Could Unicode deliver the level of paleographic detail needed for encoding ancient Egyptian hieroglyphs?

[James Kass]

On 2024-03-04 8:44 PM, Asmus Freytag via Unicode wrote:
> What you are describing is rich text. Anytime you add "special 
> commands", no matter how you encode them, you have rich text. (There 
> is a small amount of gray zone, in which characters like SHY, NBSP and 
> TAB can be understood as still being "plain text", but a syntax for a 
> virtual rotation machine is definitely beyond the scope).
>
> A./

Egyptologists were (and are) involved in the process to encode 
hieroglyphics.  Any shortcomings in the encoding should be addressed by 
those experts.  People involved in the decisions understand the needs of 
the user community as well as the Unicode principals for character 
encoding.  The document makes a convincing argument against enabling a 
plethora of rotations willy-nilly at the plain-text level.

Plain-text legibility is the issue for Unicode.  Whether there is a 
semantic difference between a glyph rotated by 48 degrees and one 
rotated by 49 degrees is not for me to say, but it seems unlikely. It is 
up to the experts to determine whether a string of hieroglyphic 
characters is legible.  So it would be the better practice to first 
determine how the user community is handling any issue before devising 
any mark-up scheme just because somebody might consider it useful some day.

Regardless of whether fine glyph rotation gets handled at the plain-text 
or rich-text level, one of the arguments against fine rotation appears 
to be based on a misconception related to fonts and rendering.

Here's one example of this misconception from the document:
https://www.unicode.org/L2/L2024/24045-ancient-egyptian-rotations.pdf

"Rotations entail a stark increase in the size of OpenType fonts, as 
such fonts cannot dynamically rotate glyphs, and therefore need to store 
rotated copies. To avoid the blow-up in size that would result if all 
rotations for all signs were included, a selection of rotations for a 
selection of signs is registered, and fonts would only be expected to 
implement those."

Glyph data in TrueType/Open Type fonts is stored as a series of 
Cartesian points.  Rotation by any valid degree is accomplished by 
formula.  The font engine is the logical place for implementing any 
transformative formula, for example - font size.  Thus, any glyph from 
any font could be rotated by any degree dynamically with no impact on 
the font file size.