Text font commands don't stack right

[edemaine]

\textbf{\textit{x}} should produce a bold-italic "x", but it currently produces a nonbold italic "x" because all KaTeX commands reset the entire font. My understanding is that this is correct for math font commands (\mathbf{\mathit{x}} correctly produces a nonbold italic "x"), but incorrect for text font commands. (How asymmetric...) By contrast, \text{\textbf{\it x}} (using \it implemented in #675) should produce a nonbold italic "x", because old font commands like \it should reset the font.

This would be a moot point if there weren't bold italic fonts available, but there are. This would also require creating Main-BoldItalic fonts; see below.

[k4b7]

Nice find.

[ronkok]

@kevinbarabash Many issues, like this one, are blocked by missing font glyphs. It would be helpful if we had a single list that identified all of the desired glyphs. Then, if someone took on the font task, they would have a ready-made TO DO list. I wouldn't mind putting together such a list.

Would you rather have it in an issue or a project?

[k4b7]

@ronkok a project would be a good way to track this kind of stuff. Updating fonts is currently blocked on creating a separate repo for fonts. I'll try to tackle this this weekend.

[ry-randall]

Was going to open an issue on this, but just came across this.

I'm attempting to do: \textsf{\textbf{Hello world}}, and while it renders in bold, it does not render in Sans Serif font.

Is there any update on this issue? What can I do to help?

[k4b7]

@rrandallcainc it looks like we have the fonts. I think Option#withFont needs to be updated to so that instead of simply replacing the .font property, we'd modify it. It might even make sense to turn .font into .fonts so that we can toggle the active fonts by adding/removing them from the list of fonts. We'll also need to apply one or more font classes from https://github.com/Khan/KaTeX/blob/master/static/katex.less.

[ry-randall]

@kevinbarabash Okay, I'll give this a shot. Thanks.

[ry-randall]

@kevinbarabash I noticed in: https://github.com/Khan/KaTeX/wiki/Function-Support-in-KaTeX that there's no support yet for a bold/itatlic Sans Serif font (along with others), but it looks like they are contained inside of the "fonts" folder. Do we know what's blocking these from being exposed?

[k4b7]

@rrandallcainc you'll need to create an entry in mapping.pl that looks something like:

$map{cmss10} = {
  "SansSerif-Regular" => [ ... ],
};

I don't know what the actual font names are. My guess would be cmsb10 and cmsi10.

[ry-randall]

@kevinbarabash @edemaine It looks like (if this were fixed) \textbf{\textit{x}} should be rendering a Main-BoldItalic font. However, I don't see that available either through Katex or MathJax-Dev. Am I missing something?

[k4b7]

@rrandallcainc if it's not in either place, but it can be added, but this will mean regenerating the fonts. Before we do that I'd like to merge in #891 so that we can the size of the KaTeX repo relatively small. If you have some time maybe you could look over that diff. (edited for grammar)