This might be worth writing a Technical Note to start with; see http://www.unicode.org/notes/
Mark ________ [EMAIL PROTECTED] IBM, MS 50-2/B11, 5600 Cottle Rd, SJ CA 95193 (408) 256-3148 fax: (408) 256-0799 ----- Original Message ----- From: "Frank da Cruz" <[EMAIL PROTECTED]> To: "Pim Blokland" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Thursday, March 13, 2003 08:53 Subject: Re: geometric shapes > > I've got a few questions about the use of geometric shapes, like > > squares and such. > > Some of these look very similar to one another, and I don't know > > which ones to use in which circumstances! > > Are their any guidelines on their use? > > Just as an example, let's look at the squares. These come in four > > sizes: small, medium, medium small and (not specified). So my > > question is, as a writer: which one of these should I use when > > exactly? And as a font designer: what should they look like? Is a > > medium square (U+25FB) bigger or smaller than a square (U+25A1)? Are > > there any guidelines on how they should be positioned vertically, > > relative to normal text? Etc. > > The same goes for other shapes, of course. For instance, what > > criteria exist for, when creating a text, choosing between U+25B6, > > U+25B8 and U+25BA? > > Are there URLs available shich discuss these issues? > > > Block characters, as well as box- and line-drawing characters in general, > are mainly inherited from character sets in which they were included for > the purpose of character-cell graphics (e.g. on terminal screens, > text-mode DOS applications, etc), and their use makes sense only in a > monospace font. > > To my knowledge, the semantics of most of these characters is not described > anywhere, which leaves them open to misinterpretation, especially by font > designers who are not aware (e.g.) that such-and-such a line must extend to > the edges of cell, so it can join up with copies of itself in adjacent cells > to form an unbroken line. Or that the two lines of "lower left box corner" > must touch and bisect the top and right edges of the cell. And so on. > > In part this is explained by the fact that the original character sets from > which these characters were inherited were themselves documented only by > tables showing the glyphs, never by a description of how the glyphs were to > be used, or line up. Only experimentation with an actual terminal > (e.g. VT220) or PC code page (e.g. CP437) can reveal such things. > > The same concerns apply to some of the math characters -- integral and > summation sign pieces, etc, but then the character's purpose more obvious, > if not from its appearance, then from its name. > > For a bit more on this topic, see the "Supplemental Terminal Graphics for > Unicode" writeup: > > ftp://kermit.columbia.edu/kermit/ucsterminal/ucsterminal.txt > > for Unicode 3.2: > > http://www.unicode.org/reports/tr28/index.html > > - Frank > >
