- OpenStep is an Application Programming Interface
(API) for creating
applications using the Objective C language. It was
published by
NeXT Computer Inc. in 1994.
OpenStep consists of three parts: the `FoundationKit',
a library of
non-graphical objects; the `AppKit', a library of
objects usful in
creating graphical applications; and `Display
Postscript', an
interface for drawing to the screen using the
PostScript graphics
language.
You can obtain a copy of the OpenStep standard from
the GNUstep web
site http://www.gnustep.org or it's mirror sites.
- Explain the organization of the front- and back-ends
The GNUstep GUI Library is divided into a front- and
back-end. The
front-end contains the majority of implementation, but
leaves out
the low-level drawing and event code. A back-end
can override
whatever methods necessary in order to implement
low-level drawing
event receiving. Different back-ends will make GNUstep
available on
various platforms. The default GNU back-end will run on
top of X
Windows and the DisplayGhostScript Server. Other
back-ends could
allow GNUstep to run on OpenGL, OS/2, and WIN32
graphics/event
platforms. Much work will be saved by this clean
separation between
front- and back-end, because it allows different
platforms to share
the large amount of front-end code.
- What is the current state of development of the X/DPS
back-end?
It works, but is slow and buggy. A lot of work could be
done.
GNUstep DisplayGhostScript Server
- What is the Display Ghostscript Server?
It is a free implementation of a Display PostScript
server based on
the ghostscript program by Aladdin software.
- What is its current state of development?
GNU contracted with Aladdin software to add some key
features to
ghostscript so it could be used as a DPS server. This
work has
mostly been done, althought Aladdin did not completely
finish the
work that they were contracted for. DGS works fairly
well with a
single context and will soon work with multiple
contexts. Alpha
channel and compositing currently doesn't work, but
should before
the end of 2000 (It's already been fixed in Ghostscript,
just not
released).
- What is the relationship between the Display
Ghostscript Server and X
Windows?
Display Ghostscript runs on top of X Windows.
All trademarks mentioned on in this FAQ belong to their
owners.
-- from GNUstep Frequently Asked Questions with
Answers (Last updated 2 August 2000 Please send corrections
to gnustep-maintainer@gnu.org.)