It appears to be several popular programming fonts with a bunch of extra glyphs added. Does Vim require special font support, because I'm having a hard time figuring out the point of this.
Is this for people who like to put icons into code comments?
Powerline/Airline is one big one -- the status line in Vim is just a character-mode thing, but with a few extra glyphs (for line number, git branch, and arrows/wedges, most notably) it looks a lot better than if it's using a more limited character set.
vim-devicons is the other big one that this is supporting, which gives you filetype icons.
Are these things huge big deals? No. Are they nice things that make Vim's UI look a little cleaner and more informative within the confines of a pure character-mode application? Yes.
No, there's plenty of reasons why you'd want more characters available. I use emoji for git diffs in my vim line number column, for showing battery status, audio levels, etc in tmux, and so on.
Not really, that's the terminal emulator's job. If you want to use unicode fuckery for pointless hipster icons, you just need to have the glyphs in any installed font, and the terminal should substitute it when needed, no matter what your configured default font is (unless said font also provides the glyphs).
I get it, you don't like the pointless icons. Some do. Often when having a homogeneous naming structure with long filenames in NerdTree, it's nice to be able to say, "Oh this is the CSS file" without having to hit a capital A to expand the "drawer" to see what type of file it is. For the record... I don't own skinny jeans, and I'm probably far too old to be a hipster.
A reminder to those writing open source READMEs: People coming to your project have probably never heard of it before. Tell us what this is and why, don't bury the lede.
I confess I do run vim-airline and tmuxline so I am not entirely innocent when it comes to adding custom fonts to machines for my terminal. It makes them look a little bit nicer, doesn't cost much effort or screen space and doesn't degrade too badly.
For my eyes, vim-devicons looks like a crazy amount of icons for any console app. Can't say I am a fan but as always it is great to see diversity and tool makers making tools for every need.
I think we all look at this and think that it has crossed some line. But I also have to admit that I find myself lusting for one glyph or another, so I can't say where to draw it.
What advantage does this solution have over having a custom font configuration on Linux with fallback support for a font with unique unicode glyph support? In my case, I have Google's Noto font as my main font and have Font Awesome and Emoji One as my fallback fonts and it seems to cover everything.
I totally agree that fallback is the way to go. Unfortunately I couldn't get powerline glyphs to work on my archlinux box, lost patience and just grabbed the droid patched fonts.
I would say that it adds portability, consistency and makes it easier to have glyphs working straight.
I'm genuinely curious, do you have any idea how other OSs handle fonts? Does OSX have something similar to Linux's X11's font configuration? What about Windows?
Is this for people who like to put icons into code comments?