Hello, please don't think that I am off the hook here, but I have a bit of
a strange request.

I have been searching high and low for a 'text only' version of POV-Ray for
DOS, IE. withouth the proprietary UI that is built in to the Official
releaseof POV-Ray for DOS, I had the sources compiled for the generic UNIX
version under Mingw32 and DJGPP. These both ran properly, but at a
significantly higher render time.

Most often doubling the time it took to render, the same image at the same
resolution. I compiled the generic unix version in linux and it ran at the
same, slow speed. This lead me to believe at that point, that the code was
not optimized as well in the UNIX distribution... however. (See below for
Render times and command line options)

Finally I found that by changing one line in the DOS source file config.h
you could comment out the line
  #define FANCY_TEXT
and actually disable all of the UI stuff, exactly what I was hoping to do. I
compiled this (mind you this was almost the only change made) and still,
significantly slower render speeds.

I am now beginning to believe that the Watcom C++ compiler that the POV-Ray
Development team uses creates a much faster executable file than DJGPP does.
(DJGPP optimizations were set to +O3, maximum) If anyone reading this has a
Watcom compiler, you would do me a great favor to follow my simple
instructions below and compile this new executable for me! It should only
take a matter of minutes!

Watcom Users: To compile the source, simply download povmsd_s.zip from the
povray.org website and decompress it with the -d option. Change directory
into .\source\msdos\ and replace config.h with the one supplied in this
post. then change directory to .\source\msdos\watcom and type
WMAKE -f MSDOSWAT.MAK
That should compile the application with no problem! Thanks for your time!


Thanks in advance

RENDERING: .\povray\scenes\camera1a.pov @ 640x480:
COMMAND: povray +Icamera1a.pov +Ocamera1a.tga +W640 +H480
+L\windows\povray\include

TIMES:
DJGPP:           48 seconds
Mingw32:        43 seconds
PGCC: *          47 seconds
OFFICIAL:      36 seconds

* PGCC is a replacement for the GCC compiler packaged with DJGPP, it is
supposed to increase application performance anywhere from 5%-30%. As you
can see here, it made little difference, also indicating that the
application is optimized to the best of DJGPP's abilities.

Thanks again for your time.


 - Tim -

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Would have been a very motivating message, had I remembered to attach the
file, anyway, her it is :)

- Tim -

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Attachments:
Download 'Config.h.txt' (8 KB)

I've compiled the DOS version of POV-Ray 3.1e with djgcc 2.8.1 and have
optimised it to the point where it runs at the same speed as the official
Watcom compile.

The CFLAGS I used were:
# For gcc 2.81
CFLAGS=-O3 -s -mcpu=pentiumpro -march=pentiumpro \
 -malign-double -malign-loops=2 -malign-jumps=2 -malign-functions=2 \
 -fomit-frame-pointer -fno-exceptions -fforce-addr -fforce-mem \
 -funroll-loops -ffast-math

This renders skyvase.pov at 640 x 480 in 1 min 11 secs on my Celeron 333a.
The Watcom version does it in 1 min 12 secs!

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