flightgear/Thanks

A very special thanks is due to the following people and groups.

Note: as hard as we've tried, it is impossible to perfectly maintain
this file.  If you are aware of someone who you think should be
included here, PLEASE let me know.  Projects like this are made
possible only by the help and hard work of others.  I want to properly
credit everyone who has contributed to this project.


A1 Free Sounds <techie@mail.ev1.net> http://www.a1freesoundeffects.com
  Granted permission for the flightgear project to use some of the
  sound effects from their site.


Syd Adams:
  Added clipping to 2d instruments.  Added volume control to ATC-chatter.
  Created and maintain: DHC2, B1900D, Aerostar 700, S76C+ helicopter,
  Cessna Citation Bravo & CitationX, A6M2 'Zero'.  Assisted with Cessna
  Citation II with Curt and 777-200 with Justin Smithies.


Mark Akermann <flightgear@akermann.org>
  Redone sun code. The sun now consists of three textures with individual 
  colors which are calculated based on the effect of light scattering.
  This is accomplished by using various environmental data and by 
  calculating the distance the light travels through the atmosphere.


Raul Alonzo <amil@las.es>
  Mr. Alonzo is the author of Ssystem and provided his kind permission 
  for using the moon texture. I also used parts of his code as a template
  when adding the texture.  Ssystem Homepage can be found at:
  http://www1.las.es/~amil/ssystem


Michele America <nomimarketing@mail.telepac.pt>
  Contributed to the HUD code.


Andrei Barbu "T"Eval" teval@myrealbox.com
  Designed and implemented the current version of the FlightGear website.


Michael Basler <pmb@knUUt.de>
  Author of the Getting Started guide.


Paul Beardsley <Beardspa@hotmail.com>
  The 1903 Wright Flyer was inspired by a model contributed by Paul
  Beardsley.  Very little of the original model remains, but without
  Paul's excellent work we might not have our own 1903 Flyer. Model
  was reworked and retextured by Jim Wilson.


Jon S. Berndt <jon@jsbsim.org>
  Chief architect of JSBSim, the default flight dynamics model (FDM)
  for FlightGear. Jon's professional work has involved simulation and
  prototyping for vehicles ranging from the F-16 to his current work
  on the space shuttle and future manned launch vehicles. Since 1998
  Jon has been working on creating JSBSim together with co-author Tony
  Peden. JSBSim is an object-oriented, multi-platform aerospace
  vehicle simulator that can be integrated with broader flight
  simulation programs (since it provides no visual model), or run in a
  standalone mode for batch runs. For more information, see the JSBSim
  home page at:  http://www.jsbsim.org


Paul Bleisch <pbleisch@acm.org>
  Paul redid the "debug" system so that it would be much more flexible,
  so it could be easily disabled for production system, and so that 
  messages for certain subsystems could be selectively enabled.
  Also contributed a first stab at a config file/command line parsing
  system.


Jim Brennan <jj@kingmont.com>
  Provided a big chunk of online space to store USA scenery for Flight Gear.


Bernie Bright <bbright@bigpond.net.au>
  Many C++ style, usage, and implementation improvements.
  STL portability, tons o' stuff. :-)
  Threading support and threaded tile pager.


Bernhard H. Buckel <buckel@mail.uni-wuerzburg.de>
  Contributed the README.Linux
  Co-Author of the "Getting Started Manual"


Gene Buckle <geneb@deltasoft.com>
  Gene has done a lot of work getting FG to compile with the MSVC++
  compiler.  Also, he has pushed, proded, and bugged me endlessly to
  do my stuff right.  (I mean that in a good way, because sometimes
  when the little nudge in the right direction isn't working, I need
  a good hard shove.) :-)


Ralph Carmichael <ralph@pdas.com>
  Thanks to Ralph for his support of the FlightGear project. At
  Public Domain Aeronautical Software you will find the PDAS CD-ROM for sale,
  packed with great programs of use to aeronautical engineers. At this web
  site there are also some sample downloads to show what is on the CD.
  http://www.pdas.com


Didier Chauveau <chauveau@math.univ-mlv.fr>
  Provided some initial code to parse the 30 arcsec DEM files found at:
  http://edcwww.cr.usgs.gov/landdaac/gtopo30/gtopo30.html


John Check <j4strngs@rockfish.net>
  Maintains the base package repository
  Joystick howto
  Panel howto
  New instrument panel configurations


Dave Cornish <dmc@halcyon.com>
  Created our new, super cool, runway textures.
  Created some of our cloud textures.


