ID Number: Q75742
3.10
WINDOWS
Summary:
Microsoft will strive to preserve compatibility of Windows 3.0 display
drivers with future versions of Windows. However, there are some basic
guidelines that must be followed to ensure full compatibility.
More Information:
To ensure full compatibility between Windows 3.0 display drivers and
future versions of Windows, adhere to the following guidelines
regarding fonts and the use of VDDs and grabbers.
Display drivers should use glyph caching, instead of caching the
entire character set. Display drivers that perform font caching may
encounter conflicts with the upcoming TrueType font technology. The
Windows 3.0 8514/a driver source code is a good sample of a driver
that uses glyph caching. Additional information will be available in a
future Windows device development kit (DDK).
Always use grabbers and VDDs from the same Windows version. Windows
3.0 VDDs and grabbers may not be compatible with their counterpart
components from future versions of Windows. For example, do not run
Windows 3.0 grabbers with Windows 3.x VDDs. Likewise, do not run
Windows 3.0 VDDs with Windows 3.x grabbers.
Furthermore, a third-party device driver designed to work with a
grabber or VDD from Windows 3.0 may not be compatible with the same
grabber or VDD from future versions of Windows. For example, a grabber
designed to work with the standard VGA VDD included in Windows 3.0
(*VDDVGA) may not be compatible with the standard VGA VDD included in
Windows 3.x.
Third-party display-driver OEM setup disks should include all
appropriate VDD and grabber files (regardless of whether or not the
files are included on the Windows 3.0 setup disks), and should not
require any changes. Unfortunately, some vendors do not ship VDD and
grabber files that are already available on the Windows 3.0 setup
disks.
Driver installation disks that provide a proprietary VDD, but rely on
standard Windows 3.0 installation disks for a grabber, should be
rebuilt to included the necessary grabber to ensure compatibility with
future versions of Windows.
Likewise, driver installation disks that provide a proprietary grabber,
but rely on standard Windows 3.0 disks for a VDD, should be rebuilt to
include the necessary Windows 3.0 VDD in order to ensure compatibility
with future versions of Windows.