Resource centre for ZX Spectrum games
using Manic Miner and Jet Set Willy game engines
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Manic Miner & Jet Set Willy Yahoo! Group
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Message: 4085
Author: andrewbroad
Date: 16/04/2004
Subject: Re: Changing Willy's colour
john_elliott_uk wrote:
> andrewbroad wrote:Of course - I was incorrect when I wrote "AND 0" earlier. AND 0
> >
> > This doesn't actually change Willy's colour, but rather the OR-
> > mask which is applied to the background INK-colour to generate
> > Willy's colour.
>
> See also the 'black Willy' patch from JSWED:
>
> PatchLine plBlackWilly[] = {
> { 0x962C, 0xF6, 0xE6},
> { 0x962D, 0x07, 0xF8},
> { 0x9280, 0x07, 0x00},
> { 0x93F0, 0x07, 0x00},
> };
>
> (that is: replace OR 7 with AND F8, and check for ink 0
> accordingly).
would knock out the FLASH, BRIGHT and PAPER bits. AND &F8 (to apply
an AND-mask of 11111000) is what is needed for a black-ink Willy
(and a coloured Willy could be produced properly by replacing OR 7
with AND &F8 followed by OR x, with appropriate code-motion).
--
Dr. Andrew Broad
http://www.geocities.com/andrewbroad/
http://www.geocities.com/andrewbroad/spectrum/
http://www.geocities.com/andrewbroad/spectrum/willy/
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