Oliver Delise <delise@mail.isis.de>
  FAQ Maintainer, Documentation, Public Relations.
  Author of (the now depreciated) networking / multi-user support.
  Founder of the FlightGear MultiPilot Project :
  http://www.isis.de/members/~odelise/progs/flightgear


Dave Eberly <eberly@magic-software.com>
  Contributed some sphere interpolation code used by Christian Mayer's
  weather data base system.  Go to Dave's web site.  He has a ton of
  really useful looking code available there.
  http://www.magic-software.com


Olaf Flebbe
  Improved the build system for Windows and provided pre-built
  dependencies.


Jean-Francois Doue
  Vector 2D, 3D, 4D and Matrix 3D and 4D inlined C++ classes.  (Based on
  Graphics Gems IV ed. Paul S. Heckbert)
  http://www.animats.com/simpleppp/ftp/public_html/topics/developers.html


Francine Evans <evans@cs.sunysb.edu>
  Wrote the @#$@#$@% GPL'd tri-striper we use and "love". :-)
  http://www.cs.sunysb.edu/~evans/stripe.html


Oscar Everitt <bigoc@premier.net>
  Created single engine piston engine sounds as part of an F4U package
  for FS98.  They are pretty cool and Oscar was happy to contribute
  them to our little project.


Leidson Campos A. Ferreira <leidson@planetamessenger.org>
  Rewrote the Jpeg screen httpd streaming (--jpg-httpd option)


Bruce Finney <bfinney@gte.net>
  MSVC5 compatibility.


Melchior Franz <mfranz@aon.at>
  Reworked the joystick driver detection code, added high/low support for
  "hats".  Nasal-ified the Saitek Cyborg Gold 3D (USB) joystick which now
  forms the basis of a lot of programmable joysticks.
  Ruthlessly hunted down memory leaks in FlightGear, SimGear, and JSBSim.
  Maintains the only fully working helicopter model in FlightGear (Bolkow 105).
  Made the GUI code fully XML configurable and added support for themes,
  reworked property browser, route manager and several other dialogs.
  Wrote Dynamic Cockpit View, Fly-By view and lots of other Nasal code.
  Implemented Nasal "listeners".


Jean-loup Gailly and Mark Adler <zlib@gzip.org>
  Authors of the zlib library.  Used for on-the-fly compression and
  decompression routines.
  http://www.cdrom.com/pub/infozip/zlib/


Thomas Gellekum <tg@ihf.rwth-aachen.de>
  Changes and updates for compiling on FreeBSD


Neetha Girish <neethagirish@usa.net>
  Contributed the xml configurable HUD changes.


Jeff Goeke-Smith <jgoeke@voyager.net>
  Contributed our first autopilot.  (Heading Hold)
  Better autoconf check for external timezone/daylight variables in 
  #include <time.h>


Michael I. Gold <gold@puck.asd.sgi.com>
  Patiently answered my endless "newbie" OpenGL questions.
  His effort alone has made me a great SGI fan.


Habibie <habibie@MailandNews.com>
  RedHat package building changes for SimGear.


Dave Haskell <dave@haskell.demon.co.uk>
  Original exterior textures for the Cessna 310 U-3A model. Only a few
  minor modifications were made.


Mike Hill <mikehill@flightsim.com>
  Contributed 3d aircraft models to our project.
  http://www.flightsimnetwork.com/mikehill/home.htm


Erik Hofman <erik@ehofman.com>
  Major overhaul and parameterization of the sound module, to allow
  aircraft-specific sound configuration at runtime.
  Did a lot of code improvements and bug-hunting.
  Creator of most of the ground textures.
  Maintainer of the F-15, F-16, F-104, T-37, PC-7, Fokker 50 and 100 models.
  Keeps the Irix port current.
  Localization support.


Charlie Hotchkiss <clhotch@pacbell.net> 
  Worked on improving and enhancing the HUD code.
  Lots of code style tips and code tweaks ...


