Re: Generic base characters

From: Kenneth Whistler (
Date: Mon Jul 16 2007 - 18:22:38 CDT

  • Next message: John H. Jenkins: "Re: Generic base characters"

    Raymond Mercier responded:

    > > One reasonable position to take is that aksaras in a complex
    > > Indic script outside the canonical structuring rules for an aksara
    > > should be rendered with fallbacks that treat each combining
    > > mark that doesn't "fit" as a separate layout unit:
    > >
    > > {MA + O}, {O}, {O}
    > >
    > > And then you have to decide how to display those two extra
    > > matras that don't have an effective base (even though
    > > formally, of course, MA is the base character of the
    > > combining character sequence here).
    > These and the other remarks assume that vowels are typed as medials, but if
    > you wanted to you could write MAOOO or MAIII simply enough in Nagari,
    > without runing into ligature problems: मओओओ मइइइ .

    Sure... if you use the independent vowels you don't have a
    rendering problem, because those by definition start
    a new aksara, and the rendering engine simply has a sequence
    of well-defined aksaras to render. Easy.

    But I wasn't actually concerned about how the "vowels are typed",
    but rather simply with what does a rendering engine do with
    a sequence such as:

    <092E, 093F, 093F, 093F> ( MA + I + I + I)

    *regardless* of how it got to be that way: by deliberate typing,
    by a hard-coded string array, by misbehaving software erroneously
    deleting consonants -- whatever.

    The problem is: given that (valid, legal) Unicode string, what
    output display would I expect from a Unicode rendering engine,
    and why.

    And a practical companion problem is to determine what actual
    behavior and user expectations are among Nagari users for
    prosodic effects like these (and other kinds of odd extensions
    to writing). What is actual practice in Nagarai for writing
    the equivalent of maaaaaaa or miiiiiiii or muuuuuuu? If
    people just write the aksara "ma" or "mi" or "mu" and then
    suffix a long list of the independent vowels, then we don't
    have a problem matching what people expect. But if there is
    any practice of stacking matras with the same intent, then
    the rendering engines will have a problem with that.


    This archive was generated by hypermail 2.1.5 : Mon Jul 16 2007 - 18:24:28 CDT