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diff --git a/Master/texmf-dist/doc/generic/pgf/text-en/pgfmanual-en-tutorial-nodes.tex b/Master/texmf-dist/doc/generic/pgf/text-en/pgfmanual-en-tutorial-nodes.tex
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--- a/Master/texmf-dist/doc/generic/pgf/text-en/pgfmanual-en-tutorial-nodes.tex
+++ b/Master/texmf-dist/doc/generic/pgf/text-en/pgfmanual-en-tutorial-nodes.tex
@@ -1,4 +1,4 @@
-% Copyright 2006 by Tilo Tantau
+% Copyright 2006 by Till Tantau
%
% This file may be distributed and/or modified
%
@@ -7,27 +7,27 @@
%
% See the file doc/generic/pgf/licenses/LICENSE for more details.
+
\section{Tutorial: A Petri-Net for Hagen}
-In this second tutorial we explore the node mechanism of
-\tikzname\ and \pgfname.
+In this second tutorial we explore the node mechanism of \tikzname\ and
+\pgfname.
-Hagen must give a talk tomorrow about his favorite formalism for
-distributed systems: Petri nets! Hagen used to give his talks using a
-blackboard and everyone seemed to be perfectly content with
-this. Unfortunately, his audience has been spoiled recently with fancy
-projector-based presentations and there seems to be a certain amount
-of peer pressure that his Petri nets should also be drawn using a
-graphic program. One of the professors at his institute recommends
-\tikzname\ for this and Hagen decides to give it a try.
+Hagen must give a talk tomorrow about his favorite formalism for distributed
+systems: Petri nets! Hagen used to give his talks using a blackboard and
+everyone seemed to be perfectly content with this. Unfortunately, his audience
+has been spoiled recently with fancy projector-based presentations and there
+seems to be a certain amount of peer pressure that his Petri nets should also
+be drawn using a graphic program. One of the professors at his institute
+recommends \tikzname\ for this and Hagen decides to give it a try.
\subsection{Problem Statement}
-For his talk, Hagen wishes to create a graphic that demonstrates how a
-net with place capacities can be simulated by a net without
-capacities. The graphic should look like this, ideally:
-
+For his talk, Hagen wishes to create a graphic that demonstrates how a net with
+place capacities can be simulated by a net without capacities. The graphic
+should look like this, ideally:
+%
\begin{quote}
\begin{tikzpicture}
[node distance=1.3cm,>=stealth',bend angle=45,auto,
@@ -119,26 +119,24 @@ capacities. The graphic should look like this, ideally:
\subsection{Setting up the Environment}
-For the picture Hagen will need to load the \tikzname\ package as did
-Karl in the previous tutorial. However, Hagen will also need to load
-some additional \emph{library packages} that Karl did not need. These
-library packages contain additional definitions like extra arrow tips
-that are typically not needed in a picture and that need to be
-loaded explicitly.
+For the picture Hagen will need to load the \tikzname\ package as did Karl in
+the previous tutorial. However, Hagen will also need to load some additional
+\emph{library packages} that Karl did not need. These library packages contain
+additional definitions like extra arrow tips that are typically not needed in a
+picture and that need to be loaded explicitly.
-Hagen will need to load several libraries: The |arrows| library for the
-special arrow tip used in the graphic, the |decoration.pathmorphing|
-library for the ``snaking line'' in the middle, the |backgrounds|
-library for the two rectangular areas that are behind the two main
-parts of the picture, the |fit| library to easily compute the sizes of
-these rectangles, and the |positioning| library for placing nodes
-relative to other nodes.
+Hagen will need to load several libraries: The |arrows| library for the special
+arrow tip used in the graphic, the |decorations.pathmorphing| library for the
+``snaking line'' in the middle, the |backgrounds| library for the two
+rectangular areas that are behind the two main parts of the picture, the |fit|
+library to easily compute the sizes of these rectangles, and the |positioning|
+library for placing nodes relative to other nodes.
\subsubsection{Setting up the Environment in \LaTeX}
When using \LaTeX\ use:
-
+%
\begin{codeexample}[code only]
\documentclass{article} % say
@@ -156,7 +154,7 @@ When using \LaTeX\ use:
\subsubsection{Setting up the Environment in Plain \TeX}
When using plain \TeX\ use:
-
+%
\begin{codeexample}[code only]
%% Plain TeX file
\input tikz.tex
@@ -173,7 +171,8 @@ When using plain \TeX\ use:
\subsubsection{Setting up the Environment in Con\TeX t}
-When using Con\TeX, use:
+When using Con\TeX t, use:
+%
\begin{codeexample}[code only]
%% ConTeXt file
\usemodule[tikz]
@@ -187,41 +186,39 @@ When using Con\TeX, use:
\end{codeexample}
-
\subsection{Introduction to Nodes}
-In principle, we already know how to create the graphics that Hagen
-desires (except perhaps for the snaked line, we will come to that): We
-start with big light gray rectangle and then add lots of circles and
-small rectangle, plus some arrows.
