On 09/26/2002 02:54:55 PM "chuck clemens" wrote:
>It appears as I mentioned in email to >Mark that Unicode fonts use block ranges. Can someone verify this? The TrueType font format allows a vendor to indicate which "Unicode ranges" a font supports. In Windows, there are APIs and data structures for making this information available to an app. The only problem is that the notion of "supports" is undefined: by what criteria does one decide whether a font "supports" a given range? Only if every character in that range is supported? Even if only one character in that range is supported? If >50% of the characters are supported? If all the characters from that range needed by some major language is supported? (If so, what major language, and how does one decide exactly what characters a language "needs"? Does English need the em dash? That depends upon one's purposes.) For details on Unicode ranges in TrueType fonts, see http://www.microsoft.com/typography/otspec/os2.htm#ur. Note, BTW, that these are not used on the Mac (I don't know about other platforms). Also, there's a real possibility that the number of Unicode ranges that may eventually need to be supported by this mechanism in TrueType fonts will exceed the number of ranges that the format can accommodate (it's a bit vector of 128 bits, and 83 have been assigned values to cover up to Unicode 3.0). - Peter --------------------------------------------------------------------------- Peter Constable Non-Roman Script Initiative, SIL International 7500 W. Camp Wisdom Rd., Dallas, TX 75236, USA Tel: +1 972 708 7485 E-mail: <[EMAIL PROTECTED]>
