Date   : Fri, 20 Dec 2013 00:43:00 +0000
From   : jgh@... (J.G.Harston)
Subject: Physical colour numbers

Anders Carlsson wrote:
> The C64 palette has this order:
>
> 0 Black   > 8 Brown (not particularly bright)
> 1 White   > 9 Orange
> 2 Red     > 10 Pink
> 3 Cyan    > 11 Dark grey (ditto)
> 4 Purple  > 12 Medium grey
> 5 Green   > 13 Light green
> 6 Blue    > 14 Light blue
> 7 Yellow  > 15 Light grey
>
> I don't know what you can make out of those. Surely you could 
> rearrange the
> primitives (BBC Micro colours) in desired order on all systems,

Yes, the C64 host interface rearranges the native hardware colours into the
standard RGB values (mdfs.net/BBCBasic/C64):

0: black      8: orange
1: red        9: bright red (pink)
2: green     10: bright green
3: yellow    11: bright yellow (grey)
4: blue      12: bright blue
5: magenta   13: grey
6: cyan      14: dark grey
7: white     15: brown

The Spectrum's hardware colours also aren't RGB, they're BRG so are also
rearranged.

> The VDP in MSX, ColecoVision, TI-99/4A etc is even worse:
>
> 0 = Transparent      > 8 = Medium orange
> 1 = Black?           > 9 = Light orange
> 2 = Medium green     > 10 = Yellow
> 3 = Light green      > 11 = Light yellow
> 4 = Medium blue      > 12 = Dark green
> 5 = Light blue       > 13 = Purple
> 6 = orange/brown     > 14 = Light grey
> 7 = Light turquoise  > 15 = White

That's actually the standard RGB+bright colour list, but ordered as
Red:Green:Blue:Intensity with 0 as transparent instead of IBGR, and
a rather eclectic choice of names. "dark green" is actually dark
magenta, which is a sort-of dark green, medium and light orange are
actually dark red and bright red, the orange and torquoise is the
hardware tweeked to bend dark and bright cyan.

-- 
J.G.Harston - jgh@...      - mdfs.net