Bruce Jackson of NASA <e.b.jackson@larc.nasa.gov> 
  Developed the LaRCsim code under funding by NASA which we use to provide
  the flight model. Bruce has patiently answered my many, many questions.
  http://dcb.larc.nasa.gov/www/DCBStaff/ebj/ebj.html


Maik Justus <fg@mjustus.de>
  Developed YASim's helicopter/rotor logic.
  Implemented aerotowing, water plane and anchor support for YASim, and
  made its gear aware of the surface material.
  Wrote the Bo105 helicopter FDM configuration file.


Ove Kaaven
  Debian packaging of SimGear/FlightGear


Richard Kaszeta <bofh@me.umn.edu>
  Contributed screen buffer to ppm screen shot routine.
  Rich has also helped in the early development of the Flight Gear "altitude 
  hold autopilot module" by teaching Curt Olson the basics of Control Theory 
  and helping him code and debug early versions. Curt's "Boss" Bob Hain
  also contributed <bob@me.umn.edu>.  Further details available at:
  http://www.menet.umn.edu/~curt/fgfs/Docs/Autopilot/AltitudeHold/AltitudeHold.html
  Rich's Homepage: http://www.menet.umn.edu/~kaszeta


Vassilii Khachaturov <vassilii@tarunz.org>
  Support of navaids as autopilot waypoints.
  Switching the tower view to a different tower at any time.
  Various code, GUI, and documentation fixes and updates.


Tom Knienieder <tom@knienieder.com>
  Ported Steve's Audio library first to OpenBSD and IRIX and
  after that also to Win32


Reto Koradi <kor@mol.biol.ethz.ch>
  Helped me get on track with setting up fog effects.
  http://www.mol.biol.ethz.ch/wuthrich/people/kor


Bob Kuehne <rpk@who.net>
  Redid the Makefile system so it is simpler and more robust.


Chris Lampard <c.lampard@ntlworld.com>
  Original exterior geometry for the Cessna 310 U-3A model. Several
  modifications made but most of the exterior is as is converted from
  Chris's original.  The interior cockpit was added by Jim Wilson.


David Luff <david.luff@nottingham.ac.uk>
  Contributed heavily to the IO360 piston engine model.
  Created the ATC intelligent traffic subsystem.
  Creator of TaxiDraw, a program to modify the taxiway layout
  for FlightGear.


Lewis Magruder <blackhawk96@hotmail.com>
  Original A-4 Blue Angels exterior model and textures.  Lewis's work
  is pretty much as converted from the original.  The interior cockpit
  was added by Jim Wilson.


Christian Mayer <flightgear@christianmayer.de>
  Working on a multi-lingual conversion tools for fgfs 
  as a demonstration of technology ;-)
  Contributed code to read msfs formated texture files.
  Working on a completely new weather subsystem.
  Working on a balloon simulator.


David Megginson <david@megginson.com>
  Contributed a patch to allow mouse input to control the yoke.
  Contributed financially towards hard drive space for use by the 
  flight gear project.
  Updates to README.running.
  Working on getting fgfs and ssg to work without textures.
  Also added the new 2D panel and the save/load support.
  Reorganization of the GUI to make it XML configurable.
  Property manager
  Generalized input module
  3D model animation module
  initial take of sound-effects module
  Random ground cover objects
  Vacuum and pitot systems.


Eric Mitchell <mitchell@mars.ark.com>
  Contributed some topnotch scenery textures. His textures were 
  all original creations.


Cameron Moore <cameron@unbeatenpath.net>
  Reigning list admin.
  Provided man pages.
  Self-proclaimed code janitor.
  FAQ maintainer.


Anders Morken <amrken@online.no>
  Maintained the European mirror of the FG web pages.
  Unfortunately this mirror has been taken down due to reglementation
  changes including an enforcement to 10 MB space per subscriber limit 
  which was way too small for the evergrowing FGFS Project's Files.
  He'd be happy to maintain a new one if he could find a place to put it,
  so if you have an idea, contact him!


Alan Murta <amurta@cs.man.ac.uk>
  http://www.cs.man.ac.uk/aig/staff/alan/software/
  Created the Generic Polygon Clipping library


Phil Nelson  <phil@cs.wwu.edu>
  Author of GNU dbm.  gdbm is a set of database routines that use
  extendible hashing and works similar to the standard UNIX dbm routines.


