elcome to the Graphics Muse! Why a « muse »? Well, except for the sisters aspect, the above definitions are pretty much the way I’d describe my own interest in computer graphics: it keeps me deep in thought and it is a daily source of inspiration.
|his column is dedicated to the use, creation, distribution, and discussion of computer graphics tools for Linux systems.
This month has been even more hectic than most. I finished the first pass of an article on the 1.0 release of the GIMP and submitted it to the Linux Journal editors. That will be out in the November Graphics issue. I’ll probably have to do some updates after I get back the marked-up version. I’m also working on the cover art for that issue, using the developer’s release (currently at 0.99.10) of the GIMP. I’ve also had quite of bit of regular work (the kind that pays the rent) since I’m getting very close to my code freeze date. This weekend I’ll be writing up documentation for it so I can give an introductory class to testers, other developers, Tech Pubs, Tech Support, and Marketing on Monday. I think I picked a bad time to start lifting weights again.
In this month’s column I’ll be covering …
Next month may not be much better. I don’t know exactly what I’ll be writing about, although I do have a wide list from which to choose. Mostly I’m looking forward to my trip to SIGGRAPH in August. Anyone else going? I should have plenty to talk about after that. I plan on going to at least two of the OpenGL courses being taught at the Conference. I haven’t completely decided which courses I’m going to take, however.
|Disclaimer: Before I get too far into this I should note that any of the news items I post in this section are just that – news. Either I happened to run across them via some mailing list I was on, via some Usenet newsgroup, or via email from someone. I’m not necessarily endorsing these products (some of which may be commercial), I’m just letting you know I’d heard about them in the past month.|
| BTTV is a device driver for Booktree Bt848 based frame grabber cards like the Hauppauge Win/TV pci, Miro PCTV, STB TV PCI, Diamond DTV2000, and AverMedia. Major new features in version 0.4.0 are rudimentary support for grabbing into user memory and for decoding VBI data like teletext, VPS, etc. in software.
The Motif application xtvscreen now has better support for selecting channels and also works in the dual visual modes (255+24 mil. colors) of Xi Graphics AcceleratedX 3.1 X server.
| This is an initial developer’s release of an (unoffical) port of OpenGL(tm) for java. Leo Chan’s original package has been ported to both WindowsNT/95 and to Linux. Several features have been added, the main one being OpenGl now draws into a Java Frame. What advantage does this provide? Well, you can now add menus to the OpenGL widget as well as receiving all normal events such as MouseMotion and Window events. You could very simply have a user rotate a OpenGL object by moving the mouse around in the Frame ( the demo for the next release will have this feature ).
You can grab it from the developers web page at http://www.magma.ca/~aking/java.
|WebMagick is a package which makes putting images on the Web as easy as magick. You want WebMagick if you:
After nine months of development, WebMagick is chock-full of features. WebMagick recurses through directory trees, building HTML pages, imagemap files, and client-side/server-side maps to allow the user to navigate through collections of thumbnail images (somewhat similar to xv’s Visual Schnauzer) and select the image to view with a mouse click. In fact, WebMagick supports xv’s thumbnail cache format so it can be used in conjunction with xv.
The primary focus of WebMagick is performance. Image thumbnails are reduced and composed into a single image to reduce client accesses, reducing server load and improving client performance. Everything is pre-computed. During operationi, WebMagick employs innovative caching and work-avoidance techniques to make successive executions much faster. WebMagick has been successfully executed on directory trees containing many tens of directories and thousands of images ranging from tiny icons to large JPEGs or PDF files.
Here is a small sampling of the image formats WebMagick supports:
WebMagick is written in PERL and requires the ImageMagick (3.8.4 or later) and PerlMagick (1.0.3 or later) packages as well as a recent version of PERL 5 (5.002 or later). Installation instructions are provided in the WebMagick distribution.