-
-However, this approach has numerous disadvantages: First, it is hard
-to change anything at a later stage. For example, if we decide to add
-more places to the Petri nets (the circles are called places in Petri
-net theory), all of the coordinates change and we need to recalculate
-everything. Second, it is hard to read the code for the Petri net as it is just a long and complicated list of coordinates and drawing
-commands -- the underlying structure of the Petri net is lost.
-
-Fortunately, \tikzname\ offers a powerful mechanism for avoiding the
-above problems: nodes. We already came across nodes in the previous
-tutorial, where we used them to add labels to Karl's graphic. In the
-present tutorial we will see that nodes are much more powerful.
-
-A node is a small part of a picture. When a node is created, you
-provide a position where the node should be drawn and a
-\emph{shape}. A node of shape |circle| will be drawn as a circle, a
-node of shape |rectangle| as a rectangle, and so on. A node may also
-contain some text, which is why Karl used nodes to show text. Finally,
-a node can get a \emph{name} for later reference.
-
-In Hagen's picture we will use nodes for the places and for the
-transitions of the Petri net (the places are the circles, the
-transitions are the rectangles). Let us start with the upper half of
-the left Petri net. In this upper half we have three places and two
-transitions. Instead of drawing three circles and two rectangles, we
-use three nodes of shape |circle| and two nodes of shape
+In principle, we already know how to create the graphics that Hagen desires
+(except perhaps for the snaked line, we will come to that): We start with big
+light gray rectangle and then add lots of circles and small rectangle, plus
+some arrows.
+
+However, this approach has numerous disadvantages: First, it is hard to change
+anything at a later stage. For example, if we decide to add more places to the
+Petri nets (the circles are called places in Petri net theory), all of the
+coordinates change and we need to recalculate everything. Second, it is hard to
+read the code for the Petri net as it is just a long and complicated list of
+coordinates and drawing commands -- the underlying structure of the Petri net
+is lost.
+
+Fortunately, \tikzname\ offers a powerful mechanism for avoiding the above
+problems: nodes. We already came across nodes in the previous tutorial, where
+we used them to add labels to Karl's graphic. In the present tutorial we will
+see that nodes are much more powerful.
+
+A node is a small part of a picture. When a node is created, you provide a
+position where the node should be drawn and a \emph{shape}. A node of shape
+|circle| will be drawn as a circle, a node of shape |rectangle| as a rectangle,
+and so on. A node may also contain some text, which is why Karl used nodes to
+show text. Finally, a node can get a \emph{name} for later reference.
+
+In Hagen's picture we will use nodes for the places and for the transitions of
+the Petri net (the places are the circles, the transitions are the rectangles).
+Let us start with the upper half of the left Petri net. In this upper half we
+have three places and two transitions. Instead of drawing three circles and two
+rectangles, we use three nodes of shape |circle| and two nodes of shape
|rectangle|.
-
+%
\begin{codeexample}[]
\begin{tikzpicture}
\path ( 0,2) node [shape=circle,draw] {}
@@ -232,51 +229,45 @@ use three nodes of shape |circle| and two nodes of shape
\end{tikzpicture}
\end{codeexample}
-Hagen notes that this does not quite look like the final picture, but
-it seems like a good first step.
-
-Let us have a more detailed look at the code. The whole picture
-consists of a single path. Ignoring the |node| operations, there is not
-much going on in this path: It is just a sequence of coordinates with
-nothing ``happening'' between them. Indeed, even if something were to
-happen like a line-to or a curve-to, the |\path| command would not
-``do'' anything with the resulting path. So, all the magic must be in
-the |node| commands.
-
-In the previous tutorial we learned that a |node| will add a piece of
-text at the last coordinate. Thus, each of the five nodes is added at
-a different position. In the above code, this text is empty
-(because of the empty |{}|). So, why do we see anything at all? The
-answer is the |draw| option for the |node| operation: It causes the
-``shape around the text'' to be drawn.
-
-So, the code |(0,2) node [shape=circle,draw] {}| means the following:
-``In the main path, add a move-to to the coordinate |(0,2)|. Then,
-temporarily suspend the construction of the main path while the node
-is built. This node will be a |circle| around an empty text. This
-circle is to be |draw|n, but not filled or otherwise used. Once this
-whole node is constructed, it is saved until after the
-main path is finished. Then, it is drawn.'' The following
-|(0,1) node [shape=circle,draw] {}| then has the following effect:
-``Continue the main path with a move-to to |(0,1)|. Then construct a
-node at this position also. This node is also shown after the main
-path is finished.'' And so on.
-
+Hagen notes that this does not quite look like the final picture, but it seems
+like a good first step.
+
+Let us have a more detailed look at the code. The whole picture consists of a
+single path. Ignoring the |node| operations, there is not much going on in this
+path: It is just a sequence of coordinates with nothing ``happening'' between
+them. Indeed, even if something were to happen like a line-to or a curve-to,
+the |\path| command would not ``do'' anything with the resulting path. So, all
+the magic must be in the |node| commands.
+
+In the previous tutorial we learned that a |node| will add a piece of text at
+the last coordinate. Thus, each of the five nodes is added at a different
+position. In the above code, this text is empty (because of the empty |{}|).
