This is geomview, produced by Makeinfo version 3.12h from geomview.texi.

INFO-DIR-SECTION Graphics Applications
START-INFO-DIR-ENTRY
* Geomview: (geomview).         The interactive 3D viewing program.
END-INFO-DIR-ENTRY


File: geomview,  Node: Top,  Next: Intro,  Up: (DIR)

   Geomview, the interactive 3D viewing program.

* Menu:

* Intro::		Introduction to Geomview.
* Distrib::	        How to get the latest Geomview distribution.
* Copying::	        The GNU Lesser Public License gives you permission
			  to redistribute Geomview on certain terms;
			  it also explains that there is no warranty.
* History::		History of Geomview's Development.
* Authors::		The Authors of Geomview.
* Platforms::		Supported Platforms.
* Pronunciation::	How to Pronounce ``Geomview''.
* Register::		Let Us Hear From You.
* Overview::		Overview of Geomview.
* Tutorial::		Introductory Tutorial.
* Interaction::		Interacting with Geomview.
* OOGL File Formats::	Formats for Geometry Input.
* Customization::	Modifying the behavior of Geomview.
* Modules::		Programs that use Geomview for graphics display.
* GCL::			gcl: the Geomview Command Language.
* Mathematica::		Mathematica Graphics in Geomview or RenderMan.
* Installation::	Installing Geomview on your computer.
* Support::		Getting Technical Support for Geomview.

* Function Index::	A node for each gcl function.


File: geomview,  Node: Intro,  Next: Distrib,  Prev: Top,  Up: Top

Introduction to Geomview
************************

   Geomview is an interactive program for viewing and manipulating
geometric objects, originally written by staff members of the Geometry
Center at the University of Minnesota, starting in 1991.  It can be used
as a standalone viewer for static objects or as a display engine for
other programs which produce dynamically changing geometry.  It runs on
many kinds of Unix computers, including Linux, SGI, Sun, and HP.  This
manual describes Geomview version 1.8.

   Geomview is free software, available under the terms of the GNU
Lesser Public License; *Note Copying:: for details.

   Geomview and this manual are available for download from
http://www.geomview.org or ftp://ftp.geomview.org

   Permission is granted to make copies of this manual.

   If you have questions or comments about Geomview or this manual,
consider joining in the `geomview-users' mailing list, which is a forum
in which users of Geomview communicate to answer each others' questions
and to share news about what they are doing with Geomview.  The
Geomview authors participate in this list and sometimes post answers to
questions there.  To join the list, send an empty note with 'subscribe'
in the subject line to geomview-users-request@lists.sourceforge.net, or
visit the list web page at
http://lists.sourceforge.net/mailman/listinfo/geomview-users.

   If you find a bug in Geomview, please report it to the Geomview team
by sending a note to software@geomview.org.


File: geomview,  Node: Distrib,  Next: Copying,  Prev: Top,  Up: Top

Distribution
************

   Geomview is "free software"; this means that everyone is free to use
it and free to redistribute it on certain conditions.  Geomview is not
in the public domain; it is copyrighted and there are restrictions on
its distribution, but these restrictions are designed to permit
everything that a good cooperating citizen would want to do.  What is
not allowed is to try to prevent others from further sharing any version
of Geomview that they might get from you.  The precise conditions are
found in the GNU Lesser Public License that comes with Geomview and also
appears following this section.

   One way to get a copy of Geomview is from someone else who has it.
You need not ask for our permission to do so, or tell any one else; just
copy it.  If you have access to the Internet, you can get the latest
distribution version of Geomview by anonymous FTP from ftp.geomview.org,
or through your web browser at http://www.geomview.org .

   You may also receive Geomview when you buy a computer.  Computer
manufacturers are free to distribute copies on the same terms that
apply to everyone else.  These terms require them to give you the full
sources, including whatever changes they may have made, and to permit
you to redistribute the Geomview received from them under the usual
terms of the General Public License.  In other words, the program must
be free for you when you get it, not just free for the manufacturer.


File: geomview,  Node: Copying,  Next: History,  Prev: Distrib,  Up: Top

     NOTE: Geomview is distributed under the GNU LESSER GENERAL PUBLIC
     LICENSE.  For the purposes of this license we think of Geomview as if
     it were a "library", and of Geomview external modules as "programs
     than link with the library".  We do this because we specifically
     want to allow proprietary programs and modules to use Geomview.

