%%% file `obchapterstyles.sty`
%%% 	subpackage of oblivoir
%%%
%%% written by Kangsoo Kim, 2024--2025
%%%
%%% chapter styles provided by oblivoir
%%%
\ProvidesPackage{obchapterstyles}[2025/04/04, chapter styles]
%%%
%%%%%%%%%%%%%%%% chapterstyles from memhangul %%%%%%%%%%%%%%%

\makechapterstyle{section}{%
%  \renewcommand{\printchaptername}{}
  \renewcommand{\chapternamenum}{\enskip}
  \renewcommand{\prechapternum}{}
  \renewcommand{\postchapternum}{}
  \renewcommand{\chapnumfont}{\normalfont\Huge\bfseries}
  \renewcommand{\printchapternum}{\chapnumfont \thechapter\space}
  \renewcommand{\afterchapternum}{}
}

%% for appendix
\makechapterstyle{appendixsection}{%
%  \renewcommand{\printchaptername}{\chapnumfont\@chapapp}
  \renewcommand{\chapternamenum}{\enskip}
  \renewcommand{\prechapternum}{\chapnumfont\@chapapp}
  \renewcommand{\postchapternum}{}
  \renewcommand{\chapnumfont}{\normalfont\Huge\bfseries}
  \renewcommand{\printchapternum}{\chapnumfont \thechapter\space}
  \renewcommand{\afterchapternum}{}
}

\makechapterstyle{article}{%
  \renewcommand{\chapterheadstart}{\vspace{\beforechapskip}}
  \setlength{\beforechapskip}{3.5ex \@plus 1ex \@minus .2ex}
  \setlength{\afterchapskip}{2.3ex \@plus .2ex}
%  \renewcommand{\printchaptername}{}
  \renewcommand{\prechapternum}{}
  \renewcommand{\chapternamenum}{}
  \renewcommand{\postchapternum}{}
  \renewcommand{\chaptitlefont}{\normalfont\Large\bfseries}
  \renewcommand{\chapnumfont}{\normalfont\Large\bfseries}
  \renewcommand{\printchapternum}{\chapnumfont \thechapter\quad}
  \renewcommand{\afterchapternum}{}
}

\makechapterstyle{hangnum}{%
  \renewcommand{\chapnumfont}{\chaptitlefont}
  \settowidth{\chapindent}{\chapnumfont 999}
%  \renewcommand{\printchaptername}{}
  \renewcommand{\chapternamenum}{}
  \renewcommand{\prechapternum}{}
  \renewcommand{\postchapternum}{}
  \renewcommand{\printchapternum}{%
    \noindent\llap{\makebox[\chapindent][l]{\chapnumfont \thechapter}}}
  \renewcommand{\afterchapternum}{}
}

%\newlength{\chapindent}

\makechapterstyle{companion}{%
  \chapterstyle{default}
  \renewcommand*{\chapnamefont}{\normalfont\LARGE\scshape}
  \renewcommand*{\printchaptername}{\raggedleft\chapnamefont \@chapapp}
  \renewcommand*{\prechapternum}{\raggedleft\chapnamefont \pre@chapter}
  \renewcommand*{\chapnumfont}{\normalfont\Huge}
  \setlength{\chapindent}{\marginparsep}
  \addtolength{\chapindent}{\marginparwidth}
  \renewcommand*{\printchaptertitle}[1]{%
    \begin{adjustwidth}{}{-\chapindent}
      \raggedleft \chaptitlefont ##1\par\nobreak
    \end{adjustwidth}}} 

%% for appendix.
\makechapterstyle{appendixcompanion}{%
  \renewcommand{\chapnamefont}{\normalfont\LARGE\scshape}
  \renewcommand{\prechapternum}{\raggedleft\chapnamefont \@chapapp}
%  \renewcommand{\printchaptername}{\raggedleft\chapnamefont \pre@chapter}
  \renewcommand{\chapnumfont}{\normalfont\Huge}
  \renewcommand{\postchapternum}{}
  \setlength{\chapindent}{\marginparsep}
  \addtolength{\chapindent}{\marginparwidth}
  \renewcommand{\printchaptertitle}[1]{%
    \begin{adjustwidth}{}{-\chapindent}
      \raggedleft \chaptitlefont ##1\par\nobreak
    \end{adjustwidth}}
}