+So, why do we see anything at all? The answer is the |draw| option for the
+|node| operation: It causes the ``shape around the text'' to be drawn.
+
+So, the code |(0,2) node [shape=circle,draw] {}| means the following: ``In the
+main path, add a move-to to the coordinate |(0,2)|. Then, temporarily suspend
+the construction of the main path while the node is built. This node will be a
+|circle| around an empty text. This circle is to be |draw|n, but not filled or
+otherwise used. Once this whole node is constructed, it is saved until after
+the main path is finished. Then, it is drawn.'' The following
+|(0,1) node [shape=circle,draw] {}| then has the following effect: ``Continue
+the main path with a move-to to |(0,1)|. Then construct a node at this position
+also. This node is also shown after the main path is finished.'' And so on.
\subsection{Placing Nodes Using the At Syntax}
-Hagen now understands how the |node| operation adds nodes to the path,
-but it seems a bit silly to create a path using the |\path| operation,
-consisting of numerous superfluous move-to operations, only to place
-nodes. He is pleased to learn that there are ways to add nodes in a
-more sensible manner.
-
-First, the |node| operation allows one to add
-|at (|\meta{coordinate}|)| in order to directly specify where the node
-should be placed, sidestepping the rule that nodes are placed on the
-last coordinate. Hagen can then write the following:
+Hagen now understands how the |node| operation adds nodes to the path, but it
+seems a bit silly to create a path using the |\path| operation, consisting of
+numerous superfluous move-to operations, only to place nodes. He is pleased to
+learn that there are ways to add nodes in a more sensible manner.
+First, the |node| operation allows one to add |at (|\meta{coordinate}|)| in
+order to directly specify where the node should be placed, sidestepping the
+rule that nodes are placed on the last coordinate. Hagen can then write the
+following:
+%
\begin{codeexample}[]
\begin{tikzpicture}
\path node at ( 0,2) [shape=circle,draw] {}
@@ -287,11 +278,11 @@ last coordinate. Hagen can then write the following:
\end{tikzpicture}
\end{codeexample}
-Now Hagen is still left with a single empty path, but at least the
-path no longer contains strange move-tos. It turns out that this can
-be improved further: The |\node| command is an abbreviation for
-|\path node|, which allows Hagen to write:
-
+Now Hagen is still left with a single empty path, but at least the path no
+longer contains strange move-to's. It turns out that this can be improved
+further: The |\node| command is an abbreviation for |\path node|, which allows
+Hagen to write:
+%
\begin{codeexample}[]
\begin{tikzpicture}
\node at ( 0,2) [circle,draw] {};
@@ -302,18 +293,17 @@ be improved further: The |\node| command is an abbreviation for
\end{tikzpicture}
\end{codeexample}
-Hagen likes this syntax much better than the previous one. Note that
-Hagen has also omitted the |shape=| since, like |color=|, \tikzname\
-allows you to omit the |shape=| if there is no confusion.
-
+Hagen likes this syntax much better than the previous one. Note that Hagen has
+also omitted the |shape=| since, like |color=|, \tikzname\ allows you to omit
+the |shape=| if there is no confusion.
\subsection{Using Styles}
-Feeling adventurous, Hagen tries to make the nodes look nicer. In the
-final picture, the circles and rectangle should be filled with
-different colors, resulting in the following code:
-
+Feeling adventurous, Hagen tries to make the nodes look nicer. In the final
+picture, the circles and rectangle should be filled with different colors,
+resulting in the following code:
+%
\begin{codeexample}[]
\begin{tikzpicture}[thick]
\node at ( 0,2) [circle,draw=blue!50,fill=blue!20] {};
@@ -324,14 +314,14 @@ different colors, resulting in the following code:
\end{tikzpicture}
\end{codeexample}
-While this looks nicer in the picture, the code starts to get a bit
-ugly. Ideally, we would like our code to transport the message ``there
-are three places and two transitions'' and not so much which
-filling colors should be used.
-
-To solve this problem, Hagen uses styles. He defines a style for
-places and another style for transitions:
+While this looks nicer in the picture, the code starts to get a bit ugly.
+Ideally, we would like our code to transport the message ``there are three
+places and two transitions'' and not so much which filling colors should be
+used.
