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自動繪製圓弧上不同形狀節點之間的路徑

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自動繪製圓弧上不同形狀節點之間的路徑

我有一個圖像，我想在節點之間繪製箭頭，其中箭頭全部「在同一個圓上」。我可以手動實現我想要的目標，如下所示：

\documentclass{standalone}

\usepackage{tikz}
\usetikzlibrary{shapes}
\begin{document}
\begin{tikzpicture}[ultra thick, -stealth]
  \node[circle,fill] (a) at (0: 1) {};
  \node[rectangle,minimum width=1cm,fill](b) at (120: 1) {};
  \node[rectangle,minimum height=1cm,fill](c) at (240: 1) {};
  \draw[dashed] (85: 1) arc (85: 30: 1) ;
  \draw (330:1) arc (330: 280:1) ;
  \draw[dashed] (200:1) arc (200: 140:1);
\end{tikzpicture}
\end{document}

但如果我的節點有不同的形狀和大小，我必須手動找到可用的座標。我真正想做的是找到節點的邊緣與圓相交的位置，並使用這些邊緣繪製圓弧。有沒有一種自動的方法來做到這一點？這個答案是一個部分解決方案，但似乎我仍然必須shorten手動選擇弧度和長度...

實際用例是節點將包含不同寬高比的圖片。我使用一些形狀不合適的節點來近似解決這個問題。

答案1

海科·奧伯迪克統治！ --

https://tex.stackexchange.com/a/250270/197451

在此輸入影像描述

\documentclass{article}

\usepackage{tikz}
\usetikzlibrary{bending}

\begin{document}
    \begin{tikzpicture}[
    ->,   
    thick,
    main node/.style={circle, fill=blue!20, draw},
    ]
    \newcommand*{\MainNum}{5}
    \newcommand*{\MainRadius}{1.5cm} 
    \newcommand*{\MainStartAngle}{90}
    
    % Print main nodes, node names: p1, p2, ...
    \path
    (0, 0) coordinate (M)
    \foreach \t [count=\i] in {A, Hello\\World, 3, foobar, $\cdot$} {
        +({\i-1)*360/\MainNum + \MainStartAngle}:\MainRadius)
        node[main node, align=center] (p\i) {\t}
    }
    ;  
    
    % Calculate the angle between the equal sides of the triangle
    % with side length \MainRadius, \MainRadius and radius of circle node
    % Result is stored in \p1-angle, \p2-angle, ...
    \foreach \i in {1, ..., \MainNum} {
        \pgfextracty{\dimen0 }{\pgfpointanchor{p\i}{north}} 
        \pgfextracty{\dimen2 }{\pgfpointanchor{p\i}{center}}
        \dimen0=\dimexpr\dimen2 - \dimen0\relax 
        \ifdim\dimen0<0pt \dimen0 = -\dimen0 \fi
        \pgfmathparse{2*asin(\the\dimen0/\MainRadius/2)}
        \global\expandafter\let\csname p\i-angle\endcsname\pgfmathresult
    }
    
    % Draw the arrow arcs
    \foreach \i [evaluate=\i as \nexti using {int(mod(\i, \MainNum)+1}]
    in {1, ..., \MainNum} {  
        \pgfmathsetmacro\StartAngle{   
            (\i-1)*360/\MainNum + \MainStartAngle
            + \csname p\i-angle\endcsname
        }
        \pgfmathsetmacro\EndAngle{
            (\nexti-1)*360/\MainNum + \MainStartAngle
            - \csname p\nexti-angle\endcsname
        }
        \ifdim\EndAngle pt < \StartAngle pt
        \pgfmathsetmacro\EndAngle{\EndAngle + 360}
        \fi
        \draw
        (M) ++(\StartAngle:\MainRadius)
        arc[start angle=\StartAngle, end angle=\EndAngle, radius=\MainRadius]
        ;
    }
    \end{tikzpicture}
\end{document}

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