% This is part of the OpTeX project, see http://petr.olsak.net/optex
\_codedecl \slideshow {Slides style for OpTeX <2025-02-27>} % loaded on demand by \slides
\_doc -----------------------------
Default margins and design is declared here.
The `\_ttfont` is scaled by `mag1.15` in order to balance the
ex height of Helvetica (Heros) and LM fonts Typewriter.
The `\begtt`...`\endtt` verbatim is printed by smaller text.
\_cod -----------------------------
\_margins/1 a5l (14,14,10,3)mm % landscape A5 format
\_def\_wideformat{\_margins/1 (263,148) (16,16,10,3)mm } % 16:9 format
\_ifx\_fontnamegen\_undefined \_fontfam[Heros]
\_let\_ttfont=\_undefined \_famvardef\_ttfont{\_setfontsize{mag1.15}\_tt}
\_fi
\_typosize[16/19]
\_def\_urlfont{}
\_everytt={\_typosize[13/16] \_advance\_hsize by10mm}
\_fontdef\_fixbf{\_bf}
\_nopagenumbers
\_parindent=0pt
\_ttindent=5mm
\_parskip=5pt plus 4pt minus2pt
\_rightskip=0pt plus 1fil
\_ttindent=10pt
\_def\_ttskip{\_smallskip}
\_let\_scolor=\Blue % secondary color used in default design
\_onlyrgb % RGB color space is better for presentations
\_doc -----------------------------
The bottom margin is set to 3\,mm. If we use 1\,mm, then the baseline of
`\footline` is 2\,mm from the bottom page. This is the depth of the `\Grey`
rectangle used for page numbers. It is r-lapped to `\hoffset` width because left
margin = `\hoffset` = right margin. It is 14\,mm for narrow pages or
16\,mm for wide pages.
\_cod -----------------------------
\_footlinedist=1mm
\_footline={\_hss \_rlap{%
\_rlap{\Grey\_kern.2\_hoffset\_vrule height6mm depth2mm width.8\_hoffset}%
\_hbox to\_hoffset{\White\_hss\_folio\_kern3mm}}}
\_doc -----------------------------
The \`\subtit` is defined analogically like `\tit`.
\_cod -----------------------------
\_eoldef\_subtit#1{\_vskip20pt {\_leftskip=0pt plus1fill \_rightskip=\_leftskip
\_subtitfont #1\_nbpar}}
\_doc -----------------------------
The \`\pshow``<num>` prints the text in invisible
(transparent) font when \^`\layernum`\code{<}`<num>`.
For transparency we need to define special graphics states.
\_cod -----------------------------
\_def\_Transparent {\_transparency255 }
\_public \Transparent ;
\_def\_use#1#2{\_ifnum\_layernum#1\_relax#2\_fi}
\_def\_pshow#1{\_use{=#1}\Red \_use{<#1}\_Transparent \_ignorespaces}
\_doc -----------------------------
The main level list of items is activated here. The `\_item:X` and
`\_item:x` are used and are re-defined here.
If we are in a nested level of items and `\pg+` is used then
`\egroups` macro expands to the right number of `\egroup`s
to close the page correctly. The level of nested item lists
is saved to the `\_ilevel` register and used when we start again
the next text after `\pg+`.
\_cod -----------------------------
\_newcount\_gilevel
\_def\*{*}
\_adef*{\_relax\_ifmmode*\_else\_ea\_startitem\_fi} % defined also in styles.opm
\_sdef{_item:X}{\_scolor\_raise.2ex\_fullrectangle{.8ex}\_kern.5em}
\_sdef{_item:x}{\_scolor\_raise.3ex\_fullrectangle{.6ex}\_kern.4em}
\_style X
\_def\_egroups{\_par\_global\_gilevel=\_ilevel \_egroup}
\_everylist={\_novspaces \_ifcase\_ilevel \_or \_style x \_else \_style - \_fi
\_addto\_egroups{\_egroup}}
\_doc -----------------------------
The default values of \`\pg`, i.\,e.\ `\pg;`, `\pg+` and `\pg.` are very simple.
They are used when `\slideshow` is not specified.
\_cod -----------------------------
\_def\_pg#1{\_cs{_spg:#1}}
\_sdef{_spg:;}{\_vfil\_break \_lfnotenumreset}
\_sdef{_spg:.}{\_endslides}
\_sdef{_spg:+}{\_par}
\_doc -----------------------------
The \`\_endslides` is defined as `\_end` primitive (preceded by `\_byehook`), but
slide-designer can redefine it. For example,
\ulink[http://petr.olsak.net/optex/optex-tricks.html\#slider]{OpTeX trick 0029}
shows how to define clickable navigation to the pages and how to check
the data integrity at the end of the document using `\_endslides`.
The `\bye` macro is redefined here as an alternative to `\pg.`.
\_cod -----------------------------
\_def\_endslides{\_vfill \_supereject \_byehook \_end}
\_def\bye{\_pg.}
\_doc -----------------------------
We need no numbers and no table of contents when using slides.
The \^`\_printsec` macro is redefined in order the title is centered
and typeset in `\_scolor`.
