UCS Fonts

Introduction

The IYONIX pc is supplied with a new font manager which supports the ISO/IEC 10646-1:1993 Universal Character Set (UCS) specification. This allows more than 256 characters per font and this capability is typically used to extend the range of characters available, to provide access to special characters and also to support Japanese, Chinese and other languages.

Note that while the UCS character codes are identical to the Unicode character codes, the UCS specification differs from the Unicode one (the main difference being that the Unicode specification includes implementation details).

Compatibility

The UCS Font Manager is fully backwards compatible with older versions of the Font Manager and supports almost all existing API calls. The standard RISC OS font format is used.

It is not necessary to convert all applications to support UCS fonts and applications will work without any changes to the font system. However, UCS fonts are becoming increasingly important and many web pages make use of them. It is therefore important that RISC OS text processing applications are aware of UCS fonts. In particular, web browsers and applications that can import and export Word, HTML, RTF or PDF files should support UCS fonts.

Documentation

Documentation on the new font manager is provided in this Zip file:

fonts.zip

Latin Character Sets

The standard fonts (Homerton, Trinity and Corpus) now provide around 320 characters per font and they include all of the characters in the ISO 8859 Latin 1 through to Latin 9 alphabets. Latin 8 will be welcomed by some as it provides Gaelic and Welsh letters to cover all Celtic languages.

See ISO 8859 Alphabet Soup for an introduction to these alphabets.

Note that these fonts contain a sub-set of the full UCS character set which contains thousands of characters.

Euro Symbol

RISC OS 5 provides the Euro symbol at character &80 in most Latin fonts and it matches the style of the font (for example, in Trinity Italic it has serifs and is sloping).

The Euro symbol also exists in the Latin 9 character set as character &A4 instead of character &80 and again, this is styled to match the font.

In RISC OS 4 the font-styled Euro appeared at character &80, as expected, but the standard non-styled Euro symbol also appears as character &A4 in Latin 1 and other character sets in some fonts (but not in the system font). This is incorrect as it should only appear once in each character set and RISC OS 5 will therefore only provide the Euro symbol at character &80 (except in Latin 9 where it will only appear at &A4).

Finally, the standard Euro symbol is also available in the Sidney font at character &F0 independent of any font styling.

Note that this change from RISC OS 4 may affect some software and some existing files, but the change makes sense as it conforms with Adobe and Microsoft implementations.