+To solve this problem, Hagen uses styles. He defines a style for places and
+another style for transitions:
+%
\begin{codeexample}[]
\begin{tikzpicture}
[place/.style={circle,draw=blue!50,fill=blue!20,thick},
@@ -347,13 +337,13 @@ places and another style for transitions:
\subsection{Node Size}
-Before Hagen starts naming and connecting the nodes, let us first
-make sure that the nodes get their final appearance. They are still
-too small. Indeed, Hagen wonders why they have any size at all, after
-all, the text is empty. The reason is that \tikzname\ automatically
-adds some space around the text. The amount is set using the option
-|inner sep|. So, to increase the size of the nodes, Hagen could write:
-
+Before Hagen starts naming and connecting the nodes, let us first make sure
+that the nodes get their final appearance. They are still too small. Indeed,
+Hagen wonders why they have any size at all, after all, the text is empty. The
+reason is that \tikzname\ automatically adds some space around the text. The
+amount is set using the option |inner sep|. So, to increase the size of the
+nodes, Hagen could write:
+%
\begin{codeexample}[]
\begin{tikzpicture}
[inner sep=2mm,
@@ -367,22 +357,20 @@ adds some space around the text. The amount is set using the option
\end{tikzpicture}
\end{codeexample}
-However, this is not really the best way to achieve the desired
-effect. It is much better to use the |minimum size| option
-instead. This option allows Hagen to specify a minimum size that the
-node should have. If the node actually needs to be bigger because of
-a longer text, it will be larger, but if the text is empty, then the
-node will have |minimum size|. This option is also useful to ensure
-that several nodes containing different amounts of text have the same
-size. The options |minimum height| and |minimum width| allow you to
-specify the minimum height and width independently.
-
-So, what Hagen needs to do is to provide |minimum size| for the
-nodes. To be on the safe side, he also sets |inner sep=0pt|. This
-ensures that the nodes will really have size |minimum size| and not,
-for very small minimum sizes, the minimal size necessary to encompass
-the automatically added space.
-
+However, this is not really the best way to achieve the desired effect. It is
+much better to use the |minimum size| option instead. This option allows Hagen
+to specify a minimum size that the node should have. If the node actually needs
+to be bigger because of a longer text, it will be larger, but if the text is
+empty, then the node will have |minimum size|. This option is also useful to
+ensure that several nodes containing different amounts of text have the same
+size. The options |minimum height| and |minimum width| allow you to specify the
+minimum height and width independently.
+
+So, what Hagen needs to do is to provide |minimum size| for the nodes. To be on
+the safe side, he also sets |inner sep=0pt|. This ensures that the nodes will
+really have size |minimum size| and not, for very small minimum sizes, the
+minimal size necessary to encompass the automatically added space.
+%
\begin{codeexample}[]
\begin{tikzpicture}
[place/.style={circle,draw=blue!50,fill=blue!20,thick,
@@ -398,24 +386,22 @@ the automatically added space.
\end{codeexample}
-
-
\subsection{Naming Nodes}
-Hagen's next aim is to connect the nodes using arrows. This seems like
-a tricky business since the arrows should not start in the middle of
-the nodes, but somewhere on the border and Hagen would very much like
-to avoid computing these positions by hand.
+Hagen's next aim is to connect the nodes using arrows. This seems like a tricky
+business since the arrows should not start in the middle of the nodes, but
+somewhere on the border and Hagen would very much like to avoid computing these
+positions by hand.
-Fortunately, \pgfname\ will perform all the necessary calculations for
-him. However, he first has to assign names to the nodes so that he can
-reference them later on.
-
-There are two ways to name a node. The first is to use the |name=|
-option. The second method is to write the desired name in parentheses
-after the |node| operation. Hagen thinks that this second method seems
-strange, but he will soon change his opinion.
+Fortunately, \pgfname\ will perform all the necessary calculations for him.
+However, he first has to assign names to the nodes so that he can reference
+them later on.
+There are two ways to name a node. The first is to use the |name=| option. The
+second method is to write the desired name in parentheses after the |node|
+operation. Hagen thinks that this second method seems strange, but he will soon
+change his opinion.
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -433,17 +419,17 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-Hagen is pleased to note that the names help in understanding the
-code. Names for nodes can be pretty arbitrary, but they should not
-contain commas, periods, parentheses, colons, and some other special
-characters. However, they can contain underscores and hyphens.
-
-The syntax for the |node| operation is quite liberal with respect to
-the order in which node names, the |at| specifier, and the options
-must come. Indeed, you can even have multiple option blocks between
-the |node| and the text in curly braces, they accumulate. You can
-rearrange them arbitrarily and perhaps the following might be preferable:
+Hagen is pleased to note that the names help in understanding the code. Names
+for nodes can be pretty arbitrary, but they should not contain commas, periods,
+parentheses, colons, and some other special characters. However, they can
+contain underscores and hyphens.
+The syntax for the |node| operation is quite liberal with respect to the order
+in which node names, the |at| specifier, and the options must come. Indeed, you
+can even have multiple option blocks between the |node| and the text in curly
+braces, they accumulate. You can rearrange them arbitrarily and perhaps the
+following might be preferable:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -461,17 +447,16 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
}
-
\subsection{Placing Nodes Using Relative Placement}
-Although Hagen still wishes to connect the nodes, he first wishes to
-address another problem again: The placement of the nodes. Although he
-likes the |at| syntax, in this particular case he would prefer placing
-the nodes ``relative to each other.'' So, Hagen would like to say that
-the |critical 1| node should be below the |waiting 1| node, wherever
-the |waiting 1| node might be. There are different ways of achieving
-this, but the nicest one in Hagen's case is the |below| option:
-
+Although Hagen still wishes to connect the nodes, he first wishes to address
+another problem again: The placement of the nodes. Although he likes the |at|
+syntax, in this particular case he would prefer placing the nodes ``relative to
+each other''. So, Hagen would like to say that the |critical 1| node should be
+below the |waiting 1| node, wherever the |waiting 1| node might be. There are
+different ways of achieving this, but the nicest one in Hagen's case is the
+|below| option:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -488,28 +473,27 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-With the |positioning| library loaded, when an option like |below|
-is followed by |of|, then the position of the node is shifted in
-such a manner that it is placed at the distance |node distance| in the
-specified direction of the given direction. The |node distance| is
-either the distance between the centers of the nodes (when the
-|on grid| option is set to true) or the distance between the borders
-(when the |on grid| option is set to false, which is the default).
