路径只是一条穿过节点然后分成三条的路径。当穿过包含文本的节点时，它应该变暗，或者甚至更好地向节点中心淡出，然后在离开节点时恢复其完整颜色。 等没有transparency帮助opacity。
% uses-*- MODE: latex; TeX-engine: luatex; coding: utf-8; -*-
\documentclass[fontsize=10pt]{standalone}
\usepackage[main=latin]{babel}
\usepackage{fontspec}
\usepackage{tikz}
\usetikzlibrary{positioning, decorations.pathmorphing, arrows.meta,
automata, decorations.pathreplacing, decorations.shapes,
decorations.text, fadings, patterns}
\setmainfont{TeX Gyre Pagella X}
\begin{document}
\tikzset{x=.7cm,y=.7cm}
\begin{tikzpicture}
\begin{scope}[align=center, every node/.style={draw, circle},>=stealth]
\node(Cotta) at (5,5) {C.~Aurelius Cotta};
\node(Balbus) at (0,0) {Q.~Lucilius Balbus};
\node(Velleius) at (10,0) {C.~Velleius};
\node[minimum width=2](Cicero) at (5,-5) {M.~Tullius Cicero};
\node[minimum width=2](Lector) at (5, -10) {Lector};
\end{scope};
\begin{scope}[every path/.style={black, decorate, decoration={waves}}]
\draw (Lector) -- (5,-5);
\draw (5,-5) -- (Balbus) ;
\draw (5,-5) -- (Cotta) ;
\draw (5,-5) -- (Velleius);
\end{scope};
\end{tikzpicture}
\end{document}
答案1
以手册中的例子来说，您可以声明基于径向阴影的淡入淡出，而不是真实的使用占位符的颜色transparent：
\tikzfading[name=fade out, inner color=transparent!0, outer color=transparent!100]
然后您可以path fading=fade out, fill=white在 Cicero 节点上使用：
\node[minimum width=2, path fading=fade out, fill=white]
(Cicero) at (5, -5) {M.~Tullius Cicero};
波浪路径需要放在这个节点后面，在这种情况下，最简单的方法是通过库on background layer来完成backgrounds。
如果你不喜欢这种褪色效果，我们需要通过以下方式实现另一种阴影\pgfdeclareradialshading或使用预定义的衰落circle with fuzzy edge XX percent，其中XX代表10，15或20（相当刺耳）。
根据您的 PDF 渲染器，您可能会体验到不同的结果。
代码
% arara: lualatex
\documentclass[fontsize=10pt]{standalone}
\usepackage[main=latin]{babel}
\usepackage{fontspec}
\usepackage{tikz}
\usetikzlibrary{positioning, decorations.pathreplacing, backgrounds, fadings}
\setmainfont{TeX Gyre Pagella X}
\tikzfading[name=fade out, inner color=transparent!0, outer color=transparent!100]
\begin{document}
\tikzset{x=.7cm,y=.7cm}
\begin{tikzpicture}
\begin{scope}[align=center, every node/.style={draw, circle}]
\node(Cotta) at (5,5) {C.~Aurelius Cotta};
\node(Balbus) at (0,0) {Q.~Lucilius Balbus};
\node(Velleius) at (10,0) {C.~Velleius};
\node[minimum width=2, path fading=fade out, fill=white] % ← add fading
(Cicero) at (5, -5) {M.~Tullius Cicero};
\node[minimum width=2](Lector) at (5, -10) {Lector};
\end{scope};
\begin{scope}[
every path/.style={decorate, decoration={waves}},
on background layer] % ← on background
\draw (Lector) -- (Cicero.center);
\draw (Cicero.center) -- (Balbus) ;
\draw (Cicero.center) -- (Cotta) ;
\draw (Cicero.center) -- (Velleius);
\end{scope};
\end{tikzpicture}
\end{document}
输出
