Editor's Note: On April 5th we published an article titled
Dead? No Way!, by Antony Fountain, co-author of our newly released
book Volume 6B:
Motif Reference Manual, 2nd Edition. In the article, Antony argues
quite forcefully that Motif is not only very much alive, but is instrumental
to the development of large-scale Unix applications. On April 6th we received
the following email from Chris Wareham, a self-described "former Motif
programmer" who now develops with GTK+. Chris took exception to several of
Antony's points and we asked for permission to publish his letter. In the
spirit of fairness, we also invited Antony to respond. Their dialogue
Date: April 6 2000
From: Chris Wareham
Subject: Regarding the "Is Motif Dead?" article
As a former Motif programmer I read your current article asking whether
Motif is "dead" with some interest. While it was obviously tied in with
the release of an updated Motif reference book, the article focused on
perceived shortcomings in more popular toolkits like Qt and GTK+. I cannot
speak for Qt, as I am not a keen C++ programmer, but I now do all my GUI
programming using GTK+. I consequently found the comments about GTK+ a
little bit partisan and very inaccurate.
Firstly, Antony Fountain points out that GTK+ and Qt are easier to program
in than Motif. This is Motif's biggest weakness. Regardless of whether it
is better looking or more fully featured than the new toolkits, Motif
falls down because development times are so much longer. It is all too easy
to make subtle errors when instantiating Motif widgets, as type checking
of widget attributes is virtually non-existent.
As for whether Motif is better looking than its younger competitors, that
is a very subjective thing. However, to argue that Motif is simply more
consistent because of its design guide is misleading. The style guide is
out of date, and rarely read by the Motif developers I worked with. The
richer palette of widgets that comes with GTK+ and the Gnome libraries
enforces a consistent look and feel much more effectively than a largely
ignored style guide.
Fountain then claims there is good commercial support for Motif. That's
patently untrue, as the few companies who offered GUI builders or custom
widget libraries have been reduced to a handful of consultancies. These
small, specialised companies do not make a viable support base.
There are certainly no commercial GUI builders for GTK+, but there are
several free ones--including the superb Glade, which eclipses any GUI
builder I saw for Motif. There are also a choice of IDE's for Qt and
GTK+, most notably Kdevelop, which again surpasses anything offered for
Next, Fountain plays up Motif's tight integration with Xt. This is a
two edged blade, as once wedded to Xt's convenience routines it is very
hard to port an application from it. This has hindered the popularity of
NEdit (the notable programmers' text editor), which would require a
total rewrite to make it portable.
As for internationalisation in Motif (which it inherits from Xt), it is
very outdated and tedious to work with. It is also a little disingenuous
to describe GTK+ as lacking in internationalisation features. It has GNU
gettext support, which is far more elegant than Xt's internationalisation.
There is also a near complete implementation of
Pango which brings
support for languages and character sets way beyond the scope of Xt. The
admittedly poor GTK+ text widget has a number of replacements on the way;
it is simply a case of the GTK+ developers settling for the best one
before 1.4 is released.
In conclusion, Motif isn't dead. It is simply awaiting its pension before
disappearing into retirement. Development on Motif has ground to a halt,
while that of GTK+ and Qt continues at a breakneck pace. The only
rational reason to stick with Motif is for that stability of the API--as
long as you can live with it's "designed by committee" complexity,
lack of features and pitiful commercial support.
P.S. How about teaming up with RedHat software to produce the definitive
GTK+ books (volumes 9A and 9B of the X Window series perhaps?).
From: Antony Fountain
Date: April 11, 2000
Subject: The Author Responds
Development time using a good GUI builder ought to be similar for all
languages, and generate code such that the cited issues are redundant.
Motif 2.x is worked out much better for C++ in any case. If you must
hand write code, expect longer development times and increased bug rates.
The view of the application becomes more abstract in a GUI builder, and
more can be held in the programmer's head. Millions of lines of code
simply demands automatic support.
I cited the GTK+/Qt style guides issue as evidence of a community symptom,
not as proof of internal Motif consistency. The Motif Style Guide most
certainly is read, but it is a guide, not a Bible. Some of the
data are rules, others are hints, and time admittedly has rendered other
points as out of date as GUI design moves on. Experience is the key:
I would urge anyone developing interfaces to read the book or similar
at least once for a general grasp of application GUI design. The interface
is how the user interacts with a program; it makes or breaks the product
irrespective of the algorithms behind.
I hotly dispute that GTK+ is "richer." I have integrated over 650
Motif-compatible components into X-Designer, from small components through
to integrated MVC table/graph/chart systems. MVC components are absolutely
essential for the very large-scale data manipulation and presentation in
certain application domains. Where is the Linux toolkit equivalent of these?
As for commercial support, Sun Microsystems, Silicon Graphics, Hewlett
Packard and all the other major UNIX operating system vendors continue
to support Motif. The add-on components and GUI builders for Motif are
fully mature. Commercial applications take years to develop because they
have thousands of screens and millions of widgets: they must use a GUI
builder capable of handling the connections between very large system
modules. And because projects have a development cycle of years, there must
be guaranteed on-line support for the duration. Although there are indeed
some private GUI builders available for GTK+, this is no guarantee of
continuance. The winner of the current LinuxWorld Editor's Choice Award
for GUI builder is X-Designer, not Glade.
As for Xt and portability, I strongly recommend using the native GUI
toolkit for porting. An emulation never quite succeeds in providing the
full proper look and feel at all levels of detail, nor does it provide
consistent bug compatibility. There's far more to porting than just
running on the box That means, for Windows, use MFC. Using an X port or
emulator for Windows is simply wrong in principle. By the same measure,
so is using the "portability" of Qt or GTK+.
For cross-platform interface portability, the Java VM has become the de
facto alternative native toolkit supported by major operating system
vendors. However, Java can have serious performance issues associated
with the interface: a compiled/interpreted language is not as fast as
native machine code. Often Java is used on the server, with the client
interface in the native toolkit: Motif or MFC. The correct porting model
is Motif to Java, not Motif to GTK+ or Qt.
About internationalisation, I can name some Fortune 500 companies where
GNU is explicitly banned because of the legal ramifications of the
licenses. For commercial software, intellectual property rights are
everything. Secondly, I did not say that GTK+ was
internationalization-free; I said its support is non-standard and
incomplete compared to Motif. There is much more to internationalisation
than gettext/string and font support.
Finally, all software has a lifespan. Of course Motif will die eventually,
as will GTK+ and Qt. The fundamental issues are: how do we get there
from here? And once there, how do we keep from painting ourselves into a
black hole if we need to bail out? My contention is that in the absence
of either a complete component model or a cross-platform GUI builder for
GTK+/Qt, there is no way to automatically migrate via Qt or GTK+ at
either end. There are millions upon millions of lines of Motif out there,
and the Linux toolkits do not even attempt to address this issue.
Developers can go from Motif to Java or MFC using X-Designer and other
X/Motif GUI builders automatically because the component model built into
Xt enables construction of a code-free view of the application.
As for the future of Motif development? Watch this space.
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