Hi all!
This is a bit of a technical question:
I use the function hb_ot_layout_get_size_params() to get the design size
of an OpenType font. The result specifies a design size in 1/10 of a point.
So, a design size of 100 means 10pt. OpenType/Harfbuzz assumes that 72
pt = 1 inch.
TeX on the other hand assumes that 72.27 pt = 1 inch. So, to convert a
design
size of 100 found for an OpenType font to TeX's points, I should
divide by 10 and then by 72 (giving the design size in inch)
and then multiply by 72.27 to get TeX points.
When I use this formula in HiTeX, my fonts are slightly larger than in XeTeX
and so are inter-word-spaces and inter-line-skips.
If I do not use the extra divide and multiply, my fonts are still not the
same size as those produced by XeTeX.
So how does XeTeX compute the design size of an OpenType font?
Regards
Martin
--
Martin Ruckert
Hochschule München
Fakultät für Informatik und Mathematik
