# What kind of font is used in math mode of LaTeX?

For some reasons of compatibility and interactivity I need to create my own simple system for drawing the formulas. (So I need standard math sybols and something like \mathcal{N}.)

• Is there a way to use the LaTeX font?
• Are they "truetype"?
• Are they free for (non)commercial use?

I think that Unicode contains all of those symbols, but I need to draw them using some kind of pictures of symbols. I will use it with SDL2 and OpenGL.

I think the font LaTeX uses depends on the documentclass and other settings, but by default, it should be using the Computer Modern family of fonts. These can be downloaded from http://www.ctan.org/tex-archive/fonts/amsfonts/. I think cmsy-name like fonts contain math symbols, cmbsy-name like fonts contain bold math symbols, cmex-name like fonts even more symbols, etc. Just download the fonts and look at them in the font editor. I am no expert for fonts, but I think they are not unicode and all just support a limited set of characters. They are under the SIL Open Fonts Licencse, which should make them free for non-commercial usage (but better check this by yourself and don't quote me on that ^_^). They are not truetype, but pfb, which can be loaded in Java, for instance, but seemingly cannot be opened natively under Windows.

However, unless you need your text to look exactly like LaTeX' output and/or you need to distribute the fonts with your package, I would rather recommend using unicode fonts like, e.g., Arial Unicode. Using tools like charmap, you can find the right unicode code point for the maths symbol you like and then use that symbol. This way, you can always replace the font with another unicode font supporting the symbols.

Just to slightly correct Thomas Weise's answer - if you compile a straightforward LaTeX document without loading any extra packages, then the fonts used will be Computer Modern (not AMS fonts). The Computer Modern fonts are not TrueType fonts, and they're distributed through the "Knuth license". TrueType versions exist as part of Bakoma, but they have a non-free license.

MWE:

\documentclass{article}
\begin{document}
$$\mathcal{N}$$
\end{document}


Output of pdffonts:

name                                 type              emb sub uni object ID
------------------------------------ ----------------- --- --- --- ---------
HMBLMD+CMSY10                        Type 1            yes yes no       4  0
SDXKYB+CMR10                         Type 1            yes yes no       5  0

• Hm, I am not entirely clear about the relationship of the AMS font set and Computer Modern: I thought that they are basically the same, except that AMS adds some symbols and sizes. E.g., the AMS set contains the cmr fonts = Computer Modern Roman and also cmsy from your example and that alike? Is the difference just that or are there are other/visual differences? – Thomas Weise Jul 15 '15 at 21:48
• @ThomasWeise I think the answer lies somewhere in between. What I noticed was that the AMS font package doesn't include the font metric files for CM (*.tfm files). But now I see that the AMS package maps the CM font metric files to Type1 fonts that it provides (see .../cm.map), and my log file is telling me that this mapping is used: /usr/local/texlive/2015/texmf-dist/fonts/type1/public/amsfonts/cm/cmr10.pfb. I don't know what's causing this. pdftex.map has the line cmr10 CMR10 <cmr10.pfb, but it's not clear to me what makes it pick out cmr10.pfb in the amsfonts folder. – Sverre Jul 15 '15 at 22:36