path: root/Master/texmf-dist/tex/luatex/optex/sections.opm

%% This is part of OpTeX project, see http://petr.olsak.net/optex

\_codedecl \chap {Titles, chapters, sections, subsections <2020-03-14>} % preloaded in format

   \_doc ---------------------------
   We are using scaled fonts for titles. They are scaled from main fonts size
   of the document, which is declared by first `\typosize[<fo-size>/<b-size>]`
   command. 
   \_cod ---------------------------

\_def \_titfont  {\_scalemain\_boldify\_typoscale[\_magstep4/\_magstep5]}
\_def \_chapfont {\_scalemain\_boldify\_typoscale[\_magstep3/\_magstep3]}
\_def \_secfont  {\_scalemain\_boldify\_typoscale[\_magstep2/\_magstep2]}
\_def \_seccfont {\_scalemain\_boldify\_typoscale[\_magstep1/\_magstep1]}

   \_doc ---------------------------
   The `\tit` macro is defined by `\eoldef`, it means that the parameter is
   separated by end of line. The macros `\chap`, `\sec` and `\secc` use
   `\eoldef` too.
   \_cod ---------------------------

\_eoldef\_tit #1{\_vglue\_titskip
  {\_leftskip=0pt plus1fill \_rightskip=\_leftskip % centering
   \_titfont \_noindent #1\_par}%
   \_nobreak\_bigskip
}
\_public \tit ;

   \_doc ---------------------------
   You can re-define `\_printchap`, `\_printsec` or `\_printsecc` macros if 
   another design of section titles is needed. These macros gets the <title>
   text in its parameter. The common recommendations for these macros are:
   \begitems
   * Use `\_abovetitle{<penaltyA>}{<skipA>}` and `\_belowtitle{<skipB>}
     for inserting vertical material above and below the section title.
     The arguments of these macros are normally used, i.e. \_abovetitle`
     inserts <penaltyA><skipA> and `\_belowtitle` inserts <skipB>. 
     But there is an
     exception: if `\_belowtitle{<skip>}` is immediately followed by next
     `\_abovetitle{<penalty>}` (for example section title is immediately followed by
     subsection title), then only <skipA> is generated, i.e.
     <skipB><penaltyA><skipA> is reduced only to <skipA>
     The reason of such behavior: we don't want to duplicate vertical skip 
     and we don't want to use negative penalty in such cases.
     Moreower, `\_abovetitle{<penaltyA>}{<skipA>}` takes previous whatever
     vertical skip (other than from `\_belowtitle`) and generates only 
     greater from this pair of skips. I.e.  <whatever-skip><penaltyA><skipA> 
     is reduced to $<penaltyA>\max(<whatever-skip><skipA>)$. 
     The reason of such behavior: we don't want to
     duplicate vertical skips (from `\_belowlistskip`, for example) above the title.
   * Use `\_printrefnum[<pre>@<post>]` in horizontal mode. It prints 
     <pre><ref-num><post>. The <ref-num> is `\thechapnum` or `\thesecnum`
     or `\theseccnum` depending on what type o title is processed.
     If `\nonum` prefix is used then `\_printrefnum` prints nothing. 
     The macro `\_printrefnum` does more work: it creates destination of hyperlinks 
     (if `\hyperlinks{}{}` is used) and saves references from label (if
     `\label[<label>]` precedes) and saves references for table of contents
     (if `\maketoc` is used).
   * Use `\nbpar` for closing the paragraph for printing title. This
     command inserts `\_nobreak` between each line of such paragraph, so
     the title cannot be broken to more pages. 
   \enditems
   \_cod ---------------------------

\_def\_printchap #1{\_vfill\_supereject
   {\_chapfont \_noindent \_mtext{chap} \_printrefnum[@]\_par
    \_nobreak\_smallskip
    \_noindent \_raggedright #1\_nbpar}\_mark{}%
   \_nobreak \_belowtitle{\_medskip}% 
   \_firstnoindent
}
\_def\_printsec#1{\_par 
   \_abovetitle{\_penalty-400}\_bigskip
   {\_secfont \_noindent \_raggedright \_printrefnum[@\_quad]#1\_nbpar}\_insertmark{#1}%
   \_nobreak \_belowtitle{\_medskip}% 
   \_firstnoindent
}
\_def\_printsecc#1{\_par 
   \_abovetitle{\_penalty-200}\_medskip 
   {\_seccfont \_noindent \_raggedright \_printrefnum[@\_quad]#1\_nbpar}%
   \_nobreak \_belowtitle{\_medskip}% 
   \_firstnoindent
}