\_cod -----------------------------
\_def\_titfont{\_typosize[42/60]\_boldify \_scolor}
\_def\_subtitfont{\_typosize[20/30]\_boldify}
\_def\_secfont{\_typosize[25/30]\_boldify \_scolor}
\_nonum \_notoc \_let\_resetnonumnotoc=\_relax
\_def\_printsec#1{\_par
\_abovetitle{\_penalty-400}\_bigskip
{\_secfont \_noindent \_leftskip=0pt plus1fill \_rightskip=\_leftskip
\_printrefnum[@\_quad]#1\_nbpar}\_insertmark{#1}%
\_nobreak \_belowtitle{\_medskip}%
}
\_doc -----------------------------
When \`\slideshow` is active then each page is opened
by `\setbox\_slidepage=\vbox\bgroup` (roughly speaking)
and closed by `\egroup`. The material is
`\unvbox`ed and saved for the usage in the next usage if `\pg+` is in process.
The \`\_slidelayer` is incremented instead `\pageno` if `\pg+`.
This counter is equal to `\count1`, so it is printed to the terminal and
log file next to `\pageno`.
The code is somewhat more complicated when \^`\layers` is used. Then
`<layered-text>` is saved to the \`\_layertext` macro, the material before
it is in \`\_slidepage` box and the material after it is in \`\_slidepageB`
box. The pages are completed in the `\loop` which increments the
\`\layernum` register and prints page by the \`\_printlayers`
\_cod -----------------------------
\_newbox\_slidepage \_newbox\_slidepageB
\_countdef\_slidelayer=1
\_def\_slideshow{\_slidelayer=1 \_slideshowactive
\_let\slideopen=\_relax % first wins
\_setbox\_slidepage=\_vbox\_bgroup\_bgroup}
\_def\_slideshowactive{%
\_sdef{_spg:;}{\_closepage \_global\_slidelayer=1 \_resetpage \_openslide}
\_sdef{_spg:.}{\_closepage \_endslides}
\_sdef{_spg:+}{\_closepage \_incr\_slidelayer \_decr\_pageno \_openslide}
\_let\_layers=\_layersactive
\_slidelinks % to prevent hyperlink-dests duplication
}
\_def\_openslide{\_setbox\_slidepage=\_vbox\_bgroup\_bgroup \_setilevel
\_ifvoid\_slidepage \_else \_unvbox\_slidepage \_nointerlineskip\_lastbox \_fi}
\_def\_setilevel{\_loop \_decr\_gilevel \_ifnum\_gilevel<0 \_else \_begitems \_repeat}
\_def\_closepage{\_egroups \_egroup
\_ifnum \_maxlayers=0 \_unvcopy\_slidepage \_vfil\_break
\_else \_begingroup \_setwarnslides \_layernum=0
\_loop
\_ifnum\_layernum<\_maxlayers \_advance\_layernum by1
\_printlayers \_vfil\_break
\_ifnum\_layernum<\_maxlayers \_incr\_slidelayer \_decr\_pageno \_fi
\_repeat
\_global\_maxlayers=0
\_incr\_layernum \_global\_setbox\_slidepage=\_vbox{\_printlayers}%
\_endgroup
\_fi}
\_def\_resetpage{%
\_global\_setbox\_slidepage=\_box\_voidbox \_global\_setbox\_slidepageB=\_box\_voidbox
\_lfnotenumreset
}
\_def\_setwarnslides{%
\_def\pg##1{\_opwarning{\_string\pg##1 \_layersenv}\_def\pg####1{}}%
\_def\layers##1 {\_opwarning{\_string\layers\_space \_layersenv}\_def\layers####1{}}%
}
\_def\_layersenv{cannot be inside \_string\layers...\_string\endlayers, ignored}
\_def\_printlayers{\_unvcopy\_slidepage \_prevdepth=\_dp\_slidepage
{\_layertext \_endgraf}%
\_vskip\_parskip
\_unvcopy\_slidepageB
}
\_let\_destboxori=\_destbox
\_newcount\_layernum \_newcount\_maxlayers
\_maxlayers=0
\_long\_def\_layersactive #1 #2\endlayers{%
\_par\_penalty0\_egroup\_egroup
\_gdef\_layertext{\_settinglayer#2}%
\_global\_maxlayers=#1
\_setbox\_slidepageB=\_vbox\_bgroup\_bgroup
\_setbox0=\_vbox{{\_layernum=1 \_globaldefs=-1 \_layertext\_endgraf}}\_prevdepth=\_dp0
}
\_public \subtit \slideshow \pg \wideformat \use \pshow \layernum ;
\_doc -----------------------------
\`\slideopen` should be used instead \^`\slideshow` to deactivate it
but keep the borders of groups.
