Re: [Freetype] Ambiguously Undefined Glyphs [was: Mozilla needs someinfo on Xft]

[Brian Stell]

Antoine Leca wrote:
> ...
> I believe David (and his family) would be pleased if we wait until
> he comes back "officially" from his holydays, but never minds...

David: Please take you time. I have working (demo grade) code.
I am not stuck at present. Any discussion of new FreeType2 features 
can easily wait till after your vacation.

There is agreement that FreeType2 should be used.

The current discussion is primarily driven by exactly how Xft fits
with Mozilla.

> > Any plans to make the LOCA table available?

Lets postpone discussing this till David is back from vacation.

> What is the point to make 'loca' available? I understand this means
> you will be able to know if some glyphId is "empty" (i.e. if its
> location is the same as the location of the following one), but it may
> also happens that it may be "blank", that is a "real" glyph, with a
> bounding box and perhaps instructions, but... 0 countours... (and yes,
> this makes sense, for example if you want to have instructions that
> act upon the advance). Which then needs to investigate 'glyf'!
> (a whole lot merrier problem, IMHO)

Currently in the code in the Windows version of Mozilla checks the
LOCA table as I indicated and I do not know of any bug reports.

Not having bug reports, of course, does not necessarily mean the
test could not be improved.

> I believe it might help if you can enhance a
> bit your test program, and record which are the characters that
> according to your test program ought to be glyphed and are not in
> the fonts. I am quite sure there are very basic explanations for 
> a number of them, explanations which do not need anything at 'loca' 
> level to be handled correctly. 

Let me know which font(s) you would like information on and I will
produce the map and if it is small I will post it; if it is large
I will email it to anyone that would like it.

> As a side point, I believe what you are proposing (i.e., sorting 
> glyphs in or out based on properties derived from the character 
> codes) does not belong to the Freetype library, but to the layout 
> one (that is intended to be a layer above). But I might easily 
> be wrong.

It is needed somewhere. Currently Mozilla does it at the application 
layer. Because my current test is CPU intensive it could not be done
at on-the-fly or even at startup. Thus I ended up needing to save the
information in a catalog.

Lets postpone discussing where it best fits till David is back from 
vacation.

-- 
Brian Stell
mailto:address@hidden