[HarfBuzz] Don't render control characters?

[mskala at ansuz.sooke.bc.ca]

On Thu, 6 Mar 2014, Richard Wordingham wrote:
> On Thu, 6 Mar 2014 22:38:07 +0200
> Konstantin Ritt <ritt.ks at gmail.com> wrote:
>
> > Did you meet any single font with glyph for U+0008 (BS)? Honestly, I
> > don't imagine what U+0008 glyph representation looks like :)
>
> Back one space!  The underlining in Unix man pages is usually
> implemented as overstrike via U+0008.  However, I'd forgotten that
> OpenType advance widths can't be negative, so it can't be rendered
> under font control.

ECMA-17, or ISO 2047, is now withdrawn, but it specified a graphical
symbol for the control character we now call U+0008.  The symbol
looked like an arrow running from lower right to upper left, with a
slight concave-downward curve.  You can find a copy of the document here:
   http://www.ecma-international.org/publications/files/ECMA-ST-WITHDRAWN/ECMA-17,%201st%20Edition,%20November%201968.pdf

-- 
Matthew Skala
mskala at ansuz.sooke.bc.ca                 People before principles.
http://ansuz.sooke.bc.ca/