\dimen4}%
%
      \if!InBounds% 2
%
        \dimen3=\!ydiff
        \dimen4=\!checktop \advance\dimen4 by -\!yS%	maxY-fromY
        \!clipt{\dimen3}{\dimen4}%
%
	\if!InBounds% 3
	  \dimen0=1pt
%
%	The following \if's truncate the line based on the solution
%	to the parametric solution to the bounding box.
%
%	Note that we don't have a \!multiply, the equivilent to \!divide.
%	The code below compute X * Y as (x / ( 1/ Y)), which is far
%	from optimal.
%
	  \ifdim\dimen9 < \dimen0% 4
	    \ifdim\dimen9=\!zpt%	handle multiply by zero
	     \global\!xE=\!xS
	     \global\!yE=\!yS
	     \!InBoundsfalse%
	    \else
	     \!divide{\dimen0}{\dimen9}{\dimen2}%
%
	     \dimen3=\!xdiff \!divide{\dimen3}{\dimen2}{\dimen4}%
	     \global\!xE=\dimen4 \global\advance\!xE by \!xS
%
	     \dimen3=\!ydiff \!divide{\dimen3}{\dimen2}{\dimen4}%
	     \global\!yE=\dimen4 \global\advance\!yE by \!yS
	    \fi
	  \fi% 4
	  \ifdim\dimen8 > \!zpt% 4
	     \!divide{\dimen0}{\dimen8}{\dimen2}%
%
	     \dimen3=\!xdiff \!divide{\dimen3}{\dimen2}{\dimen4}%
	     \global\advance\!xS by \dimen4
%
	     \dimen3=\!ydiff \!divide{\dimen3}{\dimen2}{\dimen4}%
	     \global\advance\!yS by \dimen4
	  \fi% 4
        \fi% 3
      \fi% 2
    \fi% 1
  \fi% 0
\endgroup}
%
\makebangother