Re: JavaScript & Fonts

From: Jukka K. Korpela (
Date: Mon Nov 02 2009 - 02:01:27 CST

  • Next message: "Re: JavaScript & Fonts" wrote:

    >> Thanks, Van, I will try to be patient waiting for an answer.
    >> Mike
    > Dear lord, I think I just came up with an answer for you.

    Well, for one thing, you are not answering the question asked and did not
    quote it either. It was: “Is there a way within a JavaScript program to
    enumerate all of the available fonts on a system and then to check them for
    support for a particular Unicode character?” To my knowledge, the correct
    answer is “No,” but JavaScript exists in many versions and implementations,
    some of them with some tricky ways of extracting information from the
    system, though perhaps blocked from that by security settings.

    > Microsoft's
    > Web Embedding Fonts Tool allows you to create an object that is
    > downloaded with your website and used to display the page.

    That does not answer the question, though it might answer a question that
    might be asked after hearing the answer to the first question.

    However, WEFT hasn’t got much popularity (you can hardly find pages that
    really use it, as opposite to trivial pages created just to demonstrate, in
    a simple setting, that WEFT “works”). One reason to this is the common
    experience that when you try to use it for real, you run into
    difficulties—odd problems and limitations. Another reason is that it is a
    Microsoft-only technology, which hasn’t been developed much in the recent

    The font embedding techniques as defined in CSS 3 drafts sound more
    promising. They are supported by newest versions of Firefox and Opera, and
    using suitable utilities you can convert a font to the format required by
    WEFT and thereby cover IE as well. For an introduction, check e.g. . However, this is not
    something I would do in a case like this.

    If you only need to use one character that is not commonly available in
    fonts that people have, it would be rather inefficient to embed the Arial
    Unicode MS font or the Code2000 font (both of which are rather large) just
    for that. Many visitors just wouldn’t wait.

    By the way, it is rather easy to get a quick idea of font coverage for a
    character, if you are willing to rely on sources that are not authoritative
    and comprehensive, just pretty good:

    In the case of CUBE ROOT, there’s the additional problem that if the user’s
    system has a font containing it, then the font is most probably Arial
    Unicode MS (shipped with Microsoft Office and other products). In that font,
    the glyph of the character is barely legible in the font size used (on a
    high-quality display, though looked at with by less than high-quality eyes).

    My conclusion is that in cases like this, an author should create a suitable
    image of the character, in the intended environment–in practice, a button of
    the same style as those based on characters when rendered in a typical way.
    That is, to take an image of the button rendered using some nice font
    (DejaVu Sans?) and edit it in a graphics program to make it somewhat more


    This archive was generated by hypermail 2.1.5 : Sun Nov 01 2009 - 21:04:22 CST