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如何根据圆中点画正方形（月相）

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如何根据圆中点画正方形（月相）

我想绘制月相并从此代码开始

\documentclass{article}
\usepackage{tikz}
\usepackage{pgfplots}
\newcommand*\circled[1]{\tikz[baseline=(char.base)]{\node[shape=circle,draw,inner sep=2pt,fill=white] (char) {#1};}}
\begin{document}
    \begin{tikzpicture}
        \draw (0cm,0cm) circle(4cm);
        \foreach \x in {0,45,...,360} {
            \filldraw[fill=white] (\x:4cm) circle(0.4cm);
            \filldraw[fill=white] (\x:5cm) circle(0.4cm);
            \draw[fill=black!70] (\x:4cm)-- +(0,0.4cm) arc (90:-90:0.4cm) -- cycle;
            }
        \node[inner sep=0pt] at (0,0)   {\includegraphics[height=5cm]{aarde2}};
        \foreach \x/\xtext in {
            0/\circled{5},
            45/\circled{6},
            90/\circled{7},
            135/\circled{8},
            180/\circled{1},
            225/\circled{2},
            270/\circled{3},
            315/\circled{4}}
            \draw (\x:3.3cm) node {\tiny \xtext};
\end{tikzpicture}
\end{document}

结果是：

在此处输入图片描述

（地球的图片未上传）

我的问题是：如何在白色圆圈周围绘制正方形。由于圆圈的半径为 8 毫米，因此正方形的边长应为 1 厘米。

（白色圆圈的目的是当您站在那个位置时，给月相的真实视图着色。

答案1

这是错误的方式，但无论如何......

\documentclass[tikz,border=5]{standalone}
\colorlet{color 0}{white}
\colorlet{color 1}{black}
\begin{document}
\begin{tikzpicture}
\filldraw [fill=color 0] circle [radius=1.5];
\filldraw [fill=color 1] (90:1.5) arc (90:270:1.5) -- cycle;  
\draw (0, 0) circle [radius=4];
\foreach \phase [count=\i,evaluate={\a=\i*45-45; \j=int(mod(\i-1, 4));
  \ca=int(\i>4); \cb=int(\i<5);}]
    in {New moon, Waxing crescent, First quarter, Waxing gibbous,
        Full moon, Waning gibbous, Last quarter, Waning crescent}{
  \filldraw [fill=color 0] (\a:4) circle [radius=0.5];
  \filldraw [fill=color 1] (\a:4) ++(90:0.5) arc (90:270:0.5) -- cycle;
  \begin{scope}[shift=(\a:6), scale=0.75]
    \fill [gray!50] (-1.125, -1.125) rectangle (1.125, 1.125);
    \fill [fill=color \cb] circle [radius=1];
    \ifcase\j
    \or
      \fill [color \ca] (90:1) arc (45:-45:sqrt 2) arc (-90:90:1) -- cycle;
    \or
      \fill [color \ca] (90:1) arc (90:-90:1) -- cycle;
    \or
      \fill [color \ca] (90:1) arc (135:225:sqrt 2) arc (-90:90:1) -- cycle;
    \fi
    \node [anchor=(\i>4)*180-90, align=center, text width=5em]
      at ({(\i>4)*180+90}:1.125) {\phase};
  \end{scope}
  \node [circle, draw] at (\a:3) {\i};
}
\end{tikzpicture} 
\end{document}

在此处输入图片描述

答案2

更换\circled：

\documentclass{article}
\usepackage{tikz}
\usepackage{pgfplots}
\begin{document}
    \begin{tikzpicture}
        \draw (0cm,0cm) circle(4cm);
        \foreach \x in {0,45,...,360} {
            \filldraw[fill=white] (\x:4cm) circle(0.4cm);
            \filldraw[fill=white] (\x:5cm) circle(0.4cm);
            \draw (\x:5cm) +(-.5cm,-.5cm) rectangle +(.5cm,.5cm);
            \draw[fill=black!70] (\x:4cm)-- +(0,0.4cm) arc (90:-90:0.4cm) -- cycle;
            }
        \node[inner sep=0pt] at (0,0)   {\includegraphics[height=5cm]{aarde2}};
        \foreach \x/\xtext in {
            0/5,
            45/6,
            90/7,
            135/8,
            180/1,
            225/2,
            270/3,
            315/4}
            \draw (\x:3.3cm) node[shape=circle,draw,inner sep=2pt,fill=white] {\tiny \xtext};
\end{tikzpicture}
\end{document}

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