\makechapterstyle{demo}{
%  \renewcommand{\printchaptername}{\centering}
  \renewcommand{\prechapternum}{\centering}
  \renewcommand{\printchapternum}{\chapnumfont \numtoName{\c@chapter}}
  \renewcommand{\postchapternum}{}
  \renewcommand{\chaptitlefont}{\normalfont\Huge\sffamily}
  \renewcommand{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \raggedleft \chaptitlefont ##1}
  \renewcommand{\afterchaptertitle}{\vskip\onelineskip \hrule\vskip \afterchapskip}
}

\makechapterstyle{demovar}{
%  \renewcommand{\printchaptername}{\centering}
  \renewcommand{\prechapternum}{\centering}
  \renewcommand{\printchapternum}{\chapnumfont \hNum{chapter}}
  \renewcommand{\postchapternum}{\post@chapter}
  \renewcommand{\chaptitlefont}{\normalfont\Huge\sffamily}
  \renewcommand{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \raggedleft \chaptitlefont ##1}
  \renewcommand{\afterchaptertitle}{\vskip\onelineskip \hrule\vskip \afterchapskip}
}

%% for appendix
\makechapterstyle{appendixdemo}{
%  \renewcommand{\printchaptername}{\centering\chapnumfont\@chapapp}
  \renewcommand{\prechapternum}{\centering\chapnumfont\@chapapp}
  \renewcommand{\printchapternum}{\chapnumfont \@Alph\c@chapter}
  \renewcommand{\postchapternum}{\ }
  \renewcommand{\chaptitlefont}{\normalfont\Huge\sffamily}
  \renewcommand{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \raggedleft \chaptitlefont ##1}
  \renewcommand{\afterchaptertitle}{\vskip\onelineskip \hrule\vskip \afterchapskip}
}

%%%%%% styles from ob-chapstyles %%%%%

%% ob+
%% bianchi,bringhurst,brotherton,chappell,culver,
%% dash,demo2,demo3,ell,ger,lyhne,madsen,pedersen,
%% southall,thatcher,veelo,verville,crosshead,
%% dowding,komalike,ntglike,tandh,wilsondob
%%

\makechapterstyle{obbianchi}{%
  \chapterstyle{default}
  \renewcommand*{\chapnamefont}{\normalfont\Large\sffamily\itshape}
  \renewcommand*{\chapnumfont}{\normalfont\huge}
%  \renewcommand*{\printchaptername}{%
%    \chapnamefont\centering\@chapapp}
  \renewcommand*{\prechapternum}{\chapnamefont\centering 제}
  \renewcommand*{\postchapternum}{\chapnamefont 장}
  \renewcommand*{\hchaptertitlehead}{제\,\thechapter\,장}
  \renewcommand*{\printchapternum}{\chapnumfont \textit{\thechapter}}
  \renewcommand*{\chaptitlefont}{\normalfont\Huge\sffamily}
  \renewcommand*{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \centering \chaptitlefont\textbf{##1}\par}
  \renewcommand*{\afterchaptertitle}{\vskip\onelineskip \hrule\vskip
    \afterchapskip}
  \renewcommand*{\printchapternonum}{%
    \vphantom{\chapnumfont \textit{9}}\afterchapternum}}

\makechapterstyle{obbringhurst}{%
  \chapterstyle{default}
  \renewcommand*{\chapterheadstart}{}
%  \renewcommand*{\printchaptername}{}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\hchaptertitlehead}{}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\printchapternum}{}
  \renewcommand*{\afterchapternum}{}
  \renewcommand*{\printchaptertitle}[1]{%
%%%    \raggedright\Large\scshape\MakeLowercase{##1}}
    \memRTLraggedright\Large\scshape\MakeLowercase{##1}}
  \renewcommand*{\afterchaptertitle}{%
  \vskip\onelineskip \hrule\vskip\onelineskip}}

\makechapterstyle{obbrotherton}{%
  \chapterstyle{default}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\hchaptertitlehead}{\numtoName{\c@chapter}}
  \renewcommand*{\printchapternum}{\chapnumfont
    \ifanappendix \thechapter \else \numtoName{\c@chapter}\fi}}