GNU LESSER PUBLIC LICENSE
*************************

                      Version 2.1, February 1999

     Copyright (C) 1991, 1999 Free Software Foundation, Inc.
     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
     
     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.
     
     [This is the first released version of the Lesser GPL.  It also counts
      as the successor of the GNU Library Public License, version 2, hence
      the version number 2.1.]

Preamble
========

   The licenses for most software are designed to take away your
freedom to share and change it.  By contrast, the GNU General Public
Licenses are intended to guarantee your freedom to share and change
free software-to make sure the software is free for all its users.

   This license, the Lesser General Public License, applies to some
specially designated software packages-typically libraries-of the Free
Software Foundation and other authors who decide to use it.  You can
use it too, but we suggest you first think carefully about whether this
license or the ordinary General Public License is the better strategy
to use in any particular case, based on the explanations below.

   When we speak of free software, we are referring to freedom of use,
not price.  Our General Public Licenses are designed to make sure that
you have the freedom to distribute copies of free software (and charge
for this service if you wish); that you receive source code or can get
it if you want it; that you can change the software and use pieces of
it in new free programs; and that you are informed that you can do
these things.

   To protect your rights, we need to make restrictions that forbid
distributors to deny you these rights or to ask you to surrender these
rights.  These restrictions translate to certain responsibilities for
you if you distribute copies of the library or if you modify it.

   For example, if you distribute copies of the library, whether gratis
or for a fee, you must give the recipients all the rights that we gave
you.  You must make sure that they, too, receive or can get the source
code.  If you link other code with the library, you must provide
complete object files to the recipients, so that they can relink them
with the library after making changes to the library and recompiling
it.  And you must show them these terms so they know their rights.

   We protect your rights with a two-step method: (1) we copyright the
library, and (2) we offer you this license, which gives you legal
permission to copy, distribute and/or modify the library.

   To protect each distributor, we want to make it very clear that
there is no warranty for the free library.  Also, if the library is
modified by someone else and passed on, the recipients should know that
what they have is not the original version, so that the original
author's reputation will not be affected by problems that might be
introduced by others.

   Finally, software patents pose a constant threat to the existence of
any free program.  We wish to make sure that a company cannot
effectively restrict the users of a free program by obtaining a
restrictive license from a patent holder.  Therefore, we insist that
any patent license obtained for a version of the library must be
consistent with the full freedom of use specified in this license.

   Most GNU software, including some libraries, is covered by the
ordinary GNU General Public License.  This license, the GNU Lesser
General Public License, applies to certain designated libraries, and is
quite different from the ordinary General Public License.  We use this
license for certain libraries in order to permit linking those
libraries into non-free programs.

   When a program is linked with a library, whether statically or using
a shared library, the combination of the two is legally speaking a
combined work, a derivative of the original library.  The ordinary
General Public License therefore permits such linking only if the
entire combination fits its criteria of freedom.  The Lesser General
Public License permits more lax criteria for linking other code with
the library.

   We call this license the "Lesser" General Public License because it
does Less to protect the user's freedom than the ordinary General
Public License.  It also provides other free software developers Less
of an advantage over competing non-free programs.  These disadvantages
are the reason we use the ordinary General Public License for many
libraries.  However, the Lesser license provides advantages in certain
special circumstances.

   For example, on rare occasions, there may be a special need to
encourage the widest possible use of a certain library, so that it
becomes a de-facto standard.  To achieve this, non-free programs must
be allowed to use the library.  A more frequent case is that a free
library does the same job as widely used non-free libraries.  In this
case, there is little to gain by limiting the free library to free
software only, so we use the Lesser General Public License.

   In other cases, permission to use a particular library in non-free
programs enables a greater number of people to use a large body of free
software.  For example, permission to use the GNU C Library in non-free
programs enables many more people to use the whole GNU operating
system, as well as its variant, the GNU/Linux operating system.

   Although the Lesser General Public License is Less protective of the
users' freedom, it does ensure that the user of a program that is
linked with the Library has the freedom and the wherewithal to run that
program using a modified version of the Library.

   The precise terms and conditions for copying, distribution and
modification follow.  Pay close attention to the difference between a
"work based on the library" and a "work that uses the library".  The
former contains code derived from the library, whereas the latter must
be combined with the library in order to run.

    TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  0. This License Agreement applies to any software library or other
     program which contains a notice placed by the copyright holder or
     other authorized party saying it may be distributed under the
     terms of this Lesser General Public License (also called "this
     License").  Each licensee is addressed as "you".

     A "library" means a collection of software functions and/or data
     prepared so as to be conveniently linked with application programs
     (which use some of those functions and data) to form executables.

     The "Library", below, refers to any such software library or work
     which has been distributed under these terms.  A "work based on the
     Library" means either the Library or any derivative work under
     copyright law: that is to say, a work containing the Library or a
     portion of it, either verbatim or with modifications and/or
     translated straightforwardly into another language.  (Hereinafter,
     translation is included without limitation in the term
     "modification".)

     "Source code" for a work means the preferred form of the work for
     making modifications to it.  For a library, complete source code
     means all the source code for all modules it contains, plus any
     associated interface definition files, plus the scripts used to
     control compilation and installation of the library.

     Activities other than copying, distribution and modification are
     not covered by this License; they are outside its scope.  The act
     of running a program using the Library is not restricted, and
     output from such a program is covered only if its contents
     constitute a work based on the Library (independent of the use of
     the Library in a tool for writing it).  Whether that is true
     depends on what the Library does and what the program that uses
     the Library does.

  1. You may copy and distribute verbatim copies of the Library's
     complete source code as you receive it, in any medium, provided
     that you conspicuously and appropriately publish on each copy an
     appropriate copyright notice and disclaimer of warranty; keep
     intact all the notices that refer to this License and to the
     absence of any warranty; and distribute a copy of this License
     along with the Library.

     You may charge a fee for the physical act of transferring a copy,
     and you may at your option offer warranty protection in exchange
     for a fee.

  2. You may modify your copy or copies of the Library or any portion
     of it, thus forming a work based on the Library, and copy and
     distribute such modifications or work under the terms of Section 1
     above, provided that you also meet all of these conditions:

       a. The modified work must itself be a software library.

       b. You must cause the files modified to carry prominent notices
          stating that you changed the files and the date of any change.

       c. You must cause the whole of the work to be licensed at no
          charge to all third parties under the terms of this License.

       d. If a facility in the modified Library refers to a function or
          a table of data to be supplied by an application program that
          uses the facility, other than as an argument passed when the
          facility is invoked, then you must make a good faith effort
          to ensure that, in the event an application does not supply
          such function or table, the facility still operates, and
          performs whatever part of its purpose remains meaningful.

          (For example, a function in a library to compute square roots
          has a purpose that is entirely well-defined independent of the
          application.  Therefore, Subsection 2d requires that any
          application-supplied function or table used by this function
          must be optional: if the application does not supply it, the
          square root function must still compute square roots.)

     These requirements apply to the modified work as a whole.  If
     identifiable sections of that work are not derived from the
     Library, and can be reasonably considered independent and separate
     works in themselves, then this License, and its terms, do not
     apply to those sections when you distribute them as separate
     works.  But when you distribute the same sections as part of a
     whole which is a work based on the Library, the distribution of
     the whole must be on the terms of this License, whose permissions
     for other licensees extend to the entire whole, and thus to each
     and every part regardless of who wrote it.

     Thus, it is not the intent of this section to claim rights or
     contest your rights to work written entirely by you; rather, the
     intent is to exercise the right to control the distribution of
     derivative or collective works based on the Library.

     In addition, mere aggregation of another work not based on the
     Library with the Library (or with a work based on the Library) on
     a volume of a storage or distribution medium does not bring the
     other work under the scope of this License.

  3. You may opt to apply the terms of the ordinary GNU General Public
     License instead of this License to a given copy of the Library.
     To do this, you must alter all the notices that refer to this
     License, so that they refer to the ordinary GNU General Public
     License, version 2, instead of to this License.  (If a newer
     version than version 2 of the ordinary GNU General Public License
     has appeared, then you can specify that version instead if you
     wish.)  Do not make any other change in these notices.  ^L Once
     this change is made in a given copy, it is irreversible for that
     copy, so the ordinary GNU General Public License applies to all
     subsequent copies and derivative works made from that copy.

     This option is useful when you wish to copy part of the code of
     the Library into a program that is not a library.

  4. You may copy and distribute the Library (or a portion or
     derivative of it, under Section 2) in object code or executable
     form under the terms of Sections 1 and 2 above provided that you
     accompany it with the complete corresponding machine-readable
     source code, which must be distributed under the terms of Sections
     1 and 2 above on a medium customarily used for software
     interchange.

