[tex-live] xdvi problems with empty glyph

[Werner LEMBERG]

> What's happening here is that T1lib's T1_SetChar() does return
> without an error (it returns a non-NULL GLYPH pointer), but the
> 'bits' field of the glyph are NULL. This only happens for .notdef or
> whitespace characters, but we couldn't figure out a way to
> distiguish these cases.

What about checking the glyph name?  A glyph called `uni3000' *must*
be retained since it is an ideographic whitespace which has (normally)
exactly the same width as all other CJK characters.

> Since whitespace characters are really rare in `ordinary' fonts
> (they practically don't exist),

They do exist.  *All* CJK fonts contain at least one such whitespace
glyph.  For a quarter of the world's population, CJK fonts are the
`ordinary' ones :-)

> That probably means that we'd need to look at the encoding vector to
> decide whether it's really .notdef,

Yep.

> but I don't know yet how to do this e.g. for a font with built-in
> encoding (using T1lib?).

Me neither, sorry.


    Werner