William Overington <WOverington at ngo dot globalnet dot co dot uk> wrote:
> My point in citing The Respectfully Experiment in the recent post is > that even though the reasons for not including any more ligatures in > Unicode may have seemed totally reasonable at the time that that > decision was made, the idea of James Kass that the glyphs for > ligatures in an OpenType font could also be accessed directly does > add new evidence to the situation. In the light of this new evidence, > I am wondering whether the decision not to encode any new ligatures > in regular Unicode could possibly be looked at again. So the "new evidence" is that a precomposed glyph can be used both (a) directly, to render a single Unicode code point, and (b) indirectly, to render a combining sequence? There's nothing new there, William. Font designers regularly include a glyph for U+FB01 LATIN SMALL LIGATURE FI. It has always been known, and obvious, that a user could access this glyph directly by encoding U+FB01. With the advent of OpenType and a smart-enough rendering system, the user could alternatively encode the sequence U+0066 U+200D U+0069 (f ZWJ i) and get the same glyph. (Or, as John Jenkins points out, if you have a Mac you can see this glyph simply by encoding "fi," without the need for the ZWJ hint.) This isn't limited to ligatures, either. Font designers also regularly include a glyph for U+00E1 LATIN SMALL LETTER A WITH ACUTE. You can either encode U+00E1 directly and see the glyph, or you can encode U+0061 U+0301 (a �) and get the same glyph. This doesn't even require OpenType, just non-spacing glyphs. What is so different about doing this with a ct ligature, encoded provisionally in the PUA, compared to doing it with the fi ligature or the a-with-acute that have been in Unicode at least since version 1.1? Where is the new scientific discovery? > My intended meaning was that both types of ligation (precomposed and > ZWJ) could be in the same font. Of course they can. > Also, it is not a matter of overturning a decision, it is a matter of > the decision being modified in the light of the new evidence, namely > that both methods may be used simultaneously in an OpenType font. Without worrying about the distinction between "overturning" and "modifying" a decision, the fact remains that there is nothing new about this "new evidence." Every OpenType font designer knows it. -Doug Ewell Fullerton, California
