Version 3 of the Open Font Format was officially published as ISO standard early this month. One of the interesting new feature is that Microsoft's MATH table has been integrated into this official specification. Hopefully, this will encourage type designers to create more math fonts and OS vendors to integrate them into their systems. But are browser vendors ready to use Open Font Format for native MathML rendering? Here is a table of important Open Font Format features for math rendering and (to my knowledge) the current status in Apple, Google, Microsoft and Mozilla products.
|Pre-installed math fonts||Make mathematical rendering possible with the default system fonts.||OSX: Obsolete STIX|
Chrome OS: no
|Windows: Cambria Math|
Windows phone: no?
|Firefox OS: no|
|MATH table allowed in Web fonts||Workaround the lack of pre-installed math fonts or let authors provide custom math style.||WebKit: yes (no font sanitizer?)||Blink: yes (OTS)||Trident: yes (no font sanitizer?)||Gecko: yes (OTS)|
|USE_TYPO_METRICS OS/2 fsSelection flag taken into account||Math fonts contain tall glyphs (e.g. integrals in display style) and so using the "typo" metrics avoids excessive line spacing for the math text.||WebKit: no||Blink: yes||Trident: yes||Gecko: yes (gfx/)|
|Open Font Format Features||Good mathematical rendering requires some glyph substitutions (e.g. ||WebKit: yes||Blink: yes||Trident: yes||Gecko: yes|
|Ability to parse the MATH table||Good mathematical rendering requires many font data.||WebKit: yes (WebCore/platform/graphics/)||Blink: no||Trident: yes (LineServices)||Gecko (gfx/)|
|Using the MATH table for native MathML rendering||The MathML specification does not provide detailed rules for mathematical rendering.||WebKit: for operator stretching (WebCore/rendering/mathml/)||Blink: no||Trident: no||Gecko: yes (layout/mathml/)|
update: Daniel Cater provided a list of pre-installed fonts on Chrome OS stable, confirming that no fonts with a MATH table are available.