[ft-devel] what old/new FontVal says about these fonts (Re: FreeType unable to open some fonts which can be opened by some font viewers (Re: Freetype-devel Digest, Vol 143, Issue 9))

[Hin-Tak Leung]

I didn't touch the *.fon's - FontVal old or new does not load them at all, so 
no point.

Interestingly only 4 of the 29 font files fail to load with the older 1.0 
proprietary backend.

15.ttf =Secure Rasterizer error: Point out of range
22.ttc =Negative seek
26.ttc =Secure Rasterizer error: TrueType stack underflow
6.ttf =Rasterizer error: Error reading from font, bad offset or length

6 of 29 (notes some overlap with above) - causes the full table validation to 
fail before getting to the rastering backend:

15.ttf
24.ttc
26.ttc
2.otf
5.ttf
8.ttf

24.ttc won't work even skipping all the table tests.

5 of them has CFF outlines (which the backend does not process) - but the CFF 
test does mostly tell you what is broken about them:
13.ttf
1.otf
3.otf
4.otf
7.ttf

2.otf is apparently also a rather broken CFF.

I think 13.ttf and 1.otf can be better - the rest, the CFF table test tells you 
what's wrong.

So yes, rather interestingly, the older FontVal 1.0 backend from Microsoft is 
happy to read 18 of the 23 (18 = 29 - 6 (CFF) - 4  - 1 [24.ttc]), which is a 
lot happy than FreeType's 4-9 of 23. the backend I was running is a heavily 
patched derivative of  bcae657482ca038dc2b7c4ddd737a110c85e052a . Let's say it 
is a 3 weeks' old freetype.

The 14 files which 3-week's-old FreeType not happy are: (note uncertainty with 
the 5 files, 15.ttf, 24.ttc, 26.ttc, 5.ttf, 8.ttf, which caused the full test 
to fail before it gets to the FreeType part)

10.ttf.report.xml:<Report ErrorType="FreeType error: Unknown file format
11.ttf.report.xml:<Report ErrorType="FreeType error: Broken file
14.ttf.report.xml:<Report ErrorType="FreeType error: Horizontal metrics (hmtx) 
table missing
17.ttf.report.xml:<Report ErrorType="FreeType error: Broken table
19.ttf.report.xml:<Report ErrorType="FreeType error: Unknown file format
21.ttf.report.xml:<Report ErrorType="FreeType error: Broken table
22.ttc.report.xml:<Report ErrorType="FreeType error: Too many hints
23.ttc.report.xml:<Report ErrorType="FreeType error: Broken table
25.ttc.report.xml:<Report ErrorType="FreeType error: Broken table
27.ttc.report.xml:<Report ErrorType="FreeType error: Broken table
28.ttc.report.xml:<Report ErrorType="FreeType error: Broken table
29.ttc.report.xml:<Report ErrorType="FreeType error: Broken table
6.ttf.report.xml:<Report ErrorType="FreeType error: Broken file
9.ttf.report.xml:<Report ErrorType="FreeType error: Broken table

I'll re-run at some point, but it won't be any time soon... and thanks for a 
set of wonderfully broken font files :-).