-
-Even though the above code has the same effect as the earlier code, Hagen
-can pass it to his colleagues who will be able to just read and
-understand it, perhaps without even having to see the picture.
+With the |positioning| library loaded, when an option like |below| is followed
+by |of|, then the position of the node is shifted in such a manner that it is
+placed at the distance |node distance| in the specified direction of the given
+direction. The |node distance| is either the distance between the centers of
+the nodes (when the |on grid| option is set to true) or the distance between
+the borders (when the |on grid| option is set to false, which is the default).
+Even though the above code has the same effect as the earlier code, Hagen can
+pass it to his colleagues who will be able to just read and understand it,
+perhaps without even having to see the picture.
\subsection{Adding Labels Next to Nodes}
-Before we have a look at how Hagen can connect the nodes, let us add
-the capacity ``$s \le 3$'' to the bottom node. For this, two
-approaches are possible:
+Before we have a look at how Hagen can connect the nodes, let us add the
+capacity ``$s \le 3$'' to the bottom node. For this, two approaches are
+possible:
+%
\begin{enumerate}
-\item Hagen can just add a new node above the |north| anchor of the
- |semaphore| node.
+ \item Hagen can just add a new node above the |north| anchor of the
+ |semaphore| node.
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -527,17 +511,19 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{tikzpicture}
\end{codeexample}
}
-This is a general approach that will ``always work.''
-
-\item Hagen can use the special |label| option. This option is given
- to a |node| and it causes \emph{another} node to be added next to
- the node where the option is given. Here is the idea: When we
- construct the |semaphore| node, we wish to indicate that we want
- another node with the capacity above it. For this, we use the option
- |label=above:$s\le 3$|. This option is interpreted as follows: We
- want a node above the |semaphore| node and this node should read
- ``$s \le 3$.'' Instead of |above| we could also use things like
- |below left| before the colon or a number like |60|.
+ %
+ This is a general approach that will ``always work''.
+
+ \item Hagen can use the special |label| option. This option is given to a
+ |node| and it causes \emph{another} node to be added next to the node
+ where the option is given. Here is the idea: When we construct the
+ |semaphore| node, we wish to indicate that we want another node with
+ the capacity above it. For this, we use the option
+ |label=above:$s\le 3$|. This option is interpreted as follows: We want
+ a node above the |semaphore| node and this node should read ``$s \le
+ 3$''. Instead of |above| we could also use things like |below left|
+ before the colon or a number like |60|.
+ %
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -554,21 +540,25 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{tikzpicture}
\end{codeexample}
}
- It is also possible to give multiple |label| options, this causes
- multiple labels to be drawn.
+ %
+ It is also possible to give multiple |label| options, this causes
+ multiple labels to be drawn.
+ %
\begin{codeexample}[]
\tikz
\node [circle,draw,label=60:$60^\circ$,label=below:$-90^\circ$] {my circle};
\end{codeexample}
- Hagen is not fully satisfied with the |label| option since the label
- is not red. To achieve this, he has two options: First, he can
- redefine the |every label| style. Second, he can add options to the
- label's node. These options are given following the |label=|, so he
- would write |label=[red]above:$s\le3$|. However, this does not quite
- work since \TeX\ thinks that the |]| closes the whole option list of
- the |semaphore| node. So, Hagen has to add braces and writes
- |label={[red]above:$s\le3$}|. Since this looks a bit ugly, Hagen
- decides to redefine the |every label| style.
+ %
+ Hagen is not fully satisfied with the |label| option since the label
+ is not red. To achieve this, he has two options: First, he can
+ redefine the |every label| style. Second, he can add options to the
+ label's node. These options are given following the |label=|, so he
+ would write |label=[red]above:$s\le3$|. However, this does not quite
+ work since \TeX\ thinks that the |]| closes the whole option list of
+ the |semaphore| node. So, Hagen has to add braces and writes
+ |label={[red]above:$s\le3$}|. Since this looks a bit ugly, Hagen
+ decides to redefine the |every label| style.