\makechapterstyle{obchappell}{%
  \chapterstyle{default}
  \setlength{\beforechapskip}{0pt}
  \renewcommand*{\chapnamefont}{\large\centering}
  \renewcommand*{\chapnumfont}{\large}
  \renewcommand*{\printchapternonum}{%
    \vphantom{\printchaptername \chapnumfont 1}
    \afterchapternum
    \vskip \onelineskip \vskip -\topskip}
  \renewcommand*{\chaptitlefont}{\Large\itshape}
  \renewcommand*{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \centering\chaptitlefont ##1}}

\makechapterstyle{obculver}{%
  \chapterstyle{default}
  \chapterstyle{article}%
  \renewcommand*{\thechapter}{\Roman{chapter}}
  \renewcommand*{\printchapternum}{% center number/title
    \centering\chapnumfont \thechapter\space\space}%
  \renewcommand*{\printchapternonum}{\centering}
  \renewcommand*{\clearforchapter}{}% no new page
  \aliaspagestyle{chapter}{headings}}% no special pagestyle

\makechapterstyle{obdash}{%
  \chapterstyle{default}
  \setlength{\beforechapskip}{5\onelineskip}
%  \renewcommand*{\printchaptername}{}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\thechapter}{\arabic{chapter}}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\chapnumfont}{\normalfont\large}
  \settoheight{\midchapskip}{\chapnumfont 1}
  \renewcommand*{\printchapternum}{\centering \chapnumfont
    \rule[0.5\midchapskip]{1em}{0.4pt} \thechapter\
    \rule[0.5\midchapskip]{1em}{0.4pt}}
  \renewcommand*{\afterchapternum}{\par\nobreak\vskip 0.5\onelineskip}
  \renewcommand*{\printchapternonum}{\centering
                 \vphantom{\chapnumfont 1}\afterchapternum}
  \renewcommand*{\chaptitlefont}{\normalfont\Large}
  \renewcommand*{\printchaptertitle}[1]{\centering \chaptitlefont ##1}
  \setlength{\afterchapskip}{2.5\onelineskip}}

\makechapterstyle{obdemo2}{%
  \chapterstyle{default}
%  \renewcommand*{\printchaptername}{\centering}
  \renewcommand*{\prechapternum}{\centering}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\printchapternum}{\chapnumfont
     \ifanappendix \thechapter \else \numtoName{\c@chapter}\fi}
  \renewcommand*{\chaptitlefont}{\normalfont\Huge\sffamily}
  \renewcommand*{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \raggedleft \chaptitlefont ##1}
  \renewcommand*{\afterchaptertitle}{%
    \vskip\onelineskip \hrule\vskip \afterchapskip}
  \setlength{\beforechapskip}{3\baselineskip}
  \renewcommand*{\printchapternonum}{%
    \vphantom{\chapnumfont One}
    \afterchapternum%
    \vskip\topskip}
  \setlength{\beforechapskip}{2\onelineskip}}

\makechapterstyle{obdemo3}{%
  \chapterstyle{default}
%  \renewcommand*{\printchaptername}{\centering}
  \renewcommand*{\prechapternum}{\centering}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapnumfont}{\normalfont\HUGE\itshape}
  \renewcommand*{\printchapternum}{\chapnumfont
     \ifanappendix \thechapter \else \numtoName{\c@chapter}\fi}
  \renewcommand*{\chaptitlefont}{\normalfont\Huge\sffamily}
  \renewcommand*{\printchaptertitle}[1]{%
    \hrule\vskip\onelineskip \raggedleft \chaptitlefont ##1}
  \renewcommand*{\afterchaptertitle}{%
    \vskip\onelineskip \hrule\vskip \afterchapskip}
  \setlength{\beforechapskip}{0pt}
  \setlength{\midchapskip}{2\onelineskip}
  \setlength{\afterchapskip}{2\onelineskip}
  \renewcommand*{\printchapternonum}{%
    \vphantom{\chapnumfont One}
    \afterchapternum%
    \vskip\topskip}}