\_cod -----------------------------
\_def\_slideopen{\_let\slideshow=\_relax % first wins
\_sdef{_spg:;}{\_egroups\_vfil\_break \_lfnotenumreset\_bgroup \_setilevel}
\_sdef{_spg:.}{\_egroups\_endslides}
\_sdef{_spg:+}{\_egroups\_bgroup \_setilevel}
\_let\_layersopen=\_egroup \_let\_layersclose\_bgroup
\_bgroup
}
\_public \slideopen ;
\_doc -----------------------------
When \^`\slideshow` is active then the destinations of internal hyperlinks
cannot be duplicated to more \"virtual" pages because
hyperlink destinations have to be unique in the whole document.
The \^`\slideshow` creates boxes of typesetting material and copies them to
more pages. So, we have to suppress creating destinations in these boxes.
This is done in the \`\_slidelinks` macro. We
can move creating these destinations to the output routine. \`\_sdestbox` is
saved value of the original `\_destbox` which is redefined to do only
`\addto\_destboxes{\_sdestbox[<label>]}`. All destinations saved to
\`\_destboxes` are created at the start of the next output routine in the
\^`\_pagedest` macro. The output routine removes `\_destboxes`, so each
destination is created only once.
Limitations of this solution: destinations are only at the start of the
page, no at the real place where \^`\wlabel` was used. The first \"virtual"
page where \^`\wlabel` is used includes its destination. If you want to
go to the final page of the partially uncovering ideas then
use \^`\label``[<label>]`\^`\wlabel``{text}` in the last part of
the page (before `\pg;`) o use \^`\pgref` instead \^`\ref`.
\_cod -----------------------------
\_def\_slidelinks{%
\_def \_destbox[##1]{\_edef\_tmp{\_noexpand\_sdestbox[##1]}%
\_global\_ea\_addto\_ea\_destboxes\_ea{\_tmp}}%
\_def \_pagedest {%
\_hbox{\_def\_destheight{25pt}\_sdestbox[pg:\_the\_gpageno]\_destboxes}%
\_nointerlineskip \_gdef\_destboxes{}%
}%
\_ifx \_dest\_destactive \_else \_let\_pagedest=\_relax \_fi
}
\_let\_sdestbox = \_destbox
\_def\_destboxes{} % initial value of \_destboxes
\_let\_bibgl=\_global % \advance\bibnum must be global if they are at more pages
\_doc -----------------------------
The \`\_settinglayer` is used in the \^`\_layertext` macro to prevent
printing \"Duplicate label" warning when it is expanded. It is done
by special value of \`\_slideshook` (used by the \^`\label` macro).
Moreower, the warning about illegal use of `\bib`, `\usebib` in `\layers`
environment is activated.
\_cod -----------------------------
\_def\_settinglayer{%
\_def\_slideshook ##1##2{}%
\_def\_bibB[##1]{\_nousebib}\_def\_usebib/##1 (##2) ##3 {\_nousebib}%
}
\_def\_nousebib{\_opwarning{Don't use \noexpand\bib nor \noexpand\usebib in \string\layers}}
\_doc -----------------------------
Default \`\layers` `<num>` macro (when \^`\slideshow` is not activated) is simple.
It prints the `<layered-text>` with `\layernum=<num>+1` because we need the
result after last layer is processed.
\_cod -----------------------------
\_long\_def\_layers #1 #2\endlayers{\_par
\_layersopen {\_layernum=\_numexpr#1+1\_relax #2\_endgraf}\_layersclose}
\_let\_layersopen=\_relax
\_let\_layersclose=\_relax
\_def\layers{\_layers}
\_doc -----------------------------
We must to redefine \^`\fnotenumpages` because the data from `.ref` file
are less usable for implementing such a feature: the
footnote should be in more layers repeatedly. But we can suppose that
each page starts by `\pg;` macro, so we can reset the footnote counter by
this macro.
\_cod -----------------------------
\_def \_fnotenumpages {\_def\_fnotenum{\_the\_lfnotenum}\_pgfnotefalse
\_def\_lfnotenumreset{\_global\_lfnotenum=0 }}
\_let \_lfnotenumreset=\_relax
\_public \fnotenumpages ;
\_endcode % ----------------------------------------------
The user manual of \OpTeX/ slides are in `op-slides.tex` file.
2025-02-27 \boldify added to \sec/titfont, bug fixed
2022-05-12 \Blue -> \_scolor, user can re-define it
2022-03-08 \Transparent re-defined, \Visible, \Invisible removed
2022-03-05 \_addextgstate: new syntax used
2022-03-03 \supereject in \_endslides before \_byehook added
2021-04-22 \adef* moved back, bug fixed in more-macros.opm
2021-04-21 \adef* removed from slides.opm, bug fixed
2021-04-19 \_byehook added to \_endslides.
2021-04-13 hyperlinks destinations are moved to the output routine when \slideshow
2021-04-10 \layers: \prevdepth calculation added, {\_layertext} group added
2021-04-10 \layers: bug with \setbox\_slidepageB fixed
2021-04-10 \layers: \vskip\parskip added after \unvcopy\_slidepage
2021-03-10 \slideopen introduced, bug with colors in \setbox fixed
2021-03-10 \ifmmode* added to \adef*
2021-02-15 \_def\_decr removed
2021-01-16 \layers at empty page raises error: problem fixed
2020-03-19 slides introduced