+ %
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -588,20 +578,18 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{enumerate}
-
\subsection{Connecting Nodes}
-It is now high time to connect the nodes. Let us start with something
-simple, namely with the straight line from |enter critical| to
-|critical|. We want this line to start at the right side of
-|enter critical| and to end at the left side of |critical|. For
-this, we can use the \emph{anchors} of the nodes. Every node defines a
-whole bunch of anchors that lie on its border or inside it. For
-example, the |center| anchor is at the center of the node, the |west|
-anchor is on the left of the node, and so on. To access the coordinate
-of a node, we use a coordinate that contains the node's name followed
-by a dot, followed by the anchor's name:
-
+It is now high time to connect the nodes. Let us start with something simple,
+namely with the straight line from |enter critical| to |critical|. We want this
+line to start at the right side of |enter critical| and to end at the left side
+of |critical|. For this, we can use the \emph{anchors} of the nodes. Every node
+defines a whole bunch of anchors that lie on its border or inside it. For
+example, the |center| anchor is at the center of the node, the |west| anchor is
+on the left of the node, and so on. To access the coordinate of a node, we use
+a coordinate that contains the node's name followed by a dot, followed by the
+anchor's name:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -619,9 +607,9 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-Next, let us tackle the curve from |waiting| to |enter critical|. This
-can be specified using curves and controls:
-
+Next, let us tackle the curve from |waiting| to |enter critical|. This can be
+specified using curves and controls:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -641,13 +629,13 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-Hagen sees how he can now add all his edges, but the whole process
-seems a but awkward and not very flexible. Again, the code seems to
-obscure the structure of the graphic rather than showing it.
-
-So, let us start improving the code for the edges. First, Hagen can
-leave out the anchors:
+Hagen sees how he can now add all his edges, but the whole process seems a but
+awkward and not very flexible. Again, the code seems to obscure the structure
+of the graphic rather than showing it.
+So, let us start improving the code for the edges. First, Hagen can leave out
+the anchors:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -667,25 +655,22 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-Hagen is a bit surprised that this works. After all, how did
-\tikzname\ know that the line from |enter critical| to |critical|
-should actually start on the borders? Whenever \tikzname\ encounters a
-whole node name as a ``coordinate,'' it tries to ``be smart'' about
-the anchor that it should choose for this node. Depending on what
-happens next, \tikzname\ will choose an anchor that lies on the border
-of the node on a line to the next coordinate or control point. The
-exact rules are a bit complex, but the chosen point will usually be
-correct -- and when it is not, Hagen can still specify the desired
-anchor by hand.
-
-Hagen would now like to simplify the curve operation somehow. It turns
-out that this can be accomplished using a special path operation: the
-|to| operation. This operation takes many options (you can even define
-new ones yourself). One pair of options is useful for Hagen: The pair
-|in| and |out|. These options take angles at which a curve should
-leave or reach the start or target coordinates. Without these options,
-a straight line is drawn:
-
+Hagen is a bit surprised that this works. After all, how did \tikzname\ know
+that the line from |enter critical| to |critical| should actually start on the
+borders? Whenever \tikzname\ encounters a whole node name as a ``coordinate'',
+it tries to ``be smart'' about the anchor that it should choose for this node.
+Depending on what happens next, \tikzname\ will choose an anchor that lies on
+the border of the node on a line to the next coordinate or control point. The
+exact rules are a bit complex, but the chosen point will usually be correct --
+and when it is not, Hagen can still specify the desired anchor by hand.
+
+Hagen would now like to simplify the curve operation somehow. It turns out that
+this can be accomplished using a special path operation: the |to| operation.
+This operation takes many options (you can even define new ones yourself). One
+pair of options is useful for Hagen: The pair |in| and |out|. These options
+take angles at which a curve should leave or reach the start or target
+coordinates. Without these options, a straight line is drawn:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -704,11 +689,10 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-There is another option for the |to| operation, that is even better
-suited to Hagen's problem: The |bend right| option. This option also
-takes an angle, but this angle only specifies the angle by which the
-curve is bent to the right:
-
+There is another option for the |to| operation, that is even better suited to
+Hagen's problem: The |bend right| option. This option also takes an angle, but
+this angle only specifies the angle by which the curve is bent to the right:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -728,17 +712,15 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-It is now time for Hagen to learn about yet another way of specifying
-edges: Using the |edge| path operation. This operation is very similar
-to the |to| operation, but there is one important difference: Like a
-node the edge generated by the |edge| operation is not part of the
-main path, but is added only later. This may not seem very important,
-but it has some nice consequences. For example, every edge can have
-its own arrow tips and its own color and so on and, still, all the
-edges can be given on the same path. This allows Hagen to write the
-following:
-
-
+It is now time for Hagen to learn about yet another way of specifying edges:
+Using the |edge| path operation. This operation is very similar to the |to|
+operation, but there is one important difference: Like a node the edge
+generated by the |edge| operation is not part of the main path, but is added
+only later. This may not seem very important, but it has some nice
+consequences. For example, every edge can have its own arrow tips and its own
+color and so on and, still, all the edges can be given on the same path. This
+allows Hagen to write the following:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -758,13 +740,12 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
\end{codeexample}
}
-Each |edge| caused a new path to be constructed, consisting of a |to|
-between the node |enter critical| and the node following the |edge|
-command.
-
-The finishing touch is to introduce two styles |pre| and |post| and to
-use the |bend angle=45| option to set the bend angle once and for all:
+Each |edge| caused a new path to be constructed, consisting of a |to| between
+the node |enter critical| and the node following the |edge| command.
