[RFC] Additional font rendering strategies for bold/italic fonts
(bear with me to the end :D)
So far the policy for this has been to ensure that Monospace fonts work as they should and assume non-Monospace fonts will look bad. Unfortunately this is becoming harder.
Vim operates as a grid of letters where each letter should always have the same width - regardless of the style(regular/bold/italic). So the kind of fonts we load can be split into the following groups:
Non-Monospace: like Arial - there is not much we can do about this, we assume a "reasonable" width for the font and hope for the best.
Full Monospace fonts: like DejaVu Sans Mono - i.e. fonts that are Monospace and provide regula, /bold and italic types. Ideally this is what you have, all font types have the same width - currently these are the fonts that work well in vim-Qt.
Monospace fonts, that don't have bold/italic variants, like Inconsolata or Monaco(Linux). These fonts will look ok until you want to use bold or italic, then the system will find an "approximate" replacement, i.e. the font width wont match. Currently we treat these fonts as we treat non-Monospace fonts.
Now looking at some other text editors, it seems that when they can't find a suitable bold/italic type they either fake it(Textmate) or they don't use bold(MacVim?).
I'm not sure how to do this, or which strategies to adopt for vim-Qt. Other programs seem to have different strategies(iTerm), so any input is welcome :D