On 5/29/2013 9:53 AM, Manuel Strehl wrote:
Out of curiosity, has it happened before, that a glyph was updated
(i.e., substantially changed) in the standard?
Yes, Philippe gives some examples of typical situations.
Representative glyphs are not immutable - what is immutable is the
"identity" of the character that is encoded. A change in representative
glyph that affects the perception of that identity in an adverse way,
must be avoided, but, in reverse, a glyph that leads to
misidentification of a character can, and in typical situations, also
should be corrected.
For symbol, the identity of the character does not necessarily exist
independently of its shape. Two similar shapes may exist where each is
used only in some context, or where the usage contexts only partially
overlap. If that is the case, it should be questioned whether this is
really a matter of two representations of the same character, or whether
it is the case of two characters that happen to be related.
For letters, you have the word context that allows you to resolve the
identity question. For symbols, there is no such single, overriding context.
A./
