# ltx-talk port

This branch is the presentation template ported from beamer to the
[ltx-talk](https://github.com/josephwright/ltx-talk) class. ltx-talk was
written with tagging as a design goal.

## Requirements

  * LuaLaTeX
  * TeX Live 2025 or newer (ltx-talk needs LaTeX 2025-11-01 or later);
    `texlive-latex-recommended` ships the class
  * `python3-pypdf`, for assembling the notes PDF

You can install all three on Debian with:

```
apt install texlive-latex-recommended python3-pypdf
```

## Building

```
make slides      # the deck; this is what gets uploaded
make notes       # double-width slide + notes pages for presenting
make pdfpc       # build the notes PDF and open it in pdfpc
```

The notes are a kludge. They exist to be read while talking and not shared.
Only the slides build is expected to validate with tools like
[veraPDF](https://verapdf.org/).

## Speaker notes

ltx-talk has no `\note` command. Its README and website list speaker notes
among what the class is for, but the feature is unwritten (see
[issue #156](https://github.com/josephwright/ltx-talk/issues/156)).

`talk-notes.sty` defines `\note` so that it records its text to a side file and
contributes nothing to the slides. `mknotes` reads that file afterwards and
builds the presenter PDF.

The assembled page puts the slide on the left and, on the right, a grey band
carrying the section and position in the talk, a thumbnail of the current
slide flush into the corner, and the notes below. Previous and next slides are
left to the viewer: [dspdfviewer](https://github.com/dannyedel/dspdfviewer),
[pdfpc](https://pdfpc.github.io/), or the web viewers
[Beamer Viewer](https://beamerviewer.euxane.eu/) and
[backstage](https://bckstg.xyz/).

### Installing speaker notes

To use speaker notes in another ltx-talk document, copy two files out of this
repository:

- `mknotes`
- `talk-notes.sty`

Load the package in the preamble:

```latex
\usepackage{talk-notes}
```

Write notes with `\note{...}`, or `\note<2->{...}` to bind one to particular
slides of a frame. As in beamer, plain notes run together as text, each
starting a new paragraph, and `\note[item]{...}` adds an entry to a numbered
list printed after them.

Build the deck, then assemble the presenter PDF:

```
./mknotes example
```

That reads `example.pdf` and `example.notes` and writes `example-notes.pdf`,
the double-width version you present from. The slides in `example.pdf` are
untouched.

If `fonts.tex` is present it is used for the notes pages, so they match the
deck. `--preamble FILE` names a different fragment.

## Theme

`trantor.sty` is [Marco Pompili's](https://github.com/mrc-pop)
[Metropolis-like theme](https://github.com/mrc-pop/trantor) for
ltx-talk.

## Known gaps

Frame titles must be given as `\frametitle{...}` inside the frame, not as the
argument to `\begin{frame}{...}`. Only the command form is tagged.

ltx-talk tags frame titles at H4, well below sections, and its manual calls the
relationship between frame titles and sectioning "still very much open".

[Issue #33](https://github.com/josephwright/ltx-talk/issues/33): `\only<1>` and
`\only<2>` produce output that fails validation. The `\pause` and `<+->` forms
used here are unaffected.

ltx-talk is version 0.5.x and warns that almost all interfaces may change.
`talk-notes.sty` reads two internals, `\g__talk_frame_int` and
`\g__talk_slide_int` — the first thing to check if a release breaks the notes
build.