   \_doc --------------------------
   The `\_sectionlevel` is the level of the printed section:
   \begitems
   * `\_sectionlevel=0` -- reserved for parts of the book (unused by default)
   * `\_sectionlevel=1` -- chapters (used in `\chap`)
   * `\_sectionlevel=2` -- sections (used in `\sec`)
   * `\_sectionlevel=3` -- subsections (used in `\secc`)
   * `\_sectionlevel=4` -- subsubsections (unused by default)
   \enditems
   \_cod --------------------------

\_newcount\_sectionlevel
\_def \_secinfo {\_ifcase \_sectionlevel
   part\_or chap\_or sec\_or secc\_or seccc\_fi
}

   \_doc --------------------------
   The `\_chapx` initializes counters used in chapters, 
   the `\_secx` initializes counters in sections
   and `\_seccx` initializes counters in subsections.
   If you have another concept of numbering objects used in your 
   document, you can re-define these macros. All settings here are global
   because it is used by `{\_globaldefs=1 \_chapx}`.

   Default concept: Tables, figuers and display maths are numbered
   from one in each section -- subsetions doesn't reset these counters.

   The `\_the*` macros includes the format of numbers used when the object
   is printing. If chapter is never used in the document then `\_chapnum=0`
   and `\_othe\_chapnum.` expands to empty. Sections have numbers <num> and
   subsections <num>.<num>. On the other hand, if chapter is used in the
   document then `\_chapnum>0` and sections have numbers <num>.<num> 
   and subsections have numbers <num>.<num>.<num>. 

   If you have more types of numbered objects in your document then you can
   declare appropriate counters and do `\addto\_chapx{\yourcounter=0 }` 
   for example.
   \_cod --------------------------

\_newcount \_chapnum  % chapters 
\_newcount \_secnum   % sections
\_newcount \_seccnum  % subsections
\_newcount \_tnum     % table numbers
\_newcount \_fnum     % figure numbers
\_newcount \_dnum     % numbered display maths

\_def \_chapx {\_incr\_chapnum \_secnum=0 \_seccnum=0 \_tnum=0 \_fnum=0 \_dnum=0 \_lfnotenum=0 }
\_def \_secx  {\_incr\_secnum             \_seccnum=0 \_tnum=0 \_fnum=0 \_dnum=0 }
\_def \_seccx {\_incr\_seccnum } 

\_def \_thechapnum {\_the\_chapnum}
\_def \_thesecnum  {\_othe\_chapnum.\_the\_secnum}
\_def \_theseccnum {\_othe\_chapnum.\_the\_secnum.\_the\_seccnum}
\_def \_thetnum    {\_othe\_chapnum.\_the\_secnum.\_the\_tnum}
\_def \_thefnum    {\_othe\_chapnum.\_the\_secnum.\_the\_fnum}
\_def \_thednum    {(\_the\_dnum)}

\_def\_othe #1.{\_ifnum#1>0 \_the#1.\_fi}
\_def\_incr #1{\_global\_advance#1by1 }

   \_doc ----------------------------
   The `\notoc` and `\nonum` prefixes are implemented by
   internal `\_ifnotoc` and `\_ifnonum`.
   \_cod ----------------------------

\_newifi \_ifnotoc  \_notocfalse  \_def\_notoc {\_global\_notoctrue}
\_newifi \_ifnonum  \_nonumfalse  \_def\_nonum {\_global\_nonumtrue}
\_def \_resetnonumnotoc{\_global\_notocfalse \_global\_nonumfalse}
\_public \notoc \nonum ;

   \_doc ----------------------------
   The `\chap`, `\sec` and `\secc` macros are implemnted here.
   The `\_inchap`, `\_insec` and `\_insecc` macros does the real work,
   First, we read the optional parameter `[<label>]`, if it exists.
   \_cod ----------------------------

\_optdef\_chap[]{\_trylabel \_inchap}
\_optdef\_sec []{\_trylabel \_insec}
\_optdef\_secc[]{\_trylabel \_insecc}
\_def\_trylabel{\_istoksempty\_opt\_iffalse \_label[\_the\_opt]\_fi}

