Tikzpicture - 绘制图形

Question

我正在尝试使用 tikzpicture 在 latex 中创建此图形：

这是我目前的代码：

\usepackage{tikz}
\begin{tikzpicture}[node distance={15mm}, thick, main/.style = {draw, circle}] 
\node[main] (1) {$_{1,1}$ }; 
\node[main] (2) [below right of=1] {$_{2,1}$ }; 
\node[main] (3) [above right of=2]  {$_{1,2}$ }; 
\node[main] (4) [below right of=3]  {$_{2,2}$ }; 
\draw (1) to [out=45, in=135] (3);
\draw (1) to [out=135,in=45] (3);
\draw (1) to (2); 
\draw (1) to [out=193,in=59,looseness=4] (4);
\draw (2) to (3); 
\draw (2) to [out=180+45, in=135+180] (4);
\draw (2) to [out=180+135,in=180+45] (4);
\draw (3) to (4); 
\end{tikzpicture} 

但这并不是我想要创建的。

我如何添加不与任何现有边交叉的边，或者如何调整曲线的方向或以其他方式创建第一个图形？

注意：应该保留边缘的初始位置，从左下方开始的边缘 1,1 通向右上角的 2,2。

Answer 1

我认为你的问题应该通过操作来处理controls。

这是一个解决方案：

\documentclass{article}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}[node distance={15mm}, thick, main/.style = {draw, circle}] 
\node[main] (1) {$_{1,1}$ }; 
\node[main] (2) [below right of=1] {$_{2,1}$ }; 
\node[main] (3) [above right of=2]  {$_{1,2}$ }; 
\node[main] (4) [below right of=3]  {$_{2,2}$ }; 
\draw (1) to [out=45, in=135] (3);
\draw (1) to [out=135,in=45] (3);
\draw (1) to (2); 
\draw (-.32,-.2) .. controls(-2.1,1.5) and (5.4,2) .. (3.45,-.8);
\draw (2) to (3); 
\draw (2) to [out=180+45, in=135+180] (4);
\draw (2) to [out=180+135,in=180+45] (4);
\draw (3) to (4); 
\end{tikzpicture} 

\end{document}

输出：

您可以根据需要轻松地在线上移动点。\draw (-.32,-.2) .. controls(-2.1,1.5) and (5.4,2) .. (3.45,-.8);起点是(-.32,-.2)，终点是(3.45,-.8)。这些点(-2.1,1.5) and (5.4,2)控制曲线的形状。

Answer 2

无需controls在此处调用（但这是一个很好的解决方案）。只需从边缘开始的角度进行操作即可。在这里，我只是使用\draw (1.-160) to...并玩弄了out值。此外，我还添加了outer sep=0 pt节点定义。

\documentclass[tikz]{standalone}

\begin{document}

    \begin{tikzpicture}[node distance={15mm}, thick, main/.style = {draw, circle,outer sep=0pt}] 
        \node[main] (1) {$_{1,1}$ }; 
        \node[main] (2) [below right of=1] {$_{2,1}$ }; 
        \node[main] (3) [above right of=2]  {$_{1,2}$ }; 
        \node[main] (4) [below right of=3]  {$_{2,2}$ }; 
        \draw (1) to [out=45, in=135] (3);
        \draw (1) to [out=135,in=45] (3);
        \draw (1) to (2); 
        \draw (1.-160) to [out=140,in=59,looseness=2] (4); % <------ HERE
        \draw (2) to (3); 
        \draw (2) to [out=180+45, in=135+180] (4);
        \draw (2) to [out=180+135,in=180+45] (4);
        \draw (3) to (4); 
    \end{tikzpicture}

\end{document}