如何在 Beamer 讲义上绘制水平线？

Question

我有一份通过 提供的 16 合 1 布局的投影仪讲义\pgfpagesuselayout{16 on 1}。

我想在每行幻灯片下方画一条水平线，以便观众更容易从左到右阅读，而不是先从上到下阅读。

可能这是一个论点\pgfpagesuselayout？

我可以使用以下命令在整个框架周围绘制边框：

\pgfpageslogicalpageoptions{1}{border code=\pgfusepath{stroke}}

但实际上我只是想要在第 1、2 和 3 行幻灯片底部有一个长边框。

这是一个关于处处边界的最小工作示例：

\documentclass[xcolor=dvipsnames, handout]{beamer}

\usepackage{pgfpages}
\beamertemplatenavigationsymbolsempty
\pgfpagesuselayout{16 on 1}[a0paper,border shrink=5mm, landscape]

\pgfpageslogicalpageoptions{1}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{2}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{3}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{4}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{5}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{6}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{7}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{8}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{9}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{10}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{11}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{12}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{13}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{14}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{15}{border code=\pgfusepath{stroke}}
\pgfpageslogicalpageoptions{16}{border code=\pgfusepath{stroke}}


\begin{document}

\begin{frame}[plain]
  \titlepage
\end{frame}


\end{document}

Answer 1

您可以通过一些巧妙的border code方法来实现这一点，即丢弃给定的路径（即每个子页面周围的框）并仅为相关页面绘制底线，但我不认为这看起来那么好，因为线条不会连接并且不会垂直居中（因为页面略微缩小了）。

因此，这里有一个替代方案，它定义了一个“背景”页面，该页面位于所有其他页面的后面，并占据了整个页面。我们在此绘制三条水平线。pgfpages页面收集机制永远不会写入这三条水平线，而是从（物理）页面复制到（物理）页面。唯一的缺点是，如果您总共有 17 张幻灯片，那么第二个物理页面（只有一个逻辑页面）上仍然绘制了所有三条线。

代码如下：

\documentclass[xcolor=dvipsnames, handout]{beamer}

\usepackage{pgfpages}
\usepackage{pgffor}
\beamertemplatenavigationsymbolsempty

\pgfpagesdeclarelayout{16 on 1 with background}
{
  \edef\pgfpageoptionheight{\the\paperheight} 
  \edef\pgfpageoptionwidth{\the\paperwidth}
  \edef\pgfpageoptionborder{0pt}
}
{
  \pgfpagesphysicalpageoptions
  {%
    logical pages=17,%
    physical height=\pgfpageoptionheight,%
    physical width=\pgfpageoptionwidth,%
    first logical shipout=2,%
  }
  \pgfpageslogicalpageoptions{1}
  {%
    resized width=\pgfphysicalwidth,%
    resized height=\pgfphysicalheight,%
    center=\pgfpoint{.5\pgfphysicalwidth}{.5\pgfphysicalheight},%
    border code={%
      \pgfusepath{discard}%
      \pgfpathmoveto{\pgfpoint{0pt}{.25\ht0}}%
      \pgfpathlineto{\pgfpoint{\wd0}{.25\ht0}}%
      \pgfpathmoveto{\pgfpoint{0pt}{.5\ht0}}%
      \pgfpathlineto{\pgfpoint{\wd0}{.5\ht0}}%
      \pgfpathmoveto{\pgfpoint{0pt}{.75\ht0}}%
      \pgfpathlineto{\pgfpoint{\wd0}{.75\ht0}}%
      \pgfusepath{stroke}%
    },%
    copy from=1,%
  }%
  \pgfpageslogicalpageoptions{2}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.125\pgfphysicalwidth}{.875\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{3}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.375\pgfphysicalwidth}{.875\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{4}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.625\pgfphysicalwidth}{.875\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{5}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.875\pgfphysicalwidth}{.875\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{6}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.125\pgfphysicalwidth}{.625\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{7}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.375\pgfphysicalwidth}{.625\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{8}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.625\pgfphysicalwidth}{.625\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{9}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.875\pgfphysicalwidth}{.625\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{10}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.125\pgfphysicalwidth}{.375\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{11}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.375\pgfphysicalwidth}{.375\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{12}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.625\pgfphysicalwidth}{.375\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{13}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.875\pgfphysicalwidth}{.375\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{14}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.125\pgfphysicalwidth}{.125\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{15}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.375\pgfphysicalwidth}{.125\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{16}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.625\pgfphysicalwidth}{.125\pgfphysicalheight}%
  }%
  \pgfpageslogicalpageoptions{17}
  {%
    border shrink=\pgfpageoptionborder,%
    resized width=.25\pgfphysicalwidth,%
    resized height=.25\pgfphysicalheight,%
    center=\pgfpoint{.875\pgfphysicalwidth}{.125\pgfphysicalheight}%
  }%
}

\pgfpagesuselayout{16 on 1 with background}[a0paper,border shrink=5mm, landscape]



\begin{document}

\begin{frame}[plain]
  \titlepage
\end{frame}

\foreach \k in {1,...,31} {
  \begin{frame}{Frame \k}
  This is frame \k
  \end{frame}
}

\end{document}

结果：