Re: how to add all latin (and greek) subscripts

From: Kenneth Whistler (kenw@sybase.com)
Date: Tue Jul 01 2008 - 21:15:44 CDT

  • Next message: Michael Everson: "Re: Capital Sharp S in the News"

    Doug Ewell noted:

    > http://www.ecma-international.org/publications/files/ECMA-ST/Ecma-048.pdf
    >
    > There's a LOT more to the so-called "ANSI" terminal sequences than just
    > changing colors and moving the cursor around. There may be one or more
    > existing sequences that do what you want.

    In particular, note:

    8.3.93 PLU - PARTIAL LINE BACKWARD

      "... This offset should be sufficient either to image following
      characters as superscripts until the first following occurrence
      of PARTIAL LINE FORWARD (PLD) in the data stream, or, if
      preceding characters were imaged as subscripts, to restore imaging
      of following characters to the active line (the line that contains
      the active presentation position)."
      
    and of course, the symmetric discussion for:

    8.3.92 PLD - PARTIAL LINE FORWARD

    And if you want to control the size of font, to make the super/subscripts
    display some percentage smaller than the normal text, that is what
    the following control is for:

    8.3.55 GSM - GRAPHIC SIZE MODIFICATION

      "... GSM is used to modify for subsequent text the height and/or
      the width of all primary and alternative fonts identified by
      FONT SELECTION (FNT) and established by GRAPHIC SIZE SELECTION (GSS).
      The established values remain in effect until the next
      occurrence of GSM or GSS in the data stream."

    > Of course, not every terminal
    > will support them, but you've got a far better chance of finding a
    > terminal that does support existing standard sequences than getting
    > brand-new sequences approved by international bodies, and then getting
    > terminal vendors to support those.

    Exactly... particularly since the established control function
    standard already has full provision for these. Note that PLD and PLU
    are actually part of the most commonly implemented C1 control
    set. See Unicode values:

    U+008B = PARTIAL LINE FORWARD
    U+008C = PARTIAL LINE BACKWARD

    The graphic size controls are not, however.

    If a terminal (or a terminal emulation) doesn't support
    these existing functions, the chance
    of getting additional (and superfluous) controls added to
    the standard and then getting that terminal (or terminal emulation)
    to support those new functions is pretty remote.

    Go with what you've got available, and see who actually thinks
    it is worthwhile to go to the effort to support them in
    terminal implementations.

    --Ken

    This archive was generated by hypermail 2.1.5 : Tue Jul 01 2008 - 21:20:06 CDT