RE: Glyph Selection in Absence of Variant Selectors

From: Peter Constable (
Date: Mon Feb 27 2006 - 08:58:44 CST

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    > From: [] On
    > Behalf Of Richard Wordingham

    > If the form of a
    > character may be selected by a variant selector, is its form nevertheless
    > specified to the same degree if no variant selector appears?


    > One
    > possibility is that the renderer is free (within the constraints set by
    > specifications by other means, e.g. 'features', 'language', etc.) to
    > choose the form according to the renderer's author's taste and inclination
    > (e.g. programming time constraints).

    That is the case (though it's more likely going to be a type designer rather than programmer that's involved).

    > The other is that the Unicode standard
    > should specify the selection.

    The Standard does not specify exact appearance of characters. It only specifies an exact abstract character identity; a representative glyph is provided, but a range of accepted appearances is assumed.

    > (The notorious example is
    > breaking a conjunct in Devanagari - an author cannot immediately see
    > whether it was he or the
    > font+renderer that chose to use a half-form.)

    You asked about default glyphs for characters; the effects of Indic encoding mechanisms that control conjunct formation is quite another matter.

    Peter Constable

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