Where is that Summary from? It looks like some kind of test result, but without knowing what is being tested for, it is impossible to determine what might need to be done.
OpenType Layout tables may contain Language System trees for features and lookups, but they don't have to, and there is no required set of Language System entries that needs to be included in a font. Everything depends on the design of the font, how it works, and what language-specific behaviour it might require.
This Summary is from the testing page of Alphabet. You can see detailed results below, in the same page. Click in the entries with <100% to see the lacking characters:
Where is that Summary from? It looks like some kind of test result, but without knowing what is being tested for, it is impossible to determine what might need to be done.
OpenType Layout tables may contain Language System trees for features and lookups, but they don't have to, and there is no required set of Language System entries that needs to be included in a font. Everything depends on the design of the font, how it works, and what language-specific behaviour it might require.
It looks like a simple Unicode codepoint check against a series of "required" (etc.) for a series of languages. What is your concern? If you intend to fully support your example "Church Slavonic", just add the missing characters.
An excellent place to find such tests is Stefan Peev's LocalFont.eu. (By the way, the whole localfonts site is excellent.)
Thank you, Igor. Very nice of you. I just started a new section in LocalFonts - section JOURNAL. It will be another place to discuss the issues about the languages and the typography.
Comments
OpenType Layout tables may contain Language System trees for features and lookups, but they don't have to, and there is no required set of Language System entries that needs to be included in a font. Everything depends on the design of the font, how it works, and what language-specific behaviour it might require.
http://www.alphabet-type.com/tools/charset-checker/