使用 tikz-qtree 的句法树中的箭头放置问题

Question

我正在尝试使用 tikz-qtree 包创建语法树图，但在树中放置箭头时遇到了问题。我尝试了几种解决方案，但都没有解决问题。这是我目前正在使用的代码：

\documentclass{article}
\usepackage{tikz}
\usepackage{tikz-qtree}

\usetikzlibrary{tikzmark}

\tikzset{every tree node/.style={align=center,anchor=north}}
\tikzset{edge from parent/.append style={very thick}}

\begin{document}

\begin{tikzpicture}
    \tikzset{level distance=30pt}
    \tikzset{sibling distance=5pt}
    \Tree [.IP  \node(subj){Mary$_1$};
                [.I$'$  \node(head_I){I};
                        [.AgrOP \node(obj){John$_2$};
                             [.AgrO$'$  \node(head-AgrO){AgrO};
                                     [.VP   [.VP \edge[roof]; {\subnode{t1}{t$_1$} entertained \subnode{t2}{t$_2$}} ]
                                            [.PP \edge[roof]; {during his$_2$ vacation} ]]]]]]
    \draw[thick, ->] (t1.south) to[out=-90,in=-90,looseness=1] (subj.south);
    \draw[thick, dashed, ->] (t2.south) to[out=-90,in=-90,looseness=1] (obj.south);
\end{tikzpicture}

\end{document}

当我编译此代码时，连接跟踪节点 t1 和 t2 到其各自前因的箭头位置不正确。

我尝试过使用 tikzmark 库和\tikzmarknode命令，\tikz[remember picture, baseline]但是似乎没有帮助。

有人能帮我找出问题并提出解决方案以正确定位树状图中的箭头吗？

预先感谢您的帮助！

Answer 1

如果您想要使用该tikzmark包，则需要将其添加[remember picture]到您的tikzpicture环境中。然后经过两次编译后，箭头应该来自正确的位置。

但我不会tikzmark为此使用该包，而只是根据 VP 节点的锚点作为起点，并使用calc库根据需要进行调整：

\documentclass{article}
\usepackage[margin=1in]{geometry}
\usepackage{tikz}
\usepackage{tikz-qtree}
\usetikzlibrary{tikzmark}
\usetikzlibrary{calc}


\tikzset{every tree node/.style={align=center,anchor=north}}
\tikzset{edge from parent/.append style={very thick}}

\begin{document}

With \texttt{tikzmark}

\begin{tikzpicture}[remember picture]
    \tikzset{level distance=30pt}
    \tikzset{sibling distance=5pt}
    \Tree [.IP  \node(subj){Mary$_1$};
                [.I$'$  \node(head_I){I};
                        [.AgrOP \node(obj){John$_2$};
                             [.AgrO$'$  \node(head-AgrO){AgrO};
                                     [.VP   [.VP \edge[roof]; {\subnode{t1}{t$_1$} entertained \subnode{t2}{t$_2$}} ]
                                            [.PP \edge[roof]; {during his$_2$ vacation} ]]]]]]
    \draw[thick, ->] (t1.south) to[out=-90,in=-90,looseness=1] (subj.south);
    \draw[thick, dashed, ->] (t2.south) to[out=-90,in=-90,looseness=1] (obj.south);
\end{tikzpicture}

Without \texttt{tikzmark}

\begin{tikzpicture}
    \tikzset{level distance=30pt}
    \tikzset{sibling distance=5pt}
    \Tree [.IP  \node(subj){Mary$_1$};
                [.I$'$  \node(head_I){I};
                        [.AgrOP \node(obj){John$_2$};
                             [.AgrO$'$  \node(head-AgrO){AgrO};
                                     [.VP   [.VP \edge[roof]; \node(VP){$t_1$ entertained t$_2$}; ]
                                            [.PP \edge[roof]; {during his$_2$ vacation} ]]]]]]
    \draw[thick, ->] (VP.south west) to[out=-110,in=-90,looseness=1] (subj.south);
    \draw[thick, dashed, ->] ($(VP.south east)-(.25,0)$) to[out=-85,in=-90,looseness=1] (obj.south);
\end{tikzpicture}


\end{document}

Answer 2

\subnode，如果使用得当，它们会按预期工作。必须是整个画面的一个选项。几乎可以肯定，您只想将其remember picture用于弯曲的箭头。应该像在代码中一样使用 s。overlayremember pictureoverlay\subnode

\documentclass{article}
\usepackage{tikz}
\usepackage{tikz-qtree}

\usetikzlibrary{tikzmark}

\tikzset{every tree node/.style={align=center,anchor=north}}
\tikzset{edge from parent/.append style={very thick}}

\begin{document}
\begin{tikzpicture}[remember picture]
    \tikzset{level distance=30pt}
    \tikzset{sibling distance=5pt}
            \Tree [.IP  \node(subj){Mary$_1$};
                [.I$'$  \node(head_I){I};
                        [.AgrOP \node(obj){John$_2$};
                             [.AgrO$'$  \node(head-AgrO){AgrO};
                                     [.VP   [.VP \edge[roof]; {\subnode{t1}{t$_1$} entertained \subnode{t2}{t$_2$}} ]
                                            [.PP \edge[roof]; {during his$_2$ vacation} ]]]]]]

    \draw[overlay,thick, ->] (t1.south) to[out=-90,in=-90,looseness=1] (subj.south);
    \draw[overlay,thick, dashed, ->] (t2.south) to[out=-90,in=-90,looseness=1] (obj.south);
\end{tikzpicture}
\end{document}