在 tcolorbox 中创建笔记本纸的外观；绘制正确线条数时出现问题

Question 1

我建议使用tcolorbox的子皮肤enhanced（适用于可破坏的盒子）来实现这一点。在下面给出的代码中，我们定义了一个paper源自的皮肤enhanced，并使其tcolorbox样式paper发挥作用skin=paper（其中包括设置所需的框架和背景颜色）。我们还定义了三个子皮肤paperfirst、papermiddle和，paperlast分别源自enhancedfirst、enhancedmiddle和enhancedlast；这些允许我们在所有情况下为盒子提供所需的外观（未破坏、顶部破坏但底部不破坏、底部破坏但顶部不破坏、顶部和底部均破坏）。

由于enhanced皮肤设置了，它定义了名为、、和/tcb/geometry nodes=true的节点，这些节点允许我们访问的有趣点。在这里，可以使用或来计算框高度（它们给出的结果并不完全相同，因为、和属于但不属于）。在下面定义的皮肤中，我们使用节点来计算要绘制的水平规则的数量，以及和的适当组合作为垂直规则的范围，具体取决于框是否在顶部断开以及是否在底部断开。例如，可以使用来计算要绘制的水平规则的数量（也可以在调用内部使用来完成）。frameinteriorsegmentationtitletcolorboxframeinterior/tcb/leftrule/tcb/toprule/tcb/rightrule/tcb/bottomruleframeinteriorpaperinteriorframeinterior\pgfmathtruncatemacroint()\pgfmathsetmacro

注意：我对您的样式做了一点小改动normal lines。较大line width，但规则是用绘制的opacity=...，如所定义/tcb/paper/rule opacity。此绘制是在内完成的，transparency group其目的是确保规则交叉点不会比规则中的其他地方更暗。

\documentclass{article}
\usepackage{tcolorbox}
\tcbuselibrary{breakable, skins}
\usepackage{tikz}
\usetikzlibrary{calc}
\usepackage{lipsum}

\makeatletter

\tikzset{normal lines/.style={gray, thin}}
\tcbset{paper/left margin/.initial=1.25in,
        paper/line spacing/.initial=1cm,
        paper/rule opacity/.initial=0.4,
        paper/.style={
          skin=paper, colback=green!10, colframe=green!65!black,
          breakable, left=1.3in,
        }
}

\newif\if@paper@broken@top
\newif\if@paper@broken@bottom
\pgfkeys{/tcb/paper/broken top/.is if=@paper@broken@top,
         /tcb/paper/broken bottom/.is if=@paper@broken@bottom
}

% The various parts don't have the same skin when a box is broken. This also
% influences where we want the vertical rule to extend to.
\tcbsubskin{paperfirst}{enhancedfirst}{
  paper/broken top=false, paper/broken bottom=true
}
\tcbsubskin{papermiddle}{enhancedmiddle}{
  paper/broken top=true, paper/broken bottom=true
}
\tcbsubskin{paperlast}{enhancedlast}{
  paper/broken top=true, paper/broken bottom=false
}

\tcbsubskin{paper}{enhanced}{
  skin first=paperfirst, skin middle=papermiddle, skin last=paperlast,
  paper/broken top=false, paper/broken bottom=false,
  overlay={
    \begin{tcbclipinterior}
    \begin{scope}[opacity=\pgfkeysvalueof{/tcb/paper/rule opacity},
                  transparency group]
    % Make sure the vertical rule extends exactly as far as we want, depending
    % on where the box is broken.
    \if@paper@broken@top
      \coordinate (top for vert rule) at (frame.north west);
    \else
      \coordinate (top for vert rule) at (interior.north west);
    \fi
    %
    \if@paper@broken@bottom
      \coordinate (bottom for vert rule) at (frame.south west);
    \else
      \coordinate (bottom for vert rule) at (interior.south west);
    \fi
    %
    \draw[transform canvas={xshift=\pgfkeysvalueof{/tcb/paper/left margin}},
          style=normal lines] (top for vert rule) -- (bottom for vert rule);
    %
    \path let \p1=($(interior.north)-(interior.south)$) in
      \pgfextra{%
        \pgfmathtruncatemacro{\tmp}{veclen(\p1) /
                                    \pgfkeysvalueof{/tcb/paper/line spacing}}%
        \xdef\paperskin@nblines{\tmp}};
    \foreach \i in {1,..., \paperskin@nblines} {
       \pgfmathsetlengthmacro{\paperskin@shift}{
         -\i*\pgfkeysvalueof{/tcb/paper/line spacing}}
       \draw[style=normal lines]
         ([yshift=\paperskin@shift]interior.north west) --
         ([yshift=\paperskin@shift]interior.north east);
    }
    \end{scope}
    \end{tcbclipinterior}
  },
}

\makeatother

\pagestyle{empty}

\begin{document}

\lipsum[1]
\begin{tcolorbox}[paper]
\lipsum[2]
\end{tcolorbox}

\lipsum[3]
\begin{tcolorbox}[paper]
\lipsum[4-5]
\end{tcolorbox}

\end{document}

未破损的盒子：

first破损盒子的一部分：

last破损盒子的一部分：

部分middle（顶部断裂和（在底部）也将绘制得很好，并且垂直线延伸到所需的长度：

注意：我的代码如下部分：

\tcbsubskin{paper}{enhanced}{
  ...
  overlay={
    ...
    % Make sure the vertical rule extends exactly as far as we want, depending
    % on where the box is broken.
    \if@paper@broken@top
      \coordinate (top for vert rule) at (frame.north west);
    \else
      \coordinate (top for vert rule) at (interior.north west);
    \fi
    %
    \if@paper@broken@bottom
      \coordinate (bottom for vert rule) at (frame.south west);
    \else
      \coordinate (bottom for vert rule) at (interior.south west);
    \fi

也可以这样写：

\newcommand*{\paper@defcoord}[3]{
  \coordinate (#2 for vert rule) at (#1.#3 west);
}

\tcbsubskin{paper}{enhanced}{
  ...
  overlay={
    ...
    % Make sure the vertical rule extends exactly as far as we want, depending
    % on where the box is broken.
    \edef\tmp{\if@paper@broken@top frame\else interior\fi}
    \expandafter\paper@defcoord\expandafter{\tmp}{top}{north}
    \edef\tmp{\if@paper@broken@bottom frame\else interior\fi}
    \expandafter\paper@defcoord\expandafter{\tmp}{bottom}{south}

但第一种方法看起来更容易阅读，因此我决定在完整的示例中保留这种方法。

Answer