[comp.sys.amiga] WARNING: A large GOTCHA when running DBW_Render on a VAX

wecker@cookie.dec.com.UUCP (04/05/87)

Guess what? I lied about the RAY software working on a VAX. Well sort of....

It compiles, and runs. However, everyone who tries to download the .TMP file
gets garbage. The reason? Simple, the VAX does numbers from low to high byte
and the 68000 does the opposite. So all of the fwrite() calls (in FIL.C) have
to be replaced with the appropriate "number flipping" routine.

FYI:	I have done this (as part of working on DBW_Render V2.0) and also
	made a version of RAY2 which runs on the VAX. These will be available
	as part of the major DBW_Render rewrite (hopefully in a few months).

BTW:	RAY2 has been changed to do a "median split" algorithm instead
	of a "poularity" based one which means that non-ham (32 color images)
	are almost indecernable from the HAM (4096 color) versions! See the
	1986 SIGRAPH proceedings for details on color compression.

keithd@cadovax.UUCP (04/08/87)

In article <9062@decwrl.DEC.COM> wecker@cookie.dec.com (DAVE  CUM GRANO SALIS  WECKER) writes:
>
>FYI:	I have done this (as part of working on DBW_Render V2.0) and also
>	made a version of RAY2 which runs on the VAX. These will be available
>	as part of the major DBW_Render rewrite (hopefully in a few months).
>
>BTW:	RAY2 has been changed to do a "median split" algorithm instead
>	of a "poularity" based one which means that non-ham (32 color images)
>	are almost indecernable from the HAM (4096 color) versions! See the
>	1986 SIGRAPH proceedings for details on color compression.


Sounds great!   I've been wanting to use our VAX for the ray tracer since
my Amiga is not idle long enough to provide enough time to do any images.

BTW, Dave, I heard a rumor that Byte by Byte has picked up the rights to
your animation stuff (used to do the juggler).  Is this true?  Does this
mean future versions of your software is going over the counter and we'll
have to negotiate with them?  What's the scoop?

Keith Doyle
#  {ucbvax,ihnp4,decvax}!trwrb!cadovax!keithd
#  cadovax!keithd@ucla-locus.arpa

papa@bacall.UUCP (Marco Papa) (04/10/87)

Keith Doyle write about Dave Wecker's DW_RENDER ray tracing program:
> Sounds great!   I've been wanting to use our VAX for the ray tracer since
> my Amiga is not idle long enough to provide enough time to do any images.
> 
> BTW, Dave, I heard a rumor that Byte by Byte has picked up the rights to
> your animation stuff (used to do the juggler).  Is this true?  Does this
> mean future versions of your software is going over the counter and we'll
> have to negotiate with them?  What's the scoop?
>

Keith, I think you have confused Dave's Ray Tracer with Eric Graham's (the
author of the juggler) ray tracer.  AmigaWorld reports that Graham's ray
tracer will be available from Byte by Byte this summer.

-- Marco