
% pdflatex example1.tex
% pdf2svg example1.pdf ../files/example1.svg

\documentclass[preview,margin=2mm,varwidth,crop]{standalone}
\usepackage{tikz}
\usetikzlibrary {graphs, graphs.standard}

\begin{document}

\begin{tikzpicture}[scale=0.6]
\coordinate (P1) at (0, 2);
\coordinate (P2) at (3, 4);
\coordinate (P3) at (3, 0);
\coordinate (P4) at (6, 2);
\draw[darkgray,line width=2.5mm,line cap=round]
    (P1) -- (P2)
    (P2) -- (P4)
    (P4) -- (P3)
    (P3) -- (P1)
    (P2) -- (P3);
\draw[white,line width=0.2mm,dash pattern=on 1mm off 1.2mm,dash phase=0.7mm]
    (P1) -- (P2)
    (P2) -- (P4)
    (P4) -- (P3)
    (P3) -- (P1)
    (P2) -- (P3);
\node[circle,draw,fill=white] at (P1) {1};
\node[circle,draw,fill=white] at (P2) {2};
\node[circle,draw,fill=white] at (P3) {3};
\node[circle,draw,fill=white] at (P4) {4};
\end{tikzpicture}

\end{document}

