csp-edu: exercises/solutions/pgftree.tex@93fd38efa60f

     1 %    pgftree.tex

     2 %    Version 1.1, 25 Dec 2009

     4 %    Copyright 2009 by David Chiang

     6 %    This program is free software; you can redistribute it and/or modify

     7 %    it under the terms of the GNU General Public License as published by

     8 %    the Free Software Foundation; either version 2 of the License, or

     9 %    (at your option) any later version.

    11 %    This program is distributed in the hope that it will be useful,

    12 %    but WITHOUT ANY WARRANTY; without even the implied warranty of

    13 %    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    14 %    GNU General Public License for more details.

    16 %    You should have received a copy of the GNU General Public License along

    17 %    with this program; if not, write to the Free Software Foundation, Inc.,

    18 %    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

    20 % New in version 1.1:

    21 % - major restructuring to not do arbitrary nesting of subpicture environments

    22 % - sideways trees

    24 % To do:

    25 % - trees with all leaves at same level

    26 % - if \nodename does not exist as desired, wrap inside a rectangle node

    27 % - don't use pgfsubpic internals

    29 \newdimen\levelsep \levelsep=30pt

    30 \newdimen\subtreesep \subtreesep=2pt

    32 \def\leveldirection{down}

    33 \def\siblingdirection{right}

    35 % definitions of growing directions

    36 \def\pgftree@levelshift{\csname pgftree@levelshift@\leveldirection\endcsname}

    37 \def\pgftree@parentanchor{\csname pgftree@parentanchor@\leveldirection\endcsname}

    38 \def\pgftree@childanchor{\csname pgftree@childanchor@\leveldirection\endcsname}

    39 % these assume that the current subpicture is the child

    40 \def\pgftree@presiblingshift{\csname pgftree@presiblingshift@\siblingdirection\endcsname}

    41 \def\pgftree@postsiblingshift{\csname pgftree@postsiblingshift@\siblingdirection\endcsname}

    43 \def\pgftree@levelshift@down{\pgfpoint{0}{-\levelsep}}

    44 \def\pgftree@parentanchor@down{south}

    45 \def\pgftree@childanchor@down{north}

    47 \def\pgftree@levelshift@up{\pgfpoint{0}{\levelsep}}

    48 \def\pgftree@parentanchor@up{north}

    49 \def\pgftree@childanchor@up{south}

    51 \def\pgftree@levelshift@right{\pgfpoint{\levelsep}{0}}

    52 \def\pgftree@parentanchor@right{east}

    53 \def\pgftree@childanchor@right{west}

    55 \def\pgftree@levelshift@left{\pgfpoint{-\levelsep}{0}}

    56 \def\pgftree@parentanchor@left{west}

    57 \def\pgftree@childanchor@left{east}

    59 \def\pgftree@presiblingshift@right{\pgf@process{\pgf@x-\pgf@subpicminx \advance\pgf@x\subtreesep \pgf@y 0pt}}

    60 \def\pgftree@postsiblingshift@right{\pgf@process{\pgf@x\pgf@subpicmaxx \pgf@y 0pt}}

    62 \def\pgftree@presiblingshift@left{\pgf@process{\pgf@x-\pgf@subpicmaxx \advance\pgf@x-\subtreesep \pgf@y 0pt}}

    63 \def\pgftree@postsiblingshift@left{\pgf@process{\pgf@x\pgf@subpicminx \pgf@y 0pt}}

    65 \def\pgftree@presiblingshift@up{\pgf@process{\pgf@x 0pt \pgf@y-\pgf@subpicminy \advance\pgf@y\subtreesep}}

    66 \def\pgftree@postsiblingshift@up{\pgf@process{\pgf@x 0pt \pgf@y\pgf@subpicmaxy}}

    68 \def\pgftree@presiblingshift@down{\pgf@process{\pgf@x 0pt \pgf@y-\pgf@subpicmaxy \advance\pgf@y-\subtreesep}}

    69 \def\pgftree@postsiblingshift@down{\pgf@process{\pgf@x 0pt \pgf@y\pgf@subpicminy}}

    71 % for convenience if you are using \pgftree directly

    72 \def\drawnode#1{\pgfnode{rectangle}{base}{#1}{\nodename}{\pgfusepath{discard}}}

    73 \def\drawedge{%

    74 \pgfpathmoveto{\pgfpointanchor{\parentnodename}{\pgftree@parentanchor}}%

    75 \pgfpathlineto{\pgfpointanchor{\nodename}{\pgftree@childanchor}}%

    76 \pgfusepath{stroke}}

    78 % local variables that we need to assign to inside a \pgfforeach

    79 \newdimen\pgftree@childx

    80 \newdimen\pgftree@savechildx

    81 \newdimen\pgftree@childy

    82 \newdimen\pgftree@savechildy

    83 \newcount\pgftree@childi

    84 \newcount\pgftree@savechildi

    86 %%% \pgftree{subtree}

    88 \def\pgftree#1{%

    89 \def\nodename{r}%

    90 #1%

    91 \pgfplacesubpicture

    92 }

    94 %%% \pgfsubtree{root}{subtrees}

    95 % The first argument draws the root node using PGF/TikZ commands.

