RISC World

A. More about Fonts

Ovation is supplied with the following fonts:
  • Paladin   (a Palatino ® eqivalent)
  • SwissB   (a Helvetica ® equivalent)
  • SymbolB   (a Symbol equivalent)
  • Vogue   (an Avant Garde ® equivalent)
Paladin, SwissB and Vogue are Latin character sets, each supplied in four styles: medium, medium italic, bold and bold italic. SymbolB contains Greek and mathematical characters and is supplied in a medium style only. The names in brackets above are the names by which these fonts are more generally known. They are also the names of the corresponding fonts built into most PostScript laser printers. If you print out a file using a PostScript printer, the PSprolog file in the !PrinterPS printer driver correctly maps the Ovation font names to those in the PostScript printer. It is therefore essential that the !PrinterPS printer driver supplied with Ovation is used when printing to a PostScript printer. Please note that this file also contains the mapping information for the Acorn outline fonts Corpus, Homerton, Selwyn and Trinity.

Adding more Fonts

Many other fonts are available from various suppliers. To add new fonts simply copy the new font directories into the !Fonts directory on your work disc or hard disc. On floppy disc systems you will be limited by the number of font files that will fit on a single floppy disc. The availability of disc space on hard disc systems allows virtually no limit to the number of new fonts that may be installed, but if the number of outline fonts (different styles counting as different fonts) present exceeds 45 you may experience problems with the Edit application. Edit (version 1.00) checks the contents of !Fonts when it starts up and if the critical number is exceeded, it crashes with the error message: 'Edit has suffered a fatal internal error (type=5) and must exit immediately'. If your collection of outline fonts exceeds 45, keep the 35 or so which you use most often in !Fonts and the remainder in another directory, temporarily copying them into !Fonts when they are needed.

Ovation expects fonts to be available in the four styles: medium, medium italic, bold and bold italic. Not all fonts are available in all four styles and sometimes styles are known by other names. The medium version of Paladin, for example, is known as Paladin Roman. Ovation handles these variations in two ways:

  1. If a style that does not exist is chosen, Ovation will search !Fonts to see if an equivalent face is available with a different name. If medium is chosen, Ovation looks also looks for Roman, Light, Regular and Book. If bold is chosen, Ovation also looks for Demi and Black. If italic is chosen, Ovation also looks for Oblique and Slant.
  2. If a style does not exist and no alternative can be found, Ovation uses the closest possible face that does exist. For example, if Greek.Bold.Italic doesn't exist but Greek.Bold does, Ovation will use that.
If a font is present in a style other than Medium, Book, Roman, Regular, Demi, Oblique or Slant, it will be listed on the Font menu without a dot between style and font name. Thus if in addition to the normal SwissB family you have a font called SwissB.Narrow it will appear on the Font menu as SwissB Narrow. SwissB Narrow will be regarded in every respect as though it were a separate font from SwissB. Thus, while SwissB Narrow is the currently selected font choosing Bold style will select SwissB.Narrow.Bold if it exists. If it does not exist, SwissB.Narrow.Medium will remain selected; SwissB.Bold will not be selected.

Setting the font cache

The Outline Font Manager always keeps the most recently used character definitions in an area of memory called the font cache. The bigger the font cache the faster will be Ovation's response, since there will be fewer occasions when the font manager must access the !Fonts directory on disc for font information. If there is only a very small font cache or no font cache at all, the Font Manager may have to access !Fonts for every character that is drawn on the screen, greatly increasing the time taken to put characters on the screen.

The size of the font cache can be set in two ways:

  1. Use the task manager to set the font cache in the task display window.
  2. Configure your computer using *CONFIGURE FontSize, which will set the power-on default.
The recommended font cache size for a 1 Mbyte system is 64 Kbyte, although this could be reduced to 48 Kbyte or 32 Kbyte if only a couple of fonts are to be used. On 2 Mbyte and 4 Mbyte systems a 128 Kbyte font cache is recommended, but for documents using a wide range of fonts in different sizes, a 256 Kbyte font cache would be preferable.

Configuration settings

A number of configuration settings held in the computer's CMOS RAM are used to control the quality of the displayed characters. For most users these settings can be ignored, since they are set to sensible defaults on power-up. The suggested settings for various configurations are shown below, followed by a description of each option. These values may be changed in the usual way using the *Configure command. 
    Available RAM   1Mb   1Mb   2Mb   2Mb   2Mb   4Mb   4Mb   4Mb
    Screen mode      12    20    12    20    23    12    20    23
    FontMax2         15    30    15    30     0    20    40     0
    FontMax3         30    60    30    60    60    40    80    80

FontMax1

This variable is used to control the mixed use of outline and bitmap font files supplied with earlier Archimedes systems and should be left at its default of 0.

FontMax2

This variable sets the maximum size (in pixels, not points) of anti-aliased characters. Anti-aliasing, the technique in which grey pixels are used to make curves and diagonal lines look smoother, greatly enhances the appearance of screen displays especially where the pixel resolution is limited, but it quadruples the size of the bitmaps in the font cache and slows the system down appreciably. To turn off anti-aliasing entirely, set FontMax2 to 0.

FontMax3

This variable sets the maximum size, in pixels, of characters that are stored in the font cache. If you use characters larger than this size, they are drawn directly to the screen (or the printer buffer) from the outline. This facility prevents large fonts used occasionally for headings from flushing other fonts out of the font cache. Unfortunately it slows down the drawing of these characters considerably.

FontMax4 and FontMax5

These variables control sub-pixel anti-aliasing in the horizontal and vertical directions respectively. They marginally improve the quality of the displayed characters, but at the expense of font cache and time. Normally they should be left at their default values of 0.

FontMax

This variable determines the maximum size to which the Font Manager may automatically increase the font cache if it should become full. As soon as any fonts can be discarded, the font cache will automatically return to its original size. By default this variable is set to 0 and therefore the font cache will not automatically increase in size.