[ft-devel] Bug? Font that fontforge shows but freetype does not (Re: Freetype-devel Digest, Vol 149, Issue 17)

[Hin-Tak Leung]

> I guess the font is kind of buggy since
 newer versions of it i can find in the 
 internet render fine (i think this is
 an old version)
 
> But since it's still floating around,
 and fontforge seems to render it fine 
 maybe it can be fixed to render in
 freetype?
 

The difference is simple - fontforge ignores hinting instructions. If you 
switch off hinting in freetype, that it loads also. FT_LOAD_NO_HINTING , or 
press h in ftview.

Hmm, we seems to have a serious problem - the above describes freetype 2.8; 
freetype git won't load the font with or without hinting.

This is what the python wrapper of the font validator backend (based on current 
freetype git) says :

('Size 10, PushB[0], Pre-Program, At ByteOffset 0', ':', 'E6045', 'Stack 
Overflow')
('Size 10, PushB[2], Pre-Program, At ByteOffset 1', ':', 'E6045', 'Stack 
Overflow')
('Size 10, MPPEM, Pre-Program, At ByteOffset 5', ':', 'E6045', 'Stack Overflow')
('Size 10, WS, Pre-Program, At ByteOffset 6', ':', 'E6045', 'Stack Overflow')
('Size 10, WS, Pre-Program, At ByteOffset 6', ':', 'E6047', 'Storage index out 
of range')
('Size 10, WS, Pre-Program, At ByteOffset 7', ':', 'E6047', 'Storage index out 
of range')
...
piles of errors....
...
('Size 10, WS, Pre-Program, At ByteOffset 74', ':', 'E6047', 'Storage index out 
of range')
('Size 10, JMPR, Pre-Program, At ByteOffset 8', ':', 'E6071', 'Execution time 
too long and exceeds dynamic limit in backward jump')

So basically the hinting instruction in the prep table is trash, and also there 
is a backward jump loop in the hinting instruction. The backward jump check was 
added in freetype recently, so this example why freetype 2.8 is happier.