    96 % The node must be named \nodename.

    98 % The second argument is an even-length sequence of tokens.

    99 % Token 2n-1 in the sequence draws the nth edge. It should draw an edge from \parentnodename to \nodename.

   100 % Token 2n in the sequence draws the nth subtree. Its root must be named \nodename.

   102 \pgfnewsubpicture{children}

   103 \newdimen\pgftree@lastchildx

   104 \newdimen\pgftree@lastchildy

   106 \def\pgfsubtree#1#2{%

   107 \let\parentnodename\nodename

   108 \pgftree@savechildx=\pgftree@childx

   109 \pgftree@savechildy=\pgftree@childy

   110 \pgftree@savechildi=\pgftree@childi

   111 % Build subpicture with all the children and their subtrees

   112 {\pgftree@childx=0pt%

   113 \pgftree@childy=0pt%

   114 \pgftree@childi=0%

   115 \process@children #2}%

   116 \begin{pgfsubpicture}%

   117 % Create node

   118 #1%

   119 \ifnum\pgftree@childi>0%

   120 % Place children

   121 % move down \levelsep

   122 {\pgftransformshift{\pgftree@levelshift}%

   123 % center so that parent is midway between origins of first and last children

   124 \pgftransformshift{\pgfpointscale{-0.5}{\pgfqpoint{\the\pgftree@childx}{\the\pgftree@childy}}}%

   125 \pgfplacesubpicture}%

   126 % Draw the edges

   127 {\pgftree@childi=0%

   128 \process@edges #2}%

   129 \fi

   130 \end{pgfsubpicture}%

   131 \global\pgftree@childi=\pgftree@savechildi

   132 \global\pgftree@childx=\pgftree@savechildx

   133 \global\pgftree@childy=\pgftree@savechildy

   134 }

   136 \def\process@children{%

   137 \pgfutil@ifnextchar\egroup

   138 {% No more children, step back to origin of last child

   139 \global\pgftree@childx\pgftree@lastchildx

   140 \global\pgftree@childy\pgftree@lastchildy

   141 \global\pgftree@childi\pgftree@childi

   142 \ifnum\pgftree@childi>0%

   143 \pgfrestoresubpicture{children}% pass children back to caller

   144 \fi

   145 }%

   146 {\@process@children}%

   147 }

   148 \def\@process@children#1#2{% #1 is the edge, #2 is the child

   149 % Build the current child

   150 {\edef\nodename{\parentnodename-\the\pgftree@childi}%

   151 #2}%

   152 \begin{pgfsubpicture}%

   153 % Place current child

   154 \ifnum\pgftree@childi>0% the first child is always at 0

   155 \pgftree@presiblingshift \global\advance\pgftree@childx\pgf@x \global\advance\pgftree@childy\pgf@y

   156 \fi

   157 {\pgftransformshift{\pgfqpoint{\the\pgftree@childx}{\the\pgftree@childy}}%

   158 \pgfplacesubpicture}%

   159 \global\pgftree@lastchildx\pgftree@childx

   160 \global\pgftree@lastchildy\pgftree@childy

   161 \pgftree@postsiblingshift \global\advance\pgftree@childx\pgf@x \global\advance\pgftree@childy\pgf@y

   162 % Save the augmented row of children back into "children"

   163 \end{pgfsubpicture}

   164 \ifnum\pgftree@childi>0%

   165 \pgfmergesubpicture{children}

   166 \else

   167 \pgfsavesubpicture{children}%

   168 \fi

   169 \advance\pgftree@childi by 1%

   170 \process@children

   171 }

   173 \def\process@edges{%

   174 \pgfutil@ifnextchar\egroup

   175 {}%

   176 {\@process@edges}%

   177 }

   178 \def\@process@edges#1#2{%

   179 \edef\nodename{\parentnodename-\the\pgftree@childi}%

   180 #1%

   181 \advance\pgftree@childi by 1%

   182 \process@edges

   183 }

   185 \def\subtreeof#1{%

   186 % the subpicture which contains a node also contains exactly its subtree

   187 \csname pgf@sh@pi@#1\endcsname

   188 }

author	Eugen Sawin <sawine@me73.com>
	Sun, 10 Jun 2012 05:35:08 +0200
changeset 20	93fd38efa60f
permissions	-rw-r--r--