I am trying to minimize the vertical distance between controls on a programmatically constructed Windows Form (using C#). This involves setting the Height property appropriately.
I have found that if the text of the control does not contain any letters with descenders in them (i.e. does not have any of the characters j, g, p, q or y) then the control Height can be smaller than when it does contain such letters (if it does contain letters with descenders then the descenders are chopped off if the Height isn’t enough).
It will work fine to test for any of the above 5 characters as long as the language is English, or English – like, but I need to be able to cater for (just about) any language.
Is there a way, given some arbitrary Unicode character (and perhaps a font) to determine if that Unicode character has a descender or not?
There is no property defined for Unicode characters to indicate the presence of a descender, and it’s really a feature of glyph design rather than characters. For example, “Q” has a descenders in many fonts, and “J” has one in some. Besides, given the context, you should also consider diacritic marks placed below a letter, not just descenders of base letters. And probably diacritics above letters, too.
So you would need to read the font information (when available) about character dimensions, or tentatively draw characters in your software and measure their dimensions.
As a rule of thumb, any line height below 1.1 times the font size will cause problems with some characters and fonts. Using 1 (“setting solid”) is not enough, because characters may in fact extend outside the font size.