At 10:56 PM 05/10/2004, you wrote:
XML character references like "Ω" allow for the representation of Unicode scalar values which are not supported by the character encoding scheme used to serialize an XML document. They are a sort of meta-serialization. The character reference "Ω" advises an XML processor to replace this reference with a representation of the Unicode scalar value 937 (which stands for the Greek upper-case Omega abstract character). This is equivalent to the XML character reference "Ω"
Are you saying that the entity "Ω", which is the Greek upper-case Omega abstract character in Unicode, is not the Greek upper-case Omega abstract character in UCS-4? In other words, that the 937 code point refers to different abstract characters in Unicode vs. UCS, that the two standards map the same code point to different characters? If so, it appears (to me, at least) to be a very bad design choice; conversion would certainly be needed in this case. If not, then UCS Ω is exactly the same as Unicode Ω, and no conversion of the entity coding is needed.
There must be a character chart somewhere comparing UCS and Unicode code points...
"Fonts" are again from a different level of abstraction. A font is a set of so-called "glyph images" used for the visualization of characters. A character may be represented by different glyph images, and the same glyph image might represent different characters.
Exactly. So if the font in use had no glyph at code point Ω, or had some other glyph there, you would not see the Greek upper-case Omega with that font. My badly-stated point was that while the entity Ω always means the Greek upper-case Omega abstract character in the Unicode standard, the glyph you actually see depends on the font in use. A Unicode-compliant font should show the Omega glyph, but whether it does or not is up to the font creator.
David
David Badke