The accents, aka, the combining diacritical marks, are combined with the base glyphs to form accented characters.
For example, to type résumé with the correct French spelling, one should use é acute. On an International keyboard, the accent is typed first, followed by the base glyph, and the result is an accented glyph. Accents are usually “dead” keys, i.e. nothing seems to happen at first, but when a vowel is typed, the accented vowel appears àèìòù or áéíóú.
The tilde accent is similar ãẽĩõũ and also ñ as used in Spanish. The asciitilde ~ is not an accent, but a regular glyph, which is a symbol for “about.” In a font, it has a different design and different spacing. Since it is used as a Maths symbol, it is a good idea, IMO, to design it on the figure width, aligned vertically with other symbols like += and ÷ thus ~
Combining diacritical marks (accents) have zero advance width, and a negative left side-bearing. They are usually designed to be positioned above lowercase glyphs, without any vertical adjustment, so they are above the x-height. They are shifted up by the font for capital accented letters: Á É Í Ó Ú.
A common practice is to align accents vertically about their centres, but the font designer may prefer to use bottom alignment. That will depend on the font’s design. Some fonts may have smaller accents for use above capital letters, where vertical space is limited.
- Low Profile Diacritics.png (12 KiB) Viewed 5780 times
Examine any of
my free fonts to see how they are designed, or any standard Windows fonts.