[Tex/LaTex] Tikz-Connecting nodes with multiple lines

blockdiagramsnodespositioningtikz-pgf

I am trying to reproduce the following image I made in "Power point".

enter image description here

Although, there is no difficulty in designing the boxes, I find it rather hard to properly position the red and black lines. One solution is to use pure coordinates, but I think that there must be an easiest way to do it, since I have defined nodes.

My code is

    \documentclass{standalone}
    \usepackage{tikz}
    \usetikzlibrary{positioning}

    \begin{document}

    \begin{tikzpicture}

    \tikzstyle{blockYellow}=[top color=white, bottom color=yellow!60, draw=yellow!90!black!100, minimum size=1cm, rounded corners]
    \tikzstyle{blockBrown}=[top color=white, bottom color=brown!60, draw=brown!90!black!100, minimum size=1cm, rounded corners]
    \tikzstyle{blockBlack}=[top color=white, bottom color=black!60, draw=black!90!black!100, minimum width=1cm, minimum height=5cm, rounded corners]
    \tikzstyle{blockBlue}=[top color=white, bottom color=blue!60, draw=blue!90!black!100, minimum size=1cm, rounded corners]

    \pgfdeclarelayer{background}
    \pgfsetlayers{background,main}

  %PreAmp
 \node[blockYellow] (PreAmp) {\eng{(Pre)Amp}};
 %Detectors
 \node [blockBrown, left of=PreAmp, node distance=3.5cm, anchor=east] (E2) {$E_2$};
 \node [blockBrown, above of=E2, node distance=2cm] (E1) {$E_1$};
 \node [blockBrown, below of=E2, node distance=2cm] (E3) {$E_3$};
 \node [blockBrown, above of=PreAmp, node distance=3.5cm] (DE2) {$\Delta E_2$};
 \node [blockBrown, left of=DE2, node distance=2cm] (DE1) {$\Delta E_1$};
 \node [blockBrown, right of=DE2, node distance=2cm] (DE3) {$\Delta E_3$};
 %ADC
 \node [blockBlack, right of=PreAmp, node distance=10cm] (ADC) {\textcolor{white}{$ADC$}};
 %Disc
 \node [blockBlue, below of=PreAmp, node distance=5cm] (Disc) {$Discriminator$};
 %FIFO
 \node [blockBlue, right of=Disc, node distance=5cm] (FIFO) {$FIFO$};
 %DGG
 \node [blockBlue, below of=ADC, node distance=5cm] (DGG) {$DGG$};
 %cables
 \draw[red,very thick] (PreAmp)--(Disc);
 %\draw[red,very thick] (PreAmp.north)--(Disc.north);
 \draw[red,very thick] (Disc)--(FIFO);
 \draw[red,very thick] (FIFO)--(DGG);
 \draw[red,very thick] (DGG)--(ADC);
 \draw[very thick] (DE2)--(PreAmp);
 \draw[red, very thick] (E2)--(PreAmp);
 \draw[red, very thick] ($(PreAmp.south west)!0.33!(PreAmp.south east)$)coordinate (a)--(a|-Disc.north);
 \draw[red, very thick] ($(PreAmp.south west)!0.66!(PreAmp.south east)$)coordinate (b)--(b|-Disc.north);
 %\draw[red, very thick] ($(Disc.north east)!0.33!(Disc.south east)$)coordinate (c)--(c|-FIFO.west);
 \draw[red, very thick] ($(Disc.north east)!0.33!(Disc.south east)$) -- ($(FIFO.north west)!0.33!(FIFO.south west)$);
 \draw[red, very thick] ($(Disc.north east)!0.66!(Disc.south east)$) -- ($(FIFO.north west)!0.66!(FIFO.south west)$);
 \draw[very thick] ($(PreAmp.north east)!1/7!(PreAmp.south east)$)--+(0:8.525cm);%(c|-[]ADC.north);%-- ($(ADC.north west)!0.166!(ADC.south west)$);
 \draw[very thick] ($(PreAmp.north east)!2/7!(PreAmp.south east)$)--+(0:8.525cm);
 \draw[very thick] ($(PreAmp.north east)!3/7!(PreAmp.south east)$)--+(0:8.525cm);
 \draw[red, very thick] ($(PreAmp.north east)!4/7!(PreAmp.south east)$)--+(0:8.525cm);
 \draw[red, very thick] ($(PreAmp.north east)!5/7!(PreAmp.south east)$)--+(0:8.525cm);
 \draw[red, very thick] ($(PreAmp.north east)!6/7!(PreAmp.south east)$)--+(0:8.525cm);
    \end{tikzpicture}
    \end{document}

