[pdftex] Pop-ups in PDF files

[Piet van Oostrum]

Hello,

I need to make a PDF document with pdflatex, where the user can click at
certain points to have additional information pop up. In the actual case
the pop-up will contain source code that is connected to the click
location.

>From what I have read in the PDF reference manual I see three
possibilities:
1. Annotations. These have the disadvantage that they can only contain
   plain text. No layout whatsoever. They can appear in a separate
   `window'.
2. Optional Content groups (layers). AFAIK these can only appear inside the
   main window of the document. I wonder if you can pop up an OCG in such a
   way that it hides the page contents underneath it without explicitely
   disabling the contents underneath (if the contents is text). If not,
   then it isn't usable for my purpose. I have only seen examples like
   drawings, where the layers were used to supply more detail, and slides
   where pieces of text where switched on/off.
3. An embedded PDF file with file annotations or link annotations pointing
   to a page in the embedded file. This would give full formatting
   possibilities and separate windows if I want. I wonder if there are
   disadvantages of this approach. Alternatively I could use a separate
   embedded PDF file for each pop-up.

Please let me know what your experiences are, and if you have some examples
and/or code to share I would appreciate that.
-- 
Piet van Oostrum <piet at cs.uu.nl>
URL: http://www.cs.uu.nl/~piet [PGP 8DAE142BE17999C4]
Private email: piet at vanoostrum.org