如何在旋转的树中正确对齐 tikz 节点？

Question

我有一个短旋转树，其中一个节点有两个子节点，这两个子节点都有同一个子节点。但是，第三级的共享子节点未正确对齐。我一直在尝试将 above=Xem 用于第三级，但总是有点不对劲。

有没有办法可以自动将其与第一级正确对齐？

\begin{tikzpicture}[level distance=20em,rotate=90,
edge from parent/.style={->,thick,draw=black,line width = 0.5em,shorten >=8pt, shorten <=8pt},
level 1/.style={sibling distance=15em},
level 2/.style={sibling distance=15em},
every node/.style = {shape=rectangle, rounded corners,thick,scale=2, align=center, line width=0.15em,text centered}]]
\node[text width=12em] {\textbf{1st level}}
    child { node {\textbf{2nd level 1}}
        child { node[name=3] {\textbf{3rd level}} } }
    child { node[name=2] {\textbf{2nd level 2}}
        };
\draw[->,thick,draw=black,line width = 0.5em] (2) edge (3);
\end{tikzpicture}

Answer 1

如果你希望 1 级和 3 级之间水平对齐，你可以编写代码

\documentclass{standalone}
\usepackage{tikz}
\usetikzlibrary{calc
    ,positioning}
\begin{document}
    \begin{tikzpicture}[level distance=20em,rotate=90,
        edge from parent/.style={->,thick,draw=black,line width = 0.5em,shorten >=8pt, shorten <=8pt},
        level 1/.style={sibling distance=15em},
        level 2/.style={sibling distance=15em},
        every node/.style = {shape=rectangle, rounded corners,thick,scale=2, align=center, line width=0.15em,text centered}]]
        \node[text width=12em, name=1] {\textbf{1st level}}
        child { node [name=2-1]{\textbf{2nd level 1}}
            %         child { node[name=3] {\textbf{3rd level}} } 
        }
        child { node[name=2-2] {\textbf{2nd level 2}}
        };
        % \draw[->,thick,draw=black,line width = 0.5em] (2-2) edge (3);
        \node [right=20em of $(2-1)!.5!(2-2)$, anchor=center] (3) {\textbf{3rd level}};
        % \node [right=20em of 1|-2-1, anchor=center] (3) {\textbf{3rd level}}; % <-- or
        \draw[->,thick,draw=black,line width = 0.5em] (2-1) edge (3);
        \draw[->,thick,draw=black,line width = 0.5em] (2-2) edge (3);
    \end{tikzpicture}
\end{document}

Answer 2

编辑：

首先，让我清理一下您的代码，以便能够努力找到用纯 绘制的树的解决方案tikz。在删除所有混乱、重复的规范和样式定义中的矛盾之后，它是：

\documentclass[border=3.141592]{standalone}
\usepackage{tikz}

\begin{document}
    \begin{tikzpicture}[
                   grow = east, % <--- tree is not rotate but grow to east!
             arr/.style = {draw, ->,line width=1mm,
                           shorten >=8pt, shorten <=8pt},
edge from parent/.style = {arr},
      every node/.style = {draw, rounded corners, thick, font=\bfseries, anchor=east},
         level distance = 20em,
       sibling distance = 15em,
                        ]
\node   {1st level}
    child { node {2nd level 1}
        child { node[name=3] {3rd level} } }
    child { node[name=2] {2nd level 2}
        };
\draw[arr] (2) edge (3);
    \end{tikzpicture}
\end{document}

然而，它不能解决你的问题，但在使用树搜索解决方案时要明确起点tikz。其他答案中已经给出了这样的解决方案，因此我建议使用 forest包的解决方案：

\documentclass[border=3.141592]{standalone}
\usepackage{forest}
\usetikzlibrary{arrows.meta}

\begin{document}
    \begin{forest}
for tree = {
% nodes 
    draw, rounded corners, 
    minimum height=3ex, 
    minimum width=6em,
    font=\bfseries,
% tree
    grow' = 0,
    parent anchor=east,
    child  anchor=west,
    /tikz/arr/.style = {ultra thick, -{Straight Barb[angle=60:2pt 3]}, % <---
                        shorten >=3pt, shorten <=3pt},  % <---
    edge={arr}, 
    s sep=12mm,
    l sep=18mm,
        }
[1st level 
    [2nd level 2, name=n1]
    [2nd level 1
        [3rd level, name=n2]
        [,phantom]             % <---
    ]
]
\draw[arr]   (n1.east) -- (n2.west);
    \end{forest}
\end{document}