     If distribution of object code is made by offering access to copy
     from a designated place, then offering equivalent access to copy
     the source code from the same place satisfies the requirement to
     distribute the source code, even though third parties are not
     compelled to copy the source along with the object code.

  5. A program that contains no derivative of any portion of the
     Library, but is designed to work with the Library by being
     compiled or linked with it, is called a "work that uses the
     Library".  Such a work, in isolation, is not a derivative work of
     the Library, and therefore falls outside the scope of this License.

     However, linking a "work that uses the Library" with the Library
     creates an executable that is a derivative of the Library (because
     it contains portions of the Library), rather than a "work that
     uses the library".  The executable is therefore covered by this
     License.  Section 6 states terms for distribution of such
     executables.

     When a "work that uses the Library" uses material from a header
     file that is part of the Library, the object code for the work may
     be a derivative work of the Library even though the source code is
     not.  Whether this is true is especially significant if the work
     can be linked without the Library, or if the work is itself a
     library.  The threshold for this to be true is not precisely
     defined by law.

     If such an object file uses only numerical parameters, data
     structure layouts and accessors, and small macros and small inline
     functions (ten lines or less in length), then the use of the object
     file is unrestricted, regardless of whether it is legally a
     derivative work.  (Executables containing this object code plus
     portions of the Library will still fall under Section 6.)

     Otherwise, if the work is a derivative of the Library, you may
     distribute the object code for the work under the terms of Section
     6.  Any executables containing that work also fall under Section 6,
     whether or not they are linked directly with the Library itself.

  6. As an exception to the Sections above, you may also combine or
     link a "work that uses the Library" with the Library to produce a
     work containing portions of the Library, and distribute that work
     under terms of your choice, provided that the terms permit
     modification of the work for the customer's own use and reverse
     engineering for debugging such modifications.

     You must give prominent notice with each copy of the work that the
     Library is used in it and that the Library and its use are covered
     by this License.  You must supply a copy of this License.  If the
     work during execution displays copyright notices, you must include
     the copyright notice for the Library among them, as well as a
     reference directing the user to the copy of this License.  Also,
     you must do one of these things:

       a. Accompany the work with the complete corresponding
          machine-readable source code for the Library including
          whatever changes were used in the work (which must be
          distributed under Sections 1 and 2 above); and, if the work
          is an executable linked with the Library, with the complete
          machine-readable "work that uses the Library", as object code
          and/or source code, so that the user can modify the Library
          and then relink to produce a modified executable containing
          the modified Library.  (It is understood that the user who
          changes the contents of definitions files in the Library will
          not necessarily be able to recompile the application to use
          the modified definitions.)

       b. Use a suitable shared library mechanism for linking with the
          Library.  A suitable mechanism is one that (1) uses at run
          time a copy of the library already present on the user's
          computer system, rather than copying library functions into
          the executable, and (2) will operate properly with a modified
          version of the library, if the user installs one, as long as
          the modified version is interface-compatible with the version
          that the work was made with.

       c. Accompany the work with a written offer, valid for at least
          three years, to give the same user the materials specified in
          Subsection 6a, above, for a charge no more than the cost of
          performing this distribution.

       d. If distribution of the work is made by offering access to copy
          from a designated place, offer equivalent access to copy the
          above specified materials from the same place.

       e. Verify that the user has already received a copy of these
          materials or that you have already sent this user a copy.

     For an executable, the required form of the "work that uses the
     Library" must include any data and utility programs needed for
     reproducing the executable from it.  However, as a special
     exception, the materials to be distributed need not include
     anything that is normally distributed (in either source or binary
     form) with the major components (compiler, kernel, and so on) of
     the operating system on which the executable runs, unless that
     component itself accompanies the executable.

     It may happen that this requirement contradicts the license
     restrictions of other proprietary libraries that do not normally
     accompany the operating system.  Such a contradiction means you
     cannot use both them and the Library together in an executable
     that you distribute.

  7. You may place library facilities that are a work based on the
     Library side-by-side in a single library together with other
     library facilities not covered by this License, and distribute
     such a combined library, provided that the separate distribution
     of the work based on the Library and of the other library
     facilities is otherwise permitted, and provided that you do these
     two things:

       a. Accompany the combined library with a copy of the same work
          based on the Library, uncombined with any other library
          facilities.  This must be distributed under the terms of the
          Sections above.

       b. Give prominent notice with the combined library of the fact
          that part of it is a work based on the Library, and explaining
          where to find the accompanying uncombined form of the same
          work.