Obtain WebMagick from the WebMagick page at http://www.cyberramp.net/~bfriesen/webmagick/dist/. WebMagick can also be obtained from the ImageMagick distribution site at ftp://ftp.wizards.dupont.com/pub/ImageMagick/perl.
| EasternGraphics announces the public release of `opengl’ widget which allows windows with three-dimensional graphics output, produced by OpenGL to be integrated into Tk applications. The widget is available for Unix and MS-Windows platforms.
You can download the package from ftp://ftp.EasternGraphics.com/
| There is a free demo package for Linux. It’s roughly 36M tarred and compressed. A 9M demo’s file is also available for download. I had placed a notice about this package in the May’s Muse column, but I guess ELECTROGIG had missed that, so they sent me another announcement (I got the first one from comp.os.linux.announce). Anyway, one thing I didn’t mention in May was the price for the full Linux product: $99. This is the complete product, although I’m not sure if this includes any documentation or not (it doesn’t appear to). The Linux version does not come with any product support, however. You need a 2.0 Linux kernel to run GIG 3DGO.
I also gave a URL that takes you to an FTP site for downloading the demo. A slightly more informative page for downloading the demo and its associated files is at http://www.gig.nl/support/indexftp.html
| James Macnicol uploaded version 0.5b of his type1inst font installation utility to sunsite.unc.edu. If it’s not already there, it will end up in /pub/Linux/X11/xutils.
Type1inst is a small perl script which generates the « fonts.scale » file required by an X11 server to use any Type 1 PostScript fonts which exist in a particular directory. It gathers this informatiom from the font files themselves, a task which previously was done by hand. The script is also capable of generating the similar « Fontmap » file used by ghostscript. It can also generate sample sheets for the fonts.
Editor’s note: I highly recommend this little utility if you are intent on doing any graphics arts style work, such as with the GIMP.
| It seems the interface to png-0.96 is not binary compatible with png-0.89, so the major version of the shared library was bumped to libpng.so.2.0.96 (last version was libpng.so.1.0.89).
WHAT IS LIBGR?
These are configured to build ELF static and shared libraries. This collection (libgr2) is being maintained by Neal Becker
|…there is a site devoted to setting up Wacom tablets under XFree86? http://www.dorsai.org/~stasic/wacomx.htm The page’s maintainer, Edward, says:
Adam D. Moss has said he’s also gotten this to work and offered to help others who might need assistance getting things set up.
…there is rumored work being done on 3Dfx support for Linux? Tige writes:
…the MindsEye Developers mailing list has moved to email@example.com. unsubscribing can be done by sending a body of
to firstname.lastname@example.org and a body of
to email@example.com Other majordomo commands should be sent to firstname.lastname@example.org a body of `help’ gives an overview. Users who are subscribed to the old email@example.com adress do not need to unsubscribe. The list will be removed shortly afterwards. They will get this message twice: one from firstname.lastname@example.org and one from email@example.com. An HTML interface by using hypermail is under construction.
Q and A
Q: Forgive what might be a dumb question, but what exactly is meant by « overlays »?
A: Imagine a 24bpp image plane, that can be addressed by 24bpp visuals. Imagine an 8bpp plane in front of the 24bpp image plane, addressed by 8bpp visuals.
One or more of the 8bpp visuals, preferably the default visual, should offer a ‘transparent pixel’ index. When the 8bpp image plane is painted with the transparent pixel, you can see through to the 24bpp plane. You can call an arrangement like this, a 24bpp underlay, or refer to the 8bpp visuals as an overlay.
Strictly, we call this « multiple concurrent visuals with different color depths », but that’s rather a mouthful. Hence, in shorthand we refer to it as « 24+8 » or « overlays », with « 24+8 » as the preferred description.
