[OLPC library] questions about PDFs

Fri Sep 26 18:18:12 EDT 2008

A few notes on books:

please check out the latest wikibooks bundle in
[[Collections/G1G1/8.2]] -- unfortunately, those are still pdf's.
This should change for the next release, hopefully in time for 8.2.1.

Josh Gay has just updated the textbookrevolution.org site -- take a look!

HTML books : better tools are needed for neatly-formatted html export
from various raw formats.  Mediawiki, pdf, doc, and plaintext are four
of them.

epub and similar books : We also need a bookreader that can parse
modern epub formats.  "Read", having claimed the default verb, needs
to address this -- even if that means no longer simply being evince in
a candy coating.

Sayamindu is picking up maintainership of read, and as 8.2 heads out
the door I'm sure he'd appreciate these and other ideas and
suggestions :-)

SJ

On Fri, Sep 26, 2008 at 6:07 PM, S Page <info at skierpage.com> wrote:
> Ahh, several topics dear to my heart.
> * Browsing to PDFs is problematic for the reasons you identify and more.
> * But anyway, prefer HTML with advanced CSS over PDF for documents.
> * And prefer SVG over PDF for figures.
>
> Diane Serley wrote:
>
>> But when I
>> attempt to read one, the PDF is "downloaded" from the library directory
>> into the Journal. I had expected that Read would launch and read it
>> directly, or that it would appear in Browse. But the download means that
>> I have 2 copies of the file in my XO: one in the Library and one where
>> ever the Journal is storing stuff...
>
> That's right.  And every time you navigate to the PDF in Browse and do
> the download-Journal-launch dance, another copy of the PDF is added to
> the Journal's datastore!  I wrote up the issues in
> <http://wiki.laptop.org/go/Talk:Read#Many_issues_going_from_Browse_to_PDFs>
> , e-mailed "downloaded files and the Journal" to devel at laptop.org
> <"http://lists.laptop.org/pipermail/devel/2008-June/015379.html>, see
> bugs 8155 and 8330.
>
> On any personal computer the general principle of saving stuff from the
> browser is "first check if you've downloaded it already".  On the XO
> that even applies to local files for Read that OLPC Library presents: to
> re-read a PDF document, kids should restart it from the Journal, instead
> of returning to pages in Browse and clicking again.
> (I haven't checked, does the Sugar documentation mention this)?
>
> Thus the nifty friendly "OLPC Library" start page in Browse encourages a
> sub-optimal interaction with PDF documents.
>
> Your idea that Browse should launch Read is what I expected too  I'm
> pretty sure Browse could pass a URL like http://gutenberg.org/some.pdf
> or file:///home/olpc/Library/another.pdf directly to the Read activity
> and eliminate the save to datastore and launch from Journal out of the
> way.  But when this came up on devel at laptop.org people raised issues
> with the XO's security model; see bug 6958.
>
>
> The best way to avoid these problems is to not use PDF.  Even if they
> were solved, PDF has lots of downsides as a format for the XO.  I filed
> bug 7898 to suggest the Sugar activity handbook from Ship.2 not be a
> PDF, repeating some of the downsides in
> <http://wiki.laptop.org/go/Talk:Read#Document_limitations.3F.3F> (the
> bug was obsoleted when all built-in bundle-archives were removed).  The
> killer problem with PDF is it doesn't re-layout when you rotate the
> screen, so you can't get appropriate margins for both orientations.
>
>> I made a collection (.xol) of PDFs and it installed fine.
>
> Can you go back and create nice HTML pages from the source material?
> The publisher and others should be willing to help.
>
> PDF's pluses include that you can use better typography and control the
> fonts.  But the Mozilla engine under Browse supports advanced CSS (see
> <http://developer.mozilla.org/en/CSS_improvements_in_Firefox_3>) that
> allow book-like typography, see e.g. <http://webtypography.net/toc/>.
> And if content required a particular font I think OLPC would be amenable
> to installing it, or maybe the library content bundle could.  Also, CSS
> fonts are coming to the next iteration of the Mozilla engine, so HTML
> pages can use custom fonts.
>
> Besides books, people use PDF for diagrams and figures.  But those are
> better done as SVG files that Browse can directly render.  I filed bug
> 7652 that the World Factbook maps that were in the Ship.1 bundled
> library should be re-done as SVG.  Since SVGs can animate and respond to
> JavaScript, someone could do an incredible Browse-based Atlas that lets
> you show and hide features like rivers, towns and borders, and even
> implement quizzes (hide text labels and respond to clicks).  Awesomeness!
>
>> Am I doing something wrong, or is this the expected behaviour?
>>
>> Because Browse isn't reading it natively, I'm assuming that Browse is
>> not set up to deal with the PDF mimetype. Is there a file I can edit to
>> get it to recognize the mimetype?
>
> No browser can render PDFs natively.  But you can use a plug-in to
> render PDFs in a browser, just like Browse-with-Totem can play the OGG
> video and audio mime types.  There is a browser plug-in for Evince, so
> the Read activity could be subsumed into the browser.  This was filed as
> bug 3212 and possibly another bug, closed invalid.  I disagree with
> closing it; the submitter plaintively asks
> "why should the child have to care that PDF books will be in Read and
> HTML books will be in Web"
>
> If someone has Firefox and Evince expertise and wants to experiment on a
> Linux box or an XO, they could see how well Evince works as a plug-in,
> try passing URLs from the command line to Evince, set up external read:
> handlers in Firefox, etc.
>
> But in my opinion, PDF is rarely if ever the best format for presenting
> content on the XO.
>
> Cheers,
> --
> =S Page   user:skierpage
> _______________________________________________
> Library mailing list
> Library at lists.laptop.org
> http://lists.laptop.org/listinfo/library
>