边注：垂直对齐 - 段落长度的一半

Question 1

您可以尝试这样的操作，保存段落并测量其大小并输出恢复参数的文本。

\documentclass{scrreprt}

\usepackage{lipsum,blindtext} % Dummy text
\usepackage{marginnote} % Margin note
\renewcommand*{\marginfont}{\sffamily\footnotesize} % Format of margin

\newsavebox\mytempbox
\newlength{\currparindent}
\newcommand{\parwithmarginnote}[2]{\setlength{\currparindent}{\parindent}%
\sbox{\mytempbox}{%
  \parbox[t]{\textwidth}{\setlength{\parindent}{\currparindent}
  #2\par
  \xdef\myprevdepth{\the\prevdepth}%
  }%
}%
\marginnote{#1}[.5\dp\mytempbox]\par\noindent
\usebox{\mytempbox}\par
\prevdepth\myprevdepth}

\begin{document}

\lipsum[1]

\parwithmarginnote{Lorem ipsum}{\blindtext}

\lipsum[2]

\end{document}

Answer

您可以尝试这样的操作，保存段落并测量其大小并输出恢复参数的文本。

\documentclass{scrreprt}

\usepackage{lipsum,blindtext} % Dummy text
\usepackage{marginnote} % Margin note
\renewcommand*{\marginfont}{\sffamily\footnotesize} % Format of margin

\newsavebox\mytempbox
\newlength{\currparindent}
\newcommand{\parwithmarginnote}[2]{\setlength{\currparindent}{\parindent}%
\sbox{\mytempbox}{%
  \parbox[t]{\textwidth}{\setlength{\parindent}{\currparindent}
  #2\par
  \xdef\myprevdepth{\the\prevdepth}%
  }%
}%
\marginnote{#1}[.5\dp\mytempbox]\par\noindent
\usebox{\mytempbox}\par
\prevdepth\myprevdepth}

\begin{document}

\lipsum[1]

\parwithmarginnote{Lorem ipsum}{\blindtext}

\lipsum[2]

\end{document}

Question 2

所要求的功能需要有自己的软件包，事实上，这类功能需要比 LaTeX 为其用户提供的（LaTeX 只是 TeX 上的一层薄薄的层）更结构化的文档布局。如今，LuaTeX 可能提供了段落构建所需的钩子。

不管怎样，我们采用穷人的方法（这种方法甚至不考虑marginnote包的实现方式）。当然，它有一些相当严重的局限性：其中一个是段落跨两页的情况……

这\myparnote 必须在源文件的段落末尾使用。

作为包的marginnote使用\pdfsavepos等等...至少需要 2 次编译。

\documentclass{article}

\usepackage{marginnote}
\usepackage{ragged2e}

\newcommand\myparnote[1]{%
  \par
  \xdef\zzz{\the\prevgraf}%
  \marginnote{\smash{\parbox{\marginparwidth}{\RaggedRight#1}}}%
             [-0.5\dimexpr\numexpr1+\zzz\relax\baselineskip\relax]%
}

\begin{document}
The command
\verb|\vadjust(filler){vertical mode material}|
is only allowed in horizontal and math modes (but it is not a (horizontal
command). Vertical mode material specified by \verb|\vadjust| is moved from the
horizontal list in which the command is given to the surrounding vertical
list, directly after the box in which it occurred.
\myparnote{Hello}

Any vertical material in a \verb|\vadjust| item is processed in internal
vertical mode, even though it will wind up on the main vertical list. For
instance, the \verb|\ifinner| test is true in a \verb|\vadjust|, and at the
start of the vertical material \verb|\prevdepth|=-1000pt.
\myparnote{I am here!}

The command
\verb|\vadjust(filler){vertical mode material}|
is only allowed in horizontal and math modes (but it is not a (horizontal
command). Vertical mode material specified by \verb|\vadjust| is moved from the
horizontal list in which the command is given to the surrounding vertical
list, directly after the box in which it occurred.
Any vertical material in a \verb|\vadjust| item is processed in internal
vertical mode, even though it will wind up on the main vertical list. For
instance, the \verb|\ifinner| test is true in a \verb|\vadjust|, and at the
start of the vertical material \verb|\prevdepth|=-1000pt.
\myparnote{Hi again,
  it's me, and look how nice vertically centered I am.}

\end{document}

正如上面所示，OP 留下了一些关于“垂直对齐”的确切含义的关键问题，所以我们进行了猜测。

Answer