From Jeremy Chatfield @ Xi Graphics, Inc.
| After last month’s 3D Modeller update, I received email from Mark Hamstra at Bentley Systems, Inc. Mark is the man responsible for the ports of Bentley’s MicroStation and Masterpiece products that are available for Linux. I’ve included his response below. The stuff in italics is what I had orginally written:
I wasn’t sure what a few of these formats were, so I wrote Mark back to ask about them. He informed me on the following (which were the ones I had asked specifically about):
I want to thank Mark for offering updated information so quickly. My information is only as good as what I can find or am fed, and it helps when vendors, developers or end users provide me with useful info like this. Many thanks Mark.
If you’ve used this product on MS platforms, feel free to drop me a line and let me know what you thought of it. I’m always out to support commercial ports of graphics-related products to Linux.
| I bought an Epson Stylus Color 500 printer back in December of last year so I could print in color. I had done some research into what printers would be best, based in part on reviews in online PC magazines and also on support available in the Ghostscript 4.03 package. The Epson Stylus Color 500 was rated very high by the reviews and I found a web page which provided information on how to configure Ghostscript for use with the printer. I bought the printer, got Ghostscript working in a very marginal way (that is to say, it printed straight text in black and white). But that’s as far as it went. I had gotten some minor printing in color done, but nothing very impressive and most of it was downright bad.
Earlier this month I was given the opportunity to work on the cover art for an issue of Linux Journal. A few trial runs were given the preliminary OK, but they were too small – the size of the image needed to be more than twice as big as the original I had created. Also, because the conversion of an image from the monitor’s display to printed paper is not a straightforward one (see the discussion on LPI/DPI elsewhere in this month’s column), it became apparent I needed to try printing my artwork to sample how it would really look on paper. I had to get my printer configuration working properly.
Well, it turned out to be easier than I thought. The hardest part is to get Ghostscript compiled properly. The first thing to do is to be sure to read the text files that accompany the source code. There are 3 files to read:
The first two are the ones that made the most difference to me. I didn’t really use the latter, but my solution isn’t very elegant. However, what it lacks in grace it makes up for in simplicity.
was modified to add
right after the equal sign. I also didn’t need support for any of the HP DeskJet (DEVICE_DEVS3 and DEVICE_DEVS4) or Bubble Jet (DEVICE_DEVS6) devices so I commented out those lines. Now, once this file had been linked to makefile I could just run
to find out if you have Ghostscript 4.03. You’ll need it to work with the Epson Stylus Color 500.
Now I needed to set up my print spooler. This turned out to be rather easy. First, you need to know that the stcolor driver (which is the name of the driver Ghostscript uses to talk to Epson Stylus printers) has a pre-built Postscript file that is used to prepare the printer for printing. This file, called stcolor.ps, is included with the 4.03 distribution. The file contains special commands that are interpreted by the printer; however, it does not actually cause anything to be printed.
The following links are just starting points for finding more information about computer graphics and multimedia in general for Linux systems. If you have some application specific information for me, I’ll add them to my other pages or you can contact the maintainer of some other web site. I’ll consider adding other general references here, but application or site specific information needs to go into one of the following general references and not listed here.
Linux Graphics mini-Howto
Unix Graphics Utilities
Linux Multimedia Page
Some of the mailing lists and newsgroups I keep an eye on, where I get alot of the information for this column:
The Gimp User and Gimp Developer Mailing Lists.
The IRTC-L discussion list
I have no idea. I have a ton of things that need doing, but I just haven’t had time to figure out what I *should* do. I still have part 3 of the BMRT series to do, which I plan on doing as part of the process of creating an animation. The animation is another topic I’d like to do. I’ve also had requests for a number of other topics. One good one was to cover the various Image Libraries that are available (libgr or its individual components, for example). I have a review of Image Alchemy to do (long ago promised and still not done *sigh*). Well, at least I’ll never be short a topic.
Let me know what you’d like to hear about!
Graphics Muse #1, November 1996
Graphics Muse #2, December 1996
Graphics Muse #3, January 1997
Graphics Muse #4, February 1997
Graphics Muse #5, March 1997
Graphics Muse #6, April 1997
Graphics Muse #7, May 1997
Graphics Muse #8, June1997