+The finishing touch is to introduce two styles |pre| and |post| and to use the
+|bend angle=45| option to set the bend angle once and for all:
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -794,17 +775,14 @@ transition/.style={rectangle,draw=black!50,fill=black!20,thick,
}
-
-
\subsection{Adding Labels Next to Lines}
-The next thing that Hagen needs to add is the ``$2$'' at the arcs. For
-this Hagen can use \tikzname's automatic node placement: By adding the
-option |auto|, \tikzname\ will position nodes on curves and lines in
-such a way that they are not on the curve but next to it. Adding
-|swap| will mirror the label with respect to the line. Here is a
-general example:
-
+The next thing that Hagen needs to add is the ``$2$'' at the arcs. For this
+Hagen can use \tikzname's automatic node placement: By adding the option
+|auto|, \tikzname\ will position nodes on curves and lines in such a way that
+they are not on the curve but next to it. Adding |swap| will mirror the label
+with respect to the line. Here is a general example:
+%
{
\begin{codeexample}[]
\begin{tikzpicture}[auto,bend right]
@@ -819,18 +797,16 @@ general example:
\end{codeexample}
}
-What is happening here? The nodes are given somehow inside the |to|
-operation! When this is done, the node is placed on the middle of the
-curve or line created by the |to| operation. The |auto| option then
-causes the node to be moved in such a way that it does not lie on the
-curve, but next to it. In the example we provide even two nodes on
-each |to| operation.
-
-For Hagen that |auto| option is not really necessary since the two
-``2'' labels could also easily be placed ``by hand.'' However, in a
-complicated plot with numerous edges automatic placement can be a
-blessing.
+What is happening here? The nodes are given somehow inside the |to| operation!
+When this is done, the node is placed on the middle of the curve or line
+created by the |to| operation. The |auto| option then causes the node to be
+moved in such a way that it does not lie on the curve, but next to it. In the
+example we provide even two nodes on each |to| operation.
+For Hagen that |auto| option is not really necessary since the two ``2'' labels
+could also easily be placed ``by hand''. However, in a complicated plot with
+numerous edges automatic placement can be a blessing.
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -858,32 +834,27 @@ post/.style={->,shorten >=1pt,>=stealth',semithick}}
}
-
\subsection{Adding the Snaked Line and Multi-Line Text}
-With the node mechanism Hagen can now easily create the two Petri
-nets. What he is unsure of is how he can create the snaked line
-between the nets.
-
-For this he can use a \emph{decoration}.
-To draw the snaked line, Hagen only needs to set the two options
-|decoration=snake| and |decorate| on
-the path. This causes all lines of the path to be replaced by
-snakes. It is also possible to use snakes only in certain parts of a
-path, but Hagen will not need this.
+With the node mechanism Hagen can now easily create the two Petri nets. What he
+is unsure of is how he can create the snaked line between the nets.
+For this he can use a \emph{decoration}. To draw the snaked line, Hagen only
+needs to set the two options |decoration=snake| and |decorate| on the path.
+This causes all lines of the path to be replaced by snakes. It is also possible
+to use snakes only in certain parts of a path, but Hagen will not need this.
+%
\begin{codeexample}[]
\begin{tikzpicture}
\draw [->,decorate,decoration=snake] (0,0) -- (2,0);
\end{tikzpicture}
\end{codeexample}
-Well, that does not look quite right, yet. The problem is that the
-snake happens to end exactly at the position where the arrow
-begins. Fortunately, there is an option that helps here. Also, the
-snake should be a bit smaller, which can be influenced by even more
-options.
-
+Well, that does not look quite right, yet. The problem is that the snake
+happens to end exactly at the position where the arrow begins. Fortunately,
+there is an option that helps here. Also, the snake should be a bit smaller,
+which can be influenced by even more options.
+%
\begin{codeexample}[]
\begin{tikzpicture}
\draw [->,decorate,
@@ -892,11 +863,11 @@ options.
\end{tikzpicture}
\end{codeexample}
-Now Hagen needs to add the text above the snake. This text is a bit
-challenging since it is a multi-line text. Hagen has two options for
-this: First, he can specify an |align=center| and then use the |\\|
-command to enforce the line breaks at the desired positions.
-
+Now Hagen needs to add the text above the snake. This text is a bit challenging
+since it is a multi-line text. Hagen has two options for this: First, he can
+specify an |align=center| and then use the |\\| command to enforce the line
+breaks at the desired positions.
+%
\begin{codeexample}[]
\begin{tikzpicture}
\draw [->,decorate,
@@ -911,10 +882,9 @@ command to enforce the line breaks at the desired positions.