\_eoldef\_inchap #1{\_par \_sectionlevel=1
   \_def \_savedtitle {#1}% saved to .ref file
   \_ifnonum \_else {\_globaldefs=1 \_chapx}\_fi
   \_edef \_therefnum {\_ifnonum \_space \_else \_thechapnum \_fi}%
   \_printchap{#1}%
   \_resetnonumnotoc
}
\_eoldef\_insec #1{\_par \_sectionlevel=2
   \_def \_savedtitle {#1}% saved to .ref file
   \_ifnonum \_else {\_globaldefs=1 \_secx}\_fi
   \_edef \_therefnum {\_ifnonum \_space \_else \_thesecnum \_fi}%
   \_printsec{#1}%
   \_resetnonumnotoc
}
\_eoldef\_insecc #1{\_par \_sectionlevel=3
   \_def \_savedtitle {#1}% saved to .ref file
   \_ifnonum \_else {\_globaldefs=1 \_seccx}\_fi
   \_edef \_therefnum {\_ifnonum \_space \_else \_theseccnum \_fi}%
   \_printsecc{#1}%
   \_resetnonumnotoc
}
\_public \chap \sec \secc ;

   \_doc ----------------------------
   The `\_printrefnum[<pre>@<post>]` macro is used in `\_print*` macros.
   The `\_wtotoc {<level>}{<info>}{<ref-num>}{<title-text>}`
   macro expands its parameters and does `\_wref`.

   Note that the <tite-text> is `\detokenize`d before `\wref`, so the 
   problem of \"fragile macros" from old \LaTeX/ never occurrs. 
   \_cod ----------------------------

\_def \_printrefnum [#1@#2]{\_leavevmode % we must be in horizontal mode
   \_ifnonum \_else #1\_therefnum #2\_fi
   \_wlabel \_therefnum  % references, if `\label[<label>]` is declared 
   \_ifnotoc \_else \_incr \_tocrefnum
       \_dest[toc:\_the\_tocrefnum]%
       \_wtotoc{\_the\_sectionlevel}{\_secinfo}%
               {\_therefnum}{\_detokenize\_ea{\_savedtitle}}%
   \_fi
}
\_def \_wtotoc #1#2#3#4{\_edef\_tmp{{#1}{#2}{#3}{#4}}\_ea\_wtotocA\_tmp}
\_def \_wtotocA #1#2#3#4{\_wref\_Xtoc{{#1}{#2}{#3}{#4}}}

   \_doc -----------------------------
   The `\_abovetitle{<penaltyA>}{<skipA>}` and `\_belowtitle{<skipB>}` pair 
   communicates using a special penalty 11333 in vertical mode. 
   The `\_belowtitle` puts the vertical skip (its value is saved in 
   `\_savedtitleskip`) followed by this special penalty.
   The `\_abovetitle` reads `\lastpenalty` and if it has this special value
   then it removes the skip used before and dont use the parameter.
   The `\abovetitle` creates <skipA> only if whatever previous skip is less
   or equal than <skipA>. We must save <whatever-skip>, remove it,
   create <penaltyA> (if belowtitle does not preceded) and create
   <whatever-skip> or <skipA> depending on what is greater.
   The amount of <skipA> is measured using `\setbox0=\vbox`.
   \_cod -----------------------------

\_newskip \_savedtitleskip  
\_newskip \_savedlastskip
\_def\_abovetitle #1#2{\_savedlastskip=\_lastskip % <whatever-skip>
   \_ifdim\_lastskip>0pt \_vskip-\_lastskip \_fi
   \_ifnum\_lastpenalty=11333 \_vskip-\_savedtitleskip \_else #1\_fi
   \_ifdim\_savedlastskip>0pt \_setbox0=\_vbox{#2\_global\_tmpdim=\_lastskip}%
   \_else \_tmpdim=\_maxdimen \_fi
   \_ifdim\_savedlastskip>\_tmpdim \vskip\_savedlastskip \_else #2\_fi
}
\_def\_belowtitle #1{#1\_global\_savedtitleskip=\_lastskip \_penalty11333 }

   \_doc -----------------------------
   `\nbpar` sets `\interlinepenaty` value.
   `\nl` is \"new line" in text (or titles), but space in toc or healdlines or outlines.
   \_cod -----------------------------

\_def\_nbpar{{\_interlinepenalty=10000\_endgraf}}

\_protected\def\_nl{\hfil\break}
\_regmacro {\def\_nl{\_unskip\_space}} {\def\_nl{\_unskip\_space}} {\def\_nl{ }}
\_regmacro {\def\nl{\_unskip\_space}}  {\def\nl{\_unskip\_space}}  {\def\nl{ }}

\_public \nbpar \nl ;

   \_doc -----------------------------
   `\_firstnoindent` puts a material to `\everypar` in order to next
   paragraph will be without indentation. It is useful after titles.
   If you dislike this feature then you can say `\let\_firtnoindent=\relax`.
   The `\_wipeepar` removes the material from `\everypar`.
   \_cod -----------------------------

\_def \_afternoindent {\_global\_everypar={\_wipeepar \_setbox7=\_lastbox}}
\_def \_wipeepar {\_global\_everypar={}}
\_let \_firstnoindent=\_afternoindent

   \_doc ----------------------------- 
   The `\mark` (for running heads) is used in `\_printsection` only. We
   suppose that chapters will be printed after `\vfil\break`, so user can
   implement chapter titles for running headers directly by macros, no
   `\mark` machanism is needed. But sections need `\mark`s. And they can be
   mixed with chapter's running heads, of course. 