and my output is

enter image description here

How to draw the lines using nodes instead of coordinates? I am thinking something like

\draw[very thick] (PreAmp.south/3)--(Disc.north/3);

i.e. not having to define the line's length, just to connect the two nodes.

Straight Lines

EDIT After @ClaudioFiandrino 's suggestion on a personal chat I used the following code to connect the nodes.

\draw ($(PreAmp.south west)!0.33!(PreAmp.south east)$)coordinate (a)--(a|-Disc.north);

Although this works for the vertical lines, I can't get it to work for the horizontal one because when I use

\draw ($(Disc.north east)!0.33!(Disc.south east)$)coordinate (c)--(c|-FIFO.west);

I get a vertical line as shown below in the black line. I insist in using calc and |- because the nodes in this picture don't have the same dimensions.

enter image description here

"Curved" Lines

The only way to reproduce the curved lines is to use relative coordinates, but I feel that there must a more convenient way.

So I used

%curved cables
 \draw[red, very thick] (E1.east)-- ++(1.3cm,0) -- ++(0,-1.5cm)-- ++(1.3cm,0);%($(PreAmp.north west)!1/3!(PreAmp.south west)$);
 \draw[red, very thick] (E3.east)-- ++(1.3cm,0) -- ++(0,1.5cm)-- ++(1.3cm,0);
 \draw[very thick] (DE3.south)-- ++(0,-1.1cm) -- ++(-1.5cm,0)-- ++(0,-1.15cm);
 \draw[very thick] (DE1.south)-- ++(0,-1.1cm) -- ++(1.5cm,0)-- ++(0,-1.15cm);

and the output is

enter image description here

Best Answer

You can use the calc-library to set the connection-points for your lines. It's a simple approach which should be enough in the most situations. A small MWE:

\documentclass[tikz, border=5mm]{standalone}
\usetikzlibrary{calc}

\begin{document}
 \begin{tikzpicture}
  \node at (0,0) [draw, rectangle, minimum height=2cm, minimum width=.5cm] (mynode) {};
  \foreach \y in {-.75,-.5,-.25}{
    \draw [red, ->] (-1,\y) -- ($(mynode.west) +(0,\y)$);
  }
  % ... more lines
 \end{tikzpicture}
\end{document}

rendered image

Is this information satisfying enough for you or do you need more input?

Edit: Usage of percentual values depending on nodes The following code uses the calc-library to position the line-connectors on an percentual value of the node's edge. (Assumed this from your answer)

The nodes need the same width/height to make use of this!

\documentclass[tikz, border=5mm]{standalone}
\usetikzlibrary{calc, positioning}

\begin{document}
 \begin{tikzpicture}
  \node [draw, rectangle, minimum width=3cm, minimum height=1cm] (PreAmp) {PreAmp};
  \node [draw, rectangle, minimum height=1cm, right=2cm of PreAmp] (ADC) {ADC};
  \node [draw, rectangle, minimum width=3cm, below=1cm of PreAmp] (Disc) {Discriminator};
  \foreach \x in {.25,.5,.75} {
   \draw ($(PreAmp.south west)!\x!(PreAmp.south east)$) -- ($(Disc.north west)!\x!(Disc.north east)$);
   \draw ($(PreAmp.north east)!\x!(PreAmp.south east)$) -- ($(ADC.north west)!\x!(ADC.south west)$);
  }
 \end{tikzpicture}
\end{document}

rendered image

To show the two solutions side-by-side: Relative positioning (1 point) vs. percentual positioning (edge)

