◄Up► ◄Next► ◄Previous►
────────────────────────────────────────────────────────────────────────────
 
The Microsoft Windows Printers and Fonts Kit explains how to create files
that support the installation and use of printer and screen fonts for
Windows-based drivers. This book is intended to be used by:
 
♦  Third-party font vendors who develop fonts for  Hewlett-Packard Printer
   Control Language (PCL), Adobe PostScript(R), and other printers.
 
♦  Cartridge manufacturers for printers that use PCL.
 
♦  Printer manufacturers who have printers that support downloadable fonts
   or cartridges, and who want to make the font installation of their
   respective drivers consistent with other drivers.
 
Printer and Screen Fonts
 
The advances in desktop publishing and other computer endeavors have led to
an increase in the variety and quality of fonts available for printers. At
the same time, the need for quality screen fonts has grown and users expect
a reasonable approximation on the screen of what they plan to print. Since
the fonts used to print a document are rarely the same as the fonts used to
display the document on the screen, font vendors must supply screen fonts
that complement their printer fonts and information files that accurately
define the metrics (size and shape) of the printer fonts. When a user
installs the screen fonts and the metrics files, Microsoft(R) Windows(TM)
application can take advantage of the fonts to generate the best possible
WYSIWYG (what you see is what you get) display.
 
Windows Font Requirements
 
To ensure Windows applications can generate the best possible output, the
Windows environment must ultimately receive the following items for each
font:
 
♦  The printer font, given as a printer-resident font, a downloadable font,
   or a cartridge.
 
♦  A screen-font file in Windows .FON file format. The font must provide a
   reasonable approximation of the printer font while matching the aspect
   ratio of the display device.
 
♦  A Printer Font Metrics (PFM) file or a Printer Cartridge Metrics (PCM)
   file suitable for the given Windows printer driver. The files must
   contain the metrics for the printer font, including font face, character
   widths, and pair- and track-kerning information.
 
The font vendor must make provisions to update the Windows initialization
file, WIN.INI, to make the display and printer drivers recognize these
fonts. Ideally, the printer driver will contain an installation program that
will read the font vendor's floppy disks, and install these files. In the
absence of such a utility, the font vendor should provide a user-friendly
installation program. Although Control Panel can install screen fonts,
installation of printer fonts and metrics files is too specific for each
device to allow for a generic installation program in Windows.
 
Downloadable Fonts
 
Downloadable fonts (also called soft fonts) are the most cost-effective way
to distribute additional fonts for a printer device. This approach enables
third-party vendors to create and distribute downloadable soft fonts for a
device. Downloadable fonts also enable users to access a larger variety of
fonts than could be held in their printer's memory. This is possible because
the driver selectively downloads the fonts only when needed.
 
Each downloadable font must have a font file in printer-specific format.
This file is in the printer's font-command language. For the Windows printer
driver to download the file, it must know where the file resides on the
user's hard drive. Many Windows printer drivers use softfont settings in the
WIN.INI file to determine the font file locations.
 
Bitmap Screen Fonts
 
Font vendors should create bitmap screen fonts to accompany their printer
fonts. Screen fonts should be created for the aspect ratios of each of the
popular display device classes. Minimally, a vendor should supply line sizes
that match the frequently used graphic arts point sizes (that is, 8, 9, 10,
12, 14, 18, and 24). Screen fonts are measured in line sizes
(lines-per-inch) rather than typographic point sizes. Specific line sizes of
the fonts may be different from their nominal point sizes.
 
Metrics Files
 
Downloadable and cartridge fonts need Printer Font Metrics (PFM) and Printer
Cartridge Metrics (PCM) files. These files contain the same kind of header
information as Windows screen-font files, but also include extended font
metrics, kerning tables, and driver-specific information. A Windows printer
driver uses the information in a metrics file to prepare the width and
kerning tables used by the application during composition. A font vendor
must provide PFM files for downloadable fonts and PCM files for cartridges.
 
Permanent and Temporary Downloadable Fonts
 
There are two forms of downloadable fonts:
 
♦  Permanent Soft Fonts. These are copied from the computer to the printer
   when the printer is first turned on, and remain there until the printer
   is turned off. The Windows printer driver has access to permanent soft
   fonts for all the documents that it prints.
 
♦  Temporary Soft Fonts. These are copied from the computer to the printer
   on an as-needed basis during the print job. They are deleted from the
   printer's memory at the end of a print job.
 
Settings in the WIN.INI file specify whether a downloadable font is
permanent or temporary. Furthermore, permanent fonts typically have a
corresponding batch file that copies the fonts to the printer when the
system first starts.
 
Downloadable and Cartridge-Font Installation
 
For the Windows printer driver to correctly locate downloadable or cartridge
fonts, the driver or a vendor-supplied utility must perform the following
operations:
 
♦  Install the PFM, screen font, and downloadable font files by copying them
   from the font manufacturer's floppy disks to the user's hard drive.
 
♦  Add the softfont or cartridge settings in the WIN.INI file.
 
Ideally, the softfont and cartridge settings in the WIN.INI file should be
set automatically by an installation program. Some Windows drivers, such as
the HP LaserJet printer driver that uses PCL, contain their own font
installation program. If the driver does not contain an installation
program, the font vendor should make every effort to provide an installation
program rather than direct the user to install the files manually.
 
 
                                      ♦