\makechapterstyle{obell}{%
  \chapterstyle{default}
  \renewcommand*{\chapnumfont}{\normalfont\HUGE\sffamily}
  \renewcommand*{\chaptitlefont}{\normalfont\huge\sffamily}
  \settowidth{\chapindent}{\chapnumfont 111}
  \renewcommand*{\chapterheadstart}{\begingroup
    \vspace*{\beforechapskip}%
    \begin{adjustwidth}{}{-\chapindent}%
    \hrulefill
    \smash{\rule{0.4pt}{15mm}}
    \end{adjustwidth}\endgroup}
%  \renewcommand*{\printchaptername}{}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\thechapter}{\arabic{chapter}}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\printchapternum}{%
    \begin{adjustwidth}{}{-\chapindent}
    \hfill
    \raisebox{10mm}[0pt][0pt]{\chapnumfont \thechapter}%
                              \hspace*{1em}
    \end{adjustwidth}\vspace*{-3.0\onelineskip}}
  \renewcommand*{\printchaptertitle}[1]{%
    \vskip\onelineskip
    \raggedleft {\chaptitlefont ##1}\par\nobreak}}

\makechapterstyle{obger}{%
  \chapterstyle{default}
  \renewcommand*{\chapterheadstart}{\vspace*{\beforechapskip}
  \mbox{}\\\mbox{}\rule[0pt]{\textwidth}{0.4pt}\par}
  \setlength{\midchapskip}{20pt}
  \renewcommand*{\printchaptertitle}[1]{\chaptitlefont ##1
    \\\mbox{}\rule[5pt]{\textwidth}{0.4pt}}}

\makechapterstyle{oblyhne}{%  needs graphicx package
  \chapterstyle{default}
  \setlength{\beforechapskip}{1.5cm}
  \setlength{\afterchapskip}{1cm}
  \setlength{\midchapskip}{2cm}
  \renewcommand*{\chapnamefont}{\normalfont\normalsize\scshape\raggedleft}
  \renewcommand*{\chaptitlefont}{\normalfont\normalsize\bfseries\sffamily\raggedleft}
  \renewcommand*{\prechapternum}{\chapnamefont Chapter}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\printchapternum}{\makebox[0pt][l]{\hspace{0.2em}%
    \resizebox{!}{2ex}{\chapnamefont\bfseries\sffamily\thechapter}}}
  \renewcommand*{\afterchapternum}{\par\hspace{1.5cm}\hrule\vspace{0.2cm}}
 \renewcommand*{\printchapternonum}{\vphantom{\chapnamefont 1}\afterchapternum}
  \renewcommand*{\afterchaptertitle}{\vskip 0.2cm
    \hrule\vskip\afterchapskip}}

\makechapterstyle{obmadsen}{% requires graphicx package
  \chapterstyle{default}
%  \renewcommand*{\chapnamefont}{%
%    \normalfont\Large\scshape\raggedleft}
  \renewcommand*{\prechapternum}{\normalfont\Large\scshape\raggedleft}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chaptitlefont}{%
    \normalfont\Huge\bfseries\sffamily\raggedleft}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\printchapternum}{%
    \makebox[0pt][l]{\hspace{0.4em}
      \resizebox{!}{4ex}{%
        \chapnamefont\bfseries\sffamily\thechapter}
    }%
  }%
  \renewcommand*{\printchapternonum}{%
    \chapnamefont \phantom{\printchaptername \chapternamenum \printchapternum}
    \afterchapternum %
  }%
  \renewcommand*{\afterchapternum}{%
    \par\hspace{1.5cm}\hrule\vskip\midchapskip}}

%\newcommand*{\colorchapnum}{}
%\newcommand*{\colorchaptitle}{}
\makechapterstyle{obpedersen}{%
  \chapterstyle{default}
  \setlength{\beforechapskip}{-20pt}
  \setlength{\afterchapskip}{10pt}
  \renewcommand*{\chapnamefont}{\normalfont\LARGE\itshape}
  \renewcommand*{\chapnumfont}{\normalfont\HUGE\itshape\colorchapnum}
  \renewcommand*{\chaptitlefont}{\normalfont\huge\itshape\colorchaptitle}
  \renewcommand*{\afterchapternum}{}
%  \renewcommand*{\printchaptername}{}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \setlength{\midchapskip}{20mm}% was \numberheight
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\printchapternum}{%
    \sidebar{\raisebox{0pt}[0pt][0pt]{\makebox[0pt][l]{%
      \resizebox{!}{\midchapskip}{\chapnumfont\thechapter}}}}}
  \renewcommand*{\printchaptertitle}[1]{\chaptitlefont ##1}}