   The `\_insermark{<title text>}` saves `\mark` in the format
   `{<title-num>} {<title-text>}`, so it can be printed \"as is" in
   `\headline` (see the space between them), or you can define a formating
   macro with two parameters for processing these data, if you need it.   
   \_cod -----------------------------

\_def\_insertmark#1{\_mark{{\_ifnonum\_else\_therefnum\_fi} {\_unexpanded{#1}}}}

   \_doc -----------------------------
   \OpTeX/ sets `\headline={}` by default, so no running heads are printed.
   You can activate the running heads by following code, for example:
   \begtt
   \addto \_chapx {\_edef\_runningchap {\_thechapnum: \_unexpanded\_ea{\_savedtitle}}}
   \def \formathead #1#2{\isempty{#1}\iffalse #1: #2\fi}
   \headline = {%
      \ifodd \pageno
          \hfil \ea\formathead\firstmark{}{}%
      \else
          Chapter: \runningchap \hfil
      \fi 
   }
   \endtt

   The `\caption/<letter>` uses `\_<letter>num` counter. 
   The group opened by `\caption` is finalized by first \par from
   empty line or from `\vskip` or from `\endinsert`.
   The `\_printcaption<letter>` is called, it starts with
   printing of the caption.
   \_cod -----------------------------

\_def\_caption/#1{\_def\_tmpa{#1}\_nospaceafter \_capA}
\_optdef\_capA []{\_trylabel \_incaption}
\_def\_incaption {\_bgroup
   \_ifcsname _\_tmpa num\_endcsname \_ea\_incr \_csname _\_tmpa num\_endcsname
   \_else \_opwarning{Unknown caption /\_tmpa}\_fi
   \_edef\_thecapnum {\csname _the\_tmpa num\endcsname}%
   \_edef\_thecaptitle{\_mtext{\_tmpa}}%
   \_ifcsname _everycaption\_tmpa\_endcsname 
       \_ea\_the \_csname _everycaption\_tmpa\_endcsname \_fi
   \_def\_par{\_nbpar\_egroup}\_let\par=\_par
   \_cs{_printcaption\_tmpa}%
}

   \_doc -----------------------------
   The `\_printcaption<letter>` macro starts in vertical mode. It must
   switch to horizontal mode, it must use `\_wlabel\_thecapnum` (in order to
   make reference and hyperlink destination) a it can use:
   \begitems
   * `\_thecaptitle` ... expands to the word Table or Figure (depending on
                         the current language).
   * `\_thecapnum` ... expands to `\the<letter>num` (caption number).
   \enditems
   \_cod -----------------------------

\_def \_printcaptiont {%
   \_noindent \_wlabel\_thecapnum {\_bf\_thecaptitle~\_thecapnum}\_enspace
   \_narrowlastlinecentered\_iindent
}
\_let \_printcaptionf = \_printcaptiont % caption of figures = caption of tables
\_def \_cskip {\_par\_nobreak\_medskip} % space between caption and the object

\_public \caption \cskip ;

   \_doc -----------------------------
   The default format of `\caption` text is paragraph in block narrower by 
   `\_iindent` and with the last line is centered. This setting is done by 
   `\_narrowlastlinecentered` macro. 
   \_cod -----------------------------

\_def\_narrowlastlinecentered#1{%
   \_leftskip=#1plus1fil
   \_rightskip=#1plus-1fil
   \_parfillskip=0pt plus2fil
}

   \_doc -----------------------------
   `\eqmark` is processed in display mode (we add `\eqno` primitive)
   or in internal mode when `\eqaligno` is used (we don't add `\eqno`). 
   \_cod -----------------------------

\_optdef\_eqmark []{\_trylabel \_ineqmark}
\_def\_ineqmark{\_incr\_dnum
  \_ifinner\_else\_eqno \_fi 
  \_wlabel\_thednum \_thednum
}
\_public \eqmark ;

\_endcode % -------------------------------------