tikz 覆盖层内的 Tikz 图形

Question

我想在幻灯片中创建一个标注。我不是这方面的专家tikz，但我在网上找到了一些东西。

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{shapes,positioning,calc,shadows,decorations.pathmorphing,decorations.pathreplacing,tikzmark}
\newcommand{\tikzmarkinside}[1]{\tikz[overlay,remember picture,baseline=-0.5ex] \node (#1) {};}
\begin{document}
 \begin{frame}
 \begin{itemize}
  \item a\tikzmarkinside{first}\pause
  \item b\pause
  \item c\pause
 \end{itemize}

\tikz[remember picture, overlay]\node[align=center, fill=cyan!20,opacity=0.85, text width=4.2cm, rounded corners,
  draw,rectangle callout,anchor=pointer,callout absolute pointer=(first.south),
      below right= 1 and 1]
  at (first) {
   \begin{minipage}[t][2cm][t]{4cm}
    \begin{tikzpicture}
     \draw [fill=orange] (1,1) rectangle (2,2);
    \end{tikzpicture}
    \end{minipage}
  };
 \end{frame}
\end{document}

这里有两个问题 1) 标注内部有一个矩形，但它有圆角，就像是从标注形状继承下来的一样。我希望有“方形”角 2) 这种定义\tikzmarkinside有效，但可能不太优雅

你能帮助我吗？

附言：我知道我可以使用\includegraphics并包含我的矩形的预编译图像，但我想一次性完成。

Answer 1

您应该避免嵌套 Tikz 图片。相反，您可以在同一个 () 图片中绘制标注和矩形overlay。这也可以解决圆角问题。

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{shapes,positioning,calc,shadows,decorations.pathmorphing,decorations.pathreplacing,tikzmark}
\newcommand{\tikzmarkinside}[1]{\tikz[overlay,remember picture,baseline=-0.5ex] \node (#1) {};}
\begin{document}
\begin{frame}
  \begin{itemize}
  \item a\tikzmarkinside{first}\pause
  \item b\pause
  \item c\pause
  \end{itemize}

  \begin{tikzpicture}[remember picture, overlay]
    \node[align=center, fill=cyan!20,opacity=0.85, text width=4.2cm, rounded corners,
    draw,rectangle callout,anchor=pointer,callout absolute pointer=(first.south),
    below right= 1 and 1,
    minimum height=5em]
    (TheBubble) at (first) {};
    \draw[fill=orange] ($(TheBubble.north west)+(0.2,-0.2)$) rectangle +(1,-1);
  \end{tikzpicture}
\end{frame}
\end{document}

编辑

如果标注内部的结构更复杂，我会使用示波器将其与其余部分分开。示波器内的参考点是标注的左下角。

\begin{tikzpicture}[remember picture, overlay]
    \node[align=center, fill=cyan!20,opacity=0.85, text width=4.2cm, rounded corners,
    draw,rectangle callout,anchor=pointer,callout absolute pointer=(first.south),
    below right= 1 and 1,
    minimum height=7em]
    (TheBubble) at (first) {text inside the callout. It behaves as normal text.
      \begin{itemize}
      \item Test
      \item New test
      \end{itemize}
    };
    %\draw[fill=orange] ($(TheBubble.north west)+(0.2,-0.2)$) rectangle +(1,-1);
    \begin{scope}[shift={($(TheBubble.south west) +(0.2,0.2)$)}]
      \draw[fill=orange] (0,1) rectangle +(1,1);
      \draw[->] (2,0) -- +(0,2) node[left]{$y$};
      \draw[->] (2,0) -- +(1.5,0) node[right]{$x$};
      \draw[smooth,xshift=2cm] plot coordinates {(0,0)(0.5,1)(1,1.5)(1.5,0.5)};
    \end{scope}
  \end{tikzpicture}