Re: Re: [ft-devel] CFF subfont matrix problem

[Dirck Blaskey]

Werner LEMBERG wrote:
> Hmm.  Please have a look at this thread:
>
>   http://lists.gnu.org/archive/html/freetype-devel/2005-04/msg00059.html
>
> and look at the 2048.cff font which is attached to it.  This is a font
> which converts 2048 to 1000 font units in the subfont, but it lacks a
> top-dict font matrix.
>
> On the other hand, Ding Li's test font from
>
>   http://lists.gnu.org/archive/html/freetype-devel/2008-03/msg00017.html
>
> has a both a top-level and subfont font matrix; the former is the
> standard [0.001 0 0 0.001], while the latter is [1 0 0 1]; with other
> words, it only gives decent results if you concatenate the matrices.
>
> Assuming that both those fonts have been extracted from documents
> which correctly work with Acroread (Ding Li, Dirck, please confirm) I
> assume that it has some heuristic code to either select [1 0 0 1] or
> [0.001 0 0 0.001] as the top-level matrix.
Hi Werner,

The original font in the PDF file worked correctly in Acrobat.
It looks like the PDF file was produced from a OneVision product named 
Asura,
but I don't know what the source material was.

The PLRM mentions that when constructing a CID type 0 composite font,
the upper level font matrix is set to .001 etc and the lower level matrices
are multiplied by 1000.  Not sure how this relates to CFF fonts or how
they are constructed by the relevant tools.

Our system has some heuristics for selecting the 1 or .001 matrix,
but I thought it was an artifact of some other impedance mismatch
problem in our architecture.  It can be quite frustrating.

Wish I could be more helpful,

d