[mpeg-OTspec] Re: MarkToBase clarification?

[Martin Hosken]

Dear Ken,

To repeat for everyone:

> > > "To combine the mark and base glyph, the client aligns their attachment points, positioning the mark with respect to the final pen point (advance) position of the base glyph."

To clarify this statement (and I would have others check this). What this is saying is that marks are attached to their bases based on attachment point alignment, as others have said, but the origin of the mark is stored as an offset relative to the advance of the base. So if, after you have attached, you change the advance of the base, all the attached marks will move too. So, if you are going to change the advance of a base, do it before you attach the marks. Attach late is the general advice in OT.

Yours,
Martin