AmigaOS 4.0 - About OS4 - Commands
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The Amiga's Operating System only supports a character set of 256 characters, each allocated a system number from 0-255 (although some numbers are reserved for special printing/display-terminal functions like carriage return and line feed). The operating system associates a default, predefined character (or, 'glyph') to each displayable system number depending on the language being supported. (The glyphs for letters A-Z and a-z and the numerals 0-9 are allocated in the system number range of 48-112 along with some punctuation marks for operating systems intended to display this page.) The appearance, or font style, of the individual glyphs can be changed by selecting an alternative font style (e.g. 'Times'). However, some fonts do not have glyphs defined for all of the displayable operating system character numbers. Some programs support many more than 256 characters (glyphs) because they represent characters in document files by using the Unicode character set (an international standard with a potential of hundreds of thousands, even millions, of characters). In order for these programs to display the document characters on the screen, send them to a printer or create a PDF file, they have to translate from the Unicode number in the file to the appropriate system number for the operating system and language being used. This applies to both printable and non-printable characters such as names of variables, style tags, and element names. If a dialogue box is used to change, for example, a style tag, the programs have to translate the characters selected in the dialogue box (and therefore conforming to the operating system character set) into Unicode before inserting them as non-printable characters into the document file. The same is true of printable text typed into a program's text frames and boxes. BUILDMAPTABLE converts Charset-To-Unicode mapping tables in text form (e.g. available at http://www.unicode.org/Public/MAPPINGS/) to mapping tables in binary form usable by diskfont.library. You must specify a <Unicode mapping table> name when using the BUILDMAPTABLE command. BUILDMAPTABLE can either display a text form of the parsed table or create a binary mapping table in the L:Charsets/ directory. Currently only 8bit charset mapping tables are supported. If L:Charsets/character-sets or L:Charsets/custom-character-sets contains a MIME name for an 8bit charset where no mapping table in L:Charsets/ does exist, and you have a mapping table in text form, use BUILDMAPTABLE to create the binary mapping table and reboot (diskfont.library searches tables only once) to be able to use the new charset (e.g. in fonts or catalog files). The expected format of text mapping tables is as follows:
Example 1: Example 2:
Disclaimer: Amiga Auckland have prepared the above information for the use of its members based on our experiences and as such is subject to revision at any time. Amiga Auckland cannot guarantee any of the information and cannot be held accountable for any issues that may result from using it. |