                     Persistence of Vision(tm) Ray Tracer
                         POV-Ray(tm) Version 3.6

                  POV-Ray GUI Extension License Agreement
                               Version 1.02

                       GENERAL GUIEXT LICENSE AGREEMENT

This  document  pertains  to  the  creation  and distribution of the custom GUI
Extensions  DLL's  (hereafter  referred  to  as  "GUIEXT'S")  for the Microsoft
Windows  version   of  the   Persistence  of   Vision(tm)  Ray   Tracer  a.k.a.
POV-Ray(tm).  It   is  additional   to  the   POV-Ray  end-user   license  (aka
'POVLEGAL.DOC'). For you to use  the GUIEXT interface, our sample  source code,
and to comply with the terms of  this license, it is also necessary for  you to
agree to and comply with the terms of the end-user license.

                             USAGE PROVISIONS

GUI Extensions for  POV-Ray for Windows  must comply with  this license. A  GUI
Extension DLL is required to contain  the text of an agreement which  refers to
this document. If  this text is  not present it  will not be  loaded by POV-Ray
for Windows (hereafter referred to as povwin.)

The text itself  referred to above  is worded in  an exact and  specific manner
and is Copyright  1996 by Christopher  J. Cason. This  document will grant  you
permission to  include this  copyrighted text  in your  Extension DLL  provided
that you comply  with all terms  and conditions herein.  Failure to do  so will
void any permission to use that text  and also to the usage of the  programming
interface into POV-Ray for Windows and of the demonstration source code.

Extensions may be based on the  sample GUIEXT source code we provide.  That is,
we explicitly permit you to re-use  our demonstration source code (and in  fact
encourage it, since it helps ensure  that you comply with our standards.)  This
permission does not extend to other POV-Ray source files.

Extensions  may  be  written  in  any  programming language compatible with the
requirements for the interface.

If you violate this licence it is automatically revoked for all GUIEXT's  which
you have written or distributed ; past, present, or future.

The authors and copyright holders of  POV-Ray assumes NO LIABILITY for the  use
or  misuse  of  GUIEXT's.  By  accepting  this  licence  you  agree  to totally
indemnify and hold harmless Persistence  of Vision Raytracer Pty. Ltd.  and its
associates  (as  defined  in  the  POV-Ray  v3.6  end-user  license)  from  any
consequences of  any sort  arising directly  or indirectly  from the existance,
non-existance,  use  or  failure  to  use,   of  your  GUIEXT,  or  any   other
circumstance related to  it. This applies  even if the  problem is caused  by a
bug in POV-Ray itself.

You must   agree that   under no   circumstances will   Persistence of   Vision
Raytracer  Pty.  Ltd.  or  its  associates   be  liable  in  any manner, shape,
fashion or form, arising out of  their approval, non-approval, or  cancellation
of your use of this licence, nor for   any decision made to stop, prevent,   or
otherwise disallow  distribution   of  any  item   covered  by  this   licence,
nor  for  any  comments  made  regarding   the  use  or  operation, quality, or
general usefulness  of the  GUIEXT or  related items.  You must  agree that the
POV-Team has  the   right to  change this   licence or  the   GUIEXT  interface
specificaton  at any time  and that you have no recourse if this occurs.

If you do  not agree to  any of the  preceding (or following)  then you are not
granted a licence and therefore may not use the GUIEXT interface or the  sample
source code.

                          INTENTION OF THIS LICENCE

Broadly, the intention of this licence is -

  o to protect POV-Ray users from poor-quality GUIEXT's.
  o to protect the POV-Team members from unnecessary support work caused
    by other person's GUI Extensions.
  o to prevent persons from taking unreasonable commercial advantage of
    our freeware program, POV-Ray for Windows.

                                RECOMMENDATIONS

We  recommend  (but  do  not  require)  that  GUIEXT's be distributed in a .ZIP
archive. The name of the archive should  be the name of the GUIEXT DLL.  If the
archive contains more than one DLL, it must be the name of the main DLL. It  is
permissable to  form a  contraction of  a DLL  name if  it is  more than  eight
characters, so that it will form a 8.3 archive filename.

GUIEXT DLL's should have the file extension .PGE rather than .DLL.

                              LICENCE CONDITIONS

Extensions  are  not  permitted  to   display  splash  screens  or  any   other
notification  that  they  are  loaded  other  than functionally essential ones,
unless  the  user  explicitly  activates  such  by  selecting them from the GUI
Extensions menu.

