[HarfBuzz] Library similar to HarfBuzz to shape mathematical equations?

[Khaled Hosny]

On Wed, Dec 12, 2012 at 11:40:40AM -0500, Behdad Esfahbod wrote:
> On 12-11-14 05:32 PM, Khaled Hosny wrote:
> > we
> > also use some private API to read MATH table on our own, so if HarfBuzz
> > provided an API to read MATH table that would help greatly.
> 
> What kind of API do you currently have?  Just want to get a feel of what's needed.

Rather than what we have, I was thinking of something along the
following lines:

  hb_math_get_constant (font, constant)

  hb_math_get_glyph_italic_correction (font, gid)
  hb_math_get_glyph_top_accent_attachment (font, gid)
  hb_math_get_glyph_kern (font, gid, side, height)

  hb_math_get_glyph_horizontal_variant (font, gid, width, good_fit)
  hb_math_get_glyph_vertical_variant (font, gid, height, good_fit)

 ‘good_fit’ is set to false if the returned glyph is the largest variant
  available but smaller than the requested size, so that the user calls
  the next functions.

  hb_math_get_glyph_horizontal_assembly (font, width, size)
  hb_math_get_glyph_vertical_assembly (font, height, size)
  
  Returns a positioned array of glyphs that fits in the requested size.
  May be it can combined with the above functions returning an array of
  length one for the case a single good fit variant was found.

Those are the parts of the MATH table we currently use, there is also
Murray Sargent blog post which describes the API they have:
http://blogs.msdn.com/b/murrays/archive/2010/01/12/special-capabilities-of-a-math-font.aspx

Regards,
Khaled