
 - PVMPOV -                             written by Andreas Dilger, June 1 1995
                                                  and Harald Deischinger, 1997
                                                modified by Jakob Flierl, 1999


*****      NOTE - This is an UNOFFICIAL modification to POV-Ray 3.1e       *****

** DO NOT SEND PROBLEM REPORTS TO THE POV TEAM REGARDING THESE MODIFICATIONS. **

The author disclaims all warranties with regard to this software, including 
all implied warranties of merchant-ability and fitness.  The code is simply 
distributed as it is. 


General information
-------------------

"I only ask that credit (or blame) is attributed to me for the original work."
                                                             - Brad Kline

The original author of the PVM POV-Ray patch on which this is based is Brad
Kline, of Cray Research, Inc.  Because of problems running the original code at
my site, and a desire to learn more about PVM for my Master's work, I have
changed large portions to not only be more user-friendly about reporting
errors, but also hopefully more robust and faster.
                                                         - Andreas Dilger

Because Andreas has other things to do, I have taken over the part of
PVMing POV-Ray 3.1. If you have problems with this program, don't be afraid
to ask me for help. 

Please send me a mail, if you're using PVMPOV Version 3.1e.2. 
                                                           - Jakob Flierl
Contact
-------
email    : flierl@luga.de

Important information/Problems
------------------------------

* This version is not tested very vell, so it is very likely, that you
  find some errors - please tell me about them.

  Especially the very time consuming new features (radiosity) are not
  really tested.

* Shellout commands are always done by the master process.

* Now PVMPOV also supports animations. PVMPOV computes multiply frames
  simultaniously, so it is not possible to do "recursive animations"
  (like the desk example in povscn/level3). You have to run PVMPOV extra
  for each frame.

  All the pre-scene shellouts are done in the correct order, and the same
  for the post-scene shellouts. BUT for example the pre-scene shellout for 
  frame 2, will be executed before the post-scene shellout for frame 1!

  Field Rendering (+UF) is not working yet.

* The X11 display now displays everything. 
  There are no longer "forgotten blocks".

* The master process of PVMPOV does not parse the input file. So you will
  NOT see errors in the .pov file - the slaves will simply not start.
  So you should turn off PVM support (pvm=off or -N) while developing your
  scene file.

  You will also get no warning, if the slave can not find the input file.
  The slave will simply never ask for work. Check "/tmp/pvml.<uid>" for
  errors with the slaves.

* You might get errors, that pvm can not find the executables for the slaves.
  You can solve this in lot's of ways. 
  - Start pvmpov with an absolute filename,
    e.g. '/usr/bin/pvmpov ...'
  - Specify the absolute path for the slaves, 
    e.g. 'pvmpov -NS/usr/bin/pvmpov ...'
    You can set this option in you '.povrayrc' file.
  - Move your executables into ~/pvm3/bin/ARCH
  - Use the 'ep=PATH' option in your hostfile 
  Read the PVM documentation for more information.

* When using automount you might have the problem, that the slaves can't
  change to the working directory. Use the +ND (pvm_wd) option.
  Calling pvmpov with "+ND$PWD" should solve the problem.

* For more information see "PVMPOV.1st_scene"

Changed files
-------------
   optin.c             Accept new options for PVMPOV
   optin.h
   optout.c            Print new options and help texts for PVMPOV
   optout.h            
   povray.c            Major changes
   render.c            Minor changes
   render.h
