I have just released version 0.4 of CapyPDF. You can get it either via Github or PyPI. The target of this release was to be able to create a pure Python script that can be used to generate PDF slides to be used in presentations. It does not read any input, just always produces the same hardcoded output, but since the point of this was to create a working backend, that does not really matter.
- The source code for the script is here. It is roughly 200 lines long.
- The PDF it creates can be accessed here.
- A screenshot showing all pages looks like the following.
What the screenshot does not tell, however, is that the file uses PDF transition effects. They are used both for between-page transitions as well as within-page transitions, specifically for the bullet points on page 2. This is, as far as I can tell, the first time within-page navigation functionality has been implemented in an open source package, possibly even the first time ever outside of Adobe (dunno if MS Office exports transitions, I don't have it so can't test it). As you can probably tell this took a fair bit of black box debugging because all PDF tools and validators simply ignore transition dictionaries. For example transcoding PDFs with Ghostscript scrubs all transitions from the output.
The only way to see the transitions correctly is to open the PDF in Acrobat Reader and then enable presenter mode. PDF viewer developers who want to add support for presentation effects might want to use that as an example document. I don't guarantee that it's correct, though, only that it makes Acrobat Reader display transition effects.
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