%% Thomas Dye's southall chapter style
\makechapterstyle{obsouthall}{%
  \chapterstyle{default}
  \setlength{\afterchapskip}{5\baselineskip}
  \setlength{\beforechapskip}{36pt}%    \headindent
  \setlength{\midchapskip}{\textwidth}% \rightblock
  \addtolength{\midchapskip}{-\beforechapskip}
  \renewcommand*{\chapterheadstart}{\vspace*{2\baselineskip}}
%%%  \renewcommand*{\chaptitlefont}{\huge\rmfamily\raggedright}
  \renewcommand*{\chaptitlefont}{\huge\rmfamily\memRTLraggedright}
  \renewcommand*{\chapnumfont}{\chaptitlefont}
%  \renewcommand*{\printchaptername}{}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\afterchapternum}{}
  \renewcommand*{\printchapternum}{%
    \begin{minipage}[t][\baselineskip][b]{\beforechapskip}
      {\vspace{0pt}\chapnumfont%%%\figureversion{lining}
                   \thechapter}
    \end{minipage}}
  \renewcommand*{\printchaptertitle}[1]{%
    \hfill\begin{minipage}[t]{\midchapskip}
      {\vspace{0pt}\chaptitlefont ##1\par}\end{minipage}}
  \renewcommand*{\afterchaptertitle}{%
    \par\vspace{\baselineskip}%
    \hrulefill \par\nobreak\noindent \vskip \afterchapskip}}

\makechapterstyle{obthatcher}{%
  \chapterstyle{default}
  \renewcommand*{\chapterheadstart}{}
%  \renewcommand*{\printchaptername}{%
%    \centerline{\chapnumfont{\@chapapp\ \thechapter}}}
  \renewcommand*{\prechapternum}{\centerline{\chapnumfont Chapter\ \thechapter}}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}
  \renewcommand*{\chapnumfont}{\normalfont\scshape\MakeLowercase}
  \renewcommand*{\printchapternum}{}
  \renewcommand*{\afterchapternum}{%
    \par\centerline{\parbox{0.5in}{\hrulefill}}\par}
  \renewcommand*{\printchapternonum}{%
    \vphantom{\chapnumfont \@chapapp 1}\par
    \parbox{0.5in}{}\par}
  \renewcommand*{\chaptitlefont}{\normalfont\large}
  \renewcommand*{\printchaptertitle}[1]{%
    \centering \chaptitlefont\MakeUppercase{##1}}}

\makechapterstyle{obveelo}{%
   \setlength{\afterchapskip}{40pt}
  \renewcommand*{\chapterheadstart}{\vspace*{40pt}}
  \renewcommand*{\afterchapternum}{\par\nobreak\vskip 25pt}
   \renewcommand*{\chapnamefont}{\normalfont\LARGE\flushright}
   \renewcommand*{\chapnumfont}{\normalfont\HUGE}
   \renewcommand*{\chaptitlefont}{\normalfont\HUGE\bfseries\flushright}
%   \renewcommand*{\printchaptername}{%
%     \chapnamefont\MakeUppercase{\@chapapp}}
  \renewcommand*{\prechapternum}{\chapnamefont\MakeUppercase{Chapter}}
  \renewcommand*{\postchapternum}{}
   \renewcommand*{\chapternamenum}{}
  \setlength{\beforechapskip}{18mm}%  \numberheight
  \setlength{\midchapskip}{\paperwidth}% \barlength
  \addtolength{\midchapskip}{-\textwidth}
  \addtolength{\midchapskip}{-\spinemargin}
   \renewcommand*{\printchapternum}{%
     \makebox[0pt][l]{%
       \hspace{.8em}%
       \resizebox{!}{\beforechapskip}{\chapnumfont \thechapter}%
       \hspace{.8em}%
       \rule{\midchapskip}{\beforechapskip}%
     }%
   }%
   \makeoddfoot{plain}{}{}{\thepage}}

\makechapterstyle{obverville}{%
 % \chapterstyle{default}
  \setlength{\beforechapskip}{0pt}
%  \renewcommand*{\printchaptername}{}
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\printchapternum}{%
    \hrule \vskip 0.5\onelineskip
    \Huge \centering \thechapter.\ }
  \renewcommand*{\printchapternonum}{%
    \hrule \vskip 0.5\onelineskip
    \Huge \centering}
  \renewcommand*{\afterchapternum}{}
  \setlength{\midchapskip}{0pt}
  \renewcommand*{\printchaptertitle}[1]{%
    ##1 \par
    \vskip 0.5\onelineskip
   \hrule}}

