如何用 Tikz 绘制星形

Question

如何使用 Tikz 绘制星形，如下图所示

Answer 1

一个选项；使用重心坐标系来定位节点“G”：

\documentclass{article}
\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
\draw[dotted]
  (0,0) coordinate (A) --
  (4,1) coordinate (B) --
  (4.5,2) coordinate (C) -- 
  (3.8,3) coordinate (D) --
  (1.6,4) coordinate (E) --
  (-1,1.5) coordinate (F) --
  cycle;
\draw[thick] 
  (B) -- (D) -- (F) -- cycle;
\draw[dashed] 
  (A) -- (C) -- (E) -- cycle;
\foreach \Coor/\Texto/\Pos in 
  {A/q/below,
  B/b/below,
  C/r/right,
  D/c/right,
  E/p/above,
  F/a/left%
  }
  \node[circle,draw,inner sep=1.5pt,fill=white,label={\Pos:$\Texto$}] 
  at (\Coor) {};
  \node[fill,circle,inner sep=1.5pt,label={right:$G$}] 
  at (barycentric cs:A=0.5,B=0.5,C=0.5,D=0.5,E=0.5,F=0.5) {};  
\end{tikzpicture}

\end{document}

Answer 2

仅用于 PSTricks 的打字练习。该点G是最外层多边形的质心。

\documentclass[pstricks,border=24pt,12pt]{standalone}
\usepackage{pst-eucl}

\begin{document}
\begin{pspicture}[showgrid=false](6,6)
    \pstGeonode[PosAngle={180,90,45,0,-45,-135},CurveType=polygon,linestyle=dotted,dotsep=0.4pt]
        (0,3){a}
        (3,6){p}        
        (5,5){c}            
        (6,3){r}    
        (5.5,1){b}
        (1,0){q}
    \nodexn{(a)+(b)+(c)+(p)+(q)+(r)}{g}
    \pstGeonode(!\psGetNodeCenter{g} g.x 6 div g.y 6 div){G}
    \pspolygon(a)(b)(c)
    \pspolygon[linestyle=dashed](p)(q)(r)
    \foreach \pt in {a,b,c,p,q,r}{\psset{fillcolor=white,fillstyle=solid}\pscircle(\pt){2pt}}
\end{pspicture}
\end{document}