pdfpc

pdfpc is a "presenter console with multi-monitor support for PDF-files". That means, you can use it to display slides in the form of PDF-pages and also have some of the nice features known from, for example, PowerPoint. Check out their website to learn more.

When pdfpc is provided a special .pdfpc file containing some JSON data, it can use that to enhance the user experience by correctly handling overlay slides, displaying speaker notes, setting up a specific timer, and more. While you can write this file by hand or use the pdfpc-internal features to edit it, some might find it more convenient to have all data about their presentation in one place, i.e. the Typst source file. Polylux allows you to do that.

Adding metadata to the Typst source

Polylux exports the pdfpc module that comes with a bunch of useful functions that do not actually add any content to the produced PDF but instead insert metadata that can later be extracted from the document.

Speaker notes

This is possibly the most useful feature of pdfpc. Using the function #pdfpc.speaker-note inside a slide, you can add a note to that slide that will only be visible to the speaker in pdfpc. It accepts either a string:

#pdfpc.speaker-note("This is a note that only the speaker will see.")

or a raw block:

#pdfpc.speaker-note(
  ```md
  # My notes
  Did you know that pdfpc supports Markdown notes? _So cool!_
  ```
)

Note that you can only specify one note per slide (only the first one will survive if you use more than one.)

End slide

Sometimes the last slide in your presentation is not really the one you want to end with. Say, you have some bibliography or appendix for the sake of completeness after your "I thank my mom and everyone who believed in me"-slide.

With a simple pdfpc.end-slide inside any slide you can tell pdfpc that this is the last slide you usually want to show and hitting the End key will jump there.

Save a slide

Similarly, there is a feature in pdfpc to bookmark a specific slide (and you can jump to it using Shift + M). In your Typst source, you can choose that slide by putting pdfpc.save-slide inside it.

Hide slides

If you want to keep a certain slide in your presentation (just in case) but don't normally intend to show it, you can hide it inside pdfpc. It will be skipped during the presentation but it is still available in the overview. You can use pdfpc.hidden-slide in your Typst source to mark a slide as hidden.

Configure pdfpc

The previous commands are all supposed to be used inside a slide. To perform some additional global configuration, you can use pdfpc.config() before any of the slides (it will not be recognised otherwise).

It accepts the following optional keyword arguments:

• duration-minutes: how many minutes (a number) the presentation is supposed to take, affects the timer in pdfpc

• start-time: wall-clock time when the presentation is supposed to start, either as a datetime(hour: ..., minute: ..., second: ...) or as a string in the HH:MM format

• end-time: same as start-time but when the presentation is supposed to end

• last-minutes: how many minutes (a number) before the time runs out the timer is supposed to change its colour as a warning

• note-font-size: the font size (a number) the speaker notes are displayed in

• disable-markdown: whether or not to disable rendering the notes as markdown (a bool), default false

• default-transition: the transition to use between subsequent slides, must be given as a dictionary with (potentially) the following keys:

  • type: one of "replace" (default), "push", "blinds", "box", "cover", "dissolve", "fade", "glitter", "split", "uncover", "wipe"
  • duration-seconds: the duration of the transition in seconds (a number)
  • angle: in which angle the transition moves, one of ltr, rtl, ttb, and btt (see the #stack function)
  • alignment: whether the transition is performed horizontally or vertically, one of "horizontal" and "vertical"
  • direction: whether the transition is performed inward or outward, one of "inward" and "outward"

  Not all combinations of values are necessary or make sense for all transitions, of course.

Extracting the data: polylux2pdfpc

As mentioned above, the functions from the pdfpc module don't alter the produced PDF itself. Instead, we need some other way to extract their data. You could, in principle, do that by hand using the typst query CLI and then assemble the correct .pdfpc file yourself. However, this tedious task is better solved by the polylux2pdfpc tool.

Installation

If you have Rust installed, you can simply run

cargo install --git https://github.com/andreasKroepelin/polylux/ --branch release

If you use Arch Linux btw, you can also install polylux2pdfpc from the AUR package polylux2pdfpc-git (thank you to Julius Freudenberger!)

Usage

You invoke polylux2pdfpc with the same arguments you would also give to typst compile when you wanted to build your slides. For example, say you have a file called talk.typ in the folder thesis that has some global utility files or so, you would compile it using

typst compile --root .. thesis/talk.typ

and extract the pdfpc data using

polylux2pdfpc --root .. thesis/talk.typ

Internally, polylux2pdfpc runs typst query, collects all the pdfpc-related metadata and then writes a .pdfpc file that equals the input file up to the suffix. In our example with thesis/talk.typ, we obtain thesis/talk.pdfpc. Since typst compile produced thesis/talk.pdf, you can now simply open the PDF in pdpfc:

pdfpc thesis/talk.pdf

and it will automatically recognise the .pdfpc file.