[luatex] luatex Digest, Vol 57, Issue 6

[Graham Douglas]

Hi Mico

Just a comment on:

"...believe the "glyph" corresponding to the ZWNJ character (hex "200c)
is "invisible", in the sense that it has zero width. Hence, nothing
shows up visually. "

Not quite. (Ignoring CJK fonts which I know nothing about) a glyph with
"zero width" means that it has zero advance width -- ie, it does not
affect the "current horizontal position" in the typesetting engine (or
display) but that does not mean it is "invisible". For example, many
Arabic vowel glyphs also have zero width but, of course, they display
correctly. You can of course use the ZWNJ **character** for various
text-processing applications and never need to actually display it.
Unless your font has the corresponding **glyph** to represent it
visually then, of course, it will not display when using fonts that do
not have a glyph for the ZWNJ. The visual representation of the ZWNJ
character varies quite a lot depending on the font being being used.

Best
Graham