Extensions  must  not  use  the  reserved  GUIEXT  ID's  00-15  when  modifying
PVENGINE.INI.

No file  included with  a GUIEXT,  including the  GUIEXT itself,  may alter any
POV-Ray for  Windows file,  including executables  and INI  files, except under
the following circumstances -

  o it has been granted specific permission by Persistence of Vision Raytracer
    Pty. Ltd. to do so, or
  o it is the standard INI file, POVRAY.INI, or a user-specified INI file,
    and the user has been explicitly asked for permission, or
  o it is PVENGINE.INI, and the modification is of the [GIUExtensions]
    section, and the ID used is not in the range 00-15.
  o any other file not specifically excluded, and the user has been asked
    permission for the modification.

Specifically excluded (without limitation) are -

  o POV-Ray for Windows executables, including DLL's, or any other module
    that contains executable or machine code.

Files in  the above  'specifically excluded'  category may  never be  modified,
including while they are  in memory or after  they are loaded by  the operating
system.

Extensions  are  not  permitted  to  take  any action that could jeopardise the
correct operation of POV-Ray.

Extensions are not permitted to use "back door's", or undocumented  interfaces,
to access POV-Ray functions,  without explicit written permission.  A interface
is not considered documented if it is only documented in a source code file.

An  exception  is  granted  for  any  function or interface demonstrated in the
sample  extension  source  code  provided  with  the POV-Ray for Windows source
code.

Extensions may  not show  or do  anything that  may suggest,  imply, or cause a
person  to  believe  that  they  are   endorsed  by  the  POV-Ray  authors   or
distributors, or that they are part of POV-Ray itself.

EXCEPT BY  WRITTEN AGREEMENT,  EXTENSIONS AND  ANY PROGRAMS  THEY INTERACT WITH
MUST BE FREEWARE AND  PROVIDE FULL SOURCE. The  source code need not  be in the
same archive  but must  be freely  available. Persistance  of Vision  Raytracer
Pty. Ltd.  may grant  authors permission  to create  a shareware  or commercial
GUIEXT at its discretion.

GUIEXT's may  not perform  any function  that is  intended to  avoid the  above
clause. This includes (but is not  limited to) a freeware GUIEXT being  written
solely  for  the  purpose  of  allowing  the  use  of a commercial or shareware
program. GUIEXT's in this category must be treated as above.

Extension authors with a genuine  reason for performing the above  function, or
who have (or  will have) a  good quality value-added  function in or  available
via a GUIEXT, and  who want to charge  money for it, should  not be discouraged
by the  above. Just  write to  us ;  we're reasonable  people and  want only to
protect  our  freeware  program  from  unreasonable commercial exploitation. If
your idea is non-trivial you've got a good chance of receiving permission.  See
POVLEGAL.DOC for contact information.

Extension authors  are required  to build  their real  name and  a valid  email
address  into  the  DLL.  The  email  address  must be valid for at least three
months from  any time  the extension  is distributed  by the  author or someone
acting for them. This information must be presented via the correct  interface,
as documented in the demonstration source code.

It must  be made  clear in  all documentation  regarding the  GUIEXT that it is
neither supported  nor endorsed  by the  POV-Team. It  must be  made clear that
users are NOT to contact the POV-Team for support on GUIEXT's.

The GUIEXT  must contain  sufficient documentation  for it  to be  used without
referring to the  author or other  information sources, except  when the nature
of the GUIEXT makes that impossible.

GUIEXT's  must  provide  a  menu  handle  to  povwin  containing  at  least two
functional  entries  ;  one  titled  'Enabled'  and  one titled 'About'.  It is
permissable  to  add  words  after  the  word  'About'. The Enabled entry, when
activated, must toggle the extension between a loaded-and-enabled state, and  a
loaded-but- disabled state.  This setting must  be persistent ;  i.e. it should
be preserved  in a  disk file  or other  method of  storage such  that when the
GUIEXT is next loaded the same state is restored.

The About entry  must show an  About box which,  at the very  least, states the
extension's  full  name  and  purpose,  the  name  of  the  author, their email
address, and  a disclaimer  stating that  Persistance of  Vision Raytracer Pty.
Ltd. is not responsible for this GUIEXT.

GUIEXT's  must  provide  'tip'  text  to  POV-Ray  for  Windows via the defined
interface, describing what a particular menu entry does, on demand.