Blue: percentual positioning on node's edge (the nodes need the same width/height)
Red: relative positioning using node's anchors (the node's centers need to be on one axis to make this work)

Code:

\documentclass[tikz, border=5mm]{standalone}
\usetikzlibrary{calc, positioning}

\begin{document}
 \begin{tikzpicture}
  \node [draw, rectangle, minimum width=3cm, minimum height=1cm] (PreAmp) {PreAmp};
  \node [draw, rectangle, minimum height=1cm, right=2cm of PreAmp] (ADC) {ADC};
  \node [draw, rectangle, minimum width=3cm, below=1cm of PreAmp] (Disc) {Discriminator};
  \foreach \x in {.25,.5,.75} {
   % Percentual on node edge
   \draw [ultra thick, blue] ($(PreAmp.south west)!\x!(PreAmp.south east)$) -- ($(Disc.north west)!\x!(Disc.north east)$);
   \draw [ultra thick, blue] ($(PreAmp.north east)!\x!(PreAmp.south east)$) -- ($(ADC.north west)!\x!(ADC.south west)$);
  }
  \foreach \x in {-.25,0,.25} {
   % Relative to one point
   \draw [red] ($(PreAmp.south) +(\x,0)$) -- ($(Disc.north) +(\x,0)$);
   \draw [red] ($(PreAmp.east)  +(0,\x)$) -- ($(ADC.west) +(0,\x)$);
  }
 \end{tikzpicture}
\end{document}

rendered image

Related Solutions

[Tex/LaTex] Connecting nodes with brace in TikZ

An automatic solution:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{calc,shapes.arrows,decorations.pathreplacing,shadows}

% list of keys
\pgfkeys{/tikz/.cd,
  arrow color/.store in=\arrowcol,
  arrow color=green!80!blue,
  items distance/.store in=\itemdistance,
  items distance=3cm,
  border color/.store in=\bordercol,
  border color=green!80!black,
  fill color/.store in=\fillcol,
  fill color=green!80!lime!20,
  brace color/.store in=\bracecol,
  brace color=green!80!blue,
  brace distance/.store in=\bracedistance,
  brace distance=5pt,
}

% list of styles
\tikzset{my arrow/.style={
    single arrow, draw, minimum height=0.5cm,
    minimum width=0.05cm,
    single arrow head extend=0.1cm
  },
  module/.style={
    rounded corners,
    draw=\bordercol,
    fill=\fillcol,
    minimum height=1cm,
    minimum width=1.5cm,
    general shadow={shadow yshift=-.4ex,opacity=.4, fill=black!50, every shadow}, 
  },
  brace/.style={
    decoration={brace,raise=\bracedistance,amplitude=0.75em},
    decorate,
    draw=\bracecol,
    very thick,    
  }
}

% code able to reproduce arrows between two modules     
\newcommand{\guparrow}{
node[my arrow,top color=\arrowcol!10,bottom color=\arrowcol,midway] {}
}

% braceddiagram:
% #1 options <optional argument>,
% #2 list of items <mandatory>,
% #3 brace comment <mandatory> 
\newcommand{\braceddiagram}[3][]{
  \begin{tikzpicture}[#1]% here we can pass the options for customization
     % counting all the items to be displayed
     \foreach \items [count=\xi] in {#2}{\global\let\maxnumitem\xi}

     % foreach item in the list we are going to compute the distance it should 
     % be placed;
     % then we put the item in a node with the module style: it also gets a 
     % name in the form <module><num-module>
     \foreach \items [count=\xi] in {#2}{%
       \path let 
         \n1={0+\xi*\itemdistance} in
         node[module] (module\xi) at +(\n1,0) {\items};
     }
     % when all items are located we can put the arrows in between: 
     % for this we draw an imaginary path and we put the arrow between nodes; 
     % the path starts from the module on the left and ends in the 
     % subsequent module: we should compute analytically the start and end modules
     \foreach \items [count=\xi] in {#2}{%
       \pgfmathtruncatemacro{\xj}{mod(\xi, \maxnumitem) + 1)}
       \ifnum\xi<\maxnumitem % to not have a path starting from the last module 
                             % directed to the first one
         \path (module\xj) -- (module\xi) \guparrow;
       \fi
     }

