Re: Characters in Private Use Area

From: peter_constable@sil.org
Date: Tue Aug 24 1999 - 15:20:14 EDT


       Adobe uses U+F634 - U+F8FE. You can find details at

       http:
       //partners.adobe.com/asn/developer/typeforum/corporateuse.txt

       In their documents, they talk about the "Corporate Use subarea"
       in a way that suggests that there is some officially sanctioned
       organisation of portions of the PUA. The Unicode 2.0 book does
       talk about "the Corporate Use subarea", but that term is
       nowhere given any further definition except to say that the
       "Corporate" portion begins at the top, U+F8FF, and extends
       down, and that the "end user" portion begins at the bottom,
       U+E000, and extends upward. You have to decide where you fit
       best. (Or you may be like some of us who anticipate that we may
       need the whole lot, and hope that the commercial software that
       we use doesn't conflict with that.)

       Adobe has promoted a coordinated use of the "Corporate Use
       subarea" among big players:

       "In fact, we envision the CUS as a collaborative effort among
       vendors, wherein each vendor ensures that new assignments do
       not overlap with existing ones. This shared approach ensures
       optimal use of the limited UVs available. It also avoids the
       obvious problems that applications would have in identifying
       the vendor of a font in order to determine which vendor's CUS
       assignments were in effect."

       (From http:
       //partners.adobe.com/asn/developer/typeforum/unicodegn.html#4.b
       )

       I personally am not encouraged by this since I'd rather see
       commercial software developers leave the use of the PUA
       entirely up to end users, except perhaps for data that will
       only ever be processed within their app. (E.g., if you were
       trying to develop a new way to write a language - e.g. ASL, or
       English with ideographs - and you needed, say, 5847 codepoints,
       and you were trying to create documents using your script in
       the hope of promoting use of your creation and were using
       Pagemaker to do so, you'd probably be a little frustrated if
       Pagemaker was doing something like insisting on printing U+F66E
       as nothing or as a-macron instead of your custom glyph that you
       laboured so hard to create.) Fortunately, I have seen no
       indication that any other 3rd party developer is trying to
       divvy up the PUA in this way, and Adobe themselves appear to
       suggest (though it's not completely clear) that this would only
       be temporary:

       "In addition, we regard CUS assignments as useful until
       OpenType features become widely available in fonts and
       supported by applications."

       (op cit)

       In the same document, they provide the following information
       about others' use of the PUA:

       "Apple has published CUS assignments in the range U+F800
       through U+F8FF. Adobe uses CUS assignments in the range U+F600
       through U+F7FF, as well as the same assignments for some
       characters in Symbol and Zapf Dingbats from the Apple-defined
       range. Microsoft is treating the range U+F000 through U+F0FF as
       the definition of its symbol code page."

       Peter



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