[2 mod] Style: v ν x χ Greek and Latin characters use the same glyph in italic style

Given that Ubuntu has its roots in technical work, and precision is one
of our core values, I do think we need to differentiate these glyphs in
order to be useful in technical documents that use greek symbols in
equations that might also use latin symbols to mean quite different things.

I think this was missed in the initial design review and needs to be
addressed pre-1.0. There may already be a dup of this, but I want to
record our firm intention to address it.

Mark

In the circumstances of scientific work I can see the problem with some of the characters in Greek and we will address this in the next review. Thanks for being this specific pointing this out as in a more day-to-day environment this would not really have been an issue.

Bruno

The problem with artificially differentiating the execution of Greek,
Hebrew, etc. characters for the purposes of maths setting is that it
makes the setting of everyday text in those scripts look quite
preposterous - flowery for the sake of being flowery, and a result that
isn't cohesive with the rest of the font.

The way Unicode has approached it is to have a range purely for letters
for maths setting - where distinction in weight, style, script, and
appearance can be absolutely assured. The range is at U+1D400-U+1D7FF.

Dave

Thank you Dave!
I had absolutely no idea, that Unicode has a special Block for this purpose. Am I right, that this block is not yet supported by the Ubuntu Font Family?

I really love the new font. But nevertheless I am quite sure I will use it exclusively on the screen. I still prefer serif fonts for my printed documents. I am sure this question is already answered, but will there be a serif version? There, I think, the differences in the glyphs are much more easy to obtain by slight changes.

The maths alphanumerics block isn't on the current roadmap. I spoke to
Bruno earlier and he suggested we add just those two variant characters
to the block to help with maths setting, but obviously there are issues
with having a sparse block, and even bigger issues with the block being
beyond the Unicode BMP.

Dave

Possibly less-invasive approaches:

  1. Have chi reach the descender again (it did in earlier versions; this was a vertially scaled 'x' glyph)
  2. Ensure that there *is* variation in between v and ν in the italics at least.

I would say that adjusting the chi is a good idea, and that we should
explore the options for nu. In our own library InterFace makes a
reasonable distinction between nu and v without getting overly flowery,
but I can't say for sure whether the same approach would suit Ubuntu's
design. Most sans fonts don't seem to bother making a distinction as the
options are limited where there are no serifs.

Dave

There's a glyph a for the current Cyrillic izhitsa ('ѵ') which shows one option (although historically I believe that this is a deriviative of upsilon rather than nu). See attached PDF for quick ideas.

This bug also affects phoneticists, seing as the International Phonetic Alphabet – the universal means of notating language sounds – distinguishes clealy between [x], a velar fricative, and [χ], a uvular fricative. These are two different sounds that may distinguish one word from another, and therefore the distinction is a very important one.

Compare https://en.wikipedia.org/wiki/Voiceless_uvular_fricative and https://en.wikipedia.org/wiki/Voiceless_velar_fricative. It's absolutely necessary to fix this, or the Ubuntu font face cannot be used for describing the phonetics of languages that use a uvular stop, which quite a few do – see the first link.

In a pre-release 0.84 test version, the chi character is very different from the x (bug 647092), and the nu character is *slightly* different from the v.