[tex-live] bug in dvipdfmx wrt diacritics?

[Jonathan Kew]

On 10 Sep 2011, at 00:41, Reinhard Kotucha wrote:

> The error message
> 
> ** WARNING ** Obsolete four arguments of "endchar" will be used for
> Type 1 "seac" operator.
> 
> doesn't mention only seac but also endchar.  Since seac doesn't use
> endchar itself, I suppose that dvipdfmx has problems with the glyphs
> supposed to be combined, rather than with the seac routine itself.
> 
> In order to find out what the `four arguments of "endchar"' are, you
> have to stop the program when endchar is called and see what's on the
> stack at this time.

I think this must be referring to the feature described in Appendix C (Compatibility and Deprecated Operators) of the Type 2 Charstring Format spec, available from http://download.microsoft.com/download/8/0/1/801a191c-029d-4af3-9642-555f6fe514ee/type2.pdf, or no doubt somewhere on Adobe's site. 

Interestingly, I don't see any mention of this feature in the Adobe Type 1 Font Format spec at http://partners.adobe.com/public/developer/en/font/T1_SPEC.PDF,  which seems to imply that it is very much obsolete/deprecated.

It seems that in certain circumstances, when (x)dvipdfmx is converting glyphs from a Type 1 font to Type 2 charstrings, it tries to use this obsolete feature, and apparently some PDF readers choke on the result.

I'm not sure why (x)dvipdfmx does this, or how easy it would be to modify the code to avoid this issue; I haven't ever studied or understood all this font-handling code in detail. Perhaps ChoF could offer some advice?

JK