Re: [ft-devel] Stem darkening toggling API

[Nikolaus Waxweiler]

> > so I finally got around implementing a concept: a new API entry
> > point `FT_Face_SetStemDarkening( FT_Face face, FT_Bool enable )`.
>
> What is the intended scenario for this function?  What type of
> application is going to use it?

Every toolkit that wants to apply linear alpha blending and gamma 
correction when rendering fonts. I made it a separate function instead 
of a load flag because you said we're running out of flags :) And, I 
made it a FT_Face property because Behdad said that would make the API 
more thread-friendly.

> > It toggles a new member of FT_FaceRec `no_stem_darkening`.
>
> You can't modify `FT_FaceRec' since it would break ABI.  However, you
> can add stuff to `FT_Face_InternalRec'; this seems to be sufficient
> for your proposal.

Ah, okay.

> > To get rid of duplication, the `no_stem_darkening` property should
> > probably be removed from the drivers and the darkening_parameters
> > moved to FT_Face.
> >
> > So, comments?
>
> If we are going to move properties from `FT_Library' to `FT_Face', I
> would rather like to have a generic interface that manages options for
> `FT_Face': something like an `FT_Face_Option' function, probably using
> the `FT_Parameter' structure so that arbitrary data can be set (and
> retrieved).

Can probably do.