Re: [help-texinfo] Umlaut strangeness

[Gavin Smith]

On 1 June 2016 at 16:04, Andreas Falkenhahn <address@hidden> wrote:
> Hmm, this is really weird. When using
>
>     @documentencoding ISO-8859-1
>     ....
>     @chapter 0xdc
>
> the character is rendered correctly on the PDF page but not in the bookmarks!
> If I leave out the
>
>     @documentencoding ISO-8859-1
>
> then the character is rendered correctly in the bookmarks but not on the
> page! This is pretty confusing.

> I'm not sure whether you're saying that what I want to achieve is actually
> impossible or whether it is possible.... from what you've said I'd infer that
> it should be possible to use umlauts in the bookmarks *and* on the pages
> if I just use ISO-8859-1 because the bookmarks use Latin 1. But it doesn't
> work, cf. see above.

The problem is the TeX fonts - they don't use ISO-8859-1. So if the
document encoding is declared to be ISO-8859-1, each character is
transformed into TeX commands to print that character, e.g. 0xdc into
@"U. That in turn becomes U when the PDF outline is generated.

This could in theory be changed, but there are complications, like any
differences between ISO-8859-1 and the PDFDocEncoding encoding. Only
ISO-8859-1 could be supported this way.

If it's possible to use UTF16-BE for the outlines, that would be a
good solution, as long as the document used UTF-8 as its encoding. In
that case I imagine the encoding could be converted automatically,
without the need for any large translation tables.

> So is it possible to use umlauts on pages *and* in the bookmarks or can I
> have umlauts only on one side - pages *or* bookmarks but not both?

It seems not at current.