  8. You may not copy, modify, sublicense, link with, or distribute the
     Library except as expressly provided under this License.  Any
     attempt otherwise to copy, modify, sublicense, link with, or
     distribute the Library is void, and will automatically terminate
     your rights under this License.  However, parties who have
     received copies, or rights, from you under this License will not
     have their licenses terminated so long as such parties remain in
     full compliance.

  9. You are not required to accept this License, since you have not
     signed it.  However, nothing else grants you permission to modify
     or distribute the Library or its derivative works.  These actions
     are prohibited by law if you do not accept this License.
     Therefore, by modifying or distributing the Library (or any work
     based on the Library), you indicate your acceptance of this
     License to do so, and all its terms and conditions for copying,
     distributing or modifying the Library or works based on it.

 10. Each time you redistribute the Library (or any work based on the
     Library), the recipient automatically receives a license from the
     original licensor to copy, distribute, link with or modify the
     Library subject to these terms and conditions.  You may not impose
     any further restrictions on the recipients' exercise of the rights
     granted herein.  You are not responsible for enforcing compliance
     by third parties with this License.

 11. If, as a consequence of a court judgment or allegation of patent
     infringement or for any other reason (not limited to patent
     issues), conditions are imposed on you (whether by court order,
     agreement or otherwise) that contradict the conditions of this
     License, they do not excuse you from the conditions of this
     License.  If you cannot distribute so as to satisfy simultaneously
     your obligations under this License and any other pertinent
     obligations, then as a consequence you may not distribute the
     Library at all.  For example, if a patent license would not permit
     royalty-free redistribution of the Library by all those who
     receive copies directly or indirectly through you, then the only
     way you could satisfy both it and this License would be to refrain
     entirely from distribution of the Library.

     If any portion of this section is held invalid or unenforceable
     under any particular circumstance, the balance of the section is
     intended to apply, and the section as a whole is intended to apply
     in other circumstances.

     It is not the purpose of this section to induce you to infringe any
     patents or other property right claims or to contest validity of
     any such claims; this section has the sole purpose of protecting
     the integrity of the free software distribution system which is
     implemented by public license practices.  Many people have made
     generous contributions to the wide range of software distributed
     through that system in reliance on consistent application of that
     system; it is up to the author/donor to decide if he or she is
     willing to distribute software through any other system and a
     licensee cannot impose that choice.

     This section is intended to make thoroughly clear what is believed
     to be a consequence of the rest of this License.

 12. If the distribution and/or use of the Library is restricted in
     certain countries either by patents or by copyrighted interfaces,
     the original copyright holder who places the Library under this
     License may add an explicit geographical distribution limitation
     excluding those countries, so that distribution is permitted only
     in or among countries not thus excluded.  In such case, this
     License incorporates the limitation as if written in the body of
     this License.

 13. The Free Software Foundation may publish revised and/or new
     versions of the Lesser General Public License from time to time.
     Such new versions will be similar in spirit to the present version,
     but may differ in detail to address new problems or concerns.

     Each version is given a distinguishing version number.  If the
     Library specifies a version number of this License which applies
     to it and "any later version", you have the option of following
     the terms and conditions either of that version or of any later
     version published by the Free Software Foundation.  If the Library
     does not specify a license version number, you may choose any
     version ever published by the Free Software Foundation.

 14. If you wish to incorporate parts of the Library into other free
     programs whose distribution conditions are incompatible with these,
     write to the author to ask for permission.  For software which is
     copyrighted by the Free Software Foundation, write to the Free
     Software Foundation; we sometimes make exceptions for this.  Our
     decision will be guided by the two goals of preserving the free
     status of all derivatives of our free software and of promoting
     the sharing and reuse of software generally.

                                NO WARRANTY

 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
     WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE
     LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
     HOLDERS AND/OR OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT
     WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT
     NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
     FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO THE
     QUALITY AND PERFORMANCE OF THE LIBRARY IS WITH YOU.  SHOULD THE
     LIBRARY PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY
     SERVICING, REPAIR OR CORRECTION.