\makechapterstyle{obcrosshead}{%
  \setlength{\beforechapskip}{2\onelineskip}%
  \renewcommand*{\chapterheadstart}{\vspace{\beforechapskip}}%
  \setlength{\afterchapskip}{2\onelineskip \@plus .2\onelineskip
                             \@minus 0.2\onelineskip}%
%  \renewcommand*{\printchaptername}{}%
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}%
  \renewcommand*{\chapnumfont}{\normalfont\LARGE\bfseries}%
  \renewcommand*{\chaptitlefont}{\chapnumfont}%
  \renewcommand*{\printchapternum}{%
    \centering\chapnumfont \thechapter\quad}%
  \renewcommand{\afterchapternum}{}%
  \renewcommand*{\printchapternonum}{\centering}}

\makechapterstyle{obdowding}{%
  \setlength{\beforechapskip}{2\onelineskip}%
  \setlength{\afterchapskip}{1.5\onelineskip \@plus .1\onelineskip
                            \@minus 0.167\onelineskip}%
  \renewcommand*{\chapnamefont}{\normalfont}%
  \renewcommand*{\chapnumfont}{\chapnamefont}%
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\printchapternum}{\centering\chapnumfont \ifanappendix \thechapter
                 \else \numtoName{\c@chapter}\fi}%
  \renewcommand*{\chaptitlefont}{\normalfont\itshape\huge\centering}%
  \renewcommand*{\printchapternonum}{%
    \vphantom{\printchaptername}\vskip\midchapskip}}

\makechapterstyle{obkomalike}{%
  \setlength{\beforechapskip}{2\onelineskip}%
  \setlength{\afterchapskip}{1.5\onelineskip \@plus .1\onelineskip
                             \@minus 0.167\onelineskip}%
%  \renewcommand*{\printchaptername}{}%
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}%
  \renewcommand*{\chapnumfont}{\normalfont\LARGE\sffamily\bfseries}%
  \renewcommand*{\printchapternum}{\chapnumfont \thechapter\space\space}%
  \renewcommand*{\afterchapternum}{}%
  \renewcommand*{\chaptitlefont}{\normalfont\LARGE\sffamily\bfseries}}

\makechapterstyle{obntglike}{%
  \setlength{\beforechapskip}{50pt \@plus 20pt}%
  \renewcommand*{\chapnamefont}{\normalfont\Large\bfseries}%
  \renewcommand*{\chapnumfont}{\normalfont\Large\bfseries}%
  \renewcommand*{\chaptitlefont}{\normalfont\Large\bfseries}}

\makechapterstyle{obtandh}{%
  \setlength{\beforechapskip}{1\onelineskip}%
  \setlength{\afterchapskip}{2\onelineskip \@plus .1\onelineskip
                            \@minus 0.167\onelineskip}%
%  \renewcommand*{\printchaptername}{}%
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}%
  \renewcommand*{\chapnumfont}{\normalfont\huge\bfseries}%
  \renewcommand*{\printchapternum}{\chapnumfont \thechapter\quad}%
  \renewcommand*{\afterchapternum}{}%
%%%  \renewcommand*{\chaptitlefont}{\chapnumfont\raggedright}}
  \renewcommand*{\chaptitlefont}{\chapnumfont\memRTLraggedright}}

\makechapterstyle{obwilsondob}{%
  \setlength{\beforechapskip}{2\onelineskip}%
  \setlength{\afterchapskip}{4\onelineskip \@plus .1\onelineskip
                             \@minus 0.167\onelineskip}%
%  \renewcommand*{\printchaptername}{}%
  \renewcommand*{\prechapternum}{}
  \renewcommand*{\postchapternum}{}
  \renewcommand*{\chapternamenum}{}%
  \renewcommand*{\chapnumfont}{\normalfont\Huge\itshape}%
  \renewcommand*{\printchapternum}{\raggedleft\chapnumfont \thechapter\quad}%
  \renewcommand*{\afterchapternum}{}%
  \renewcommand*{\chaptitlefont}{\chapnumfont}%
  \renewcommand*{\printchapternonum}{\raggedleft}}

\ExplSyntaxOn
\NewDocumentCommand \apptoobchapterstyle { m m }
{
	\expandafter \apptocmd \cs:w chs@#1 \cs_end: { #2 } {} {}
}
\ExplSyntaxOff

\endinput
