[luatex] Kerning: when does it not work?

[Heilmann, Till A.]

On 04/05/2011 11:11 AM, Paul Isambert wrote:

> [...]
> So, Till, you're most unfortunate. On the other hand, could the fine 
> typography you're trying to achieve (as exemplified by your attention to 
> kerns) tolerate such things as urls in the main text? Wouldn't they be 
> better placed in a footnote of their own, with linebreak done by hand? 
> Oh, yes, I'm drowning the fish, as we say in French :)

My oh my, what have I gotten myself into?! ;-)

In my real-life project, URLs (like the [numeral]/[numeral] combination) are mostly part of automatically generated bibliographic entries and so occur either

a) in citations inside footnotes (with Dominik's authortitle-dw style and typeset in TeX Gyre Heros) or

b) in the bibliography (typeset in TeX Gyre Bonum--don't ask about the peculiar mix of serif and sans-serif, these are my publisher's guidelines).

So there is not much I can do about line breaks manually in these cases, I guess.

Let me see, if I got this right: Kern values (not just the ones added in OTF feature files, for example, but all existing kerns for a given font) can be and will be suppressed by TeX and/or several of its packages in a number of different situations for a number of different reasons (penalties, glues, math mode ...) Therefore, sorting this out would require a lot of work from a lot of people in a lot of different places. Maybe collecting and documenting all the stumbling blocks obstructing correct kerning would be a first step towards an eventual long-term solution?

Admittedly, my problems with kerning are but one detail of typesetting and not being able to correct poor kerning in a few--but recurring--instances does not mean the end of the world. (There will always be cases you have to adjust manually anyway, like between letters/punctuation marks and footnote reference marks.) I am nevertheless somewhat surprised that I seem to be one of first/few people asking about this issue. As I said: It is a detail. But then again, typography is all about details.

As always: Thank you for all your help and advice.

Best regards,
--Till