Important information about the MathML fonts in Gecko 31

(apologies for possible multiple copies ; feel free to forward this message)

Dear all,

Starting with Gecko 31 (to be released the week of July 22), the 
recommended fonts for the MathML rendering are mathematical fonts with 
an OpenType MATH table [1]. The old math fonts (e.g. MathJax TeX, STIX 
General) are now deprecated in favor of the modern OpenType math fonts 
(e.g. Latin Modern Math, XITS Math, Cambria Math). There are still some 
known bugs/limitations in Gecko, math fonts and systems so that might 
take some time before the migration can be fully done. However, note 
that we plan to remove support for the old fonts in a near future, so 
please upgrade your setup as soon as possible and report any issues you 
find. In particular:

* For Web users: If you installed MathML fonts in the past, please 
consider cleaning up your previous installation. Read [2] for the latest 
documentation of the recommended math fonts. On desktop, if you use 
Windows >= 7 or if you have a TeX distribution installed, it's now 
really likely that you don't need to install additional math fonts. On 
mobile devices, the MathML fonts add-on [3] is still the only option for 
now but we have work-in-progress patches for Android and FirefoxOS. 
Currently, there is not any native feature to configure your preferred 
math fonts, but Firefox users can try the MathML-font-settings add-on [4].

* For Web authors: If you use Web font versions of deprecated math fonts 
(e.g. MathJax TeX or STIX General), perhaps with the help of the 
::-moz-math-stretchy pseudo-element, you should update your pages. The 
rule is now very simple: just apply the desired font-family on the 
<math> elements. You might also provide WOFF fallback or additional 
font-family for the text. Download [5] to get WOFF fonts together with 
CSS stylesheets to use on your Website.

* For software maintainers: Please ensure that an OpenType MATH font is 
available on your system or that the appropriate dependencies for 
Gecko-based programs are set. You might also want to remove obsolete 
fonts or at least drop the dependencies for Gecko-based programs.

* For font designers: You are invited to create your own math fonts and 
test them with Gecko. Note that fontforge has menus and a Python 
interface to do that [6] [7]. Existing math fonts have issues with 
ascent/descent, please be sure that the OS/2 metrics are consistent, so 
that they work the same in all platforms/browsers.

Related news:

* The STIX fonts (STIX-Word set) have an OpenType MATH table, but there 
are known to have many bugs. The STIX Consortium announced version 2.0.0 
for early 2015 but for now, it is recommended to use the XITS fork 
instead [8].

* Partial support for the OpenType MATH table is also available in 
WebKit Nightly and will improve the rendering of MathML operators [9]. 
Requests to make OpenType MATH font installed by default on iOS & Mac 
systems have been submitted to Apple.

[1] Section 6.3.6, 
http://mpeg.chiariglione.org/standards/mpeg-4/open-font-format/text-isoiec-cd-14496-22-3rd-edition
[2] https://developer.mozilla.org/en-US/docs/Mozilla/MathML_Project/Fonts
[3] https://addons.mozilla.org/firefox/addon/mathml-fonts/
[4] https://addons.mozilla.org/en-US/firefox/addon/mathml-font-settings/
[5] https://github.com/fred-wang/MathFonts/archive/gh-pages.zip
[6] http://www.fontforge.org/math.html
[7] http://www.fontforge.org/python.html
[8] http://www.stixfonts.org/
[9] https://bug-133569-attachments.webkit.org/attachment.cgi?id=233418

-- 
Frédéric Wang
maths-informatique-jeux.com/blog/frederic

Received on Sunday, 20 July 2014 13:59:09 UTC