Specifications
OpenVMS VAX Operating System, Version 5.5-2 SPD 25.01.37
• Resource manager routines for loading user inter-
face definition files and creating widgets and gadgets
based on the contents of the definition files
The XUI Toolkit is used in conjunction with the DECwin-
dows User Interface Language (UIL) compiler. The user
interface definition files produced by this compiler con-
tain the data to separate form and function in DECwin-
dows applications and allow DECwindows toolkit wid-
get and gadget details, such as menu item labels, to be
stored separately from the toolkit and application run-
time code. This capability allows application developers
to prototype and modify user interface designs, separate
form and function in applications, and support interna-
tional products.
Enhanced X Windows Display PostScript (XDPS)
The Display PostScript system provided with VMS
DECwindows extends the native X graphical program-
ming environment for Digital DECwindows workstation
users.
X Display PostScript adds the following capabilities to
the basic X11 environment:
• All DECwindows fonts can be displayed at any size
and rotation angle
• XDPS graphics specified in a user-defined coordi-
nate systems are independent of monitor density
• Color or gray-scale rendition are automatically mod-
ified to take advantage of the monitor type through
either direct display, color dithering, or half-toning
• DPS Display routines can be downloaded to the
server and executed on command
• Sophisticated graphics primitives such as precisely-
controlled Bezier curves can be displayed
• Any display can be scaled and rotated arbitrarily
Programming access to XDPS is through the Adobe
Client Library. In addition, a converter called pswrap al-
lows users to convert PostScript code into C programs
that can be called from other languages.
Compound Document Architecture (CDA) Programming
Support
The CDA Toolkit provides access routines that applica-
tions can use to create, read, and write files contain-
ing compound text, graphics, and imaging data. These
files provide a vehicle for recording this information on
disk, a medium for interchange of this data between
applications, and an intermediate form from which high-
resolution printable graphics data can be generated.
In addition to providing support for developing new ap-
plications to access compound documents, VMS also
provides fallback support, allowing many existing utili-
ties to read and operate on these new kinds of files.
Transport Mechanisms
VMS DECwindows supports three different user-
selectable mechanisms for transport of X network pro-
tocol packets between applications and display servers.
A VMS DECwindows-specific shared memory-based
transport is used when the DECwindows application and
display server are located on the same workstation.
This optimization provides significantly greater perfor-
mance. It is the default transport under these circum-
stances.
DECnet is used when the DECwindows application and
display server are distributed across two different ma-
chines in the network. It is the default transport under
these circumstances.
TCP/IP is used when the DECwindows application and
display server are distributed across two different ma-
chines in the network and the Digital-supplied VMS
/ULTRIX Connection (UCX) layered product is being
used to make the connection. See the SOFTWARE
LICENSING section of this SPD for licensing details.
Workstation Device Support
The VMS DECwindows environment provides several
software components to support displaying graphics and
windowing output on and receiving keyboard and pointer
driver input from VAX workstations.
Device drivers are provided to support output to
monochrome and color displays and to receive input
from keyboard, mouse, and tablet devices.
A display server compatible with the X Window System
receives output requests from applications and trans-
lates those requests into driver commands. They also
relay driver-generated input events back to the applica-
tions.
Over 400 video fonts are provided in a variety of styles
and point sizes for use on 75 and 100 dot per inch (dpi)
monitors. These video fonts have been designed to cor-
respond directly to the fonts used by Digital’s PostScript
printers. In addition, a font compiler is provided so that
customers can make their own private fonts available
on their DECwindows workstations and terminals.
Multi-headed Workstation Support
A multi-headed workstation consists of one system box,
one keyboard and one mouse, but more than one mon-
itor and graphics controller. It is a single-user work-
station. Multi-headed workstations provide more screen
area for complex applications.
12