Alexei Novikov <anovikov@heron.itep.ru>
  Created European Scenery
  Contributed a script to turn fgfs scenery into beautifully rendered 
  2d maps.
  Contributed a first draft of a scenery creation howto.


Curt Olson <http://www.flightgear.org/~curt>
  Curt is responsible for overall project and source code management.
  He has his hands in many of the areas, but is primarily responsible
  for the scenery subsystem, as well as much of the infrastructure in
  the sim.
  Handles most parts of the regular scenery rebuild, including lots of
  improvements of the vertex calculation code.
  Added the nw PID based, configurable autopilot code.
  Added the Electrical system.
  Added Runway lighting.


Brian Paul
  His TR Library: http://www.mesa3d.org/brianp/TR.html
  And also Mesa of course: http://www.mesa3d.org


Tony Peden <apeden@earthlink.net>
  Contributions on the flight model front, including a LaRCsim based 
  Cessna 172.  JSBsim: the initial conditions code, a more complete 
  standard atmosphere model, and other bugfixes/additions. 


Robin Peel <robin@cpwd.com>
  Maintains the ever growing worldwide airport, runway, and navigation
  aid database for the Flight Gear project as well as for X-Plane.


Alex Perry <alex.perry@ieee.org>
  Contributed code to more accurately model VSI, DG, Altitude.
  Contributed to the Install and Getting Started manual.


Friedemann Reinhard <mpt218@faupt212.physik.uni-erlangen.de>
  Contributed beginnings of a textured instrument panel.


Frederic Bouvier <frbouvi@wanadoo.fr>
   Added French language support
   Keeps FlightGear MSVC compatible.
   Did a number of code changes to improve the animation code.
   Added a number of animations that improves the visual system quite a lot.
   Did a nice job populating the San Francisco bay area by adding a lot
   of static scenery.


Petter Reinholdtsen <pere@games.no>
  Incorporated the Gnu automake/autoconf system (with libtool).
  This should streamline and standardize the build process for all
  Unix-like platforms.  It should have little effect on IDE type 
  environments since the don't use the Unix make system.


William Riley <riley@technologist.com>
  Contributed code to add "brakes". 
  Patch to support a first joystick with more than two axes.
  World scenery based on vmap0 data.


Andy Ross <andy@plausible.org>
  Contributed a new configurable FDM, "YASim", based on geometry
  information rather than aerodynamic coefficients.
  Added support for placing 2D panel objects in 3D space.
  Modified the HUD code to make it more accurate and added 3D support.
  Modified the UI code to allow a far more flexible grouping system.
  Added the Nasal scripting language and added FlightGear integration.


Paul Schlyter <pausch@saaf.se>  
  Mr. Schlyter provided Durk Talsma with all the information 
  he needed to write the astro code. Mr. S. is also willing 
  to answer astro-related questions whenever one needs to.
  http://welcome.to/pausch


Chris Schoeneman <crs@millpond.engr.sgi.com>
  Contributed some 3d sound playing code for Irix, Win32, and Linux
  It is unclear if this code will be used directly, but it certainly
  will have an influence on the development of our own audio library.


Phil Schubert <philip@zedley.com>
  Contributed various textures and engine modelling.
  http://www.zedley.com/Philip/index.htm
 

Jonathan R Shewchuk <Jonathan_R_Shewchuk@ux4.sp.cs.cmu.edu>
  Author of the Triangle program.  Triangle is used to calculate the
  Delauney triangulation of our irregular terrain.


Gordan Sikic <gsikic@public.srce.hr>
  Contributed a cherokee flight model for LaRCsim.  
  Currently is not working and needs to be debugged.  
  Use configure  --with-flight-model=cherokee
  to build the cherokee instead of the navion.


Michael Smith <msmith99@flash.net>
  Contributed cockpit graphics, 3d models, logos, and other images.
  Project Bonanza - http://members.xoom.com/ConceptSim/index.html


Martin Spott <Martin.Spott@uni-duisburg.de>
  Contributed to the installation / user guide.


Martin Dressler <dr@musicabona.cz>
  Created some outstanding panel instrumentation textures
  for use in full-screen mode.


