Tikz pictures inside Tikz pictures: typesetting failing in lattice subgraph with edges

Question

I define Tikz pictures within each other. The typesetting fails in a way that the edges are not drawn properly: the edges are not drawn from the centers of vertices in the lattice subgraph structure, instead on the side of the vertices like below

and the lattice subgraph structure is in 2. MWE while simplified example without the issue in 1. MWE: the issue somehow occurs only when having many tikz environments.

1. MWE draws the edges nicely between the centers of vertices

\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=4pt,minimum size=3pt] 
\draw (0,0)node{};
\draw (1,0)node{};
\draw (0.5,1)node{};
\draw (0,0)--(1,0);
\end{tikzpicture}

2. MWE not drawing the edges nicely between the centers of vertices, why?

\begin{tikzpicture}[scale=1.2]
\tikzstyle{every node}=[draw, circle]
\node(0) {
\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=0pt,minimum size=3pt] 
\draw (0,0)node{};
\draw (1,0)node{};
\draw (0.5,1)node{};
\end{tikzpicture}
};

\node[above =of 0](1){
\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=1pt,minimum size=3pt] 
\draw (0,0)node{} -- (1,0)node{};
\draw (0.5,1)node{};
\end{tikzpicture}
};


\node[above right =of 1](21){
\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=1pt,minimum size=3pt] 
\draw (0,0)node{} -- (1,0)node{} -- (0.5,1)node{};
\end{tikzpicture}
};

\node[above left =of 1](22){
\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=1pt,minimum size=3pt] 
\draw (0,0)node{} -- (0.5,1)node{} -- (1,0)node{};
\end{tikzpicture}
};


\node[above left =of 21](30){
\begin{tikzpicture}
\tikzstyle{every node}=[draw, circle, fill=black, inner sep=1pt,minimum size=3pt] 
\draw (0,0)node{} -- (1,0)node{} -- (0.5,1)node{};
\draw (0,0)node{} -- (0.5,1)node{};
\end{tikzpicture}
};


\draw (0) -- (1);
\draw (1) -- (21);
\draw (1) -- (22);
\draw (21) -- (30);
\draw (22) -- (30);
%\draw (21) -- (31);
%\draw (21) -- (32);
%\draw (21) -- (33);
%\draw (31) -- (41);
%\draw (31) -- (42);
%\draw (32) -- (42);
%\draw (33) -- (41);
%\draw (22) -- (32);

\end{tikzpicture}

where the lattice subgraph picture has the failed typesetting, the edges not drawn between the centers. So

How to draw edges properly from the centers of vertices in the lattice subgraph with many tikz environments?

Perhaps relevant

1. Nesting tikz pictures
2. Joining different TikZ pictures
3. What are most important variables set at the beginning of a tikzpicture? of a scope?

Answer 1

There are several ways of achieving that without nesting tikzpictures. You could for example first draw the five circles as nodes, then draw the dots and lines relative to those circles, and finally draw lines between the circles.

In the code below I define a macro \drawdots that draws the three dots in each circle, for convenience. It takes one argument, which is the name of a node, and has three lines of this form:

\path (#1.center) ++(90:0.7cm) node [dotnode] (#1-top) {};

#1 represents the node name passed to the macro, so (#1.center) is the center anchor of the node. ++(90:0.7cm) means roughly "move the active point to the point that is 0.7cm away from the previous point, at an angle of 90 degrees". At this point a new node is declared with node [dotnode] (#1-top) {};. dotnode is style defined as

dotnode/.style={inner sep=0pt,outer sep=0pt,minimum size=3pt,fill,circle}

so it will create a small circle, filled with black, and that node has the name #1-top.

\documentclass[border=4mm]{standalone} 
\usepackage{tikz}
\usetikzlibrary{positioning}
\tikzset{
dotnode/.style={inner sep=0pt,outer sep=0pt,minimum size=3pt,fill,circle},
bigcircle/.style={draw,circle,minimum size=2cm}
}
\newcommand{\drawdots}[1]{
  \path (#1.center) ++(90:0.7cm) node [dotnode] (#1-top) {};
  \path (#1.center) ++(-30:0.7cm) node [dotnode] (#1-right) {};
  \path (#1.center) ++(210:0.7cm) node [dotnode] (#1-left) {};
}
\begin{document}              
\begin{tikzpicture}
% place circles
\node [bigcircle] (A) {};
\node [bigcircle,above=of A] (B) {};
\node [bigcircle,above right=of B] (C) {};
\node [bigcircle,above left=of B] (D) {};
\node [bigcircle,above right=of D] (E) {};

% draw dots
\foreach \A in {A,...,E}
   \drawdots{\A};

% draw edges between dots
\draw (B-left) -- (B-right);
\draw (C-left) -- (C-right) -- (C-top);
\draw (D-left) -- (D-top) -- (D-right);
\draw (E-left) -- (E-right) -- (E-top) -- (E-left);

% draw edges between circles
\draw (A) -- (B) -- (C) -- (E) -- (D) -- (B);
\end{tikzpicture}
\end{document}

Another option would be to use a pic, an example is in the code below.

\documentclass[border=4mm]{standalone} 
\usepackage{tikz}
\pgfmathsetmacro{\circrad}{0.7}
\tikzset{
dotnode/.style={inner sep=0pt,outer sep=0pt,minimum size=3pt,fill,circle},
pics/dotcircle/.style args={#1#2#3}{
code={
 \node [circle,draw,inner sep=0pt,outer sep=0pt,minimum size=2*\circrad cm] (-circ) at (0,0) {};
 \node [dotnode] (-top) at (90:0.7*\circrad cm) {};
 \node [dotnode] (-right) at (-30:0.7*\circrad cm) {};
 \node [dotnode] (-left) at (210:0.7*\circrad cm) {};
\ifnum #1>0
  \draw (-left) -- (-right);
\fi
\ifnum #2 > 0
   \draw (-right) -- (-top);
\fi
\ifnum #3 > 0
   \draw (-left) -- (-top);
\fi
}}}

\begin{document}              
\begin{tikzpicture}
\pic (A) at (0,0) {dotcircle={000}};
\pic (B) at (0,2) {dotcircle={100}};
\pic (C) at (2,4) {dotcircle={110}};
\pic (D) at (-2,4) {dotcircle={011}};
\pic (E) at (0,6) {dotcircle={111}};

\foreach \A/\B in {A/B,B/C,B/D,D/E,C/E}
  \draw (\A-circ) -- (\B-circ);
\end{tikzpicture}
\end{document}