I’m trying to get up to speed with design principles and best practices for setting vertical dimensions in fonts. There are often discrepancies between what I read in OpenType documentation and guides, and what I see in practice that I’d like to understand -I assume it is the experience of the type designer that is seen here.
In Abyssinica SIL, the height points of the Latin letters are consistently at 1374 points, however, the Caps Height is set to 1108 -shouldn’t these be exactly the same? Why would they be different?
I see this difference in many fonts which has me wondering how seriously to take the Caps Height and x height dimensions. In a multi-script font, does the Caps Height and x height impact the non-Latin letters in any way when the fonts are used by applications?
What approach is taken to set the height of the non-Latin letters relative to the Latin letters? “H” is often used as a reference letter, is a reference letter selected from the non-Latin script and then sized against “H”? Or against the Caps Height?
This is my untrained instinct, I’m often surprised though to find fonts with Latin letters paired with non-Latin letters with surprisingly different heights relative to one another, so there seems to be another design principle at play here.