 16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
     WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY
     MODIFY AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE
     LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
     INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR
     INABILITY TO USE THE LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF
     DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU
     OR THIRD PARTIES OR A FAILURE OF THE LIBRARY TO OPERATE WITH ANY
     OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
     ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

                      END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs
=============================================

   If you develop a new library, and you want it to be of the greatest
possible use to the public, we recommend making it free software that
everyone can redistribute and change.  You can do so by permitting
redistribution under these terms (or, alternatively, under the terms of
the ordinary General Public License).

   To apply these terms, attach the following notices to the library.
It is safest to attach them to the start of each source file to most
effectively convey the exclusion of warranty; and each file should have
at least the "copyright" line and a pointer to where the full notice is
found.

     ONE LINE TO GIVE THE LIBRARY'S NAME AND A BRIEF IDEA OF WHAT IT DOES.
     Copyright (C) <year>  NAME OF AUTHOR
     
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
     
     This library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Lesser General Public License for more details.
     
     You should have received a copy of the GNU Lesser General Public
     License along with this library; if not, write to the Free Software
     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA

   Also add information on how to contact you by electronic and paper
mail.

   You should also get your employer (if you work as a programmer) or
your school, if any, to sign a "copyright disclaimer" for the library,
if necessary.  Here is a sample; alter the names:

     Yoyodyne, Inc., hereby disclaims all copyright interest in the
     library `Frob' (a library for tweaking knobs) written by James
     Random Hacker.
     
     <signature of Ty Coon>, 1 April 1990
     Ty Coon, President of Vice

   That's all there is to it!


File: geomview,  Node: History,  Next: Authors,  Prev: Top,  Up: Top

History of Geomview's Development
*********************************

   Geomview was originally written at the Geometry Center at the
University of Minnesota in Minneapolis.  The Geometry Center was a
research and education center funded by the National Science
Foundation, with a mission to promote research and communication of
mathematics.  Much of the work there involved the use of computers to
help visualize mathematical concepts.

   The project that eventually led to Geomview began in the summer of
1988 with the work of Pat Hanrahan on a viewing program called
MinneView.  Shortly thereafter Charlie Gunn begin developing OOGL
(Object Oriented Graphics Language) in conjunction with MinneView.
Many people contributed to OOGL and MinneView, including Stuart Levy,
Mark Meuer, Tamara Munzner, Steve Anderson, Mario Lopez, Todd Kaplan.

   In 1991 the staff of the Geometry Center began work on a new improved
version of OOGL, and a new and improved viewing program, which they
called Geomview.  At that time essentially the only game in town for
interactive 3D graphics was Silicon Graphics (SGI), so Geomview was
developed initially on SGI workstations, using IRIS GL.  The first
version was finished in January of 1992.  It immediately became very
popular among visitors to the Geometry Center, and through the Center's
ftp archive (this was before the web) people at other institutions began
using it too.

   In addition to SGI workstations the Geometry Center had quite a few
NeXT stations, so soon after Geomview was running on SGIs the staff
developed a version for NeXTStep as well.  By this time there were
several thousand people using it around the world.

   A few years later the staff ported Geomview to X windows and OpenGL,
and eventually, with the demise of NeXT, the NeXT version fell by the
wayside.

   In its mission to foster communication among researchers and
educators, the Geometry Center developed a web site, www.geom.umn.edu,
in late 1993.  It was one of the first 300 web sites in existence.  A
part of the web site was of course devoted to Geomview, and helped to
spread the word about its existence.

   The Geometry Center closed its "brick and mortar" facilities in
August of 1998 (NSF cut its funding), but the web site continued to
exist, and Geomview continued to be very popular around the world.  In
December of 1999 some of the former Geometry Center staff set up
http://www.geomview.org as a permanent home on the web for Geomview.

   Geomview's original authors, as well as a number of other volunteers
around the world, are still actively involved in using and developing
Geomview.


File: geomview,  Node: Authors,  Next: Platforms,  Prev: History,  Up: Intro

Authors
=======

   Tamara Munzner, Stuart Levy, and Mark Phillips are the original
authors of Geomview. Celeste Fowler, Charlie Gunn, and Nathaniel
Thurston also made significant contributions.  Daniel Krech and Scott
Wisdom did the NeXTStep and RenderMan port, and Daeron Meyer and Tim
Rowley did the port to X windows.  Many other Geometry Center staff
members, as well as several people elsewhere, also contributed.

