Re: [Devel] Fonts with glyphs containing zero contours

[Detlef Würkner]

address@hidden (Keith Packard) wrote:

> Around 16 o'clock on Feb 7, Detlef Würkner wrote:
> 
> > The glyphs are there. Not as outlines, but as embedded sfnt bitmaps.
> > Since using embedded bitmaps if possible is default, it is reasonable
> > that the glyph codes are listed in the unicode map.
> 
> Oops. I fixed my sample to load with NO_BITMAP and found the outlines 
> present in the courier font.  
> 
> Now I'm having trouble with msmincho.ttf (http://keithp.com/~keithp/fonts/
> msmincho.ttf).   This font has no fixed sizes; face->num_sbit_strikes is 0
> so there really aren't any bitmaps associated with the font.
> 
> Loading glyphs from this font, I discover that out of 12481 glyphs,
> I find some 4888 glyphs (other than space/nbsp) that load as outline
> glyphs, but with zero contours.  Most of these "broken" glyphs occur in 
> the Unicode CJK space.

Maybe this font is broken. I have a msmincho.ttc (~9MB) and a
msmincho.ttf (~5MB) with MS copyright that contain many embedded sfnt
bitmaps, your version (~3MB) might be generated by a converter that
stripped the copyright notice and the bitmaps without correcting the
charmap if no outline was there?

> Scanning the 9364 .ttf font files I found on my machine, I note that many 
> of them have glyphs of this form.  I presume there are additional Unicode 
> glyphs which are supposed to be blank, but a hundred of these fonts
> have more than 100 "broken" glyphs.

Sorry, my MC68060/50MHz is probably too slow for such tests :)

> > If you want contours only, you must include the FT_LOAD_NO_BITMAP flag.
> 
> No, what I'm after is building an accurate Unicode map; I need to know the 
> list of glyphs that I can display at an arbitrary size -- those 
> displayable only at certain fixed sizes are essentially useless.  I'm 
> hoping that fonts don't do that; but I guess I should probably prepare for 
> such contingencies.

Maybe Davids suggestions can help you.

While answering to you, can you confirm that the two versions of accelerator
tables saved in a PCF file never contain *compressed* metrics? If yes, could
create another patch... And have you read that the AVERAGE_WIDTH property
in some XFree86 BDF fonts is a string, not an integer ("144" not 144)?

Ciao, Detlef
-- 
_ // address@hidden
\X/  Detlef Wuerkner, Langgoens/Germany