Re: The current state of rendering and overlap

Alexei Podtelezhnikov <[email protected]> Tue, 19 Dec 2023 14:26:03 -0500
Newsgroups gmane.comp.fonts.freetype.devel
Message-ID <[email protected]>
> 
> CFF2 is released, has been for years. As far as I know there's no solid convention for ignoring unrecognized operators in a CharString, so this would be CFF2 minor 1 at best. Which would be years out in terms of support.

We can do it in days for FreeType, then it is a matter of upgrading downstream.. Behdad floats cubic outlines in TrueType, which is a much larger undertaking but not impossible.

> 
> Practically speaking I don't think this could wind up being a "this glyph has overlap" flag, as in CFF2 overlap is valid anywhere. If something were added it would be more like a "this glyph doesn't have overlap, you can optimize the rendering" flag.

The 4-fold speed difference is not an optimization it is a liability which should be taken explicitly. Some overlaps at single points are not that noticeable. Only long runs along the axes are bad. So I disagree with default oversampling even for variation fonts.

> 
> Behdad - there's no provision for a relevant flag in VARC currently, correct? (I'm not sure there was one in the glyf-based system, as I don't remember a place where the flag would have lived.)