平均能量损失

Question

这是这个问题。

我正在尝试插入不占用垂直空间但对齐方式与正常插入相同的文本。

链接问题中提供的解决方案对我来说很有效，除非我的文本不占用任何空间，并且以列表环境开头。在这种情况下，\parbox文本顶部对齐，而不是基线对齐。

我怎样才能解决这个问题？

平均能量损失

\documentclass[twocolumn]{article}
\usepackage{ifluatex}
\ifluatex
  \usepackage{lua-visual-debug}
\fi
\usepackage{enumitem}
\newdimen\savedparindent
\newdimen\savedparskip
\newcommand{\blap}[1]{%
  \savedparindent\parindent
  \savedparskip\parskip
  \noindent
  \parbox[t][0pt]{\linewidth}{%
    \parindent\savedparindent
    \parskip\savedparskip
    #1}%
  \vspace*{-\parskip}\vspace*{-\baselineskip}}
\pagestyle{empty}
\begin{document}
Some text.

\blap{This should not take up any vertical space, but should align at normal
text baseline (aligned like I want).}

\vspace{2cm}

More text.

\blap{%
  \begin{itemize}[nosep]
    \item This should not take up any vertical space, but should align at
      normal text baseline (not aligned like I want).
  \end{itemize}}

\vspace{2cm}

Yet more text.

\begin{itemize}[nosep]
  \item This text takes up vertical space and aligns at normal text baseline
    (aligned like I want for comparison).
\end{itemize}

\newpage

Some text.

\vspace{2cm}

More text.

\vspace{2cm}

Yet more text.

\end{document}

Answer 1

这是由于\parbox和 后面的之间的交互不良造成的itemize。例如，这个答案. 解决方法：改用minipage。

\documentclass[twocolumn]{article}
\usepackage{enumitem}
\newdimen\savedparindent
\newdimen\savedparskip
\newcommand{\blap}[1]{%
  \savedparindent\parindent
  \savedparskip\parskip
  \noindent
  \begin{minipage}[t][0pt]{\linewidth}
    \parindent\savedparindent
    \parskip\savedparskip
    #1%
  \end{minipage}%
  \vspace*{-\parskip}\vspace*{-\baselineskip}}
\pagestyle{empty}
\begin{document}
Some text.

\blap{This should not take up any vertical space, but should align at normal
text baseline (aligned like I want).}

\vspace{2cm}

More text.

\blap{%
  \begin{itemize}[nosep]
    \item This should not take up any vertical space, but should align at
      normal text baseline (not aligned like I want).
  \end{itemize}}

\vspace{2cm}

Yet more text.

\begin{itemize}[nosep]
  \item This text takes up vertical space and aligns at normal text baseline
    (aligned like I want for comparison).
\end{itemize}

\newpage

Some text.

\vspace{2cm}

More text.

\vspace{2cm}

Yet more text.

\end{document}

Answer 2

只是为了好玩，我尝试使用\smash{\vtop{...}}for \blap。唉，它仍然在 itemize 之前添加了一行。

看完之后此链接我发现\@minipagetrue已经摆脱了多余的空间。

\documentclass[twocolumn]{article}
\usepackage{ifluatex}
\ifluatex
  \usepackage{lua-visual-debug}
\fi
\usepackage{enumitem}

\makeatletter
\newcommand{\blap}[1]{\par\vskip-\parskip
  \noindent\smash{\vtop{\@minipagetrue
    #1}}%
  \vspace{-\baselineskip}\allowbreak}
\makeatother

\pagestyle{empty}

\begin{document}

Some text.

\blap{%
This should not take up any vertical space, but should align at normal
text baseline (aligned like I want).}

\vspace{2cm}

More text.

\blap{%
\begin{itemize}[nosep]
    \item This should not take up any vertical space, but should align at
      normal text baseline (not aligned like I want).
\end{itemize}}

\vspace{2cm}

Yet more text.

\begin{itemize}[nosep]
  \item This text takes up vertical space and aligns at normal text baseline
    (aligned like I want for comparison).
\end{itemize}



\newpage

Some text.

\vspace{2cm}

More text.

\vspace{2cm}

Yet more text.

\end{document}