\end{tikzpicture}
\end{codeexample}
-Instead of specifying the line breaks ``by hand,'' Hagen can also
-specify a width for the text and let \TeX\ perform the line breaking
-for him:
-
+Instead of specifying the line breaks ``by hand'', Hagen can also specify a
+width for the text and let \TeX\ perform the line breaking for him:
+%
\begin{codeexample}[]
\begin{tikzpicture}
\draw [->,decorate,
@@ -929,34 +899,31 @@ for him:
\end{codeexample}
-
\subsection{Using Layers: The Background Rectangles}
-Hagen still needs to add the background rectangles. These are a bit
-tricky: Hagen would like to draw the rectangles \emph{after} the Petri
-nets are finished. The reason is that only then can he conveniently
-refer to the coordinates that make up the corners of the
-rectangle. If Hagen draws the rectangle first, then he needs to know
-the exact size of the Petri net -- which he does not.
-
-The solution is to use \emph{layers}. When the background library is
-loaded, Hagen can put parts of his picture inside a scope with the
-|on background layer| option. Then this part of the picture becomes
-part of the layer
-that is given as an argument to this environment. When the
-|{tikzpicture}| environment ends, the layers are put on top of each
-other, starting with the background layer. This causes everything
-drawn on the background layer to be behind the main text.
-
-The next tricky question is, how big should the rectangle be?
-Naturally, Hagen can compute the size ``by hand'' or using some clever
-observations concerning the $x$- and $y$-coordinates of the nodes, but
-it would be nicer to just have \tikzname\ compute a rectangle into
-which all the nodes ``fit.'' For this, the |fit| library can be
-used. It defines the |fit| options, which, when given to a node, causes
-the node to be resized and shifted such that it exactly covers all the
-nodes and coordinates given as parameters to the |fit| option.
-
+Hagen still needs to add the background rectangles. These are a bit tricky:
+Hagen would like to draw the rectangles \emph{after} the Petri nets are
+finished. The reason is that only then can he conveniently refer to the
+coordinates that make up the corners of the rectangle. If Hagen draws the
+rectangle first, then he needs to know the exact size of the Petri net -- which
+he does not.
+
+The solution is to use \emph{layers}. When the background library is loaded,
+Hagen can put parts of his picture inside a scope with the
+|on background layer| option. Then this part of the picture becomes part of the
+layer that is given as an argument to this environment. When the
+|{tikzpicture}| environment ends, the layers are put on top of each other,
+starting with the background layer. This causes everything drawn on the
+background layer to be behind the main text.
+
+The next tricky question is, how big should the rectangle be? Naturally, Hagen
+can compute the size ``by hand'' or using some clever observations concerning
+the $x$- and $y$-coordinates of the nodes, but it would be nicer to just have
+\tikzname\ compute a rectangle into which all the nodes ``fit''. For this, the
+|fit| library can be used. It defines the |fit| options, which, when given to a
+node, causes the node to be resized and shifted such that it exactly covers all
+the nodes and coordinates given as parameters to the |fit| option.
+%
{
\tikzset{place/.style={circle,draw=blue!50,fill=blue!20,thick,
inner sep=0pt,minimum size=6mm},
@@ -989,19 +956,17 @@ post/.style={->,shorten >=1pt,>=stealth',semithick}}
}
-
\subsection{The Complete Code}
-Hagen has now finally put everything together. Only then does he learn
-that there is already a library for drawing Petri nets! It turns out
-that this library mainly provides the same definitions as Hagen
-did. For example, it defines a |place| style in a similar way as Hagen
-did. Adjusting the code so that it uses the library shortens Hagen
-code a bit, as shown in the following.
-
-First, Hagen needs less style definitions, but he still needs to
-specify the colors of places and transitions.
+Hagen has now finally put everything together. Only then does he learn that
+there is already a library for drawing Petri nets! It turns out that this
+library mainly provides the same definitions as Hagen did. For example, it
+defines a |place| style in a similar way as Hagen did. Adjusting the code so
+that it uses the library shortens Hagen code a bit, as shown in the following.
+First, Hagen needs less style definitions, but he still needs to specify the
+colors of places and transitions.
+%
\begin{codeexample}[code only]
\begin{tikzpicture}
[node distance=1.3cm,on grid,>=stealth',bend angle=45,auto,
@@ -1012,9 +977,9 @@ specify the colors of places and transitions.
\end{codeexample}
Now comes the code for the nets:
-
+%
{
-\tikzset{%
+\tikzset{
every place/.style={minimum size=6mm,thick,draw=blue!75,fill=blue!20},
every transition/.style={thick,draw=black!75,fill=black!20},
red place/.style={place,draw=red!75,fill=red!20},
@@ -1049,7 +1014,7 @@ Now comes the code for the nets:
{
\tikzset{
-every place/.style= {minimum size=6mm,thick,draw=blue!75,fill=blue!20},
+every place/.style={minimum size=6mm,thick,draw=blue!75,fill=blue!20},
every transition/.style={thick,draw=black!75,fill=black!20},
red place/.style= {place,draw=red!75,fill=red!20},
every label/.style={red},
@@ -1091,7 +1056,7 @@ every picture/.style={on grid,node distance=1.3cm,>=stealth',bend angle=45,auto}
}
The code for the background and the snake is the following:
-
+%
\begin{codeexample}[code only]
\begin{scope}[on background layer]
\node (r1) [fill=black!10,rounded corners,fit=(w1)(w2)(e1)(e2)(l1)(l2)] {};