Software I like: STIX Fonts

‘The mission of the Scientific and Technical Information Exchange (STIX) font creation project is the preparation of a comprehensive set of fonts that serve the scientific and engineering community’.

STIX 2 was released 2016 Dec 1.



I have created a variant of the STIX fonts called Mastic, which stands for ‘Mastic is almost STIX’. It is available as, under the same licence as the STIX fonts (viz., SIL Open Font License, Version 1.1). It addresses a number of issues in the STIX fonts.

The creation of the Mastic fonts has been my first experience with FontForge and I don’t really know what I’m doing, especially when it comes to hints and kerning, so there may well be problems.

Lower-case italic v and w

Test of Mastic font

In some fields it is important to distinguish between lower-case italic v (e.g., velocity) and lower-case italic nu (e.g., Poisson’s ratio, ν). This distinction can be made by using a rounded v, which STIX has as MATHEMATICAL ITALIC SMALL V (U+1D463). However, the use of characters beyond the Unicode base plane is still a problem in many applications. Even if it were not a problem, it is desirable to use a rounded italic v (and w) in regular text in the same document, for consistency, and it would be very awkward to have to use the MATH v and w every time. Therefore, it would be nice if the regular italic v and w (U+0076 and U+0077) were rounded rather than angular as they are now in the STIX font. This is the situation in the Computer Modern font and also in some others, like Palatino, Georgia, GUST’s TeX Gyre Bonum (also the TeX Gyre Pagella and Schola), Proforma, New Caledonia, Dustismo Roman.

I have therefore modified the lower-case italic v and w in Mastic to be rounded.

Small caps

Test of Mastic small caps

The STIX 1.1 fonts did not include any small caps, so I implemented some. I did it by scaling the capital letters by 83% with integer rounding, which resulted in vertical-stem widths equal to those of the original lower-case letters.

Note that in OOo/LO Writer, these small caps must be invoked by specifying a different font (in this case MasticSC) and not by just specifying the small-capitals font effect, which will cause the font’s upper-case characters to be scaled to produce artificial small caps. Similarly, use of the CSS font-variant:small-caps style on the Web will result in artificial small caps like this.

‘True small capital variants (Latin, Cyrillic, and Greek), accessible via the OpenType font feature smcp, have been added’ in STIX 2.

Defective math operator

Test of Mastic font for U+2299

I have modified the CIRCLED DOT OPERATOR (U+2299) (⊙) in the regular font to correct its inconsistent size compared with its neighbours (as pointed out by wiedeking on 2011 Dec 30 in the STIX issue tracker).

This problem has been fixed in STIX 2.

R. Funnell
Last modified: 2016-12-01 22:23:39