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What is VisualOberon?
=====================
VisualOberon (or short 'VO') is a collection of classes written in
the programming language Oberon-2. The classes are designed to easily
build graphical user interfaces for programs written in Oberon-2. VO is
distributed under the GNU license and it uses OO2C as development tool.
Oberon-2 is an object-oriented programming language, a successor of
Pascal, designed by the renowned Niklaus Wirth. It combines the popular
and proven design of Pascal (strict type system, easy to read code,
easy to follow program flow, possibility to naturally structure your
source code) with the modularity of Modula-2 and enhances both of them
with clean, simple but powerful object-oriented concepts, including
inheritance, dynamic type information, virtual methods, various access
rules on class and module basis and a built-in garbage collector.
VisualOberon uses OOC and its first implementation OO2C as
development tool, but VisualOberon's design is not limited to that
compiler. It is based on the language defined by the official language
report and thus should be easily portable to other compilers.
What are its main design criteria?
==================================
Simplicity:
VO should provide a powerful layout tool for the programmer, but
should also eliminate the need to handle low-level GUI details. It
should also free from needing to make low-level design decisions.
In a way it is similar to TeX. You give it a abstract description
and it will generate a good-looking GUI by its own.
Extensibility and flexibility:
The classes should be designed to make them easily extensible.
Features missing should be easy to integrate without the need to
rewrite huge code sections and without breaking compability.
Portability:
The class library should be portable so that the classes share the
same interface among different platforms. Programs building an
interface under one operating system should be portable without
any changes to the code. The class library itself is not portable
because it is implemented by making specific OS-dependent calls.
VO must be adapted to each OS. However, VO tries to build a
abstraction layer everywhere where it is possible to hide
OS-dependent details.
Configurability:
Since VO should be platform independent it must be possible to get
a native look and feel. VO achieves this not by building a layer on
the existing API of the OS, but by building its own GUI objects
which are flexible enough that their look and feel can be easily
configured to mimic the look and feel of the current OS. While far
from being perfect, the current version demonstrates the potential
and proves the concept of a configurable GUI.
Modern features:
VO should give the programmer access to all common GUI features
like auto font adapting, resizability, and things like drag and
drop... It should be possible to build a complete state-of-the-art
GUI.
Free use:
VisualOberon is available under the GNU programming licence (GPL)
and thus guarantees free use.
Development style:
The incremental development methodology offers quick updates and
bug fixes, fast response to problems and good communication and
code exchange between developers and users.
What is the current status?
===========================
Many common object have already been implemented. Key features like
keyboard and focus handling and drag and drop have already been
implemented. VisualOberon has also been used as the development basis
for a number of programs which have shown the validity of the applied
concepts. The screenshots on our homepage should show that VisualOberon
is already beyond its planning phase and is well within its
implementation phase. Only a few common objects are still missing.
What is missing?
================
While the concept of VisualOberon has been proven, a lot of work
still remains. There are a number of objects missing. VisualOberon is
currently a project led by a few people and it is clear that their
combined efforts are not enough to make VisualOberon the
state-of-the-art GUI engine we know it could be.
Thus VisualOberon definitely needs the active support of more
people. This should of course mainly be programmers but also designers
and people with knowledge about various systems and concepts are
needed. We also need more demo programs and people using VisualOberon
in real world applications by writing programs. People writing
documentation are also welcome. In the end, support for hardware in the
form of mirrors and ftp access for the developers are a good things to
have :-)
You ask what you can get back for your investment in supporting
VisualOberon? First you can learn much about the design and the
implementation of a huge project. You learn much about the design of a
GUI system from the ground of. VisualOberon and it full published
source code lets you look behind the scenes of a modern,
object-oriented GUI. You learn much about cooperating and programming
in a team.
There are also direct advantages for your own programs. VisualOberon
due to its powerfull design:
* offers you an excellent platform for rapid protoyping.
* gives quick and safe development of even larger applications.
* multiplies the power and simplicity of Oberon-2.
* provides a powerful, object-oriented design.
* gives you maximum flexibility.
* offers you the best GUI-development tool in years.
* uses a portable core interface to the underlying OS.
* guarantees that your applications will run under a variety of
systems.
* has a built-in ability to fundamentally change the look of the GUI.
* guarantees your applications will adapt to the look and feel of
any host OS.
Addresses of mailing list, home page, ftp and address of the programmer:
========================================================================
The address of the home page is:
`http://ping.de/sites/edge/VisualOberon.html'.
The address for source code downloads is currently also:
`http://ping.de/sites/edge/VisualOberon.html'.
The address of the mailing list is:
<VisualOberon@edge.ping.de>.
Write to
<majordomo@edge.ping.de>
for information how to get on the VisualOberon mailing list.
Contact person:
Tim Teulings <rael@edge.ping.de>.
Information about Oberon-2
==========================
For a first overview over Oberon-2 look at
`http://www.ics.uci.edu/~oberon/intro.html'.
A huge number of additional information can be found at
`http://www.math.tau.ac.il/~laden/Ob-pkgs.html'. A european mirror will
soon be `http://shulen.Hagen.de/IF/Oberon/'.
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