     % at the end we draw the brace with the comment
     \draw[brace] (module1.north west)--(module\maxnumitem.north east)
      node[above=3*\bracedistance, midway]{#3};

  \end{tikzpicture}
}


\begin{document}

\braceddiagram[brace distance=4pt]{Bla, Bla, Bla}{Some comment}

\vspace{1cm}

\tikzset{my style for the diagram/.style={
    brace distance=6pt,
    brace color=violet!60!magenta,
    fill color=violet!60!magenta!30,
    border color=violet!60!magenta,
    arrow color=violet!60!magenta,
  }
}

\braceddiagram[my style for the diagram]{Bla, Bla, Bla, Bla}{Some other comment}

\end{document}

The result:

enter image description here

Some notes on the code

The basic command to be used is:

\braceddiagram[<options>]{<list of items>}{<comment above brace>}

In the <list of items> one should insert a comma separated list: each of them will be placed in an horizontal fashion and the distance between two of them is characterized by the key items distance (initial value 3cm). Beware: too many items won't probably fit the page, so one can either reduce the distance of the items or scale the diagram.

Scaling the diagram consists of introducing the standard two options scale=<factor> and transform shape. For example:

\braceddiagram[scale=0.75,transform shape]{Bla, Bla, Bla, Bla}{Some other comment}

In the <options> argument, optional, it is possible to introduce usual TikZ options (as did before) as well as the specific keys of the diagram. When one needs to customize several keys, it is better to create a new style:

\tikzset{my style for the diagram/.style={
    brace distance=6pt,
    brace color=violet!60!magenta,
    fill color=violet!60!magenta!30,
    border color=violet!60!magenta,
    arrow color=violet!60!magenta,
  }
}

to be passed to the diagram:

\braceddiagram[my style for the diagram,thick,scale=0.75,transform shape]{Bla, Bla, Bla, Bla}{Some other comment}

[Tex/LaTex] How to define the default vertical distance between nodes

I don't really get the question so I hope this is what you wanted. If you include a full document (such that we copy paste and see the problem on our systems) things are much more easier.

Here, you can change the default setting within a scope but your block style had a node distance which was resetting every time it is issued. I've made it 2mm such that we can see the difference easier.

\documentclass[tikz]{standalone}
\usetikzlibrary{arrows,shapes.geometric,positioning}

\begin{document}
\begin{tikzpicture}[decision/.style={diamond, draw, text width=4.5em, text badly centered, node distance=3.5cm, inner sep=0pt},
                    block/.style   ={rectangle, draw, text width=6em, text centered, rounded corners, minimum height=4em, minimum height=2em},
                    cloud/.style   ={draw, ellipse, minimum height=2em},
                    line/.style    ={draw,-latex'},
                    node distance = 1cm, 
                    auto]
    \node [block] (1st) {1st};
    \node [block, right= of 1st]  (2nd1) {2nd1};
\begin{scope}[node distance=2mm and 10mm]%Here we change it for everything inside this scope
    \node [block, above= of 2nd1] (2nd2) {2nd2};
    \node [block, below= of 2nd1] (2nd3) {2nd3};
    \node [block, right= of 2nd1] (3rd1) {3rd1};
    \node [block, above= of 3rd1] (3rd2) {3rd2};
    \node [block, above= of 3rd2] (3rd3) {3rd3};
\end{scope}
    \node [block, below= of 3rd1] (3rd4) {3rd4};
    \node [block, below= of 3rd4] (3rd5) {3rd5};

    \path [line] (1st) -- (2nd1);
    \path [line] (2nd1) -- (2nd2);
    \path [line] (2nd1) -- (2nd3);
    \path [line] (2nd2) -- (3rd3);
    \path [line] (2nd1) -- (3rd1);
    \path [line] (1st) -- (2nd1);
\end{tikzpicture}
\end{document}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] Connecting nodes with brace in TikZ

[Tex/LaTex] How to define the default vertical distance between nodes

Related Question