在节点上方绘制箭头以可视化树的旋转

Question

我有一张树形变换的图片，可以直观地看到旋转。我想强调节点上方(Qx)或分支上的箭头=>。代码如下：

\begin{tikzpicture}
    \begin{scope}
    \node{$\Rightarrow$}
    child {node {$Qx$}
        child {node{$\psi$}}
    }
    child {node {$\vartheta$} 
    };
    \end{scope}
    \draw[->] (2.5,-1) -- (3.5,-1);
    \begin{scope}[xshift=6cm]
    \node{$(\overline{Q}x)$}
    child {node {$\Rightarrow$}
        child {node {$\psi$}}
        child {node {$\vartheta$}}
    };
    \end{scope}
\end{tikzpicture}

我希望结果在图片中添加一个红色或蓝色箭头

Answer 1

\documentclass[tikz,border=3mm]{standalone}
\usetikzlibrary{arrows.meta,bending,calc}
\begin{document}
\begin{tikzpicture}[>={Stealth[bend]}]
    \begin{scope}
    \node{$\Rightarrow$}
    child {node (Qx){$Qx$}
        child {node{$\psi$}}
    }
    child {node (theta) {$\vartheta$} 
    };
    \draw[red,->] ($(Qx)+(-1em,0)$) arc[start angle=180,end angle=70,radius=1em];
    \draw[blue,->] ($($(Qx)!0.5!(theta)$)+(150:1em)$) 
        arc[start angle=150,end angle=30,radius=1em];
    \end{scope}
    \draw[->] (2.5,-1) -- (3.5,-1);
    \begin{scope}[xshift=6cm]
    \node{$(\overline{Q}x)$}
    child {node {$\Rightarrow$}
        child {node {$\psi$}}
        child {node {$\vartheta$}}
    };
    \end{scope}
\end{tikzpicture}
\end{document}