PDF export

Experimental

Tuned with Firefox's Save to PDF on A4 landscape. Chromium browsers should work (they follow pdf_aspect exactly, with no letterboxing) but are less tested.

Printing

Enter slide mode with slide_mode_button.
Click the printer button (🖨) in the slide controls.
In the browser's print dialog, choose Save to PDF.

Each slide becomes one page, with its bands, footer and logos. See this example PDF.

Page shape

A slide keeps the browser window's width when printed, so the content has the same scale as on screen. Two keywords of slide_mode_settings set its height:

keyword	default	effect
`pdf_aspect`	`"a4"`	width/height of a printed slide
`pdf_stretch`	`0.8`	multiplies the slide height only

pdf_aspect accepts:

a paper name: "a4", "letter" (landscape);
"screen": the browser window's ratio, so the page looks like the live slide;
a number 16/9, a string "16:9" or a tuple (297, 210).

A "screen"-shaped slide on a relatively taller sheet (16:9 on A4) leaves a blank band at the bottom. pdf_stretch takes part of that band back. The two combine: a printed slide's ratio is pdf_aspect / pdf_stretch, so the defaults ("a4" over 0.8) come out at about 16:9. Matching the paper's own ratio fills the sheet; a slide taller than the sheet is cropped by the paper, not scaled down.

Never shorter than the live slide

A slide is laid out at the window's width, so it is as tall as it is on screen and a shorter page would cut its bottom off: these keywords can only make it taller. Export from the window – and the F11 state – you will present with.

slide_mode_settings(pdf_aspect="a4", pdf_stretch=1)        # the A4 landscape shape itselfslide_mode_settings(pdf_aspect="screen", pdf_stretch=1.1)  # as on screen, 10% tallerslide_mode_settings(pdf_aspect=16/9)

font_size also applies to the PDF, so a smaller font puts more on each page.

Known limitations

Each slide prints fully revealed: pause steps are not split into pages.
webpage embeds restart when the pages are built, so the export waits a few seconds for them ("Preparing PDF…"); one that refuses to be framed, or that draws itself late, prints blank. Firefox's print preview can show an embed empty even when the saved PDF has it – trust the file, not the preview.
This is not pixel perfect e.g. there is a blank space at the right. Moreover, Julia types like x::Float64 are rendered differently in the browser and in the PDF.