U.S. Geological Survey
  Provided geographic data used by this project
  http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html


Durk Talsma <d.talsma@chello.nl>
  Accurate Sun, Moon, and Planets. 
  Sun changes color based on position in sky.
  Moon has correct phase and blends well into the sky.
  Planets are correctly positioned and have proper magnitude.
  Help with time functions, gui, and other misc stuff.
  Added the AirTraffic module for scheduled AI airliners and other aircraft.
  2D Cloud layers (nifty).
  http://people.a2000.nl/dtals


UIUC - Department of Aeronautical and Astronautical Engineering
  Contributed modifications to LaRCsim to allow loading of aircraft
  parameters from a file.  These modifications were made as part of an
  icing research project.

  Did the coding and made it all work:
      Jeff Scott <jscott@students.uiuc.edu>
      Bipin Sehgal <bsehgal@uiuc.edu>
      Michael Selig <m-selig@uiuc.edu>

  Helped support the effort
      Jay Thomas <jthomas2@uiuc.edu>
      Eunice Lee <ey-lee@students.uiuc.edu>
      Elizabeth Rendon <mdfhoyos@md.impsat.net.co>
      Sudhi Uppuluri <suppulur@students.uiuc.edu>


Mark Vallevand <Mark.Vallevand@UNISYS.com>
  Contributed some METAR parsing code.
  Contributed some win32 screen printing routines.


Gary R. Van Sickle <tiberius@braemarinc.com>
  Contributed some initial GameGLUT support and other fixes.
  Has done some interesting preliminary work on a binary file format
  http://www.woodsoup.org/projs/ORKiD/fgfs.htm

  Has set up a 'Cygwin Tips' site that has been very helpful to many 
  people in getting a Cygwin Unix-on-Windows build environment set up
  so they can build FG effectively. 
  http://www.woodsoup.org/projs/ORKiD/cygwin.htm


Norman Vine <nhv@yahoo.com>
  Provided more than uncountable URL's to the "FlightGear Community".
  Many performance optimizations throughout the code.  
  Many contributions and much advice for the scenery generation section.
  Lots of windoze related contributions.
  Contributed wgs84 distance and course routines.
  Contributed a great circle route autopilot mode based on wgs84 routines.
  Many other GUI, HUD, and autopilot contributions.
  Contributed a patch to allow mouse input to control view direction.
  Ultra hires tiled screen dumps.
  Contributed the initial 'goto airport' and 'reset' functions
  Contributed the initial http image server code
  Did the build instructions for OpenAL (and SDL) for Cygwin.


Roland Voegtli <voegtli@sanw.unibe.ch>
  Great photorealistic textures.
  Founder of European Scenery Project for X-Plane
  http://www.g-point.com/xpcity/esp/


Carmelo Volpe <carmelo.volpe@mednut.ki.se>
  Contributed some work to porting Flight Gear to the Metro Works 
  development environment (PC/Mac)


Darrell Walisser <dwaliss1@purdue.edu>
  Contributed a large number of MacOS changes and has somehow managed
  to get a pile of code written by a bunch of people who've never seen
  a Mac to compile and run on said platform.
  Provides MacOS-specific info in the docs.


Davud Culp <davidculp2@attbi.com>
  Changed the layout of the conbtrolls section and added a great number
  of extra controls which will prove to be usefull no and for the future.
  Contributed a number of aircraft configuration files, including a T-38 and
  Boeing 737.
  Implemented the AIModels subsystem (originally based on the ATC traffic code)
  and extended it to support ships, aircraft, ballistic objects, thunder-storms,
  and thermals.
  Added a lot of updated to JSBSIm, esp. for the turbine section.


Ed Williams <Ed_Williams@compuserve.com>
  Contributed magnetic variation code (impliments Nima WMM 2000)
  We've also borrowed from Ed's wonderful aviation formulary at various
  times as well.
  http://www.best.com/~williams/index.html


Jim Wilson <jimw@kelcomaine.com>
  Wrote a major overhaul of the viewer code to make it more flexible 
  and modular.  Contributed many small fixes and bug reports.
  Contributed the the pui property browser.
  Contributed to the autopilot.
  Created several excellent 3D aircraft models, including the p-51,
  Wright Flyer and the Boeing 747.


