Re: [evince] Ink Annotations Toy Implementation

[Daniel Sim <Daniel Sim 2010 pem cam ac uk>]

> I don't think you need extensions to PDF, but of course I don't know your
> goals. I would imagine that
> using the /AP section of an ink annotation you can do whatever you want, but

> From a quick reading of the PDF spec 1.7 it seems the /AP section just
contains the same entries as in a regular Ink Annot. Not quite what I
wanted -- I wanted to add a *new* entry called InkWidths, an array of
array of reals, whose lengths matches that of InkList, that specifies
how thick the ink is at each segment.

In Xournal, you get very nice inks using this feature and a
pressure-sensitive tablet! But yea, it would't make sense to do this
as a start.

Do you know, by any chance, how PDF readers are supposed to handle
unknown Dict entries?

> I haven't try it though. In any case, iI think it would be
> best to first implement things that conform to the PDF spec. If you still
> want to do extensions, I guess they can be saved as metadata together with
> the file (this of course may cause problems when copying the file.. or send
> it) or just doing a sort of PDF + json or whatever you like (but in two
> files could be simpler for evince)