Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!know!samsung!munnari.oz.au!metro!ipso!fawlty!johnmac
From: johnmac@fawlty.towers.oz (John MacLean)
Newsgroups: comp.sys.apple2
Subject: Re: 3200 file format standard (NO REVERSED PALETTES!)
Message-ID: <434@fawlty.towers.oz>
Date: 6 Aug 90 00:23:22 GMT
Reply-To: johnmac@fawlty.ips.oz (John MacLean)
Organization: Tower Technology, Lane Cove, NSW, Australia
Lines: 44

In article <1990Aug1.231338.7751@laguna.ccsf.caltech.edu> toddpw@tybalt.caltech.edu (Todd P. Whitesel) writes:
>About the palette reversals (essentially, GET RID OF THEM!):
>I feel very strongly that a standard format should NOT reverse or convolute
>the palette data in ANY way whatsoever, in spite of the 'all the existing
>formats do it' reasoning.
>
>Todd Whitesel
>toddpw @ tybalt.caltech.edu

Todd,
	you'll be happy to know that palettes are not reversed in all the
existing formats as I was led to believe.
I only recievied my first external source of 3200 pics a few days ago, and
they were totally incompatible with the pics I had created.

It is also NOT true that the palettes themselves are reversed.

This all comes from the fact that most source going around uses palette $F
for scanline 0, $E for palette 1 etc, etc.
Most source also puts the last color in each palette into memory first.

The palette data in all formats is:

+$00 Palette for scanline 0:  color0 color1 color2 ..... color F
+$20 Palette for scanline 1:  ..........
............
+$1E0 Palette for scanline 199: color0 ..... color F

Just as I and everyone else would have initially hoped.

As for the standard form in APF. This seems to imply that we might as well
use the 'PALETTE' chunk.
Any APF file with a MAIN and a PALETTE with the number of scanlines ==
the number of palettes is a multi palette picture.

I'll stick with Brooks format for uncompressed - but change the filetype.
Again - pass this on for anyone interested.

John MacLean.
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