What is the relationship between a font Glyph Ascender and Descender in iOS?
问题 I'm working with fonts in a UILabel (iOS7) and have come across something I'm hoping someone can explain: What is the relationship between a fonts' Glyph, Ascender, and Descender? From the documents I've read the Ascender is the portion of a font above the baseline, the Descender is the portion below (returned as negative). The combined absolute values should be the max Height of the font. For example an Ascender of 255 and a Descender of -64 would give a total height of 319. However the