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<title>GIMP 1.00 Preview Issue 18</title>
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<H4>
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
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<center><img alt="GIMP 1.00 Preview" src="./gx/ayers/title.gif"></center>
<center>
<H4>By Larry Ayers,
<a href="mailto:layers@vax2.rainis.net">layers@vax2.rainis.net</A></H4>
</center>
<hr>
<center><h3>Introduction</h3></center>
<p>Allow me to state up front that I'm not a computer graphics professional
(or even much of an amateur!) and I've never used any of the common commercial
tools such as Photoshop. Thus it's not too surprising that my efforts to use
version 0.54 of the Gimp, the GNU-licensed image-editing tool developed by
Spencer Kimball and Peter Matis, often were frustrating. But one day I
happened upon the developer's directory of the Gimp FTP site and saw there a
beta release, version 0.99.9. This sounded awfully close to version 1.00, so
I thought I'd give it a try.
<p>At first it absolutely refused to compile. After downloading this large
archive, I wasn't about to give up, and after several false starts I found
that if I compiled each subdirectory first, followed by installation of the various libs
and running <em>ldconfig</em> to let <i>ld.so</i> know about them, the main
Makefile in the top directory would compile without errors. The Motif libs
aren't needed with this release, as the new Gimp ToolKit (GTK) has been
implemented as a replacement.
<p>An analogy occurred to me as I gradually discovered how complicated and
powerful this application is. It's the XEmacs of image editors! The plug-ins
and scripts are like Emacs LISP extensions and modes, both in their
relationship with the parent application and in their origin: contributed by a
wordwide community of users and developers.
<p>This release does have a few problems. Occasionally it will crash, but politely;
i.e. it doesn't kill the X-server or freeze the system. The benefits of this
release far outweigh these occasional inconveniences, especially for a rank
beginner.
<center><h3>Structural Changes</h3></center>
<p>Image editing is a notorious consumer of memory. This new version has a
method of attempting to minimize memory usage called tile-based
memory management. This allows the Gimp to work with images larger than
can be held in physical memory. Disk space is heavily used instead, so make
sure you have plenty of swap!
<p>A new file format specific to the Gimp, (<i>*.xcf</i>), allows an image to
be saved with it's separate layers, channels, and tiles intact. In ordinary
image formats all such information disappears when the image is saved. This
would be ideal if an image had to be changed at a later date, allowing
effective resumption of an editing session.
<p>An extension is like a plug-in but is not called from or associated with a
specific image; the first of these is described in the next section.
<center><h3>Script Fu</h3></center>
<p>The Gimp now has a built-in scripting language, based on Scheme, which
bears some resemblance to LISP. An extension called Script Fu (which can be
started from the Gimp menubar) can read these scripts and perform a series of
image manipulations on user-specified text or images, using user-selected
fonts and colors. What this means for a beginner like myself is that a
complicated series of Gimp procedures (which would probably take me a day to
laboriously figure out) is now automated. A collection of these scripts is
installed along with the other Gimp files, and more are periodically released
by skilled Gimp users. Many of the scripts facilitate the creation of text
logos and titles suitable for use in web pages.
<p>Here is a screenshot of the Script Fu window:<br>
<p>
<img alt="Script Fu Window" src="./gx/ayers/scriptfu.gif">
<p>As you can see, entry-boxes are available for filling in. Most scripts
have default entries, and scripts will certainly fail if the default font is
not available on your system.
<p>This script-processing ability should greatly expand the popularity of the
Gimp. I showed Script-Fu to my teenage kids and they took to it like ducks
to water, whereas before they had been intimidated by the Gimp's complexity
and deeply nested menus. A little easy success can give enough impetus to
explore further.
<center><h3>Plug-Ins</h3></center>
<p>I believe that among the most important factors contributing to the
success and continuing development of the Gimp are the built-in "hooks"
allowing third-party plug-in modules to add capabilities to the program. The
GTK ends up doing all of the mundane tasks such as creating windows and their
components; all a plug-in needs to do is manipulate graphics data. One result
is that the plug-ins are surprisingly small considering what they can accomplish.
