Confused with diaeresis and acute in Latin vs Greek

Joon Park

As far as I can see, some fonts do not make distinction between them minus Greek calls acute, tonos instead. Do you guys keep them same in your glyphs?

Additional questions related to the subject:

Apparently U+1FEE is a duplicate as they confused oxia and tonos as different marks when they are same. Do I need them both? or Just ignore the duplicate?

Should I not include grave (varia/bareia) version of accent marks since they don't used those since simplification?

Chris Lozos

I always make a different glyph for tonos and adjust the angle more upright. Also, you need to decide if you are doing a full polytonic or just monotonic.

Jackson Showalter-Cavanaugh

tonos ≠ acute 

Joon Park

Chris Lozos said:

I always make a different glyph for tonos and adjust the angle more upright. Also, you need to decide if you are doing a full polytonic or just monotonic.

"monotonic orthography was imposed by law" but since there are people still using  polytonic system so I would like to go for polytonic.

How do you deal with combining/spacing accents? (1F00-1FFF has duplicates but also has diaeresis varia, although no combining glyph.) 

Chris Lozos

in for a penny in for a pound

Joon Park

Chris, based on my research tonos is indeed acute but during transition to monotonic system and orthographical reforms, they were using the upright version which gave false impression of being entirely new accent. Thus we end up having extended table with duplicates (oxia vs tonos).

So basically we're using different shape glyph for tonos because that's simply what people have been familiar for long time? Please correct me if I'm misinformed.

More I research more I realize the mess unicode is

Thomas Phinney

Joon Park said:

So basically we're using different shape glyph for tonos because that's simply what people have been familiar for long time?

Aside from legibility and spacing concerns, “we're using XXX shape glyph for YYY because that's simply what people have been familiar for long time” can be used to describe pretty much all of type design. Shapes are driven by conventions.

In the case of the tonos, when set with a cap it precedes the cap instead of going above; using a conventional “acute” shape instead of a steeper one exacerbates the spacing problem inherent in this situation, no?

Chris Lozos

the tonos, when set with a cap it precedes the cap instead of going above

There is also a separate cap tonos so this might be confusing

John Hudson

tonos ≠ acute 

Well, it does and it doesn't, 'cause tonos = oxia, and oxia/tonos have canonical decompositions in Unicode to acute (both spacing and combining). So in this particular and unavoidable sense, tonos = acute, which means that OT language-specific acute glyphs (and grave for polytonic varia) need to be provided for the 'grek' script tag. [Localised versions of quote-like combining marks are also needed, since these have compatibility mappings from koronis, psili and dasia).

Graphically, the oxia/tonos is usually larger and steeper than the Latin acute, and like the Greek accents in general should be more prominent than Latin diacritics.

John Hudson

In the case of the tonos, when set with a cap it precedes the cap instead of going above

Most people are so used to seeing that convention, they don't realise just how recent it is. The earliest systematic use of prescript breathing and accents on caps I've found is 19th Century. Before that, marks appear either above or after caps. The suppression of marks in all-caps settings seems to date from the same period.