Chapter 7. AIXwindows Font Enhancements

ISO9241 Compliant Bitmap Fonts

The ISO standard 9241 "Ergonomic Requirements for Office Work with Visual Display Terminals (VDTs)", which provides minimum safety and health requirements for work with display screen equipment, was adopted by the Council of European Communities. These requirements for VDTs include the following bitmap font specific items:

• Character height
• Stroke width
• Character width-to-height ratio
• Character format
• Character size uniformity
• Between-character spacing
• Between-word spacing
• Between-line spacing
• Luminance contrast of character details, within or between characters.

The ISO9241-compliant bitmap fonts that are currently available include Ergo character cell fonts: Serif, Sans Serif, and Symbol proportional fonts; and Typewriter monospaced fonts. Since different monitors have different specifications, not all of these fonts will be ISO compliant on all monitors. However, clients can be configured with any font using available customizing tools.

TrueType Rasterizer

A TrueType rasterizer is available in the AIXwindows environment on AIX 4.3. The TrueType rasterizer supports TrueType 1.0 Font Files. Also, a TrueType font is available on AIXwindows 4.3 which supports most of the character sets currently defined in the Unicode 2.0 specification.

The font directory /usr/lib/X11/fonts/TrueType is in the default font path for the AIXwindows X-Server and the AIXwindows Font Server. Users prefering to off-load the rasterization from the X-Server should add an AIXwindows Font Server to the font path of their X-Server.

Font Encodings Supported by the TrueType Rasterizer

The AIXwindows TrueType rasterizer supports the font encodings required by the locales supported on AIX 4.3. The following tables describes the parameters used when generating a country-specific encoded bitmap font from a Unicode encoded TrueType font:

Note: This table is shipped in /usr/lpp/X11/defaults/TrueType/Xlfdcset. Users may extend the set of encodings supported by the TrueType rasterizer by making additions to this table.