Re: [ft-devel] Support standardized CBDT/CBLC Re: Freetype-devel Digest, Vol 129, Issue 10

[Hin-Tak Leung]

I used the fonts to test support for otspec 2015 features in the project I am 
working on.

I think the spec committee is correct, or at least consistent in bumping the 
version up to 3, even when the new table version is backward compatible (in the 
sense that fonts not using newly introduced features have an identical table 
content except the version field, in this case, the new feature being color). 
They do that when the allowed values changes.

The C* tables allow bit depth 32 (beside 1,2 4,8), and new imageformats 
17,18,19 (besides1-9 except deprecated 3).

They did the same with the os/2 table - v5 is current and larger than v4 and v3 
by two fields. (v3 being the 2009) v3 and v4 are identical except a reserved 
bit field for support of specific locale/language  becomes unreserved and a 
font can claim to support many more lesser-used languages in v4. if your font 
does not support any lesser-used languages, it is identical to v3.

for a font validating program (vs a font using one), using a new feature 
claiming old version is an error or at least a warning, as the allowed ranges 
of values are more restrictive in the older version though.