Re: Combining Box Characters?

From: Leslie Turriff (jlturriff@centurytel.net)
Date: Sun Jan 03 2010 - 18:30:45 CST

  • Next message: Asmus Freytag: "Re: Latin-script keyboard layout (was RE: Quick Question About Korean Input Methods)"

    On Sunday 03 January 2010 16:46:23 Αλέξανδρος Διαμαντίδης wrote:
    > * Leslie Turriff [2010-01-02 20:50]:
    > > I would like to know if it is possible to combine the Box Drawings
    > > Light Horizontal (U+2500) or the Box Drawings Light Vertical
    > > (U+2502) characters with the Box Drawings Light Arc Down and
    > > Left/Down and Right/Up and Left/Up and Right (U+256D-U+2570)
    > > characters to make curving branches?
    >
    > Are you looking for a way to do "Unicode extended ASCII art" with
    > these combinations? If so, I don't think it's possible, or at least
    > practical. There's no widely-supported generic mechanism to do
    > arbitrary combining of spacing characters.
    >
    > If you were outputting text to a paper terminal that allowed
    > overstriking, or a graphical emulation of one, you could maybe do
    > this by backspacing. For example ─<BS>╮ would give a line branching
    > right and down. With a quich web search, I can't find a currently
    > available terminal emulator supporting this... does any? (Isn't this
    > how APL symbols were done once upon a time?)
    >
    > Here's a live example:
    >
    > ─╮ ─╯
    >
    > In an output system using smart fonts, you could do this with
    > zero-width joiner (ZWJ), provided you had a font that turned
    > sequences with ZWJ into the appropriate glyph. Of course no such font
    > currently exists, but it would be possible to create one.
    >
    > ─‍╮ ─‍╯
    >
    > If I misunderstood your question, could you give some more details?
    >
    > Alexandros

    Alexandros,
            Yes, I suppose that "looking for a way to do "Unicode extended
    ASCII art" with these combinations" sums it up well. I'm attaching my
    response to Doug Ewell, who replied privately, since it explains what
    I'm trying to attain.

    Leslie
    =============================================
    Re: [private] Re: Combining Box Characters?
    From:
    Leslie Turriff <jlturriff@centurytel.net>
      To:
    "Doug Ewell" <doug@ewellic.org>
      Date:
    10-01-03 16:15:06
    On Sunday 03 January 2010 14:02:06 you wrote:
    > Leslie Turriff <jlturriff at centurytel dot net> wrote:
    >
    >> I would like to know if it is possible to combine the Box Drawings
    >> Light Horizontal (U+2500) or the Box Drawings Light Vertical (U+2502)
    >> characters with the Box Drawings Light Arc Down and Left/Down and
    >> Right/Up and Left/Up and Right (U+256D-U+2570) characters to make
    >> curving branches?
    >
    > Sure it's possible; they're designed to fit together. How good it
    > looks depends mostly on your font; the arc characters have to exist
    > and be of the right size and spacing. If you want to build a box and
    > put text in it, you'll need to stay away from proportional-spaced
    > fonts altogether.
    >
    >╭─╮
    >│╳│
    >╰─╯
    >
            Certainly, but that does not involve combining characters.
    >
    >> If so, how would one differentiate those combinations from adjacent
    >> pairs of those characters?
    >
    > I don't understand the question. Here are adjacent pairs of the six
    > characters being discussed; nothing really looks to me like it could
    > be confused with something else, except that multiple instances of
    > U+2500 are supposed to connect.
    >
    > ── ││ ╭╭ ╮╮ ╰╰ ╯╯
    >
    > --
    > Doug Ewell | Thornton, Colorado, USA | http://www.ewellic.org
    > RFC 5645, 4645, UTN #14 | ietf-languages @ http://is.gd/2kf0s ­

    Doug,
            First, let me say that I'm just getting started with the exotic
    (to me) endeavour of combining characters. :-)
            Here's an example of the sort of thing I'm trying to do. This
    is what is known as a railroad-track syntax diagram. I have rendered
    it using the sharp-cornered box glyphs (with DejaVu Sans Mono), and
    it works fairly nicely, but I was thinking that it would be clearer if
    the box corners were rounded.

    ►►─CD┬──┬┬──────┬───────────────────────────────────────────────────►◄
         â””d:┘│┌◄─\─┐│ (The string 'CD' followed by an optional drive
             â””â”´path┴┘ designation and an optional path comprising at
                        least one node, with nodes separated by slashes)

            I can use the round-corner glyphs in the places where they
    don't join with horizontal (or sometimes vertical) strokes,

    ►►─CD┬──┬┬──────┬───────────────────────────────────────────────────►◄
         â•°d:╯│╭◄─\─╮│
             â•°â”´path┴╯

    but in other places I would need to combine a horizontal or vertical
    with the appropriate corner glyph to produce a branch or merge of the
    path. A very crudely rendered example is

    >>-CD ---------...--><
           \ /
            -d:-

            My second question refers to the case where a vertical stroke
    and a corner are adjacent, but should not be combined, as with the last
    two glyphs on the second line.
            BTW, In DejaVu Sans Mono the curve glyphs aren't very much
    different from the sharp corners; if you know of a font with more
    pronounced curves I'd appreciate knowing.

    Leslie



    This archive was generated by hypermail 2.1.5 : Sun Jan 03 2010 - 18:33:20 CST