删除 TikZ 中结束贝塞尔曲线的箭头前不需要的间隙

Question

喂食

\documentclass{article}
\pagestyle{empty}
\usepackage{tikz}
\usetikzlibrary{calc,bending}
\begin{document}
\begin{tikzpicture}
  \node[circle,draw] (N) at (15em,2ex) {};
  \coordinate (C) at (0,0);
  \draw[-latex] (C) .. controls (-2.6em,-1.5em) and ($(N.south west)-(1ex,1ex)$) .. (N.south west);
\end{tikzpicture}
\end{document}

产量pdflatex​

如您所见，曲线和箭头尖端之间存在不必要的间隙。我该如何消除它？

如果我们将圆形节点改为具有shapes不同轴的椭圆节点（使用），也会出现同样的问题。

错误报告：http://github.com/pgf-tikz/pgf/issues/1079。

Answer 1

($(N.south west)-(1ex,1ex)$)将的值更改为($(N.south west)-(3ex,1ex)$)

\documentclass{article}
\pagestyle{empty}
\usepackage{tikz}
\usetikzlibrary{calc,bending}
\begin{document}
\begin{tikzpicture}
  \node[circle,draw] (N) at (15em,2ex) {};
  \coordinate (C) at (0,0);
  \draw[-latex] (C) .. controls (-2.6em,-1.5em) and ($(N.south west)-(3ex,1ex)$) .. (N.south west);
\end{tikzpicture}
\end{document}

编辑插图：

足够距离：（2,1）

\documentclass{article}
\pagestyle{empty}
\usepackage{tikz}
\usetikzlibrary{calc,bending}
\begin{document}
\begin{tikzpicture}

     \node[circle,draw] (a) at (0,0) {1};
     \node[circle,draw] (b) at (1,1) {2};
     \node[circle,draw] (c) at (2,1) {3};
     \node[circle,draw] (d) at (2,0) {4};

    \draw[-latex] (a) .. controls (b) and (c) .. (d.north west);
\end{tikzpicture}

\end{document}

距离不足：（2,0.1）

\documentclass{article}
\pagestyle{empty}
\usepackage{tikz}
\usetikzlibrary{calc,bending}
\begin{document}
\begin{tikzpicture}

     \node[circle,draw] (a) at (0,0) {1};
     \node[circle,draw] (b) at (1,1) {2};
     \node[circle,draw] (c) at (2,0.1) {3};
     \node[circle,draw] (d) at (2,0) {4};

    \draw[-latex] (a) .. controls (b) and (c) .. (d.north west);
\end{tikzpicture}

\end{document}