I dd not speak about inter-word spacing (this cont affect the
rendering of ellipsis itself) but about inter-letter spacing.
But the context I provided was that some people ask for ". . .[ .]", as
ugly as it is :-) And, again, the precise "ideal" spacing is a matter of
typographic design; you can probably deal with this via kerning tables.
Once you've increased the width of these interword spaces to their
maximum, all the characters (and these increased spaces) should be
justified using interletter spacing, and this extra interletter
spacing should be applied as well between the dots of the ellipsis
(showing that they are effectively 3 separate characters and not just
one with a fixed distance between dots).
You are right that tracking and glyph scaling exist, but how exactly
they should be applied to a 3- or 4-dot ellipsis is likely a matter of
font design and typographic style. What you write isn't unreasonable,
but I don't buy it as an absolute prescription. (If it were one, that'd
be an argument against a single-glyph ellipsis.)
If one wants to really avoid this expansion of ellipsis during
justification (cases that should be rarely desired), we could use
<period,ZWJ,period,ZWJ,period>, possibly surrounded with (unbreakable)
fixed-width narrow spaces, to hint their behavior as a single
(unbreakable) ligature. But may be this is the (rare) usage intended
by the single-character ELLIPSIS (but we know the caveats of this
character if it is mapped with a single glyph in monospaced fonts)
Maybe ... and the origin of the single-glyph ellipsis remains a mystery
to me.
Stephan
