Re: [ft-devel] implementing detection of hinting/rasterization errors in fonts

[Hin-Tak Leung]

Hi,

I had a look at the other errors showed by analysing win8.1 shipped fonts with 
the 2003 binary,
and updated "https://github.com/HinTak/Font-Validator/issues/5"; with some 
details. Anyway, the summary is this:

Out of the 7 kinds of errors/warnings that the 2003 binary can find with win 
8.1 shipped fonts, 1 is bogus (the MS 2003 binary being buggy),
5 freetype already detects and silently works around (2 have an "XXX 
undocumented") - adding a "emit a loud message when this happens" for each of 
those is fairly straight-forward, 1 of the 7 I haven't figure out how to do.

The one I haven't figured out how to do is "INSTCTRL not called from 
pre-program" . Obviously I as a person, know whether I am processing fpgm or 
the glyph proper. Is there a flag within the byte-code interpreter's context 
that says "currently processing fpgm" ? I assume it is somewhere inside.

The other quick question - where in freetype does it keeps track that the 
current glyph is a composite glyph? I am sure it is somewhere, and probably not 
too important (just the glyph id is useful enough to get font designers to go 
fix things...), but the ms 2003 binary's output message includes "composite 
glyph id x" vs "glyph x", so it would be nice to do that too.

Hin-Tak