[Tex/LaTex] Draw a railway network in Tikz

diagramstikz-pgf

I need to make several diagrams of a railway network, each of them representing different scenarios. Here is an ugly example of what I want:
enter image description here
And here my first attempt to reproduce it:

As you can see, I am perfectly capable of reproducing the scenario in Tikz, but I would have to do lots of different scenarios. Can someone help me improve my code? What I need is a quick and "automatized" way of delimiting the rails (in black), the rest I can do it. What I find difficult is creating the paths with the same angles when I try to change from one side to the other and to create the end lines that represent a contact. Moreover, different scenarios have different ways of connecting both sides.

MWE:

\documentclass[tikz,border=5pt]{standalone}

\begin{document}

\usetikzlibrary{shapes}
\tikzstyle{rail}=[very thick]       % m19
\begin{tikzpicture}


\draw [rail] (0,0) -- (2,0)  -- (3.5,3.8);
\draw [rail] (3.2,3.8) -- (3.8,3.8);

\draw [rail] (2.5,0) -- (5.5,0);
\draw [rail] (2.5,-0.3) -- (2.5,0.3);
\draw [rail] (5.5,-0.3) -- (5.5,0.3);

\draw [rail] (4.5,3.8) -- (6,0) -- (10.5,0);
\draw [rail] (4.2,3.8) -- (4.8,3.8);
\draw [rail] (10.5,-0.3) -- (10.5,0.3);

\node [rectangle,draw,fill=green, minimum width=1cm, minimum height=1cm] (train) at (1.5,4) {TTX2};

\draw [rail] (train) -- (9.3,4) -- (11,0) -- (13,0);
\draw [rail] (13,-0.3) -- (13,0.3);

\draw [rail](10,4) --(13,4);
\node [diamond,draw,fill=yellow] at (7.5,4) {};

\node [draw] (zone2) at (9,5.5) {Zone 2};
\draw [rail] (zone2) -- (11,5.5) -- (11.6,4.2);
\draw [rail] (11.3,4.2) -- (11.9,4.2);


\end{tikzpicture}

\end{document}

Best Answer

I defined two LaTeX macros for the arrow-like endings:

\newcommand*{\railWEend}{+ (-.3,0) -- + (.3,0) + (0,0)}
\newcommand*{\railNSend}{+ (0,.3) -- + (0,-.3) + (0,0)}

They essentially draw a .6cm long line in either north-south or west-east direction. See the full example below how they are used.

The accident diamond is put directly in the path that draws the main line. Notice the pos=.75 key. The decorations.pathreplacing library is used for the brace.

Code

\documentclass[tikz,border=5pt]{standalone}

\usetikzlibrary{shapes,arrows,decorations.pathreplacing}

\tikzstyle{rail}=[very thick]
\tikzstyle{accident}=[diamond,draw,fill=yellow,thin]

\newcommand*{\railWEend}{+ (-.3,0) -- + (.3,0) + (0,0)}
\newcommand*{\railNSend}{+ (0,.3) -- + (0,-.3) + (0,0)}

\begin{document}

\begin{tikzpicture}
\draw [rail] (0,0) -- (2,0)  -- (3.5,3.8) \railWEend;

\draw [rail] (2.5,0) \railNSend -- (5.5,0) \railNSend;

\draw [rail] (4.5,3.8) \railWEend -- (6,0) -- (10.5,0) \railNSend;

\draw [decoration=brace,decorate,thick,yshift=5mm] (6,0) -- (10.5,0) node [pos=.5,above=1mm] {Maintenance zone};

\node [rectangle,draw,fill=green, minimum width=1cm, minimum height=1cm] (train) at (1.5,4) {TTX2};

\draw [rail] (train) -- node [accident,pos=.75] (acc1) {} (9.3,4) -- (11,0) -- (13,0) \railNSend;

\draw [rail](10,4) --(13,4);

\node [draw] (zone2) at (9,5.5) {Zone 2};
\draw [rail] (zone2) -- (11,5.5) -- (11.6,4.2) \railWEend;

\draw [-triangle 45,green!50!black,line width=2.5\pgflinewidth] (train) -- (acc1);

\end{tikzpicture}
\end{document}

Output

Output of code

Further annotations

I myself tried to write my own macro to design a railway network in TikZ (especially signals).
I defined a few commands and lengths that save distances or auxiliary values. I had different macros for the base of a signal (that is the same for every signal), for the top part and its name that appears near the base.

I quickly gave up because when it comes to complicated signals that have optional information (speed, direction, …) the code would have become very complex. There also already exist shapes/templates for WYSIWYG solutions like Microsoft's Visio.

I would advise you to define rules (or derive them for your technical sector of work), to follow them and use as few as possible absolute coordinates.

Related Solutions

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\begin{document}
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\end{tikzpicture}

\end{document}

Here's the result:

rotated ellipse

(the arrow got clipped, but you can see where it lies)

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    \node [block, above= of 3rd2] (3rd3) {3rd3};
\end{scope}
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    \path [line] (1st) -- (2nd1);
    \path [line] (2nd1) -- (2nd2);
    \path [line] (2nd1) -- (2nd3);
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\end{document}

enter image description here