如何将一行文本缩放到精确的宽度

Question

我想缩放一些文本行，使它们在左侧和右侧完美对齐。使用 resizebox* 几乎可以正常工作，但边缘处有一点空白。字体越大，空白越大。

\documentclass{article}
\usepackage{graphicx}
\setkeys{Gin}{keepaspectratio} % to maintain aspect ratio of content inside resizebox
\setlength{\fboxsep}{0cm} % So that we can see the exact box around some text


\begin{document}%
    \setlength{\parindent}{0cm}
    \fbox{\resizebox*{12cm}{2cm}{OOOOOOOOOOOOOOOOOOOOOO}}\\%
    \fbox{\resizebox*{12cm}{2cm}{OOOOOOOOOOOOOO}}\\%
    \fbox{\resizebox*{12cm}{2cm}{OOOOOO}}\\%
\end{document}

它产生如下输出：

Answer 1

如果您愿意使用 XeLaTeX，您可以毫不费力地做到这一点。

\documentclass{article}
\usepackage{fontspec}
\usepackage{graphicx}

\newcommand{\removeleft}[1]{%
  \leavevmode\kern-\XeTeXglyphbounds1 \the\XeTeXcharglyph`#1\relax
  #1%
}
\newcommand{\removeright}[1]{%
  #1%
  \kern-\XeTeXglyphbounds3 \the\XeTeXcharglyph`#1\relax
}

\setlength{\parindent}{0pt}
\setlength{\fboxsep}{0pt}

\begin{document}

\fbox{\resizebox{12cm}{!}{\removeleft{O}OOOOOOOOOOOOOOOOOOOO\removeright{O}}}

\fbox{\resizebox{12cm}{!}{\removeleft{O}OOOOOOOOOOOO\removeright{O}}}

\fbox{\resizebox{12cm}{!}{\removeleft{O}OOOO\removeright{O}}}

\end{document}

XeTeX 文档中解释了这个技巧。首先，我们获取第一个字符的字形编号，然后测量其左侧边距。最后一个字符也一样。

通过一些expl3技巧，我们可以避免分离第一个字母和最后一个字母：

\documentclass{article}
\usepackage{fontspec}
\usepackage{graphicx}

\newcommand{\remove}[2]{%
  \leavevmode\kern-\XeTeXglyphbounds#2\space\the\XeTeXcharglyph`#1\relax
}

\ExplSyntaxOn
\cs_set_eq:NN \tobyone_remove_sb:nn \remove
\cs_generate_variant:Nn \tobyone_remove_sb:nn { fn }

\NewDocumentCommand{\removesidebearings}{m}
 {
  \tobyone_remove_sb:fn { \tl_head:n { #1 } } { 1 }% left
  #1
  \tobyone_remove_sb:fn { \tl_head:f { \tl_reverse:n { #1 } } } { 3 }
 }
\ExplSyntaxOff

\setlength{\parindent}{0pt}
\setlength{\fboxsep}{0pt}

\begin{document}

\fbox{\resizebox{12cm}{!}{\removesidebearings{OOOOOOOOOOOOOOOOOOOOOO}}}

\fbox{\resizebox{12cm}{!}{\removesidebearings{OOOOOOOOOOOOOO}}}

\fbox{\resizebox{12cm}{!}{\removesidebearings{OOOOOO}}}

\end{document}

如果还需要 TeX 的特殊字符，请按如下方式添加定义并使用“符号名称”。

\documentclass{article}
\usepackage{fontspec}
\usepackage{graphicx}

\newcommand{\remove}[2]{%
  \leavevmode\kern-\XeTeXglyphbounds#2\space\the\XeTeXcharglyph`#1\relax
}

\ExplSyntaxOn
\cs_set_eq:NN \tobyone_remove_sb:nn \remove
\cs_generate_variant:Nn \tobyone_remove_sb:nn { fn }

\NewDocumentCommand{\removesidebearings}{m}
 {
  \tobyone_remove_sb:fn { \tl_head:n { #1 } } { 1 }% left
  #1
  \tobyone_remove_sb:fn { \tl_head:f { \tl_reverse:n { #1 } } } { 3 }
 }

\cs_set_eq:NN \ampersandchar  \c_ampersand_str
\cs_set_eq:NN \backslashchar  \c_backslash_str
\cs_set_eq:NN \leftbracechar  \c_left_brace_str
\cs_set_eq:NN \rightbracechar \c_right_brace_str
\cs_set_eq:NN \circumflexchar \c_circumflex_str
\cs_set_eq:NN \dollarchar     \c_dollar_str
\cs_set_eq:NN \hashchar       \c_hash_str
\cs_set_eq:NN \percentchar    \c_percent_str
\cs_set_eq:NN \tildechar      \c_tilde_str
\cs_set_eq:NN \underscorechar \c_underscore_str
\ExplSyntaxOff

\setlength{\parindent}{0pt}
\setlength{\fboxsep}{0pt}

\begin{document}

\fbox{\resizebox{12cm}{!}{\removesidebearings{\dollarchar abc\rightbracechar}}}

\fbox{\resizebox{12cm}{!}{\dollarchar abc\rightbracechar}}

\end{document}

Answer 2

这是可行的，但它基于反复试验（没有干净的解决方案）：

\documentclass{article}
\usepackage{graphicx}
\setkeys{Gin}{keepaspectratio} % to maintain aspect ratio of content inside resizebox
\setlength{\fboxsep}{0cm} % So that we can see the exact box around some text

\newlength\mycor
\mycor=-0.555428pt

\begin{document}%
    \setlength{\parindent}{0cm}
    \fbox{\resizebox*{12cm}{2cm}{\hspace*{\mycor}OOOOOOOOOOOOOOOOOOOOOO}\hspace*{\mycor}}\\%
    \fbox{\resizebox*{12cm}{2cm}{\hspace*{\mycor}OOOOOOOOOOOOOO\hspace*{\mycor}}}\\%
    \fbox{\resizebox*{12cm}{2cm}{\hspace*{\mycor}OOOOOO\hspace*{\mycor}}}\\%
\end{document}