Re: U+25CA LOZENGE - why is it in the "Mac OS Roman" character set (and therefore widespread in current fonts)?

On 8/13/2012 12:50 PM, Asmus Freytag wrote:
> In that context, you can't distinguish a lozenge from a squished
> diamond (*) from a diamond suit symbol.
>
> While the character is one a of a set, it was not uncommon to have
> people make do with somewhat similar characters standing in for each
> other. In the early years such "unifications" were, if not encouraged,
> then widely tolerated.
>
> So, even if the lozenge, as such, may not have been in CP437, anyone
> who wanted to display one, would have used the card suit.

Sure. Just like people regularly conflated the Greek letter beta and
German esszet (E1) in CP437,
which was placed between lowercase alpha (E0) and uppercase gamma (E2),
just to
further confuse everybody. ;-)

But I wasn't looking at the screen of a 1984 vintage IBM PC in this case
-- I was looking
at the IBM Corporate Specification for character sets, which identifies
CP437 position 04
as SS030000 "Diamond Suit Symbol". (And at high quality laser font
documentation.)

Incidentally, while people may have attempted to use CP437 04 as a
lozenge instead
of a card suit, in the 1980's they would have had little to no success
in trying to exchange
it, because the IBM PC overloaded the C0 positions in CP437 for screen
display. So
programs could poke 04 to the screen display to show a diamond shape,
but when you
tried to use that as an interchangeable character you usually ended up
with garbage
instead.

--Ken
Received on Mon Aug 13 2012 - 15:37:15 CDT