Jean-Claude Wippler <jcw@equi4.com>
  Author of MetaKit - a portable, embeddible database with a portable
  data file format.  This software is not GPL'd but the author is kindly
  allowing us to bundle MetaKit with our code.  MetaKit has a liberal
  X/MIT-style license.  Please see the following URL for more info:
  http://www.equi4.com/metakit


John Wojnaroski <castle@mminternet.com>
  Open Glass Cockpit project
  3d clouds


Lee Elliot <leee@spatial.freeserve.co.uk>
  Author of the YF-23, A-10, Ann225, B-52 and TSR-2 models.
  Did a lot of suggestions for better aircraft modelling, some of which
  resulted in code changes to accomplish them.


Innis Cunningham <innisc@hotmail.com>
  Modelled the 737 and contributed to the T38.


Vivian Meazza <vivian.meazza@lineone.net>
  Added a number of excellent aircraft models including the Hawker Hunter
  and Seahawk.
  Provided realistic wind, gravity and drag calculations for AIBallistic models,
  as well as terrain intersections (impacts) of submodels.
  Added the Fresnel Lens Optical Landing System and AI code for AICarrier and
  AIShip, and implemented the TACAN navigation instrument


David Culp <davidculp2@comcast.net>
  Added the AI model and scenario code which allows non interactive models
  (like aircraft, ships, ballistic models, storms and thermals) to move
  around the scenery in a predefined way. Every model can have it's own
  special characteristics. The thermal model for instance is a non-visible
  model that creates an updraft around it's center.


Mathias Fr<46>hlich <Mathias.Froehlich@gmx.net>
  Implemented the groundcache code which made it possible for aircraft
  to follow the ground precisely and, as a result, made it possible to
  land on aircraft carriers.
  Modified YASim, JSBSim  and LaRCsim to support the groundcache code.
  Reorganized the code to eliminate the viewer jitter for close by objects.


Harald Johnsen <hjohnsen@evc.net>
  Added a new 3D cloud implementation which also works on big-endian machines.
  This code allows for clouds of any types and any shapes (and even deformation
  while moving).
  Implemented volumetric shadowing.


Roy Vegard Ovesen <rvovesen@tiscali.no>
  Implemented the KAP140 autopilot.
  Added a generic, XML configurable, autopilot framework.
  Added an Altitude encoder.
  Added a transponder.
  Made the instruments code much more configurable, it is now possible to only
  include instruments that are actually present.
  Added several high level, configurable filter implementations for use by
  autopilot designers.


Stuart Buchanan <stuart_d_buchanan@yahoo.co.uk>
  Substantial additions to the Getting Started Manual
  Enhancements to the Cessna-310 3d model.
  Added a generic yoke model, a generic throttle quadrant model and a 
  generic pedal set model.


Stefan Seifert <nine@detonation.org>
  Added the save-on-exit option to save the user preferences at program exit.


Space Imaging, Inc  http://www.spaceimaging.com/
  Space Imaging has allowed us to use the images in their archive for
  commercial and non-commercial use, provided the original image can't be
  extracted  from the textures.
  Some (if not all) of the best textures in use by FlightGear wouldn't be
  possible without the satellite images provided by them.


Airservices Australia
  Duncan McCreanor and Diarmuid Tyson created a multiplayer engine for
  FlightGear when putting together a demonstration to show the possibilities
  of using Flightgear as the basis for an Air Traffic 


SkyscraperPage.com  http://skyscraperpage.com
  SkyscraperPage.com has allowed us to use their building diagrams to
  make textures and 3d models of their buildings.


WoodSoup Project  http://www.woodsoup.org
  [ FlightGear no longer uses woodsoup services, but we appreciate
  the support provided to our project during the time they hosted us. ]
  Provided computing resources and services so that the Flight Gear 
  project could have real home.  This includes, web services, 
  ftp services, shell accounts, email lists, dns services, etc.


Robert Allan Zeh <raz@cmg.FCNBD.COM>
  Helped me tremendously in figuring out the Cygnus win32 compiler and
  how to link with .dll's.  With out him the first runable win32
  version of FG would have been impossible.



NOTE:
----

THIS DOCUMENT WAS INITIALLY WRITTEN BY 

Curt L. Olson  <http://www.flightgear.org/~curt>


THE CONTENTS WERE LASTLY RESEARCHED AND UPDATED MARCH, 8 2000

Oliver Delise  <delise@mail.isis.de>


Updated 2001-12-11 by David Megginson, david@megginson.com
Updated 2003-04-17,
Updated 2004-06-01,
Updated 2005-04-02 by Erik Hofman, erik@ehofman.com