In light of our recent discussion on Latin ligatures, I just
thought some of you (who don't subscribe to the OT list) would
find it interesting to see a glimpse of a slightly related
(though, so far, rather shorter) thread happening on another
list:
---------------------- Forwarded by Peter
Constable/IntlAdmin/WCT on 12/30/99 02:56 AM
---------------------------
From: <opentype@list.sirius.com> AT Internet on 12/30/99 02:21
AM
Received on: 12/30/99
Subject: Re: Letter Spacing and ligature formation
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[original message, Chris Fynn author]
In OT tables there a way of specifying when two or more
successive characters should / should not be rendered by a
ligature glyph based on letter spacing? For instance you
normally might want to display the characters 'f' 'f' 'i' using
a ligature "ffi" in normal letter spacing but if the user
increased the letter spacing( > a given value) you might want
each of these characters to be displayed as discrete glyphs.
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[sub-thread 1]
Really Clive? Xpress will turn off f-ligs if there is
greater than a certain amount of tracking?
Could you give us more details? (Personally,
I never could get automatic fi/fl substitution
to work reliably in Xpress anyway, and always
just enter the characters in by hand. Besides,
in most cases, using just fi/fl is worse than using
no ligatures at all. What genius thought up this
fi/fl only business? Was it someone at Lino?
Does anyone know the details?
At 12/27/99 02:52 PM, Clive Bruton wrote:
>Bill Troop wrote at 27/12/99 18:54
>
> >Yes indeed! How well I remember what fun it was,
> >in Lightning DrawGX, to see for example how the ffl
> >ligature would magically change into f f l when you
> >applied tracking to the line. What a brilliant program!!!!
>
>Ahem, yes, it would have been stunning if XPress hadn't been
doing it for >years before that (fi, fl ligs only of course).
>
>
>-- Clive
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[sub-thread 2]
Are you saying that we _can't_ do what we could do
so easily in GX, namely, automatically substitute
all five (say) f-ligs, and automatically un-substitute
if positive line tracking is now applied that would
normally position the characters with greater than x
amount of additional space between them? If that is
the case, then ligature substitution in OT-enabled apps
will not be an attractive option. In fact, it won't even
be viable. Or do I simply misunderstand you?
(I certainly hope I do!) (And isn't it a little late to be
finding out these things?) (And speaking of finding
things out late, what does OT do to flipper fonts
and random fonts, i.e. Kosmik, Beow_lf, etc.?)
At 12/28/99 05:17 PM, you wrote:
>No, target strings of glyphs cannot be matched on the basis of
positioning >info in any way that I can think of. I find that
a good way to remember >what can be done is to remember David
Opstad's characterization of the >OpenType GSUB and GPOS
methods for matching a target string, as being >basically
simple regular expressions for matching text.
>
>
>At 4:08 PM +0000 12/27/99, Christopher John Fynn wrote:
> >In OT tables there a way of specifying when two or more
successive > >characters should / should not be rendered by a
ligature glyph based on > >letter spacing? For instance you
normally might want to display the > >characters 'f' 'f' 'i'
using a ligature "ffi" in normal letter spacing but > >if the
user increased the letter spacing( > a given value) you might
want > >each of these characters to be displayed as discrete
glyphs.
> >
> >- Chris
>
>
>
>--------------------------------------------------------------
----
>Read K. Roberts
rroberts@adobe.com
>San Jose TW8 x64402 Weds, San Francisco (415)-586-1334 M, T,
Th, F
>--------------------------------------------------------------
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>
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