<p>One reason the release of Gimp version 1.00 has been delayed is that the
plug-ins which had been written for version 0.54 won't work with version 1.00
(or any of the recent betas). This was partly due to the switch from Motif to
the GTK, and partly to the new memory-management scheme. The plug-in
developers have been busily modifying their modules and the great majority
have been successfully ported. Since the release of 0.99.9 several
interesting new plug-ins have been released, including:<br>
<ul>
<li>IFSCompose, by Owen Taylor, is a utility for the interactive creation of
Iterated Function System fractals, which can then be included in an
image. See my review of Xlockmore in this issue for a brief description
of this fractal type.
<li>CML Explorer, by Shuji Narazaki, creates Coupled Map Lattice images;
these are models of complex systems' time-changes and the results can be
striking patterns. This is a complex plug-in with many parameters to
tweak. The best way to get an idea of what it can do is to download
parameter files from
<a href="http://www.inetq.or.jp/~narazaki/Products/gimp-plugin.html">this site</a>.
<li>Whirl and Pinch is a merging of two older plug-ins (you guessed it -- Whirl
and Pinch!). Federico Mena Quintera is the author, as well as being one
of the Gimp developers.
<li>FP, or FilterPack, is a useful utility for adjusting the color-balance
of an image in a variety of ways, with thumbnail images showing the
results of changes as you make them. It was written by Pavel
Greenfield; his page
<a href=http://www.geocities.com/SoHo/5277"">here</a> explains and
illustrates its usage.
</ul>
<p>As well as these and other new plug-ins, many of the old ones were enhanced
in the process of adapting them to the new release. Several now have
real-time preview windows, in which the results of changes can be seen without
committing them.
<center><h3>Tutorials</h3></center>
<p>The Gimp has never had much documentation included with the archive. This
will eventually be remedied; the Gimp Documentation Project, analogous to the
Linux Documentation Project, will be making documentation freely available.
Until the fruits of that project begin to appear there are some excellent
tutorials, written by various charitable Gimp users and developers and available
on the WWW. <a href="http://abattoir.cc.ndsu.nodak.edu/~nem/gimp/tuts/">
The Gimp Tutorials Collection</a> is a site which has links to many of the
tutorials out there. The tutorials situation is in flux at the moment, as
some are specific to Gimp 0.54 while others are intended for the newer betas.
<p>A site which has helped me get started is
<a href="http://lemming0.lem.uni-karlsruhe.de/~jens/">
Jens Lautenbacher's Home Page.</a> His tutorials are very lucid and easy to
follow, and are specific to version 0.99.9. This site is also an inspiring
example of how the Gimp can contribute to the design of a web-page.
<center><h3>News and Compendia</h3></center>
<p>If you'd like to keep up with the rapidly evolving Gimp scene, these links
are among the best I've found and can serve as starting points.<br>
<ul>
<li><a href="http://kiwi.cs.berkeley.edu/~gimp/">
Archived messages</a> from the three Gimp mailing lists; new plug-ins are
announced here and source patches are posted.
<li><a href="http://www.nuclecu.unam.mx/~federico/gimp/index.html">
Federico Mena Quintera's Gimp page</a> is full of links, tips, and news.
<li>The Gazette's own Michael J. Hammel has a series of
<a href="http://www.csn.net/~mjhammel/gimp/gimp.html">
Gimp pages</a>
containing information, tips and tutorials.
<li>Zachary Beane maintains this oft-updated Gimp
<a href="http://xach.dorknet.com/gimp/news/index.html">
news page</a>; there is
quite a bit of other good Gimp-related stuff at his site.
<li> And of course the<a href="http://www.XCF.Berkeley.EDU/~gimp/">
official Gimp home page!</a>
</ul>
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<P> <hr> <P>
<center><H5>Copyright © 1997, Larry Ayers<BR>
Published in Issue 18 of the Linux Gazette, June 1997</H5></center>
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