   Mark Phillips wrote this manual, with substantial help from Stuart
Levy and Tamara Munzner.  Countless Geomview users have also been of
great help by reading it and pointing out mistakes.


File: geomview,  Node: Platforms,  Next: Pronunciation,  Prev: Authors,  Up: Top

Supported Platforms
*******************

   Geomview runs on a wide variety of Unix systems. It has been tested
on each of the following systems: Linux, FreeBSD, SGI, Sun either
(Sun-OS 4.1.x and Solaris), HP RISC, Dec Alpha, RS/6000, and NeXT.
Precompiled distributions are available for all of these systems.
Using either OpenGL or the generic X11 renderer it can probably be
compiled on other Unix systems as well.

   There is not a version of Geomview for Microsoft Windows.  The main
reason for this is that at the time when Geomview was written, personal
computers were not fast enough to make interactive 3D graphics feasible,
and by the time fast-enough PCs came around, the Geometry Center, where
Geomview was developed, was in the process of being closed.  The staff
started work on a port to Windows but was not able to finish it before
the Center shut down.

   If you would like to see a version of Geomview for Windows, you can
contribute to its development in several ways.  *Note Contributing::
for details.

   There is also no version of Geomview for Macintosh.


File: geomview,  Node: Pronunciation,  Next: Register,  Prev: Platforms,  Up: Top

How to Pronounce "Geomview"
***************************

   The word 'Geomview' is a combination of the first syllable of the
word 'geometry', and the word 'view'. The authors pronounce it with the
accent on the first syllable

       GE-om-view

   Some people put the accent on the second syllable, where it falls in
the word 'geometry', but the original authors, who invented the name,
prefer the accent-on-first-syllable pronunciation.


File: geomview,  Node: Register,  Next: Overview,  Prev: Pronunciation,  Up: Top

Let Us Hear From You
********************

   The developers of Geomview would like to find out how you are using
Geomview.  We use this information in deciding what features to focus
on, and in finding ways to continue to support its development.  If you
find Geomview useful, please send us a letter telling us what you are
doing with it.  We may include a link to your work on the geomview.org
web site (but we'll ask you about this before doing so).

   Please send the letter via email to `register@geomview.org'.

   If you are interested in contributing to the development of Geomview,
there are several things you can do.  *Note Contributing:: for details.


File: geomview,  Node: Overview,  Next: Tutorial,  Prev: Register,  Up: Top

Overview
********

   Geomview's main purpose is to display objects whose geometry is
given, allowing interactive control over details such as point of view,
speed of movement, appearance of surfaces and lines, and so on.
Geomview can handle any number of objects and allows both separate and
collective control over them.

   The simplest way to use Geomview is as a standalone viewer to see
and manipulate objects.  It can display objects described in a variety
of file formats.  It comes with a wide variety of example objects, and
you can create your own objects.

   You can also use Geomview to handle the display of data coming from
another program that is running simultaneously.  As the other program
changes the data, the Geomview image reflects the changes.  Programs
that generate objects and use Geomview to display them are called
_external modules_.  External modules can control almost all aspects of
Geomview.  The idea here is that many aspects of the display and
interaction parts of geometry software are independent of the geometric
content and can be collected together in a single piece of software
that can be used in a wide variety of situations.  The author of the
external module can then concentrate on implementing the desired
algorithms and leave the display aspects to Geomview.  Geomview comes
with a collection of sample external modules, and this manual describes
how to write your own.

   Geomview is the product of an effort at the Geometry Center to
provide interactive geometry software that is particularly appropriate
for mathematics research and education.  In particular, Geomview can
display things in hyperbolic and spherical space as well as Euclidean
space.

   Geomview allows multiple independently controllable objects and
cameras.  It provides interactive control for motion, appearances
(including lighting, shading, and materials), picking on an object,
edge or vertex level, snapshots in SGI image file or Renderman RIB
format, and adding or deleting objects is provided through direct mouse
manipulation, control panels, and keyboard shortcuts.

   Geomview supports the following simple data types: polyhedra with
shared vertices (.off), quadrilaterals, rectangular meshes, vectors,
and Bezier surface patches of arbitrary degree including rational
patches. Object hierarchies can be constructed with lists of objects
and instances of object(s) transformed by one or many 4x4 matrices.
Arbitrary portions of changing hierarchies may be transmitted by
creating named references.

   Geomview can display 3-D graphics output from Mathematica and Maple.

