Why incomplete subscript/superscript alphabet ?

[Khaled Hosny]

On Sat, Oct 01, 2016 at 03:00:50PM +0300, Jukka K. Korpela wrote:
> 1.10.2016, 11:29, Khaled Hosny wrote:
> 
> > On Fri, Sep 30, 2016 at 07:31:58PM +0300, Jukka K. Korpela wrote:
> [...]
> >> What I was pointing at was that when using
> > > rich text or markup, it is complicated or impossible to have typographically
> > > correct glyphs used (even when they exist), whereas the use of Unicode
> > > codepoints for subscript or superscript characters may do that in a much
> > > simpler way.
> > 
> > That is not generally true.
> 
> It is generally true, but not without exceptions.
> 
> > In TeX you get true superscript glyphs by default.
> 
> I suppose you’re right, though I don’t know exactly how TeX implements
> superscripts. I suspect the fonts that TeX normally uses do not contain
> (many) superscript or subscript glyph variants, but TeX might actually map
> e.g. ^2 in math mode to a superscript glyph for 2 (identical with to the
> glyph for ²).

TeX has fonts designed for use at 8pt (size of 1st level scripts) and
5pt (the size of 2nd level scripts) with all the optical correction for
them to look right when scaled down. They provide all the glyphs
provided by the fonts for larger font sizes, so any character can be
used in super or subscripts, no special mapping is needed.

Regards,
Khaled