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using Manic Miner and Jet Set Willy game engines
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Message: 6292
Author: Hervé
Date: 14/10/2007
Subject: Re: Creating multicolour vertical guardians in JSW64 using JSWED
In manicminerandjetsetwilly@yahoogroups.com, andrewbroad wrote:
I've just spent ages debugging a colour-cycling guardian in JSW64
(any variant, but Z in particular) using JSWED (2.2.9 <= v <=
2.3.1).
When adding a new guardian to a JSW64 room, JSWED creates a default guardian with a first byte (GB0) of #12.
After changing the guardian-type to "Vertical multicolour", this byte changes to #17 - and therein lies the problem. It looks okay in
JSWED, but when playing the game, the guardian disappears after the first few time-frames - along with any guardians which come after it in the room's guardian-list. (I'm guessing that Bit 4 of GB0 causes it to go black (as it does in JSWED) and causes a premature return
from a subroutine.)This guardian can be fixed by simply changing the first byte (GB0)
from #17 to #07 - but it has just taken me ages to figure that out, culminating in an experiment where I converted JSW128 (the game) to JSW64 in order to convince myself that multicolour VGs work in JSW64 at all, and to compare my guardian with the colour-cycling VG in
"Top Landing" [34].
I have noticed this bug when I created "Willy on the Transatlantic
Cruise", in fact, now I take advantage of this bug to create an
effect of a monster fixed that disappears rapidly and without
returning.
It's a useful effect, but now I will use also the "Vertical
multicolour" with the bug deleted as you indicated! Thanks.
Hervé
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