% BEZIER DOCUMENT-STYLE OPTION - released 17 December 1985
%    for LaTeX version 2.09
% Copyright (C) 1985 by Leslie Lamport
 
%  In a picture environment, writing
%
%       \bezier{N}(AX,AY)(BX,BY)(CX,CY)
%
%  plots a quadratic Bezier curve from (AX,AY) to (CX,CY), with (BX,BY)
%  as the third Bezier point, using N+1 equally spaced points.
%
%  \bezier{N}(AX,AY)(BX,BY)(CX,CY) ==
%    BEGIN
%      @sc  := N
%      @scp := @sc+1
%      \@xb := 2 * (BX - AX) * \unitlength
%      \@xa := ((CX-AX)*\unitlength - \@xb)/@sc
%      \@yb := 2 * (BY - AY) * \unitlength
%      \@ya := ((CY-AY)*\unitlength - \@yb)/@sc
%      \@pt := square rule of width \@wholewidth
%      @t := 0
%      WHILE @t < @scp
%        DO  \@x := ((@t*\@xa + @xb) / @sc) * t
%            \@y := ((@t*\@ya + @yb) / @sc) * t
%            plot pt with relative coords (\@x,\@y)
%            @t := @t+1
%        OD
 
\newcounter{@sc}
\newcounter{@scp}
\newcounter{@t}
\newlength{\@x}
\newlength{\@xa}
\newlength{\@xb}
\newlength{\@y}
\newlength{\@ya}
\newlength{\@yb}
\newsavebox{\@pt}
 
\def\bezier#1(#2,#3)(#4,#5)(#6,#7){\c@@sc#1\relax
  \c@@scp\c@@sc \advance\c@@scp\@ne
  \@xb #4\unitlength \advance\@xb -#2\unitlength \multiply\@xb \tw@
  \@xa #6\unitlength \advance\@xa -#2\unitlength
      \advance\@xa -\@xb \divide\@xa\c@@sc
  \@yb #5\unitlength \advance\@yb -#3\unitlength \multiply\@yb \tw@
  \@ya #7\unitlength \advance\@ya -#3\unitlength
      \advance\@ya -\@yb \divide\@ya\c@@sc
  \setbox\@pt\hbox{\vrule height\@halfwidth  depth\@halfwidth
   width\@wholewidth}\c@@t\z@
   \put(#2,#3){\@whilenum{\c@@t<\c@@scp}\do
      {\@x\c@@t\@xa \advance\@x\@xb \divide\@x\c@@sc \multiply\@x\c@@t
       \@y\c@@t\@ya \advance\@y\@yb \divide\@y\c@@sc \multiply\@y\c@@t
       \raise \@y \hbox to \z@{\hskip \@x\unhcopy\@pt\hss}%
       \advance\c@@t\@ne}}}
 
 
%  of commands of the type specified below, does the following,
%  where t, dt, dx, and dy are counters,
%
%        t  := 0
%        dt := DT
%        dx := 0
%        dy := 0
%        WHILE t < MAX
%          DO  plot the point (X + (dx/SCALE)), Y + (dy/SCALE))
%              t := t + dt
%              execute COMMANDS
%          OD
%
% COMMANDS may include only the commands \set, \add, \mul, or \div,
% defined as follows, where
%           CTR == counter name,
%           VAL == either an integer (like 2145 or -7), or
%                  \value{CTR'}, where CTR' a counter name, or
%                  -\value{CTR'}
%
%      \set{CTR}{VAL}
%         This command performs the operation  CTR := VAL
%
%      \add{CTR}{VAL}
%          Performs the operation  CTR := CTR + VAL
%
%      \mul{CTR}{VAL}
%          Performs the operation  CTR := CTR * VAL
%
%      \div{CTR}{VAL}
%          Performs the operation  CTR := CTR / VAL
%          (this is integer division, with 5/3 = 1 and
%           -5/3 = 5/(-3) = -1)
%
%  There should be no spaces in COMMANDS.  However, the command \  can
%  be used for readabiilty--e.g.,
%       \set{foo}{dt}\  \mul{foo}{3}
%
%
%  HINTS:
%    \plot'ing takes a long time, so start with DT large, and make it
%     small only for the final draft.
%
 
%\newcounter{t}
%\newcounter{dt}
%\newcounter{dx}
%\newcounter{dy}
%
%\def\set#1#2{\csname c@#1\endcsname#2}
%\def\@div#1#2{\divide\csname c@#1\endcsname#2}
%\def\mul#1#2{\multiply\csname c@#1\endcsname#2}
%\def\add#1#2{\advance\csname c@#1\endcsname#2}
%
 
 
 
%\def\plot#1#2#3#4{\let\div\@div \def\ {}\c@t\z@ \c@t\z@
%  \c@dt#1\c@dx\z@ \c@dy\z@\edef\@tempa{#4}\@tempdima\unitlength
%  \divide\@tempdima #3\relax
%  \setbox\@pt\hbox{\vrule height\@halfwidth  depth\@halfwidth
%   width\@wholewidth}\@whilenum{\c@t<#2}\do
%  {\raise \c@dy\@tempdima \hbox to \z@{\hskip \c@dx\@tempdima
%                                       \unhcopy\@pt\hss
%                                      }\advance\c@t\c@dt\@tempa}}
%

\endinput