Defining Alternative Glyphs

Greetings!

I think there may be two separate cases that are being covered by the 
term "alternative" glyphs.

Properly speaking, Unicode points represent characters and not glyphs, 
so any glyph associated with a character is a matter of the font you 
choose and not an "alternative glyph." To say "alternative" glyph 
implies there is some default glyph, which is not true. The glyphs shown 
in the Unicode standard are illustrative only.

The first case for "alternative" glyphs is where I wish to specify a 
particular glyph for a character but other that perhaps being 
unattractive display, the information content of the text is the same. 
Choosing any of the Latin fonts would be a good example.

The second case and I am not sure how often it would come up, would be 
where I use a particular code point, say for Middle Egyptian, but I want 
a particular glyph, which was used for that character in a particular 
historic period or type of text, and not some other glyph for that 
character. While it is true that it is the "same" character, the meaning 
on of the text would be changed if another glyph were substituted for 
the one I specify. Typically that sort of additional information is left 
by Unicode to the markup layer.

Rather than saying "alternative" glyphs I think it would be more 
accurate to speak of specifying a particular glyph or set of glyphs for 
some portion of text.

Considered that way, how it that different from specifying a specific 
font be used with some particular span of text?

Hope everyone is having a great day!

Patrick

-- 
Patrick Durusau

Chair, V1 - US TAG to JTC 1/SC 34
Convener, JTC 1/SC 34/WG 3 (Topic Maps)
Editor, OpenDocument Format TC (OASIS), Project Editor ISO/IEC 26300
Co-Editor, ISO/IEC 13250-1, 13250-5 (Topic Maps)