重复不规则线条

Question

我想要创建两条不规则的线条，一条叠在另一条之上，遵循相同的模式。

关注 @vialrogo 对帖子的回答在技​​术图纸上随意绘制参差不齐的线条我已经走到这一步了，但我需要线条相同、不规则并且一个接一个地出现。

有没有办法可以精确复制随机线条？或者是否有其他代码可以让我生成两条不规则的线条，它们相等但相互重叠？

\documentclass[]{standalone}
\usepackage{tikz} % To plot almost everything.
\usetikzlibrary{fit, calc, matrix, positioning, arrows.meta, intersections, through, backgrounds, patterns}
\usepackage{xparse}

\begin{document}
\begin{tikzpicture}
\NewDocumentCommand{\irregularline}{%
  O     {2mm}   % Amplitude of irregularity. Optional. Default value = 2mm
  m             % First point
  m            % Second point
  D   <> {20}   % Number of peaks. Optional. Default value = 20
}{{%
  \coordinate (old) at #2;
  \foreach \i in {1,2,...,#4}{
  \draw (old) -- ($ ($#2!\i/(#4+1)!#3$) + (0,#1*rand) $) coordinate (old);
  }
  \draw (old) -- #3;
}}

\irregularline[1mm]{(0,0)}{(5,0)}
\irregularline[1mm]{(0,1)}{(5,1)}
\irregularline[1mm]{(0,1.5)}{(5,1.5)}
\end{tikzpicture}

\end{document}

Answer 1

在 的定义中的循环之前添加\pgfmathsetseed{42}（或使用您选择的其他数字）\irregularline。

\documentclass[]{standalone}
\usepackage{tikz} % To plot almost everything.
\usetikzlibrary{fit, calc, matrix, positioning, arrows.meta, intersections, through, backgrounds, patterns}
\usepackage{xparse}

\begin{document}
\begin{tikzpicture}
\NewDocumentCommand{\irregularline}{%
  O     {2mm}   % Amplitude of irregularity. Optional. Default value = 2mm
  m             % First point
  m            % Second point
  D   <> {20}   % Number of peaks. Optional. Default value = 20
}{{%
  \coordinate (old) at #2;
  \pgfmathsetseed{42} % <-- added
  \foreach \i in {1,2,...,#4}{
  \draw (old) -- ($ ($#2!\i/(#4+1)!#3$) + (0,#1*rand) $) coordinate (old);
  }
  \draw (old) -- #3;
}}

\irregularline[1mm]{(0,0)}{(5,0)}
\irregularline[1mm]{(0,1)}{(5,1)}
\irregularline[1mm]{(0,1.5)}{(5,1.5)}
\end{tikzpicture}

\end{document}

Answer 2

只是为了完整性，也就是说，你不需要这个漂亮的宏来绘制一条随机线，也不需要你加载的所有库。使用Torbjørn T. 的回答以及 pgfmanual 第 48.2 节：

\documentclass[tikz,border=5pt]{standalone}
\usetikzlibrary{decorations.pathmorphing}
\begin{document}
\begin{tikzpicture}
    \pgfmathsetseed{42}
    \draw[decorate,decoration={random steps,segment length=4pt,amplitude=2pt}] 
    (0, 0) -- (5,0);
    \pgfmathsetseed{42}
    \draw[decorate,decoration={random steps,segment length=4pt,amplitude=2pt}] 
    (0, -1) -- (5,-1);
\end{tikzpicture}
\end{document}