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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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