Re: Imprecise font scaling
Werner LEMBERG <[email protected]>
| Newsgroups | gmane.comp.gnu.lilypond.bugs |
|---|---|
| Message-ID | <[email protected]> |
>> However, 2 * 3.86523438 = 7.73046876 != 7.73242188.
> I'm quite sure this is because of
>
> int pango_size = static_cast<int> (
> std::lround (static_cast<Real> (requested_size) * PANGO_SCALE));
>
>
> in lily/font-select.cc, which we cannot really do anything about,
> because the Pango API
>
> https://docs.gtk.org/Pango/method.FontDescription.set_size.html
>
> expects an integer size scaled by PANGO_SCALE, which is 1024. That
> is, we are limited to a precision of 1/1024 points on the font size.
Shall we document this somehow?
Werner