Re: Display of Isolated Nonspacing Marks (was Re: Questions on ZWNBS...)

From: Peter Kirk (peter.r.kirk@ntlworld.com)
Date: Wed Aug 06 2003 - 16:11:22 EDT

  • Next message: John Cowan: "Conflicting principles"

    On 06/08/2003 05:58, Jony Rosenne wrote:

    >I would like to point out that with all due respect, how particular fonts or rendering engines behave is only marginally relevant to the Unicode list. I think that we should deal only with the Unicode specification.
    >
    >A particular implementation or many implementations may not behave as expected, and then may be either conformant or non-conformant, or may behave as expected and still be either conformant or non-conformant. Messages such as the attached help the discussion of the specification only as illustrations and as a basis for discussing conformity.
    >
    >Jony
    >
    >
    >
    >>-----Original Message-----
    >>From: unicode-bounce@unicode.org
    >>[mailto:unicode-bounce@unicode.org] On Behalf Of Peter Kirk
    >>Sent: Wednesday, August 06, 2003 12:11 PM
    >>To: Curtis Clark
    >>Cc: Unicode List
    >>Subject: Re: Display of Isolated Nonspacing Marks (was Re:
    >>Questions on ZWNBS...)
    >>
    >>
    >>On 05/08/2003 16:59, Curtis Clark wrote:
    >>
    >>
    >>
    >>>on 2003-08-05 15:31 Peter Kirk wrote:
    >>>
    >>>
    >>>
    >>>>Thank you, Mark. This helps to clarify things, but still doesn't
    >>>>explicitly answer my question of how to encode "a sentence
    >>>>
    >>>>
    >>like "In
    >>
    >>
    >>>>this language the diacritic ^ may appear above the letters
    >>>>
    >>>>
    >>...", but
    >>
    >>
    >>>>instead of ^ I want to use a combining character" and want to
    >>>>display exactly one space before the combining character - do I
    >>>>encode two spaces or one?
    >>>>
    >>>>
    >>>In this language the diacritic ĚŠ may appear above the letters...
    >>>
    >>>Two spaces, at least in Thunderbird Mail.
    >>>
    >>>
    >>>
    >>>
    >>Thank you. Well, this sort of works. I looked in various
    >>fonts. In some
    >>of them the diacritic is centred in the space between the words
    >>"diacritic" and "may", but in others it is offset to the left or the
    >>right. The problem is that the space is wider than the
    >>diacritic, which
    >>confuses things, and all the more so no doubt if it expands for
    >>justification. NBSP would probably be a better choice in that
    >>it is less
    >>likely to expand. But what I am looking for is a diacritic
    >>holder which
    >>is defined to be only as wide as the diacritic. On the principle that
    >>base characters expand to fit the width of the diacritic, ZWSP or,
    >>better, a real (rather than misnamed) zero width no break space would
    >>seem to have the right properties for that.
    >>
    >>--
    >>Peter Kirk
    >>peter.r.kirk@ntlworld.com
    >>http://web.onetel.net.uk/~peterkirk/
    >>
    >>
    >>
    >>
    >>
    >>
    >>
    >
    >
    >
    >
    >
    Point taken. But when different fonts and rendering engines give
    different results because the standard is unclear or ambiguous, that is
    a matter for the discussion here. And when conforming fonts and
    rendering engines fail to give the required results, that may also be
    because of a deficiency in the standard.

    It seems that many rendering engines give to the sequence space,
    combining mark the width normally assigned to a space. Is this actually
    what the standard suggests? I have identified a need to display
    combining marks with no extra width, only the width required by the
    mark. Should the sequence space, combining mark do what I want, or
    shouldn't it? If so, this needs to be spelled out so that rendering
    engines know what they are supposed to do. If not, there may be a need
    for a new character. This is a deficiency in the standard, not in the
    rendering engines.

    -- 
    Peter Kirk
    peter.r.kirk@ntlworld.com
    http://web.onetel.net.uk/~peterkirk/
    


    This archive was generated by hypermail 2.1.5 : Wed Aug 06 2003 - 16:51:15 EDT