I'm wondering if anyone here has designed a font in which accented glyphs are decomposed into base glyphs and combining marks in the ccmp feature.
e.g.
sub aacute' by a acutecomb;
I'm thinking here of, e.g., a script face in which each base glyph has numerous different contextual forms where it might be simpler to ignore most marks when constructing one's contextual rules.
Will most software be able to deal with this, or would this approach create problems in some applications?
Comments
Your script face example is closer to what we do in complex Arabic fonts in which we decompose archegraphemic letter shapes and their differentiating dots so that letter shape contextual substitutions can be handled on a small subset of glyphs.
3. I imagine Khaled is saying “no” to the pitfalls, rather than to the flexibility.
The main pitfall is one that applies to kerning with variable fonts in general, and not to your decomposed approach in particular. The problem is that interpolation is linear, and sometimes the interactions of two shapes would benefit from doing something quite unlike linear interpolation, for the kerning values.
For example, consider the “To” combination in a sans serif, one in which at the heaviest weights the “o” becomes unable to tuck under the T, and this transition occurs (as one would expect) rather abruptly.
If you kern the bold and the light “To” correctly, the bold with its minimal kerning will have undue influence on in-between situations, which do not have the problematic shape interaction. So they end up under-kerned.
There is no easy solution for this, that I know of.
I do hope I haven’t derailed the discussion too much already, @André G. Isaak, but the issue of kerning in variable fonts sounds like a deficiency of the spec. One that maybe non-linear interpolation could help solve, if I understand correctly?
I would be curious to hear just how much space you save by using your approach, in absolute and percentage terms.
I would be curious to hear just how much space you save by using your approach, in absolute and percentage terms.